Current Situation: Emissions from Connecting Flights
Currently, many UK passengers flying long-haul must first take a short-haul flight to a European hub (e.g., Amsterdam Schiphol, Paris Charles de Gaulle, Frankfurt) before continuing their journey. These connecting flights introduce additional fuel consumption, emissions, and inefficiencies due to:
- Extra takeoff and landing cycles, which are fuel-intensive
A short-haul flight from Heathrow to Amsterdam (Schiphol) emits approximately 80-100 kg CO₂ per passenger (for a Boeing 737-800/A320).
A long-haul flight from Schiphol to New York (JFK) emits around 1.5-2.0 tonnes CO₂ per passenger on a Boeing 787 or A350.
Adding those together:
- With a connection (LHR → AMS → JFK): 100 kg CO₂ (LHR-AMS) + 1,800 kg CO₂ (AMS-JFK) = 1.9 tonnes CO₂ per passenger
- With a direct Heathrow-JFK flight: 1.7 tonnes CO₂ per passenger
This suggests a potential saving of 200 kg CO₂ per passenger by avoiding the connection.
Estimating GHG Savings from Heathrow’s Third Runway
Heathrow’s third runway is expected to allow an increase in direct long-haul routes, which should reduce the number of passengers transiting via European hubs.
Estimated Passenger Shift
- The UK Department for Transport estimated that a third runway would add 260,000 additional flights per year (mostly long-haul).
- If even 10 million passengers per year switch from indirect to direct flights, and each avoids 200 kg CO₂ per trip, that results in:
10,000,000 x 200kg CO₂ = 2 million tonnes CO₂ saved annually
That’s a significant emissions saving, equivalent to taking nearly 1 million cars off the road (assuming ~2 tonnes CO₂ per car per year).
Will Heathrow’s Third Runway Still Increase Overall Emissions?
Even with these savings, it’s worth noting that a third runway increases total capacity, meaning:
- More flights overall (including new short-haul feeder routes)
- More aviation emissions, as total air traffic grows
- Indirect emissions from airport expansion and increased ground transport
However, compared to a scenario where Heathrow remains constrained and passengers continue flying via Europe, the third runway could be the lesser evil in terms of per-passenger emissions efficiency.
- Increasing long-haul capacity at Heathrow could reduce per-passenger emissions by cutting unnecessary short-haul connections to European hubs.
- Potential savings: ~2 million tonnes CO₂ per year**, if enough passengers switch to direct long-haul routes.
- However, **total aviation emissions will still rise**, since more flights will operate overall.
If emissions reduction is the primary goal, Heathrow’s third runway alone isn’t the silver bullet, but it can contribute to a more efficient aviation network by reducing indirect flight emissions. As well as completing the third runway as soon as possible, the government should stipulate that its use is confined to the latest generations of fuel efficient aircraft (e.g. Boeing 787, Airbus A350) which are about 25% more fuel-efficient than older models.
It misses the point, instead of expanding air travel, it should be reduced.
There will not be a reduction in the amount of air travel. Nothing we do now, or in the future, will decrease the amount of air travel undertaken globally, regionally or (most importantly for an island nation) to and from our country.
Once we understand that, then the task must be how we ameliorate the climate effects of air travel. That's by ensuring all flights - or, as many as possible, are undertaken via routes and modes that are as efficient as possible. That's by ensuring flights are operated at the lowest cost per passenger in terms of emissions; by ensuring flights between cities that can be reached in reasonable time by a cleaner mode should be banned; and by ensuring investment and incentives in the cleanest aircraft and the most sustainable fuels.
If we want to combat greenhouse gas emissions by crossing our fingers and hoping people decide to stop flying, we will fail, quickly and completely.
Current Situation: Emissions from Connecting Flights
Currently, many UK passengers flying long-haul must first take a short-haul flight to a European hub (e.g., Amsterdam Schiphol, Paris Charles de Gaulle, Frankfurt) before continuing their journey. These connecting flights introduce additional fuel consumption, emissions, and inefficiencies due to:
- Extra takeoff and landing cycles, which are fuel-intensive
A short-haul flight from Heathrow to Amsterdam (Schiphol) emits approximately 80-100 kg CO₂ per passenger (for a Boeing 737-800/A320).
A long-haul flight from Schiphol to New York (JFK) emits around 1.5-2.0 tonnes CO₂ per passenger on a Boeing 787 or A350.
Adding those together:
- With a connection (LHR → AMS → JFK): 100 kg CO₂ (LHR-AMS) + 1,800 kg CO₂ (AMS-JFK) = 1.9 tonnes CO₂ per passenger
- With a direct Heathrow-JFK flight: 1.7 tonnes CO₂ per passenger
This suggests a potential saving of 200 kg CO₂ per passenger by avoiding the connection.
Estimating GHG Savings from Heathrow’s Third Runway
Heathrow’s third runway is expected to allow an increase in direct long-haul routes, which should reduce the number of passengers transiting via European hubs.
Estimated Passenger Shift
- The UK Department for Transport estimated that a third runway would add 260,000 additional flights per year (mostly long-haul).
- If even 10 million passengers per year switch from indirect to direct flights, and each avoids 200 kg CO₂ per trip, that results in:
10,000,000 x 200kg CO₂ = 2 million tonnes CO₂ saved annually
That’s a significant emissions saving, equivalent to taking nearly 1 million cars off the road (assuming ~2 tonnes CO₂ per car per year).
Will Heathrow’s Third Runway Still Increase Overall Emissions?
Even with these savings, it’s worth noting that a third runway increases total capacity, meaning:
- More flights overall (including new short-haul feeder routes)
- More aviation emissions, as total air traffic grows
- Indirect emissions from airport expansion and increased ground transport
However, compared to a scenario where Heathrow remains constrained and passengers continue flying via Europe, the third runway could be the lesser evil in terms of per-passenger emissions efficiency.
- Increasing long-haul capacity at Heathrow could reduce per-passenger emissions by cutting unnecessary short-haul connections to European hubs.
- Potential savings: ~2 million tonnes CO₂ per year**, if enough passengers switch to direct long-haul routes.
- However, **total aviation emissions will still rise**, since more flights will operate overall.
If emissions reduction is the primary goal, Heathrow’s third runway alone isn’t the silver bullet, but it can contribute to a more efficient aviation network by reducing indirect flight emissions. As well as completing the third runway as soon as possible, the government should stipulate that its use is confined to the latest generations of fuel efficient aircraft (e.g. Boeing 787, Airbus A350) which are about 25% more fuel-efficient than older models.
It misses the point, instead of expanding air travel, it should be reduced.
With an expanding population everything will expand with it. More house building More hospitals More Doctors surgeries More Schools More Roads More Demand for gas and electricity More Demand for food And unfortunately More Flights.
With the UK population predicted to increase by several million over the next decade I'm afraid it comes without it's problems.
By the time a plane from Heathrow 3rd runway project gets off the ground, (est. 2035), C02 concentrations will be beyond 450 parts per million, so say the scientists, and given their track record of predictions so far, it may be sooner. The effects of climate change will only escalate with world leaders putting their foot on the gas to accelerate economic growth, so reaching that vital tipping point sooner.
We were advised in 2020 that we needed to halve emissions globally by the end of the decade, and with the exception of the COVID year, when flights were grounded with it treated as an emergency, they've been increasing year on year since.
Climate change isn't being treated as an emergency. Economic growth takes precedence over environmental concerns, and trying to discredit or silence those sounding the alarm is more important than trying to put out the fire.
Is the announcement today a sign of giving up on climate objectives, an acceptance that it's probably too late now anyway and we should all make hay whilst the sun shines? And is it really possible to grow economies worldwide, with growing populations, in a way that doesn't destabilize the balance of nature and climate?
Looks like I picked the wrong week to stop posting 🤣
I remember some time ago hearing a programme on Radio 4 about two different but related problems to do with road traffic. Why is it that certain roads never seem to be free of congestion despite major widening programmes and why is it that you can never get a parking space near a hospital even after they've had multi-story car parks built their grounds?*. The conclusion to both of these seemed to be that there's a two-way relationship between supply and demand. Planners increase capacity to meet current (and anticipated) demand, but in doing so they stimulate further demand, leading to a reintroduction of the original problem, only on a bigger scale. I can't help but wonder if the exact same processes work for supply and demand regarding airport capacity. I guess we will find out if we live long enough.
*This was several years ago, when people could actually go to hospitals.
I remember some time ago hearing a programme on Radio 4 about two different but related problems to do with road traffic. Why is it that certain roads never seem to be free of congestion despite major widening programmes and why is it that you can never get a parking space near a hospital even after they've had multi-story car parks built their grounds?*. The conclusion to both of these seemed to be that there's a two-way relationship between supply and demand. Planners increase capacity to meet current (and anticipated) demand, but in doing so they stimulate further demand, leading to a reintroduction of the original problem, only on a bigger scale. I can't help but wonder if the exact same processes work for supply and demand regarding airport capacity. I guess we will find out if we live long enough.
*This was several years ago, when people could actually go to hospitals.
A quote from The Field of Dreams- if you build it they will come
1 will safely say the Heathrow runway will not be built in my lifetime. All the projects being put forward are not government funded. Denmark is building a road rail tunnel between Germany and Denmark length approx 18km at the cost of £10b not only reducing traveling times but also emissions, it will be quicker to travel by train between Hamburg and Copenhagen than flying . The Lower Thames crossing is projected to cost £9b with almost £1b already spent before any works start. Perhaps we should ask the Danes to build a new road/rail Channel Tunnel so people could get to continental airports quicker than getting short flights from Heathrow, This country is useless at planning and building major projects.
Investing in infrastructure is good. Trust the analysis/ arguments that say it will be a net positive for the country’s economy.
Interesting will be how far Mayor Khan goes with his objections. Not enough to forego his knighthood I suspect.
The serious point being it’s opposed to the government when he campaigned partly on being Labour aligned and the benefit that should bring on supporting London.
On balance I thinking may be the best decision if it’s quickly followed through
I remember some time ago hearing a programme on Radio 4 about two different but related problems to do with road traffic. Why is it that certain roads never seem to be free of congestion despite major widening programmes and why is it that you can never get a parking space near a hospital even after they've had multi-story car parks built their grounds?*. The conclusion to both of these seemed to be that there's a two-way relationship between supply and demand. Planners increase capacity to meet current (and anticipated) demand, but in doing so they stimulate further demand, leading to a reintroduction of the original problem, only on a bigger scale. I can't help but wonder if the exact same processes work for supply and demand regarding airport capacity. I guess we will find out if we live long enough.
*This was several years ago, when people could actually go to hospitals.
Indeed. It's called 'induced demand' and is a well known phenomenon in traffic management
Current Situation: Emissions from Connecting Flights
Currently, many UK passengers flying long-haul must first take a short-haul flight to a European hub (e.g., Amsterdam Schiphol, Paris Charles de Gaulle, Frankfurt) before continuing their journey. These connecting flights introduce additional fuel consumption, emissions, and inefficiencies due to:
- Extra takeoff and landing cycles, which are fuel-intensive
A short-haul flight from Heathrow to Amsterdam (Schiphol) emits approximately 80-100 kg CO₂ per passenger (for a Boeing 737-800/A320).
A long-haul flight from Schiphol to New York (JFK) emits around 1.5-2.0 tonnes CO₂ per passenger on a Boeing 787 or A350.
Adding those together:
- With a connection (LHR → AMS → JFK): 100 kg CO₂ (LHR-AMS) + 1,800 kg CO₂ (AMS-JFK) = 1.9 tonnes CO₂ per passenger
- With a direct Heathrow-JFK flight: 1.7 tonnes CO₂ per passenger
This suggests a potential saving of 200 kg CO₂ per passenger by avoiding the connection.
Estimating GHG Savings from Heathrow’s Third Runway
Heathrow’s third runway is expected to allow an increase in direct long-haul routes, which should reduce the number of passengers transiting via European hubs.
Estimated Passenger Shift
- The UK Department for Transport estimated that a third runway would add 260,000 additional flights per year (mostly long-haul).
- If even 10 million passengers per year switch from indirect to direct flights, and each avoids 200 kg CO₂ per trip, that results in:
10,000,000 x 200kg CO₂ = 2 million tonnes CO₂ saved annually
That’s a significant emissions saving, equivalent to taking nearly 1 million cars off the road (assuming ~2 tonnes CO₂ per car per year).
Will Heathrow’s Third Runway Still Increase Overall Emissions?
Even with these savings, it’s worth noting that a third runway increases total capacity, meaning:
- More flights overall (including new short-haul feeder routes)
- More aviation emissions, as total air traffic grows
- Indirect emissions from airport expansion and increased ground transport
However, compared to a scenario where Heathrow remains constrained and passengers continue flying via Europe, the third runway could be the lesser evil in terms of per-passenger emissions efficiency.
- Increasing long-haul capacity at Heathrow could reduce per-passenger emissions by cutting unnecessary short-haul connections to European hubs.
- Potential savings: ~2 million tonnes CO₂ per year**, if enough passengers switch to direct long-haul routes.
- However, **total aviation emissions will still rise**, since more flights will operate overall.
If emissions reduction is the primary goal, Heathrow’s third runway alone isn’t the silver bullet, but it can contribute to a more efficient aviation network by reducing indirect flight emissions. As well as completing the third runway as soon as possible, the government should stipulate that its use is confined to the latest generations of fuel efficient aircraft (e.g. Boeing 787, Airbus A350) which are about 25% more fuel-efficient than older models.
Hmm, I'm not convinced by the calculations How many connecting flights are being made that way because it's cheaper (vs. no direct flight being available)?
Let's say the additional flights carry 200 people each (which is a very conservative figure). So 52,000,000 additional passengers, and against that you have just 10,000,000 who are now taking direct flights. The net increase in emissions is surely huge (if my maths is correct)
Plus the impact of additional airport traffic, inc airport services, not to mention all the construction emissions.
I don't see how you can increase the number of flights from LHR without a significant increase in carbon footprint. Yes that's true for pretty much any economic activity (= 'growth'), but disproportionately so in the case of air travel expansion.
I remember some time ago hearing a programme on Radio 4 about two different but related problems to do with road traffic. Why is it that certain roads never seem to be free of congestion despite major widening programmes and why is it that you can never get a parking space near a hospital even after they've had multi-story car parks built their grounds?*. The conclusion to both of these seemed to be that there's a two-way relationship between supply and demand. Planners increase capacity to meet current (and anticipated) demand, but in doing so they stimulate further demand, leading to a reintroduction of the original problem, only on a bigger scale. I can't help but wonder if the exact same processes work for supply and demand regarding airport capacity. I guess we will find out if we live long enough.
*This was several years ago, when people could actually go to hospitals.
Indeed. It's called 'induced demand' and is a well known phenomenon in traffic management
Also related is Jevons Paradox: making a resource more efficient leads to more consumption of that resource, for example because it will be cheaper.
Current Situation: Emissions from Connecting Flights
Currently, many UK passengers flying long-haul must first take a short-haul flight to a European hub (e.g., Amsterdam Schiphol, Paris Charles de Gaulle, Frankfurt) before continuing their journey. These connecting flights introduce additional fuel consumption, emissions, and inefficiencies due to:
- Extra takeoff and landing cycles, which are fuel-intensive
A short-haul flight from Heathrow to Amsterdam (Schiphol) emits approximately 80-100 kg CO₂ per passenger (for a Boeing 737-800/A320).
A long-haul flight from Schiphol to New York (JFK) emits around 1.5-2.0 tonnes CO₂ per passenger on a Boeing 787 or A350.
Adding those together:
- With a connection (LHR → AMS → JFK): 100 kg CO₂ (LHR-AMS) + 1,800 kg CO₂ (AMS-JFK) = 1.9 tonnes CO₂ per passenger
- With a direct Heathrow-JFK flight: 1.7 tonnes CO₂ per passenger
This suggests a potential saving of 200 kg CO₂ per passenger by avoiding the connection.
Estimating GHG Savings from Heathrow’s Third Runway
Heathrow’s third runway is expected to allow an increase in direct long-haul routes, which should reduce the number of passengers transiting via European hubs.
Estimated Passenger Shift
- The UK Department for Transport estimated that a third runway would add 260,000 additional flights per year (mostly long-haul).
- If even 10 million passengers per year switch from indirect to direct flights, and each avoids 200 kg CO₂ per trip, that results in:
10,000,000 x 200kg CO₂ = 2 million tonnes CO₂ saved annually
That’s a significant emissions saving, equivalent to taking nearly 1 million cars off the road (assuming ~2 tonnes CO₂ per car per year).
Will Heathrow’s Third Runway Still Increase Overall Emissions?
Even with these savings, it’s worth noting that a third runway increases total capacity, meaning:
- More flights overall (including new short-haul feeder routes)
- More aviation emissions, as total air traffic grows
- Indirect emissions from airport expansion and increased ground transport
However, compared to a scenario where Heathrow remains constrained and passengers continue flying via Europe, the third runway could be the lesser evil in terms of per-passenger emissions efficiency.
- Increasing long-haul capacity at Heathrow could reduce per-passenger emissions by cutting unnecessary short-haul connections to European hubs.
- Potential savings: ~2 million tonnes CO₂ per year**, if enough passengers switch to direct long-haul routes.
- However, **total aviation emissions will still rise**, since more flights will operate overall.
If emissions reduction is the primary goal, Heathrow’s third runway alone isn’t the silver bullet, but it can contribute to a more efficient aviation network by reducing indirect flight emissions. As well as completing the third runway as soon as possible, the government should stipulate that its use is confined to the latest generations of fuel efficient aircraft (e.g. Boeing 787, Airbus A350) which are about 25% more fuel-efficient than older models.
Hmm, I'm not convinced by the calculations How many connecting flights are being made that way because it's cheaper (vs. no direct flight being available)?
Let's say the additional flights carry 200 people each (which is a very conservative figure). So 52,000,000 additional passengers, and against that you have just 10,000,000 who are now taking direct flights. The net increase in emissions is surely huge (if my maths is correct)
Plus the impact of additional airport traffic, inc airport services, not to mention all the construction emissions.
I don't see how you can increase the number of flights from LHR without a significant increase in carbon footprint. Yes that's true for pretty much any economic activity (= 'growth'), but disproportionately so in the case of air travel expansion.
If you're only measuring flights from Heathrow then, of course, an increase in the number of flights will cause an increase in carbon emissions. But that's, of course, measuring the wrong thing.
If the total number of flights is brought down by the fact that more passengers can take direct flights (ie one, as opposed to two or more to reach their destination) then the carbon emissions will be reduced for those trips.
The point is "more flights from Heathrow" does not, necessarily mean "more flights".
Modern jet engines polute much less than older ones. Of course they still polute but in ten years time they are probably going to polute less than today.
Modern jet engines polute much less than older ones. Of course they still polute but in ten years time they are probably going to polute less than today.
In ten years time the effects of climate change are only going to be worse than they are today.
Modern jet engines polute much less than older ones. Of course they still polute but in ten years time they are probably going to polute less than today.
Heathrow had offered the massive incentive of landing-fee free flights for a year to the first airline to operate electric planes out of the airport.
My money is on that happening inside your ten year timescale.
Current Situation: Emissions from Connecting Flights
Currently, many UK passengers flying long-haul must first take a short-haul flight to a European hub (e.g., Amsterdam Schiphol, Paris Charles de Gaulle, Frankfurt) before continuing their journey. These connecting flights introduce additional fuel consumption, emissions, and inefficiencies due to:
- Extra takeoff and landing cycles, which are fuel-intensive
A short-haul flight from Heathrow to Amsterdam (Schiphol) emits approximately 80-100 kg CO₂ per passenger (for a Boeing 737-800/A320).
A long-haul flight from Schiphol to New York (JFK) emits around 1.5-2.0 tonnes CO₂ per passenger on a Boeing 787 or A350.
Adding those together:
- With a connection (LHR → AMS → JFK): 100 kg CO₂ (LHR-AMS) + 1,800 kg CO₂ (AMS-JFK) = 1.9 tonnes CO₂ per passenger
- With a direct Heathrow-JFK flight: 1.7 tonnes CO₂ per passenger
This suggests a potential saving of 200 kg CO₂ per passenger by avoiding the connection.
Estimating GHG Savings from Heathrow’s Third Runway
Heathrow’s third runway is expected to allow an increase in direct long-haul routes, which should reduce the number of passengers transiting via European hubs.
Estimated Passenger Shift
- The UK Department for Transport estimated that a third runway would add 260,000 additional flights per year (mostly long-haul).
- If even 10 million passengers per year switch from indirect to direct flights, and each avoids 200 kg CO₂ per trip, that results in:
10,000,000 x 200kg CO₂ = 2 million tonnes CO₂ saved annually
That’s a significant emissions saving, equivalent to taking nearly 1 million cars off the road (assuming ~2 tonnes CO₂ per car per year).
Will Heathrow’s Third Runway Still Increase Overall Emissions?
Even with these savings, it’s worth noting that a third runway increases total capacity, meaning:
- More flights overall (including new short-haul feeder routes)
- More aviation emissions, as total air traffic grows
- Indirect emissions from airport expansion and increased ground transport
However, compared to a scenario where Heathrow remains constrained and passengers continue flying via Europe, the third runway could be the lesser evil in terms of per-passenger emissions efficiency.
- Increasing long-haul capacity at Heathrow could reduce per-passenger emissions by cutting unnecessary short-haul connections to European hubs.
- Potential savings: ~2 million tonnes CO₂ per year**, if enough passengers switch to direct long-haul routes.
- However, **total aviation emissions will still rise**, since more flights will operate overall.
If emissions reduction is the primary goal, Heathrow’s third runway alone isn’t the silver bullet, but it can contribute to a more efficient aviation network by reducing indirect flight emissions. As well as completing the third runway as soon as possible, the government should stipulate that its use is confined to the latest generations of fuel efficient aircraft (e.g. Boeing 787, Airbus A350) which are about 25% more fuel-efficient than older models.
It misses the point, instead of expanding air travel, it should be reduced.
There will not be a reduction in the amount of air travel. Nothing we do now, or in the future, will decrease the amount of air travel undertaken globally, regionally or (most importantly for an island nation) to and from our country.
Once we understand that, then the task must be how we ameliorate the climate effects of air travel. That's by ensuring all flights - or, as many as possible, are undertaken via routes and modes that are as efficient as possible. That's by ensuring flights are operated at the lowest cost per passenger in terms of emissions; by ensuring flights between cities that can be reached in reasonable time by a cleaner mode should be banned; and by ensuring investment and incentives in the cleanest aircraft and the most sustainable fuels.
If we want to combat greenhouse gas emissions by crossing our fingers and hoping people decide to stop flying, we will fail, quickly and completely.
Flights were grounded during COVID though, and as the the climate becomes more unstable, the more extreme weather conditions predicted might make flying less popular as it becomes a less reliable form of travel, with more cancellations etc.
A third runway at Heathrow will increase greenhouse gas emissions significantly and have a devastating effect on biodiversity, air and noise pollution. To suggest otherwise is laughable and arguments about fewer flights elsewhere won't wash with environmentalists.
By sending the appalling message that we aren't taking our net zero targets seriously though, it might actually be a good thing for increasing awareness of the climate crisis we're in. It will bring environmentalists together in mass opposition around a single issue, the project likely to be being hampered by protests getting broad media coverage, so those on board with it can expect a very bumpy ride!
Modern jet engines polute much less than older ones. Of course they still polute but in ten years time they are probably going to polute less than today.
Heathrow had offered the massive incentive of landing-fee free flights for a year to the first airline to operate electric planes out of the airport.
My money is on that happening inside your ten year timescale.
Personally not sure electric planes are the solution but hydrogen cell may well be.
It's a difficult one as currently I want to be disincentivising flying and would be taxing it additionally. But if we are confident a carbon neutral way of flying can be delivered then we don't want to hold back infrastructure and future growth (despite my views on this being a terrible metric by which to measure an economy and society) by not building now.
If it was up to me I would say build it but at the same time would be taxing frequent flyers and taxing aviation fuel greater and massively taxing private jets. All under the polluter pays principle and in order to incentivise the development of whatever fuel is the future of air travel.
I don't know if we have the technology for electric planes that can do long haul.
Besides, by ditching kerosine and going for electric planes, you're just ditching one unsustainable aircraft for another. Hydrogen fuel can be artificially made and is obviously the future.
I don't know if we have the technology for electric planes that can do long haul.
Besides, by ditching kerosine and going for electric planes, you're just ditching one unsustainable aircraft for another. Hydrogen fuel can be artificially made and is obviously the future.
Tend to agree. The one thing that makes me think electric planes could work is solid state batteries (I know i keep going on about them). They are small, light, quick to charge and incredibly powerful. They will revolutionise cars/houses and the national grid. They may not be enough to work on planes but everything I have read has said they don't know the upside limit of where the tech can go. It may well be possible that they can develop to a point they can power electric planes for long haul flights.
Current Situation: Emissions from Connecting Flights
Currently, many UK passengers flying long-haul must first take a short-haul flight to a European hub (e.g., Amsterdam Schiphol, Paris Charles de Gaulle, Frankfurt) before continuing their journey. These connecting flights introduce additional fuel consumption, emissions, and inefficiencies due to:
- Extra takeoff and landing cycles, which are fuel-intensive
A short-haul flight from Heathrow to Amsterdam (Schiphol) emits approximately 80-100 kg CO₂ per passenger (for a Boeing 737-800/A320).
A long-haul flight from Schiphol to New York (JFK) emits around 1.5-2.0 tonnes CO₂ per passenger on a Boeing 787 or A350.
Adding those together:
- With a connection (LHR → AMS → JFK): 100 kg CO₂ (LHR-AMS) + 1,800 kg CO₂ (AMS-JFK) = 1.9 tonnes CO₂ per passenger
- With a direct Heathrow-JFK flight: 1.7 tonnes CO₂ per passenger
This suggests a potential saving of 200 kg CO₂ per passenger by avoiding the connection.
Estimating GHG Savings from Heathrow’s Third Runway
Heathrow’s third runway is expected to allow an increase in direct long-haul routes, which should reduce the number of passengers transiting via European hubs.
Estimated Passenger Shift
- The UK Department for Transport estimated that a third runway would add 260,000 additional flights per year (mostly long-haul).
- If even 10 million passengers per year switch from indirect to direct flights, and each avoids 200 kg CO₂ per trip, that results in:
10,000,000 x 200kg CO₂ = 2 million tonnes CO₂ saved annually
That’s a significant emissions saving, equivalent to taking nearly 1 million cars off the road (assuming ~2 tonnes CO₂ per car per year).
Will Heathrow’s Third Runway Still Increase Overall Emissions?
Even with these savings, it’s worth noting that a third runway increases total capacity, meaning:
- More flights overall (including new short-haul feeder routes)
- More aviation emissions, as total air traffic grows
- Indirect emissions from airport expansion and increased ground transport
However, compared to a scenario where Heathrow remains constrained and passengers continue flying via Europe, the third runway could be the lesser evil in terms of per-passenger emissions efficiency.
- Increasing long-haul capacity at Heathrow could reduce per-passenger emissions by cutting unnecessary short-haul connections to European hubs.
- Potential savings: ~2 million tonnes CO₂ per year**, if enough passengers switch to direct long-haul routes.
- However, **total aviation emissions will still rise**, since more flights will operate overall.
If emissions reduction is the primary goal, Heathrow’s third runway alone isn’t the silver bullet, but it can contribute to a more efficient aviation network by reducing indirect flight emissions. As well as completing the third runway as soon as possible, the government should stipulate that its use is confined to the latest generations of fuel efficient aircraft (e.g. Boeing 787, Airbus A350) which are about 25% more fuel-efficient than older models.
Hmm, I'm not convinced by the calculations How many connecting flights are being made that way because it's cheaper (vs. no direct flight being available)?
Let's say the additional flights carry 200 people each (which is a very conservative figure). So 52,000,000 additional passengers, and against that you have just 10,000,000 who are now taking direct flights. The net increase in emissions is surely huge (if my maths is correct)
Plus the impact of additional airport traffic, inc airport services, not to mention all the construction emissions.
I don't see how you can increase the number of flights from LHR without a significant increase in carbon footprint. Yes that's true for pretty much any economic activity (= 'growth'), but disproportionately so in the case of air travel expansion.
If you're only measuring flights from Heathrow then, of course, an increase in the number of flights will cause an increase in carbon emissions. But that's, of course, measuring the wrong thing.
If the total number of flights is brought down by the fact that more passengers can take direct flights (ie one, as opposed to two or more to reach their destination) then the carbon emissions will be reduced for those trips.
The point is "more flights from Heathrow" does not, necessarily mean "more flights".
I think you'll find that the underlying assumption is an expansion in air travel overall. As some have pointed out, population increase alone will push that, as will more mobile societies generally. If (big IF!) the goal of economic growthbis achieved that will hopefully mean some currently cash-strapped people would be able to afford holidays abroad.
Do we simply accept this trend, or try and.push back (in ways which will undoubtedly be unpopular with some, eg rationing numbers of flights per person/yesr, or hiking air taxes to levels which reduce demand)?
Current Situation: Emissions from Connecting Flights
Currently, many UK passengers flying long-haul must first take a short-haul flight to a European hub (e.g., Amsterdam Schiphol, Paris Charles de Gaulle, Frankfurt) before continuing their journey. These connecting flights introduce additional fuel consumption, emissions, and inefficiencies due to:
- Extra takeoff and landing cycles, which are fuel-intensive
A short-haul flight from Heathrow to Amsterdam (Schiphol) emits approximately 80-100 kg CO₂ per passenger (for a Boeing 737-800/A320).
A long-haul flight from Schiphol to New York (JFK) emits around 1.5-2.0 tonnes CO₂ per passenger on a Boeing 787 or A350.
Adding those together:
- With a connection (LHR → AMS → JFK): 100 kg CO₂ (LHR-AMS) + 1,800 kg CO₂ (AMS-JFK) = 1.9 tonnes CO₂ per passenger
- With a direct Heathrow-JFK flight: 1.7 tonnes CO₂ per passenger
This suggests a potential saving of 200 kg CO₂ per passenger by avoiding the connection.
Estimating GHG Savings from Heathrow’s Third Runway
Heathrow’s third runway is expected to allow an increase in direct long-haul routes, which should reduce the number of passengers transiting via European hubs.
Estimated Passenger Shift
- The UK Department for Transport estimated that a third runway would add 260,000 additional flights per year (mostly long-haul).
- If even 10 million passengers per year switch from indirect to direct flights, and each avoids 200 kg CO₂ per trip, that results in:
10,000,000 x 200kg CO₂ = 2 million tonnes CO₂ saved annually
That’s a significant emissions saving, equivalent to taking nearly 1 million cars off the road (assuming ~2 tonnes CO₂ per car per year).
Will Heathrow’s Third Runway Still Increase Overall Emissions?
Even with these savings, it’s worth noting that a third runway increases total capacity, meaning:
- More flights overall (including new short-haul feeder routes)
- More aviation emissions, as total air traffic grows
- Indirect emissions from airport expansion and increased ground transport
However, compared to a scenario where Heathrow remains constrained and passengers continue flying via Europe, the third runway could be the lesser evil in terms of per-passenger emissions efficiency.
- Increasing long-haul capacity at Heathrow could reduce per-passenger emissions by cutting unnecessary short-haul connections to European hubs.
- Potential savings: ~2 million tonnes CO₂ per year**, if enough passengers switch to direct long-haul routes.
- However, **total aviation emissions will still rise**, since more flights will operate overall.
If emissions reduction is the primary goal, Heathrow’s third runway alone isn’t the silver bullet, but it can contribute to a more efficient aviation network by reducing indirect flight emissions. As well as completing the third runway as soon as possible, the government should stipulate that its use is confined to the latest generations of fuel efficient aircraft (e.g. Boeing 787, Airbus A350) which are about 25% more fuel-efficient than older models.
Hmm, I'm not convinced by the calculations How many connecting flights are being made that way because it's cheaper (vs. no direct flight being available)?
Let's say the additional flights carry 200 people each (which is a very conservative figure). So 52,000,000 additional passengers, and against that you have just 10,000,000 who are now taking direct flights. The net increase in emissions is surely huge (if my maths is correct)
Plus the impact of additional airport traffic, inc airport services, not to mention all the construction emissions.
I don't see how you can increase the number of flights from LHR without a significant increase in carbon footprint. Yes that's true for pretty much any economic activity (= 'growth'), but disproportionately so in the case of air travel expansion.
If you're only measuring flights from Heathrow then, of course, an increase in the number of flights will cause an increase in carbon emissions. But that's, of course, measuring the wrong thing.
If the total number of flights is brought down by the fact that more passengers can take direct flights (ie one, as opposed to two or more to reach their destination) then the carbon emissions will be reduced for those trips.
The point is "more flights from Heathrow" does not, necessarily mean "more flights".
I think you'll find that the underlying assumption is an expansion in air travel overall. As some have pointed out, population increase alone will push that, as will more mobile societies generally. If (big IF!) the goal of economic growthbis achieved that will hopefully mean some currently cash-strapped people would be able to afford holidays abroad.
Do we simply accept this trend, or try and.push back (in ways which will undoubtedly be unpopular with some, eg rationing numbers of flights per person/yesr, or hiking air taxes to levels which reduce demand)?
Not building a third runway at Heathrow will not decrease demand for air travel.
Current Situation: Emissions from Connecting Flights
Currently, many UK passengers flying long-haul must first take a short-haul flight to a European hub (e.g., Amsterdam Schiphol, Paris Charles de Gaulle, Frankfurt) before continuing their journey. These connecting flights introduce additional fuel consumption, emissions, and inefficiencies due to:
- Extra takeoff and landing cycles, which are fuel-intensive
A short-haul flight from Heathrow to Amsterdam (Schiphol) emits approximately 80-100 kg CO₂ per passenger (for a Boeing 737-800/A320).
A long-haul flight from Schiphol to New York (JFK) emits around 1.5-2.0 tonnes CO₂ per passenger on a Boeing 787 or A350.
Adding those together:
- With a connection (LHR → AMS → JFK): 100 kg CO₂ (LHR-AMS) + 1,800 kg CO₂ (AMS-JFK) = 1.9 tonnes CO₂ per passenger
- With a direct Heathrow-JFK flight: 1.7 tonnes CO₂ per passenger
This suggests a potential saving of 200 kg CO₂ per passenger by avoiding the connection.
Estimating GHG Savings from Heathrow’s Third Runway
Heathrow’s third runway is expected to allow an increase in direct long-haul routes, which should reduce the number of passengers transiting via European hubs.
Estimated Passenger Shift
- The UK Department for Transport estimated that a third runway would add 260,000 additional flights per year (mostly long-haul).
- If even 10 million passengers per year switch from indirect to direct flights, and each avoids 200 kg CO₂ per trip, that results in:
10,000,000 x 200kg CO₂ = 2 million tonnes CO₂ saved annually
That’s a significant emissions saving, equivalent to taking nearly 1 million cars off the road (assuming ~2 tonnes CO₂ per car per year).
Will Heathrow’s Third Runway Still Increase Overall Emissions?
Even with these savings, it’s worth noting that a third runway increases total capacity, meaning:
- More flights overall (including new short-haul feeder routes)
- More aviation emissions, as total air traffic grows
- Indirect emissions from airport expansion and increased ground transport
However, compared to a scenario where Heathrow remains constrained and passengers continue flying via Europe, the third runway could be the lesser evil in terms of per-passenger emissions efficiency.
- Increasing long-haul capacity at Heathrow could reduce per-passenger emissions by cutting unnecessary short-haul connections to European hubs.
- Potential savings: ~2 million tonnes CO₂ per year**, if enough passengers switch to direct long-haul routes.
- However, **total aviation emissions will still rise**, since more flights will operate overall.
If emissions reduction is the primary goal, Heathrow’s third runway alone isn’t the silver bullet, but it can contribute to a more efficient aviation network by reducing indirect flight emissions. As well as completing the third runway as soon as possible, the government should stipulate that its use is confined to the latest generations of fuel efficient aircraft (e.g. Boeing 787, Airbus A350) which are about 25% more fuel-efficient than older models.
Hmm, I'm not convinced by the calculations How many connecting flights are being made that way because it's cheaper (vs. no direct flight being available)?
Let's say the additional flights carry 200 people each (which is a very conservative figure). So 52,000,000 additional passengers, and against that you have just 10,000,000 who are now taking direct flights. The net increase in emissions is surely huge (if my maths is correct)
Plus the impact of additional airport traffic, inc airport services, not to mention all the construction emissions.
I don't see how you can increase the number of flights from LHR without a significant increase in carbon footprint. Yes that's true for pretty much any economic activity (= 'growth'), but disproportionately so in the case of air travel expansion.
If you're only measuring flights from Heathrow then, of course, an increase in the number of flights will cause an increase in carbon emissions. But that's, of course, measuring the wrong thing.
If the total number of flights is brought down by the fact that more passengers can take direct flights (ie one, as opposed to two or more to reach their destination) then the carbon emissions will be reduced for those trips.
The point is "more flights from Heathrow" does not, necessarily mean "more flights".
I think you'll find that the underlying assumption is an expansion in air travel overall. As some have pointed out, population increase alone will push that, as will more mobile societies generally. If (big IF!) the goal of economic growthbis achieved that will hopefully mean some currently cash-strapped people would be able to afford holidays abroad.
Do we simply accept this trend, or try and.push back (in ways which will undoubtedly be unpopular with some, eg rationing numbers of flights per person/yesr, or hiking air taxes to levels which reduce demand)?
Not building a third runway at Heathrow will not decrease demand for air travel.
For sure, so you find other ways of reducing demand, or build and just carry on warming up the planet and concreting it over
Current Situation: Emissions from Connecting Flights
Currently, many UK passengers flying long-haul must first take a short-haul flight to a European hub (e.g., Amsterdam Schiphol, Paris Charles de Gaulle, Frankfurt) before continuing their journey. These connecting flights introduce additional fuel consumption, emissions, and inefficiencies due to:
- Extra takeoff and landing cycles, which are fuel-intensive
A short-haul flight from Heathrow to Amsterdam (Schiphol) emits approximately 80-100 kg CO₂ per passenger (for a Boeing 737-800/A320).
A long-haul flight from Schiphol to New York (JFK) emits around 1.5-2.0 tonnes CO₂ per passenger on a Boeing 787 or A350.
Adding those together:
- With a connection (LHR → AMS → JFK): 100 kg CO₂ (LHR-AMS) + 1,800 kg CO₂ (AMS-JFK) = 1.9 tonnes CO₂ per passenger
- With a direct Heathrow-JFK flight: 1.7 tonnes CO₂ per passenger
This suggests a potential saving of 200 kg CO₂ per passenger by avoiding the connection.
Estimating GHG Savings from Heathrow’s Third Runway
Heathrow’s third runway is expected to allow an increase in direct long-haul routes, which should reduce the number of passengers transiting via European hubs.
Estimated Passenger Shift
- The UK Department for Transport estimated that a third runway would add 260,000 additional flights per year (mostly long-haul).
- If even 10 million passengers per year switch from indirect to direct flights, and each avoids 200 kg CO₂ per trip, that results in:
10,000,000 x 200kg CO₂ = 2 million tonnes CO₂ saved annually
That’s a significant emissions saving, equivalent to taking nearly 1 million cars off the road (assuming ~2 tonnes CO₂ per car per year).
Will Heathrow’s Third Runway Still Increase Overall Emissions?
Even with these savings, it’s worth noting that a third runway increases total capacity, meaning:
- More flights overall (including new short-haul feeder routes)
- More aviation emissions, as total air traffic grows
- Indirect emissions from airport expansion and increased ground transport
However, compared to a scenario where Heathrow remains constrained and passengers continue flying via Europe, the third runway could be the lesser evil in terms of per-passenger emissions efficiency.
- Increasing long-haul capacity at Heathrow could reduce per-passenger emissions by cutting unnecessary short-haul connections to European hubs.
- Potential savings: ~2 million tonnes CO₂ per year**, if enough passengers switch to direct long-haul routes.
- However, **total aviation emissions will still rise**, since more flights will operate overall.
If emissions reduction is the primary goal, Heathrow’s third runway alone isn’t the silver bullet, but it can contribute to a more efficient aviation network by reducing indirect flight emissions. As well as completing the third runway as soon as possible, the government should stipulate that its use is confined to the latest generations of fuel efficient aircraft (e.g. Boeing 787, Airbus A350) which are about 25% more fuel-efficient than older models.
Hmm, I'm not convinced by the calculations How many connecting flights are being made that way because it's cheaper (vs. no direct flight being available)?
Let's say the additional flights carry 200 people each (which is a very conservative figure). So 52,000,000 additional passengers, and against that you have just 10,000,000 who are now taking direct flights. The net increase in emissions is surely huge (if my maths is correct)
Plus the impact of additional airport traffic, inc airport services, not to mention all the construction emissions.
I don't see how you can increase the number of flights from LHR without a significant increase in carbon footprint. Yes that's true for pretty much any economic activity (= 'growth'), but disproportionately so in the case of air travel expansion.
If you're only measuring flights from Heathrow then, of course, an increase in the number of flights will cause an increase in carbon emissions. But that's, of course, measuring the wrong thing.
If the total number of flights is brought down by the fact that more passengers can take direct flights (ie one, as opposed to two or more to reach their destination) then the carbon emissions will be reduced for those trips.
The point is "more flights from Heathrow" does not, necessarily mean "more flights".
I think you'll find that the underlying assumption is an expansion in air travel overall. As some have pointed out, population increase alone will push that, as will more mobile societies generally. If (big IF!) the goal of economic growthbis achieved that will hopefully mean some currently cash-strapped people would be able to afford holidays abroad.
Do we simply accept this trend, or try and.push back (in ways which will undoubtedly be unpopular with some, eg rationing numbers of flights per person/yesr, or hiking air taxes to levels which reduce demand)?
Not building a third runway at Heathrow will not decrease demand for air travel.
For sure, so you find other ways of reducing demand, or build and just carry on warming up the planet and concreting it over
Well, one way of reducing demand for flights is to make connecting flights less viable. That would mean meeting the demand for long-distance travel by making direct connecting flights available.
For example, if you want to fly from Heathrow to Montevideo (Uruguay), Quito (Ecuador) or Asuncion (Paraguay), you have to take a connecting flight.
For Montevideo you have to connect via Madrid, Sao Paulo, Rio or Buenos Aires. For Quito, you have to connect via Madrid, Bogota or Miami. And for Asuncion, you may have to connect via Madrid and Sao Paulo.
Given that take off and landing are the most carbon intensive parts of a flight, wouldn't it be better if passengers from London to these three countries were able to take one, direct flight, than having to take off and land four times to reach Montevideo or Quito and possibly six times to reach Asuncion?
So, if more direct-connect flights are available from Heathrow, the demand for the numbers of flights can be seen to be driven down, in each of these - and hundreds of other - cases. And the only way to achieve that is to increase capacity at Heathrow. And the only way to do that is... a third runway.
Current Situation: Emissions from Connecting Flights
Currently, many UK passengers flying long-haul must first take a short-haul flight to a European hub (e.g., Amsterdam Schiphol, Paris Charles de Gaulle, Frankfurt) before continuing their journey. These connecting flights introduce additional fuel consumption, emissions, and inefficiencies due to:
- Extra takeoff and landing cycles, which are fuel-intensive
A short-haul flight from Heathrow to Amsterdam (Schiphol) emits approximately 80-100 kg CO₂ per passenger (for a Boeing 737-800/A320).
A long-haul flight from Schiphol to New York (JFK) emits around 1.5-2.0 tonnes CO₂ per passenger on a Boeing 787 or A350.
Adding those together:
- With a connection (LHR → AMS → JFK): 100 kg CO₂ (LHR-AMS) + 1,800 kg CO₂ (AMS-JFK) = 1.9 tonnes CO₂ per passenger
- With a direct Heathrow-JFK flight: 1.7 tonnes CO₂ per passenger
This suggests a potential saving of 200 kg CO₂ per passenger by avoiding the connection.
Estimating GHG Savings from Heathrow’s Third Runway
Heathrow’s third runway is expected to allow an increase in direct long-haul routes, which should reduce the number of passengers transiting via European hubs.
Estimated Passenger Shift
- The UK Department for Transport estimated that a third runway would add 260,000 additional flights per year (mostly long-haul).
- If even 10 million passengers per year switch from indirect to direct flights, and each avoids 200 kg CO₂ per trip, that results in:
10,000,000 x 200kg CO₂ = 2 million tonnes CO₂ saved annually
That’s a significant emissions saving, equivalent to taking nearly 1 million cars off the road (assuming ~2 tonnes CO₂ per car per year).
Will Heathrow’s Third Runway Still Increase Overall Emissions?
Even with these savings, it’s worth noting that a third runway increases total capacity, meaning:
- More flights overall (including new short-haul feeder routes)
- More aviation emissions, as total air traffic grows
- Indirect emissions from airport expansion and increased ground transport
However, compared to a scenario where Heathrow remains constrained and passengers continue flying via Europe, the third runway could be the lesser evil in terms of per-passenger emissions efficiency.
- Increasing long-haul capacity at Heathrow could reduce per-passenger emissions by cutting unnecessary short-haul connections to European hubs.
- Potential savings: ~2 million tonnes CO₂ per year**, if enough passengers switch to direct long-haul routes.
- However, **total aviation emissions will still rise**, since more flights will operate overall.
If emissions reduction is the primary goal, Heathrow’s third runway alone isn’t the silver bullet, but it can contribute to a more efficient aviation network by reducing indirect flight emissions. As well as completing the third runway as soon as possible, the government should stipulate that its use is confined to the latest generations of fuel efficient aircraft (e.g. Boeing 787, Airbus A350) which are about 25% more fuel-efficient than older models.
Hmm, I'm not convinced by the calculations How many connecting flights are being made that way because it's cheaper (vs. no direct flight being available)?
Let's say the additional flights carry 200 people each (which is a very conservative figure). So 52,000,000 additional passengers, and against that you have just 10,000,000 who are now taking direct flights. The net increase in emissions is surely huge (if my maths is correct)
Plus the impact of additional airport traffic, inc airport services, not to mention all the construction emissions.
I don't see how you can increase the number of flights from LHR without a significant increase in carbon footprint. Yes that's true for pretty much any economic activity (= 'growth'), but disproportionately so in the case of air travel expansion.
If you're only measuring flights from Heathrow then, of course, an increase in the number of flights will cause an increase in carbon emissions. But that's, of course, measuring the wrong thing.
If the total number of flights is brought down by the fact that more passengers can take direct flights (ie one, as opposed to two or more to reach their destination) then the carbon emissions will be reduced for those trips.
The point is "more flights from Heathrow" does not, necessarily mean "more flights".
I think you'll find that the underlying assumption is an expansion in air travel overall. As some have pointed out, population increase alone will push that, as will more mobile societies generally. If (big IF!) the goal of economic growthbis achieved that will hopefully mean some currently cash-strapped people would be able to afford holidays abroad.
Do we simply accept this trend, or try and.push back (in ways which will undoubtedly be unpopular with some, eg rationing numbers of flights per person/yesr, or hiking air taxes to levels which reduce demand)?
Not building a third runway at Heathrow will not decrease demand for air travel.
But expanding Stansted would happen far more quickly and far less costly and not require the relocation of people and destruction of their homes Quite what the vested interests are in the logistically and legally prohibitive Heathrow daydream/nightmare boggles the mind
There would be plenty of tree hugging noise about concreting over some Green Belt but that's precisely the "blocking" NIMBYism the current mob are supposed to be sidestepping Bulldozing existing homes is a whole special kind of lunacy. None of which gets included in all that environmental guesswork/backofafagpacket/made up statistics
Current Situation: Emissions from Connecting Flights
Currently, many UK passengers flying long-haul must first take a short-haul flight to a European hub (e.g., Amsterdam Schiphol, Paris Charles de Gaulle, Frankfurt) before continuing their journey. These connecting flights introduce additional fuel consumption, emissions, and inefficiencies due to:
- Extra takeoff and landing cycles, which are fuel-intensive
A short-haul flight from Heathrow to Amsterdam (Schiphol) emits approximately 80-100 kg CO₂ per passenger (for a Boeing 737-800/A320).
A long-haul flight from Schiphol to New York (JFK) emits around 1.5-2.0 tonnes CO₂ per passenger on a Boeing 787 or A350.
Adding those together:
- With a connection (LHR → AMS → JFK): 100 kg CO₂ (LHR-AMS) + 1,800 kg CO₂ (AMS-JFK) = 1.9 tonnes CO₂ per passenger
- With a direct Heathrow-JFK flight: 1.7 tonnes CO₂ per passenger
This suggests a potential saving of 200 kg CO₂ per passenger by avoiding the connection.
Estimating GHG Savings from Heathrow’s Third Runway
Heathrow’s third runway is expected to allow an increase in direct long-haul routes, which should reduce the number of passengers transiting via European hubs.
Estimated Passenger Shift
- The UK Department for Transport estimated that a third runway would add 260,000 additional flights per year (mostly long-haul).
- If even 10 million passengers per year switch from indirect to direct flights, and each avoids 200 kg CO₂ per trip, that results in:
10,000,000 x 200kg CO₂ = 2 million tonnes CO₂ saved annually
That’s a significant emissions saving, equivalent to taking nearly 1 million cars off the road (assuming ~2 tonnes CO₂ per car per year).
Will Heathrow’s Third Runway Still Increase Overall Emissions?
Even with these savings, it’s worth noting that a third runway increases total capacity, meaning:
- More flights overall (including new short-haul feeder routes)
- More aviation emissions, as total air traffic grows
- Indirect emissions from airport expansion and increased ground transport
However, compared to a scenario where Heathrow remains constrained and passengers continue flying via Europe, the third runway could be the lesser evil in terms of per-passenger emissions efficiency.
- Increasing long-haul capacity at Heathrow could reduce per-passenger emissions by cutting unnecessary short-haul connections to European hubs.
- Potential savings: ~2 million tonnes CO₂ per year**, if enough passengers switch to direct long-haul routes.
- However, **total aviation emissions will still rise**, since more flights will operate overall.
If emissions reduction is the primary goal, Heathrow’s third runway alone isn’t the silver bullet, but it can contribute to a more efficient aviation network by reducing indirect flight emissions. As well as completing the third runway as soon as possible, the government should stipulate that its use is confined to the latest generations of fuel efficient aircraft (e.g. Boeing 787, Airbus A350) which are about 25% more fuel-efficient than older models.
Hmm, I'm not convinced by the calculations How many connecting flights are being made that way because it's cheaper (vs. no direct flight being available)?
Let's say the additional flights carry 200 people each (which is a very conservative figure). So 52,000,000 additional passengers, and against that you have just 10,000,000 who are now taking direct flights. The net increase in emissions is surely huge (if my maths is correct)
Plus the impact of additional airport traffic, inc airport services, not to mention all the construction emissions.
I don't see how you can increase the number of flights from LHR without a significant increase in carbon footprint. Yes that's true for pretty much any economic activity (= 'growth'), but disproportionately so in the case of air travel expansion.
If you're only measuring flights from Heathrow then, of course, an increase in the number of flights will cause an increase in carbon emissions. But that's, of course, measuring the wrong thing.
If the total number of flights is brought down by the fact that more passengers can take direct flights (ie one, as opposed to two or more to reach their destination) then the carbon emissions will be reduced for those trips.
The point is "more flights from Heathrow" does not, necessarily mean "more flights".
I think you'll find that the underlying assumption is an expansion in air travel overall. As some have pointed out, population increase alone will push that, as will more mobile societies generally. If (big IF!) the goal of economic growthbis achieved that will hopefully mean some currently cash-strapped people would be able to afford holidays abroad.
Do we simply accept this trend, or try and.push back (in ways which will undoubtedly be unpopular with some, eg rationing numbers of flights per person/yesr, or hiking air taxes to levels which reduce demand)?
Not building a third runway at Heathrow will not decrease demand for air travel.
But expanding Stansted would happen far more quickly and far less costly and not require the relocation of people and destruction of their homes Quite what the vested interests are in the logistically and legally prohibitive Heathrow daydream/nightmare boggles the mind
There would be plenty of tree hugging noise about concreting over some Green Belt but that's precisely the "blocking" NIMBYism the current mob are supposed to be sidestepping Bulldozing existing homes is a whole special kind of lunacy. None of which gets included in all that environmental guesswork/backofafagpacket/made up statistics
I am not saying that expanding Heathrow is better than expanding Stansted. I am saying that an expanded Heathrow could result in lower CO2 per passenger trip in future.
For what it's worth, I think Heathrow should remain as it is and Gatwick should have a second runway instead.
Taking the climate into account, I expect flying to become less popular as conditions deteriorate. My nephew recently returned from the states vowing never to fly again unless he has no other choice, after a particularly scary experience when landing during one of the more recent storms here.
I'm sure many will soon be thinking twice before choosing holiday destinations abroad now, factoring their choices tof destination to take account of the increased risk of extreme weather events, if they aren't doing so already that is. It's only going to get worse, according to the scientists.
Of course we should be trying to make the planes as safe as possible, and lowering their carbon emissions, but we haven't found a way yet to control the environment we inhabit without making it worse, so the flying conditions will get more challenging and more areas of the planet become higher risk.
Demand will drop off quite naturally over time without the need for other man made disincentives becoming necessary.
Current Situation: Emissions from Connecting Flights
Currently, many UK passengers flying long-haul must first take a short-haul flight to a European hub (e.g., Amsterdam Schiphol, Paris Charles de Gaulle, Frankfurt) before continuing their journey. These connecting flights introduce additional fuel consumption, emissions, and inefficiencies due to:
- Extra takeoff and landing cycles, which are fuel-intensive
A short-haul flight from Heathrow to Amsterdam (Schiphol) emits approximately 80-100 kg CO₂ per passenger (for a Boeing 737-800/A320).
A long-haul flight from Schiphol to New York (JFK) emits around 1.5-2.0 tonnes CO₂ per passenger on a Boeing 787 or A350.
Adding those together:
- With a connection (LHR → AMS → JFK): 100 kg CO₂ (LHR-AMS) + 1,800 kg CO₂ (AMS-JFK) = 1.9 tonnes CO₂ per passenger
- With a direct Heathrow-JFK flight: 1.7 tonnes CO₂ per passenger
This suggests a potential saving of 200 kg CO₂ per passenger by avoiding the connection.
Estimating GHG Savings from Heathrow’s Third Runway
Heathrow’s third runway is expected to allow an increase in direct long-haul routes, which should reduce the number of passengers transiting via European hubs.
Estimated Passenger Shift
- The UK Department for Transport estimated that a third runway would add 260,000 additional flights per year (mostly long-haul).
- If even 10 million passengers per year switch from indirect to direct flights, and each avoids 200 kg CO₂ per trip, that results in:
10,000,000 x 200kg CO₂ = 2 million tonnes CO₂ saved annually
That’s a significant emissions saving, equivalent to taking nearly 1 million cars off the road (assuming ~2 tonnes CO₂ per car per year).
Will Heathrow’s Third Runway Still Increase Overall Emissions?
Even with these savings, it’s worth noting that a third runway increases total capacity, meaning:
- More flights overall (including new short-haul feeder routes)
- More aviation emissions, as total air traffic grows
- Indirect emissions from airport expansion and increased ground transport
However, compared to a scenario where Heathrow remains constrained and passengers continue flying via Europe, the third runway could be the lesser evil in terms of per-passenger emissions efficiency.
- Increasing long-haul capacity at Heathrow could reduce per-passenger emissions by cutting unnecessary short-haul connections to European hubs.
- Potential savings: ~2 million tonnes CO₂ per year**, if enough passengers switch to direct long-haul routes.
- However, **total aviation emissions will still rise**, since more flights will operate overall.
If emissions reduction is the primary goal, Heathrow’s third runway alone isn’t the silver bullet, but it can contribute to a more efficient aviation network by reducing indirect flight emissions. As well as completing the third runway as soon as possible, the government should stipulate that its use is confined to the latest generations of fuel efficient aircraft (e.g. Boeing 787, Airbus A350) which are about 25% more fuel-efficient than older models.
Hmm, I'm not convinced by the calculations How many connecting flights are being made that way because it's cheaper (vs. no direct flight being available)?
Let's say the additional flights carry 200 people each (which is a very conservative figure). So 52,000,000 additional passengers, and against that you have just 10,000,000 who are now taking direct flights. The net increase in emissions is surely huge (if my maths is correct)
Plus the impact of additional airport traffic, inc airport services, not to mention all the construction emissions.
I don't see how you can increase the number of flights from LHR without a significant increase in carbon footprint. Yes that's true for pretty much any economic activity (= 'growth'), but disproportionately so in the case of air travel expansion.
If you're only measuring flights from Heathrow then, of course, an increase in the number of flights will cause an increase in carbon emissions. But that's, of course, measuring the wrong thing.
If the total number of flights is brought down by the fact that more passengers can take direct flights (ie one, as opposed to two or more to reach their destination) then the carbon emissions will be reduced for those trips.
The point is "more flights from Heathrow" does not, necessarily mean "more flights".
I think you'll find that the underlying assumption is an expansion in air travel overall. As some have pointed out, population increase alone will push that, as will more mobile societies generally. If (big IF!) the goal of economic growthbis achieved that will hopefully mean some currently cash-strapped people would be able to afford holidays abroad.
Do we simply accept this trend, or try and.push back (in ways which will undoubtedly be unpopular with some, eg rationing numbers of flights per person/yesr, or hiking air taxes to levels which reduce demand)?
Not building a third runway at Heathrow will not decrease demand for air travel.
But expanding Stansted would happen far more quickly and far less costly and not require the relocation of people and destruction of their homes Quite what the vested interests are in the logistically and legally prohibitive Heathrow daydream/nightmare boggles the mind
There would be plenty of tree hugging noise about concreting over some Green Belt but that's precisely the "blocking" NIMBYism the current mob are supposed to be sidestepping Bulldozing existing homes is a whole special kind of lunacy. None of which gets included in all that environmental guesswork/backofafagpacket/made up statistics
I am not saying that expanding Heathrow is better than expanding Stansted. I am saying that an expanded Heathrow could result in lower CO2 per passenger trip in future.
For what it's worth, I think Heathrow should remain as it is and Gatwick should have a second runway instead.
Given Heathrow is already a very busy airport and that it’s got a rail and tube network that handles a lot of passenger traffic getting to and from the airport then it’s the natural and probably most ‘green’ option.
for when it’s worth I’d add additional runways to Gatwick, Luton and any other regional airport that can justify it commercially and is conveniently accessible by public transport.
I am sure today's news of a helicopter crashing into a passenger aircraft over Washington DC will put more people off flying. RIP to those who lost their lives. (Eight days ago, the President of the United States fired 400 Federal Aviation Administration senior officials, the Transportation Security Administration head and 3,000 air traffic controllers, apparently. Perhaps that needs reviewing).
The thing about aviation and greenhouse gas emissions is that the total amount of GHG emissions is what is important. So, everything that can be done to reduce that should be; while, at the same time understanding that the demand for flights will continue to increase, unabated, unless there's another once-in-a-century issue like Covid. People are going to continue to fly. It's the cheapest, quickest, easiest, most efficient way to travel long distances in most cases.
Some countries and regions have a geopolitical advantage when it comes to alternative modes. When you can travel between two cities by train in 3.5 hours, train passengers represent 50% of the combined rail and aircraft passenger numbers. Typically if you can get there in less than 3.5 hours, trains take more than 50%; more than 3.5 hours, they take less than 50%. I would react to this by mandating that a heavy tax is applied to any flight route that can be taken in less than 3.5 hours by train. That way, we can shift people off aircraft - thereby reducing carbon emissions - on key routes like London-Paris; London-Brussels; Rome-Milan; Paris-Amsterdam; Paris-Brussels; Brussels-Amsterdam; Milan-Zurich; Barcelona-Lyon; Vienna-Munich; Cologne-Amsterdam. Shifting passengers from aircraft to trains on these routes would reduce air traffic in Europe by about 200 flights a day. Between 1.5 million and 2.4 million metric tonnes of CO2 would then be taken out of the total aviation carbon emissions.
Airlines, airports and aircraft manufacturers are all racing each other to develop more sustainable aviation fuels. (I'm working with one company who is managing the creation of a farm in Japan that grows algae in seawater. Totally sustainable. And the algae is turned into aviation fuel. It's not using up any farming land, it's as low-carbon as you could possibly imagine and, most importantly... it works!)
And aircraft manufacturers are competing with each other (with Boeing and Airbus at the forefront) to create ever-more fuel efficient (and therefore lower emission) aircraft.
We can't cut aviation emissions by hoping people will stop wanting to fly. But we can still do an awful lot by enabling those people who do travel to do so in ever-more responsible ways.
I am sure today's news of a helicopter crashing into a passenger aircraft over Washington DC will put more people off flying. RIP to those who lost their lives. (Eight days ago, the President of the United States fired 400 Federal Aviation Administration senior officials, the Transportation Security Administration head and 3,000 air traffic controllers, apparently. Perhaps that needs reviewing).
The thing about aviation and greenhouse gas emissions is that the total amount of GHG emissions is what is important. So, everything that can be done to reduce that should be; while, at the same time understanding that the demand for flights will continue to increase, unabated, unless there's another once-in-a-century issue like Covid. People are going to continue to fly. It's the cheapest, quickest, easiest, most efficient way to travel long distances in most cases.
Some countries and regions have a geopolitical advantage when it comes to alternative modes. When you can travel between two cities by train in 3.5 hours, train passengers represent 50% of the combined rail and aircraft passenger numbers. Typically if you can get there in less than 3.5 hours, trains take more than 50%; more than 3.5 hours, they take less than 50%. I would react to this by mandating that a heavy tax is applied to any flight route that can be taken in less than 3.5 hours by train. That way, we can shift people off aircraft - thereby reducing carbon emissions - on key routes like London-Paris; London-Brussels; Rome-Milan; Paris-Amsterdam; Paris-Brussels; Brussels-Amsterdam; Milan-Zurich; Barcelona-Lyon; Vienna-Munich; Cologne-Amsterdam. Shifting passengers from aircraft to trains on these routes would reduce air traffic in Europe by about 200 flights a day. Between 1.5 million and 2.4 million metric tonnes of CO2 would then be taken out of the total aviation carbon emissions.
Airlines, airports and aircraft manufacturers are all racing each other to develop more sustainable aviation fuels. (I'm working with one company who is managing the creation of a farm in Japan that grows algae in seawater. Totally sustainable. And the algae is turned into aviation fuel. It's not using up any farming land, it's as low-carbon as you could possibly imagine and, most importantly... it works!)
And aircraft manufacturers are competing with each other (with Boeing and Airbus at the forefront) to create ever-more fuel efficient (and therefore lower emission) aircraft.
We can't cut aviation emissions by hoping people will stop wanting to fly. But we can still do an awful lot by enabling those people who do travel to do so in ever-more responsible ways.
I am sure today's news of a helicopter crashing into a passenger aircraft over Washington DC will put more people off flying. RIP to those who lost their lives. (Eight days ago, the President of the United States fired 400 Federal Aviation Administration senior officials, the Transportation Security Administration head and 3,000 air traffic controllers, apparently. Perhaps that needs reviewing).
The thing about aviation and greenhouse gas emissions is that the total amount of GHG emissions is what is important. So, everything that can be done to reduce that should be; while, at the same time understanding that the demand for flights will continue to increase, unabated, unless there's another once-in-a-century issue like Covid. People are going to continue to fly. It's the cheapest, quickest, easiest, most efficient way to travel long distances in most cases.
Some countries and regions have a geopolitical advantage when it comes to alternative modes. When you can travel between two cities by train in 3.5 hours, train passengers represent 50% of the combined rail and aircraft passenger numbers. Typically if you can get there in less than 3.5 hours, trains take more than 50%; more than 3.5 hours, they take less than 50%. I would react to this by mandating that a heavy tax is applied to any flight route that can be taken in less than 3.5 hours by train. That way, we can shift people off aircraft - thereby reducing carbon emissions - on key routes like London-Paris; London-Brussels; Rome-Milan; Paris-Amsterdam; Paris-Brussels; Brussels-Amsterdam; Milan-Zurich; Barcelona-Lyon; Vienna-Munich; Cologne-Amsterdam. Shifting passengers from aircraft to trains on these routes would reduce air traffic in Europe by about 200 flights a day. Between 1.5 million and 2.4 million metric tonnes of CO2 would then be taken out of the total aviation carbon emissions.
Airlines, airports and aircraft manufacturers are all racing each other to develop more sustainable aviation fuels. (I'm working with one company who is managing the creation of a farm in Japan that grows algae in seawater. Totally sustainable. And the algae is turned into aviation fuel. It's not using up any farming land, it's as low-carbon as you could possibly imagine and, most importantly... it works!)
And aircraft manufacturers are competing with each other (with Boeing and Airbus at the forefront) to create ever-more fuel efficient (and therefore lower emission) aircraft.
We can't cut aviation emissions by hoping people will stop wanting to fly. But we can still do an awful lot by enabling those people who do travel to do so in ever-more responsible ways.
I think those claims on 3000 sacked is scaremongering. I can’t see any evidence of that from a credible source and would have been all over the news if true.
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Once we understand that, then the task must be how we ameliorate the climate effects of air travel. That's by ensuring all flights - or, as many as possible, are undertaken via routes and modes that are as efficient as possible. That's by ensuring flights are operated at the lowest cost per passenger in terms of emissions; by ensuring flights between cities that can be reached in reasonable time by a cleaner mode should be banned; and by ensuring investment and incentives in the cleanest aircraft and the most sustainable fuels.
If we want to combat greenhouse gas emissions by crossing our fingers and hoping people decide to stop flying, we will fail, quickly and completely.
More house building
More hospitals
More Doctors surgeries
More Schools
More Roads
More Demand for gas and electricity
More Demand for food
And unfortunately More Flights.
With the UK population predicted to increase by several million over the next decade I'm afraid it comes without it's problems.
We were advised in 2020 that we needed to halve emissions globally by the end of the decade, and with the exception of the COVID year, when flights were grounded with it treated as an emergency, they've been increasing year on year since.
Climate change isn't being treated as an emergency. Economic growth takes precedence over environmental concerns, and trying to discredit or silence those sounding the alarm is more important than trying to put out the fire.
Is the announcement today a sign of giving up on climate objectives, an acceptance that it's probably too late now anyway and we should all make hay whilst the sun shines? And is it really possible to grow economies worldwide, with growing populations, in a way that doesn't destabilize the balance of nature and climate?
Looks like I picked the wrong week to stop posting 🤣
*This was several years ago, when people could actually go to hospitals.
Let's say the additional flights carry 200 people each (which is a very conservative figure). So 52,000,000 additional passengers, and against that you have just 10,000,000 who are now taking direct flights. The net increase in emissions is surely huge (if my maths is correct)
Plus the impact of additional airport traffic, inc airport services, not to mention all the construction emissions.
I don't see how you can increase the number of flights from LHR without a significant increase in carbon footprint. Yes that's true for pretty much any economic activity (= 'growth'), but disproportionately so in the case of air travel expansion.
https://en.m.wikipedia.org/wiki/Jevons_paradox
If the total number of flights is brought down by the fact that more passengers can take direct flights (ie one, as opposed to two or more to reach their destination) then the carbon emissions will be reduced for those trips.
The point is "more flights from Heathrow" does not, necessarily mean "more flights".
My money is on that happening inside your ten year timescale.
A third runway at Heathrow will increase greenhouse gas emissions significantly and have a devastating effect on biodiversity, air and noise pollution. To suggest otherwise is laughable and arguments about fewer flights elsewhere won't wash with environmentalists.
By sending the appalling message that we aren't taking our net zero targets seriously though, it might actually be a good thing for increasing awareness of the climate crisis we're in. It will bring environmentalists together in mass opposition around a single issue, the project likely to be being hampered by protests getting broad media coverage, so those on board with it can expect a very bumpy ride!
It's a difficult one as currently I want to be disincentivising flying and would be taxing it additionally. But if we are confident a carbon neutral way of flying can be delivered then we don't want to hold back infrastructure and future growth (despite my views on this being a terrible metric by which to measure an economy and society) by not building now.
If it was up to me I would say build it but at the same time would be taxing frequent flyers and taxing aviation fuel greater and massively taxing private jets. All under the polluter pays principle and in order to incentivise the development of whatever fuel is the future of air travel.
Besides, by ditching kerosine and going for electric planes, you're just ditching one unsustainable aircraft for another. Hydrogen fuel can be artificially made and is obviously the future.
Do we simply accept this trend, or try and.push back (in ways which will undoubtedly be unpopular with some, eg rationing numbers of flights per person/yesr, or hiking air taxes to levels which reduce demand)?
For example, if you want to fly from Heathrow to Montevideo (Uruguay), Quito (Ecuador) or Asuncion (Paraguay), you have to take a connecting flight.
For Montevideo you have to connect via Madrid, Sao Paulo, Rio or Buenos Aires. For Quito, you have to connect via Madrid, Bogota or Miami. And for Asuncion, you may have to connect via Madrid and Sao Paulo.
Given that take off and landing are the most carbon intensive parts of a flight, wouldn't it be better if passengers from London to these three countries were able to take one, direct flight, than having to take off and land four times to reach Montevideo or Quito and possibly six times to reach Asuncion?
So, if more direct-connect flights are available from Heathrow, the demand for the numbers of flights can be seen to be driven down, in each of these - and hundreds of other - cases. And the only way to achieve that is to increase capacity at Heathrow. And the only way to do that is... a third runway.
Quite what the vested interests are in the logistically and legally prohibitive Heathrow daydream/nightmare boggles the mind
There would be plenty of tree hugging noise about concreting over some Green Belt but that's precisely the "blocking" NIMBYism the current mob are supposed to be sidestepping
Bulldozing existing homes is a whole special kind of lunacy. None of which gets included in all that environmental guesswork/backofafagpacket/made up statistics
For what it's worth, I think Heathrow should remain as it is and Gatwick should have a second runway instead.
I'm sure many will soon be thinking twice before choosing holiday destinations abroad now, factoring their choices tof destination to take account of the increased risk of extreme weather events, if they aren't doing so already that is. It's only going to get worse, according to the scientists.
Of course we should be trying to make the planes as safe as possible, and lowering their carbon emissions, but we haven't found a way yet to control the environment we inhabit without making it worse, so the flying conditions will get more challenging and more areas of the planet become higher risk.
Demand will drop off quite naturally over time without the need for other man made disincentives becoming necessary.
https://www.climatecentral.org/climate-matters/climate-change-is-disrupting-air-travel-2023
for when it’s worth I’d add additional runways to Gatwick, Luton and any other regional airport that can justify it commercially and is conveniently accessible by public transport.
The thing about aviation and greenhouse gas emissions is that the total amount of GHG emissions is what is important. So, everything that can be done to reduce that should be; while, at the same time understanding that the demand for flights will continue to increase, unabated, unless there's another once-in-a-century issue like Covid. People are going to continue to fly. It's the cheapest, quickest, easiest, most efficient way to travel long distances in most cases.
Some countries and regions have a geopolitical advantage when it comes to alternative modes. When you can travel between two cities by train in 3.5 hours, train passengers represent 50% of the combined rail and aircraft passenger numbers. Typically if you can get there in less than 3.5 hours, trains take more than 50%; more than 3.5 hours, they take less than 50%. I would react to this by mandating that a heavy tax is applied to any flight route that can be taken in less than 3.5 hours by train. That way, we can shift people off aircraft - thereby reducing carbon emissions - on key routes like London-Paris; London-Brussels; Rome-Milan; Paris-Amsterdam; Paris-Brussels; Brussels-Amsterdam; Milan-Zurich; Barcelona-Lyon; Vienna-Munich; Cologne-Amsterdam. Shifting passengers from aircraft to trains on these routes would reduce air traffic in Europe by about 200 flights a day. Between 1.5 million and 2.4 million metric tonnes of CO2 would then be taken out of the total aviation carbon emissions.
Airlines, airports and aircraft manufacturers are all racing each other to develop more sustainable aviation fuels. (I'm working with one company who is managing the creation of a farm in Japan that grows algae in seawater. Totally sustainable. And the algae is turned into aviation fuel. It's not using up any farming land, it's as low-carbon as you could possibly imagine and, most importantly... it works!)
And aircraft manufacturers are competing with each other (with Boeing and Airbus at the forefront) to create ever-more fuel efficient (and therefore lower emission) aircraft.
We can't cut aviation emissions by hoping people will stop wanting to fly. But we can still do an awful lot by enabling those people who do travel to do so in ever-more responsible ways.