From the article: conventional fuel for a 100 mile flight costs $400, while electric energy would cost $12.
This seems like such a tremendous difference that the market would be in an arms race to make it a reality. Especially considering electric motors have fewer moving parts and so require less maintenance. Oh and it would be so quiet.
> Even assuming huge advances in battery technology, with batteries that are 30 times more efficient and "energy-dense" than they are today, it would only be possible to fly an A320 airliner for a fifth of its range with just half of its payload, says Airbus's chief technology officer Grazia Vittadini.
> "Unless there is some radical, yet-to-be invented paradigm shift in energy storage, we are going to rely on hydrocarbon fuels for the foreseeable future," says Paul Eremenko, United Technologies chief technology officer.
> The big problem with this is that 80% of the aviation industry's emissions come from passenger flights longer than 1,500km - a distance no electric airliner could yet fly.
The market would be in an arms race if energy density was sufficient for long haul flights. Electric flight is awesome but until energy storage/density gets closer to hydrocarbons, conventional planes aren't going anywhere for the majority of travelers and cargo.
A320 family range varies from 5500km to 8700km, so "a fifth of it's range" is around 1500km, which is 80% of the industry emissions.
I'm not sure of that quote either -- a lithium ion battery is currently about 1MJ/kg and 1MJ/litre. Jet fuel is 43MJ/kg and 35MJ per litre (values from from wikipedia)
So a battery that's 30 times more energy dense will be in the region of jet fuel, and thus would presumably be able to fly an A320 for its current range with its current payload.
To do current payloads at 1/4 range (what you'd need for those flights under 1500km) at A320 payloads, you'd need batteries to presumably be in the 5-10 times as dense level, and that's the range that lithium-air batteries would sit.
Don't forget that the fact that the fuel is burnt up as you travel is a big factor in the range of an aircraft. The weight of batteries does not go down during the flight.
How much does this affect an aircraft range? I assume the mechanism is that lighter aircraft needs less lift, and less lift means less drag, less drag - less power on the engines - less fuel consumption - more range.
I somehow always thought that more weight of an aircraft lessened its range almost only because it needs much more power to take off and gain a cruising altitude.
The 80% figure are flights longer than 1500 km. 1500 and less are the 20%.
So even if all those flights were switched to magic zero emission electricity, the aggregate improvement over the whole industry would barely beat the relative improvement between a 737 NG and a MAX. (yes, this is an apples to orchards comparison)
That's not strictly correct. There are MAX's flying every day. At this moment, there are two in the sky.
Grounded from carrying passengers, but not grounded entirely from flying, and certainly emitting in any case. The two on the map now are out of Boeing Field.
> Jet fuel is 43MJ/kg and 35MJ per litre (values from from wikipedia)
Jet fuel is really about 12-15 MJ/kg when you take thermodynamic losses into account. So you;d need a battery 10 times as dense. Which likely isn't happening any time soon, but still.
I think with full electric aircraft it's not a case of 'won't work' but how big of a niche they can carve out. Probably the sector they'd compete in are general aviation and puddle jumpers.
This is why I'm so excited for lithium-air batteries. Theoretically they'd carry ~40.1 MJ/kg, which is very competitive with gasoline's ~46.8 MJ/kg. Factoring in the higher efficiency of electric drives (95% vs. 35% for say a regular ICE car), you'd be getting effectively over double the energy per pound in terms of moving you around.
At nearly double energy efficiency, nobody will care much about the weight of the batteries. Some airplane design changes due to no longer being able to take off heavier than they are allowed to land (this is common on long hauls) but the design changes also likely change due to better placement of thrust and its weight (engines go almost anywhere the designer wants), and better control over location of the weight (batteries aren't liquid and don't slosh around, and a sloshing liquid also has negative aerodynamic effects.)
It's a game changer for airlines such as Harbour Air in British Columbia and Mokulele Airlines in Hawaii. These are small regional airlines which operate from the water or from small airports with flight times usually less than an hour, and most of their operational expenditures are in fuel costs. Typically for these airlines you show up 15 minutes before the flight and there is no security screening, so it's very hassle free.
Think of what it could do in other areas as well too though. Imagine a flight from the SF waterfront to Tahoe via seaplane in 45 minutes (instead of 4+ hours) with no TSA screening, or potentially even SF to LA in 90 minutes.
Unfortunately the battery weight is also currently prohibitive for small companies such as Harbour Air and Mokulele.
Several weeks before the Harbour Air / MagniX announcement I ran through an exercise to determine the range/payload of an electric Cessna 208 (Caravan) for a typical flight profile here in the bay area: the daily FedEx flight from Oakland International to some nearby city, such as Petaluma. This involves a 5min climb from take-off to 2000ft, some period of cruise flight (ultimately determined by range), and a 7min decent to land.
This calculation assumes that the C208 swaps the swaps its turbine (PT6A-114A) for the Magni500, saving 85lbs. It also accounts for the substantial increase in conversion efficiency between the MagniX and PT6 (roughly 0.94 from 0.32). Not accounted for are any differences in aircraft systems (de-ice, prop pitch, electric instruments, plumbing, etc).
The results are not surprising given what others have noted about the enormous difference between the specific energy densities of Jet A and LIB. At the specific energy density of today's production batteries, 250 w-hr/kg, the electric C208 could carry one 175lb pilot approximately 100mi in 39min. Due to FAA VFR regulations, this would in reality limit the flight to 9min (FAA requires daytime reserve of 30min), with the subsequent loss in range.
Let's consider the putative solid state battery at 500 w-hr/kg. Now a 60min flight time (really 30min plus 30min reserve) will allow 1080lb payload. Fantastic! That's a pilot plus 4-5 passengers. The catch, of course, is that the timeline for road worthy SS batteries is 5-10 years. How long for before an air worthy battery is available?
With this information parsing the press statements is a little easier. Will the Harbour Air / MagniX Beaver carry 6 passengers over a 30min flight? No. It may demonstrate electric flight of a utility category air frame with the pilot as the "soul" payload. After that both companies will likely be in the same position as the rest of us -- waiting on better battery technology.
> The XF-84H was almost certainly the loudest aircraft ever built, earning the nickname "Thunderscreech" as well as the "Mighty Ear Banger". On the ground "run ups", the prototypes could reportedly be heard 25 miles (40 km) away. Unlike standard propellers that turn at subsonic speeds, the outer 24–30 inches (61–76 cm) of the blades on the XF-84H's propeller traveled faster than the speed of sound even at idle thrust, producing a continuous visible sonic boom that radiated laterally from the propellers for hundreds of yards. The shock wave was actually powerful enough to knock a man down.
It would make about as much noise as it makes now. Nearly all the noise of a commercial aircraft is caused by the air being pushed to propel it, not by the engine internals.
(You can reduce noise and increase efficiency by pushing more air at a smaller speed. You do that by having more engines or larger ones. I would expect electrical planes to have more engines, but that's a small secondary effect.)
I think the big question would be how much the base equipment costs and the significant power density limitations. It takes time to get established against a very mature technology and batteries are a big limiting factor:
“Even assuming huge advances in battery technology, with batteries that are 30 times more efficient and "energy-dense" than they are today, it would only be possible to fly an A320 airliner for a fifth of its range with just half of its payload, says Airbus's chief technology officer Grazia Vittadini.”
I'm sure everyone would like to switch for environmental reasons but that sounds like a really big gap to fill.
Own a single engine piston that's fuel efficient. In my plane 100 miles would be about $40 in fuel conservatively. Amortized maintenance costs are much higher than $40, but still not even close to $400. The article mentions a Caravan which is a bigger single engine turbine, not piston.
Fewer moving parts doesn't mean reliable and not subject to catastrophic unforeseen failures. If it hasn't been out for five years you're a test pilot.
REDMOND, WA and VANCOUVER, B.C. – March 26, 2019 – magniX, the company powering the electric aviation revolution, and Harbour Air, North America’s largest seaplane airline, today announced a partnership to transform Harbour Air seaplanes into an all-electric commercial fleet powered by the magni500, a 750 horsepower (HP) all-electric motor.https://news.ycombinator.com/item?id=19539796
Um, that’s comparing a jet engine to an electric prop. Apples and walnuts - the two propulsion methods couldn’t be much more dissimilar. A more equivalent prop plane (with similar capacity) would be well under $100 for fuel costs, potentially even under the $50 range.
This seems like such a tremendous difference that the market would be in an arms race to make it a reality. Especially considering electric motors have fewer moving parts and so require less maintenance. Oh and it would be so quiet.