Electric planes might seem futuristic, but they aren’t that far off, at least for short hops.
Two-seater Velis Electros are already quietly buzzing around Europe, electric sea planes are being tested in British Columbia, and larger planes are coming. Air Canada announced on Sept. 15, 2022, that it would buy 30 electric-hybrid regional aircraft from Sweden’s Heart Aerospace, which expects to have its 30-seat plane in service by 2028. Analysts at the U.S. National Renewable Energy Lab note that the first hybrid electric 50- to 70-seat commuter plane could be ready not long after that. In the 2030s, they say, electric aviation could really take off.
That matters for managing climate change. About 3% of global emissions come from aviation today, and with more passengers and flights expected as the population expands, aviation could be producing three to five times more carbon dioxide emissions by 2050 than it did before the COVID-19 pandemic.
Aerospace engineer and assistant professor Gökçin Çınar develops sustainable aviation concepts, including hybrid-electric planes and hydrogen fuel alternatives, at the University of Michigan. We asked her about the key ways to cut aviation emissions today and where technologies like electrification and hydrogen are headed.
Why is aviation so difficult to electrify?
Aircraft are some of the most complex vehicles out there, but the biggest problem for electrifying them is the battery weight.
If you tried to fully electrify a 737 with today’s batteries, you would have to take out all the passengers and cargo and fill that space with batteries just to fly for under an hour.
Jet fuel can hold about 50 times more energy compared to batteries per unit mass. So, you can have 1 pound of jet fuel or 50 pounds of batteries. To close that gap, we need to either make lithium-ion batteries lighter or develop new batteries that hold more energy. New batteries are being developed, but they aren’t yet ready for aircraft.
Air Canada and United Airlines have ordered 30-seat regional hybrid-electric planes from Heart Aerospace that can go about 125 miles (200 km) fully electric and 250 miles (400 km) as hybrids. With a 25-passenger configuration, the company says the hybrid distance doubles. Heart Aerospace
Even though we might not be able to fully electrify a 737, we can get some fuel burn benefits from batteries in the larger jets by using hybrid propulsion systems. We are trying to make that happen in the short term, with a 2030-2035 target for smaller regional planes. The less fuel burned during flight, the fewer greenhouse gas emissions.
How does hybrid aviation work to cut emissions?
Hybrid electric aircraft are similar to hybrid electric cars in that they use a combination of batteries and aviation fuels. The problem is that no other industry has the weight limitations that we do in the aerospace industry.
That’s why we have to be very smart about how and how much we are hybridizing the propulsion system.
Using batteries as a power assist during takeoff and climb are very promising options. Taxiing to the runway using just electric power could also save a significant amount of fuel and reduce the local emissions at airports. There is a sweet spot between the added weight of the battery and how much electricity you can use to get net fuel benefits. This optimization problem is at the center of my research.
Hybrids would still burn fuel during flight, but it could be considerably less than just relying entirely on jet fuel.
How hybrid electric aviation could work on large aircraft.
I see hybridization as a mid-term option for larger jets, but a near-term solution for regional aircraft.
For 2030 to 2035, we’re focused on hybrid turboprops, typically regional aircraft with 50-80 passengers or used for freight. These hybrids could cut fuel use by about 10%.
With electric hybrids, airlines could also make more use of regional airports, reducing congestion and time larger planes spend idling on the runway.
What do you expect to see in the near term from sustainable aviation?
Shorter term we’ll see more use of sustainable aviation fuels, or SAF. With today’s engines, you can dump sustainable aviation fuel into the same fuel tank and burn it. Fuels made from corn, oilseeds, algae and other fats are already being used.
Sustainable aviation fuels can reduce an aircraft’s net carbon dioxide emissions by around 80%, but supply is limited, and using more biomass for fuel could compete with food production and lead to deforestation.
A second option is using synthetic sustainable aviation fuels, which involves capturing carbon from the air or other industrial processes and synthesizing it with hydrogen. But that’s a complex and costly process and does not have a high production scale yet.
Ampaire reported that its hybrid electric EEL had fuel savings up to 40% compared with a standard version of the similar Cessna Skymaster. Ampaire
Airlines can also optimize their operations in the short term, such as route planning to avoid flying nearly empty planes. That can also reduce emissions.
Is hydrogen an option for aviation?
Hydrogen fuel has been around a very long time, and when it’s green hydrogen — produced with water and electrolysis powered by renewable energy — it doesn’t produce carbon dioxide. It can also hold more energy per unit of mass than batteries.
There are two ways to use hydrogen in an airplane: either in place of regular jet fuel in an engine, or combined with oxygen to power hydrogen fuel cells, which then generate electricity to power the aircraft.
The problem is volume — hydrogen gas takes up a lot of space. That’s why engineers are looking at methods like keeping it very cool so it can be stored as liquid until it’s burned as a gas. It still takes up more space than jet fuel, and the storage tanks are heavy, so how to store, handle or distribute it on aircraft is still being worked out.
Due to the variety of options, I see hydrogen as one of the key technologies for sustainable aviation.
Will these technologies be able to meet the aviation industry’s goals for reducing emissions?
The problem with aviation emissions isn’t their current levels — it’s the fear that their emissions will increase rapidly as demand increases. By 2050, we could see three to five times more carbon dioxide emissions from aviation than before the pandemic.
The International Civil Aviation Organization, a United Nations agency, generally defines the industry’s goals, looking at what’s feasible and how aviation can push the boundaries.
Its long-term goal is to cut net carbon dioxide emissions 50% by 2050 compared with 2005 levels. Getting there will require a mix of different technologies and optimization. I don’t know if we’re going to be able to reach it by 2050, but I believe we must do everything we can to make future aviation environmentally sustainable.
Gökçin Çınar receives research funding from the government and other entities to work on sustainable aviation technologies.
This article is republished from The Conversation under a Creative Commons license.
Electric planes are coming: Short-hop regional flights could run on batteries soon
Stacey Wescott/Chicago Tribune/TNS
The Fort Worth-based airline will automatically search for seats together the day before departure if a family is traveling with children under 15 and if they do not already have seats assigned, according to the airline’s policy. If seats are limited, American will assign children seats next to at least one accompanying adult.
“It’s important all children are part of the same reservation as the parent(s) so our system recognizes that they are traveling together,” according to airline policy.
American advises people to arrive early and bring any required travel documents as you may have to provide proof of age for children under 18.
While at the boarding gate, families with children under 2 years old can ask to board early. Children older than 2 require their own tickets, and children under 5 cannot travel alone. Infants, or children under 2 years old, can travel at no additional cost on the lap of a parent.
Additionally, only one diaper bag is allowed per child. For more information about American Airlines policy, click here.
Stacey Wescott/Chicago Tribune/TNS
The Fort Worth-based airline will automatically search for seats together the day before departure if a family is traveling with children under 15 and if they do not already have seats assigned, according to the airline’s policy. If seats are limited, American will assign children seats next to at least one accompanying adult.
“It’s important all children are part of the same reservation as the parent(s) so our system recognizes that they are traveling together,” according to airline policy.
American advises people to arrive early and bring any required travel documents as you may have to provide proof of age for children under 18.
While at the boarding gate, families with children under 2 years old can ask to board early. Children older than 2 require their own tickets, and children under 5 cannot travel alone. Infants, or children under 2 years old, can travel at no additional cost on the lap of a parent.
Additionally, only one diaper bag is allowed per child. For more information about American Airlines policy, click here.
Dallas-based Southwest Airlines famously operates on an open seating basis, allowing passengers to pick their seats when boarding the aircraft.
“Open seating provides a great opportunity for families or groups traveling together to sit together on the aircraft,” Southwest spokesman Chris Perry said. “Customers traveling on the same reservation receive boarding positions adjacent to one another upon check-in.”
The airline’s boarding groups, A, B and C, are based on check-in time, loyalty participation in its Rapid Rewards program or through purchase of products such as early bird or upgraded boarding, he said. Check-in begins 24 hours prior to a flight’s departure.
Up to two adults traveling with children 6 years old or younger may board during family boarding, between the A and B boarding groups, Perry said.
He also encourages families to speak with a customer service agent at the gate and with flight attendants after boarding for additional accommodations.
Dallas-based Southwest Airlines famously operates on an open seating basis, allowing passengers to pick their seats when boarding the aircraft.
“Open seating provides a great opportunity for families or groups traveling together to sit together on the aircraft,” Southwest spokesman Chris Perry said. “Customers traveling on the same reservation receive boarding positions adjacent to one another upon check-in.”
The airline’s boarding groups, A, B and C, are based on check-in time, loyalty participation in its Rapid Rewards program or through purchase of products such as early bird or upgraded boarding, he said. Check-in begins 24 hours prior to a flight’s departure.
Up to two adults traveling with children 6 years old or younger may board during family boarding, between the A and B boarding groups, Perry said.
He also encourages families to speak with a customer service agent at the gate and with flight attendants after boarding for additional accommodations.
United Airlines suggests passengers book and select seat assignments early to have the best chance to have a child under 15 years of age seated with an accompanying adult. Additional charges may apply.
“If it’s important for your family to sit together, you may want to consider purchasing advance seat assignments, if available, or selecting a different fare option,” according to the website.
If seats are not selected in advance, the airline will try to find adjoining seats for those on the same reservation prior to departure. But the airline warned that families may be split up.
If passengers would like to sit with a child booked on a separate reservation, they can call the United Customer Contact Center at 1-800-864-8331.
“While we strive to seat your family together, seat selections are not guaranteed and may be changed, including in the event of an aircraft substitution,” according to the website.
United Airlines suggests passengers book and select seat assignments early to have the best chance to have a child under 15 years of age seated with an accompanying adult. Additional charges may apply.
“If it’s important for your family to sit together, you may want to consider purchasing advance seat assignments, if available, or selecting a different fare option,” according to the website.
If seats are not selected in advance, the airline will try to find adjoining seats for those on the same reservation prior to departure. But the airline warned that families may be split up.
If passengers would like to sit with a child booked on a separate reservation, they can call the United Customer Contact Center at 1-800-864-8331.
“While we strive to seat your family together, seat selections are not guaranteed and may be changed, including in the event of an aircraft substitution,” according to the website.
Delta Air Lines directs people to contact Delta Reservations if traveling with children older than 2 and if families want seats together.
Additionally, in 2019, Delta launched a dynamic seat map, which “helps ensure more families are able to sit together based on data from certain routes and flight schedules.”
“Delta works closely with our Advisory Board on Disability that provides guidance for ongoing education and investments to ensure an accessible travel experience,” a Delta representative said in a statement. “We have also created innovative seat map displays that provide seating choices in all cabins for customers traveling alone, or with others — including children.”
Delta Air Lines directs people to contact Delta Reservations if traveling with children older than 2 and if families want seats together.
Additionally, in 2019, Delta launched a dynamic seat map, which “helps ensure more families are able to sit together based on data from certain routes and flight schedules.”
“Delta works closely with our Advisory Board on Disability that provides guidance for ongoing education and investments to ensure an accessible travel experience,” a Delta representative said in a statement. “We have also created innovative seat map displays that provide seating choices in all cabins for customers traveling alone, or with others — including children.”
Small planes are easier to electrify, but larger ones aren’t far behind. Chalabala/istock via Getty Images
Air Canada and United Airlines have ordered 30-seat regional hybrid-electric planes from Heart Aerospace that can go about 125 miles (200 km) fully electric and 250 miles (400 km) as hybrids. With a 25-passenger configuration, the company says the hybrid distance doubles. Heart Aerospace
Ampaire reported that its hybrid electric EEL had fuel savings up to 40% compared with a standard version of the similar Cessna Skymaster. Ampaire