A few weeks ago I was speaking to my MP about the expansion of Luton airport. In an age of climate crisis, how can we continue to drive expansion of such a major source of pollution? At a time when we need to be decarbonising the entire economy, Luton Airport is one of the fastest growing sources of greenhouse gases in the country.
The answer, which we had from both our Luton MPs, is that planes in future will be more efficient. Every generation of planes is 30% more efficient than the last. So that proposed growth in airport capacity doesn’t have to mean an increase in CO2 emissions.
Since this is a common answer that I have also heard from the council and from friends who work at the airport, it is worth examining. First, it is true that planes are getting more efficient:
A scan of the history of commercial passenger planes shows rapid improvement in the early days, followed by slower but consistent improvements in the amount of energy needed per passenger mile. There are further efficiency savings to be had, some theoretical, some definitely on their way. There are reasons to question whether that new generation of planes will make a difference in time, but the bigger issue is whether those efficiencies will offset the growth.
Here we get into the basic conundrum of any decarbonisation strategy that assumes ongoing growth – and of course that’s almost all of them. Governments and businesses want to grow and cut carbon at the same time, and to do that they rely on decoupling: breaking the link between economic growth and rising emissions.
As I’ve described in more detail in previous posts, this only works if you get absolute rather than relative decoupling. It sounds a bit technical, but it’s common sense really. If the economy is getting 2% more efficient every year, but also growing by 3% a year, then emissions will keep rising. This is relative decoupling, and it’s the problem with aviation expansion.
Luton Airport is relying on a fleet of theoretical planes that will be 30% more efficient. But the plan is for the airport to double in size. It doesn’t take a mathematician to work out that even if those more efficient planes materialise, the growth will overtake the efficiency gains. Emissions will still rise.
Right now, every source of emissions needs to be falling. No sector gets a free pass to keep growing its carbon emissions. Luton Airport’s plans are called a ‘vision for sustainable growth‘, but from a climate change point of view that’s an oxymoron. It cannot be sustainable, and also expanding. It will have to pick one or the other.