The Uncertain Future of Electric Planes
In my previous post, I outlined how supersonic planes might be a commercial reality by the end of the decade. Another exciting aviation development is also nearing commercial deployment — electric planes.
I will be focusing on electric passenger planes, and not eVTOL (electric vertical take-off and landing) aircrafts. These are much shorter in range (often described as air taxis) and deserve their own post.
Planes are hardly eco-friendly. As the graph below shows, short-haul flights are the worst offenders (planes burn a disproportionate amount of fuel during takeoff and climb, hence the difference between short-haul and long-haul flights).
Besides converting people to more eco-friendly transport modes, decreasing the emission of planes is the logical second option to lessen the industry’s impact on the environment. Most of the focus is currently on Sustainable Aviation Fuel (SAF), which is non-fossil-derived aviation fuel. IATA has a great explainer on SAF. These fuels, often biofuels, offer lower emissions while being compatible with existing plane fuel systems.
Another option is electric passenger planes. These promise lower emissions, but also lower operating and maintenance costs. Needless to say, startups and airlines have noticed.
Current battery technology doesn’t allow for long-range flights, and likely won’t do so anytime soon. The batteries required for a trans-Atlantic flight would simply be too heavy. This relates to energy density — the “amount of energy that can be stored in a given system, substance, or region of space”. Every pound of jet fuel delivers 14 times the power of a pound of battery. Another advantage of fuel is that it burns off during flight, making the plane lighter — not so with batteries.
However, on short-haul flights, electric planes can work, in theory at least.
One startup trying to prove this is Heart Aerospace. Their main plane in development is the ES-19. The plane will carry 19 passengers, with a range of 250 miles (400 kilometres). The company claims it will recharge for its average flight in 40 minutes. The first ES-19 is set to be delivered by 2026. Last year, the company announced their $35 million Series A, as well as an order of 200 planes from United and Mesa Airlines. Finnair also signed a letter of intent for 20 of its planes.
The E-19’s specifications make it ideal for feeder flights to bigger hubs. United plans to use them on over 100 of its regional flights. Heart Aerospace estimates that their planes cost 90% less to maintain than turboprops, and they decrease fuel costs by 50–75%.
The largest electric passenger plane currently being developed is the Wright Spirit, which aims to be used for commercial flights by 2026. Wright is retrofitting BAe 146s, a plane produced between 1983 and 2001 in the UK by British Aerospace, later part of BAE Systems. By retrofitting an existing plane, it cuts costs, production and approval times.
The plane will carry 100 passengers and have a range of 460 miles (700 kilometres). From a commercial point of view, Wright markets its plane to airline partners as ideal for 1-hour flights between busy cities, like the routes outlined below:
However, the Spirit plane is only one step towards Wright’s longer-term goal — the Wright 1. The Wright 1 will carry 186 passengers, and have a range of 800 miles (1 300 kilometres). Both EasyJet and Viva Aerobus have partnered with Wright to operate the Wright 1 once completed, which Wright hopes to be by 2030.
Perhaps closest to commercial deployment is the Alice plane, developed by Eviation in Israel. The plane has a range of 440 nautical miles (815 kilometres). It will be offered in three varieties — Commuter or Executive which will carry 9 and 6 passengers respectively, or a cargo-only model. CapeAir, a US-based commuter airline, has signed a letter of intent for 76 Alice models, which should be ready for flight next year.
Larger aviation companies are also funding and developing electric planes and their associated technology. Last year, NASA awarded $179 million to General Electric Aviation and $74 million to MagniX USA in order for the two companies to prove the feasibility of their Electrified Aircraft Propulsion (EAP) technologies. This is part of NASA’s eventual aim to “introduce EAP technologies to U.S. aviation fleets no later than 2035, supporting short-range and regional commercial air travel, as well as single-aisle seat transports.”
Electric planes aren’t without their sceptics. Some experts calculate that the current battery technology can’t possibly produce the ranges claimed by some of the startups mentioned above. Jayant Mukhopadhaya, a transportation analyst at the International Council on Clean Transportation (ICCT) estimated that based on current battery technology, Heart Aerospace’s ES-19 would have a range of only 160 miles (260 kilometres) — significantly less than the 250 miles (400 kilometres) claimed.
Another key consideration for electric planes is the reserve requirement. Planes are by law required to carry enough fuel (or battery power) to circle an airport for 30 minutes in case they can’t land right away, and they must also have enough power to reach an alternative airport 100 km (60 miles) away in case it can’t land at the intended airport (this varies slightly between countries). According to Andreas Schafer, director of the air transportation systems lab at University College London, this reserve requirement is “ultimately the killer.”
According to MIT Technology Review, when you take the reserve requirement into account, “the usable range of a 19-seat plane goes from about 160 miles to about 30 miles. For a larger aircraft like the 100-seat planes that Wright is building, it’s less than six miles”.
As climate regulations become stricter, electric planes can play a role in reducing emissions on short-haul routes. How much the battery technology needs to be improved before this can happen, and whether some startups are further along than we know, will be a vital factor over the following few years.
Thanks to Brandon Coetzer and Karel van der Vyver for edits and suggestions!
