Slow it may be, but the transition to electric vehicles is now well underway, with the promise of substantial reductions in greenhouse gases to come. Someone asked me recently if a similar transition was possible in aviation – will we ever have electric planes?
The usual answer is no, not any time soon. Getting a plane airborne takes a huge amount of energy, and only fossil fuels can deliver enough power for their weight. Half the weight of a loaded 747 is jet fuel, which is bad enough. If you were to try and get the same amount of thrust from batteries, you’d be looking at a weight dozens of times greater than the plane itself. It wouldn’t get off the ground.
That’s the usual answer. But it’s not the whole story.
For one thing, electric planes already exist, so they’re clearly not impossible. It just depends what you’re expecting them to do. Take the Extra 330LE, a two-seater electric stunt plane for zero emissions airshows. The trade-off? It only needs to run for 20 minutes at a time.
Or the Taurus G4, from Slovenian company Pipistrel. This four passenger plane won a NASA prize in 2011 for the most efficient flight over a 200 mile distance. But that is as far as it can go, at a cruising speed of 100 miles per hour. It looks and behaves more like a glider and it was only built to demonstrate the technology.
More famously, Solar Impulse 2 completed a round-the-world flight last year, breaking a series of records along the way. A remarkable machine, the trade-off for its incredible performance is the enormous wingspan. This is “an airplane of the size of a 747 with the weight of a car”. That’s fine for unmanned vehicles that need to stay in the air for a long time, but it’s not practical for transport.
Perhaps a better question is will the likes of you and I ever fly in an electric plane? Will we ever have electric passenger planes, and carbon-free budget airlines?
A few years ago it would have been a definitive no. Today it’s a more of a cautious ‘eventually’. There are several companies putting serious research funding into it, knowing that as the sophistication of batteries and motors advances, a time will come when it should be possible. We’re a way off yet, but it can be planned for.
One of those working on it is NASA, who have re-launched their X-Plane research programme with a ten-year electric plane project. The current prototype is the X-57, which will take off with 14 motors and then fly with two. It’s the first of a series of progressively larger planes NASA plan to build and test.
Airbus know the future lies this way too, and they have a long term research plan as well. The goal is “silent, CO2 free flight”, and a new research hub will open in Munich in 2018.
Airbus are looking at hybrid aviation for longer distances, and so are Boeing. The latter’s vision is to build a plane that burns jet fuel on take-off and then switches to electric once at altitude. That should deliver fuel savings of 70% on conventional aircraft.
The two big beasts have competition. It won’t surprise you to know that there are start-ups promising low carbon aviation. Zunum Aero is a new company that is focusing on short-haul passenger services. They intend to work with upgradeable batteries so that as battery technology improves, so will the range of the planes. Wright Electric is another. Like many start-ups, it has a website with a bold mission and zero detail. “Wright Electric’s goal is for every short flight to be electric within 20 years” they say, and invite you to sign up to their newsletter.
Aviation being what it is, we can expect these hybrid planes in 2035 or so. That’s just how long it takes. Development for Boeing’s 787 Dreamliner began in the late 90s and it flew its first commercial flight in 2011. Aircraft can last for 30 or 40 years, so it will take another 20 years for them to get established enough to make a dent in the world’s airline fleets.
In short, I expect we will eventually have hybrid and then electric planes, and a new era of low carbon aviation. We won’t get it fast enough to make a big contribution to the fight against climate change, so there’s still no substitute for reducing the number of flights we take right now. But we don’t need to give up all hope of international travel in the longer term. Maybe I’ll be able to enjoy flying again by the time I retire.