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First all-electric seaplane takes flight in B.C.

cbc.ca

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Re: First all-electric seaplane takes flight in B.C.

#51

I found this article by the CBC more informative then the one linked: https://www.cbc.ca/news/canada/british-columbia/electric-sea... > "It's a prototype for sure," said McDougall, "but in every way it's a high-tech piece of equipment, which is kind of ironic considering the airframe that it's attached to is actually one year younger than me — 62 years old." > McDougall's flight is the first exercise in what is expec…

Ok, we'll change to that from https://www.bbc.com/news/business-50738983. Thanks!

Re: First all-electric seaplane takes flight in B.C.

#52
post #2

The title is a little misleading: This is not a commercial flight, currently the plane in question is licensed by the FAA as "experimental" specifically excluding commercial flights. Still cool! I think electric might have a great future in short-hop flights.

The title is now different above because we changed the URL from https://www.bbc.com/news/business-50738983.

Re: First all-electric seaplane takes flight in B.C.

#53

You can do small aircraft like this, no problem. The trouble is you can't scale it up, due to how quickly the power and energy demands go up. This thing is 560 kW and gets a range of 86 nmi; an A320 is around 40 000 kW and has a range of 3 500 nmi, while an A380 is around 80 000 kW and has a range of 8 500 nmi. Going from this DHC-2 to the A380 requires an increase in energy storage by a factor of around 14 000x, whi…

Fuel cells are a possibility. There is some pretty high power densities (2.5kw/kg for SOFCs, 10kw/kg for less efficient PEMs). Electric motors are now reaching 15kw/kg. For comparison, a GE90 is about 10kw/kg, and older turbofans down to 2kw/kg. Running on liquid hydrogen presents some problems that are definitely solvable, but SOFCs can run on pretty much any hydrocarbon fuels at extremely high efficiencies (50-60%, 80% with combined cycles, compared to the ~45% that jet engines get).

I actually think the future may be a lot more simple than we're making it out to be. With some slight modifications to design, we could run existing turbofans on liquid hydrogen fuel. The biggest objection that most people have is the storage of hydrogen...but liquid hydrogen doesn't actually need to be stored in cryo tanks as long as the fuel is being used at faster rates than it evaporates. That's not a problem with jet engine consumption rates...low tech insulation may be sufficient.

Re: First all-electric seaplane takes flight in B.C.

#54
post #3

Off topic and stupid, but could an electric plane be outfitted with lightning rods and/or lightning rockets to attract lightning strikes in order to charge the batteries?

The idea that a lightning bolt could be used as a power up source has been thoroughly debunked by myself and others in this thread already, but I thought I’d take another angle in response, just using electricity in general.

A single GE90 aircraft jet engine used in the 777 is up to 111,000 horsepower[0]. So for the Boeing 777, that’s ~220,000HP. Converting horsepower to megawatts, that’s 164MW of power during takeoff (and approximately half that during flight). There’s approximately 500-1000 B777s (very rough, but educated guess) in the air at any given moment during the day. That’s 82.5 gigawatts of power just for the 777 flights alone, not counting all the other commercial aircraft in use.

So how much is 82.5GW?

> The Palo Verde nuclear power plant in Arizona is the largest nuclear power plant in the United states with three reactors and a total electricity generating capacity1 of about 3,937 MW.

So 40+ of the largest nuclear power plants in the US?

> average wind turbines produce 1.5MW of power at 100% efficiency

So 55,000 wind turbines at minimum? Better hope it’s windy!

Flipping it another way:

> an average LCD TV uses 200W of power

So in other words, turn off 400M TVs around the globe to offset the power needs of up to just 1,000 planes.

Now finally...

ignoring the electricity generation needs, let’s talk about just battery storage on the plane itself. A typical 18650 (the battery that is commonly used to make large cells, for example in your electric cars) is something like 9W of power. So you’d need something like almost 20,000,000 batteries just for a short flight. Each 18650 weighs about 45g (not including wiring harnesses and safety gear). That’s 200,000 pounds of batteries. The batteries alone for a short flight is multiples of the weight needed in fuel for an international flight.

[0] https://www.bangaloreaviation.com/2009/10/worlds-largest-air...

Re: First all-electric seaplane takes flight in B.C.

#55

Carbon neutral biofuel or fuel made via excess solar/wind should probably be the goal. Fuel cells might be viable too and the regulated commercial nature of planes probably means that hydrogen's storage and pumping headaches wouldn't suffer the consumer problems. But biofuels are probably the way to go for now. There are probably hybrid airship designs with solar panels that could do lower cost shipping. All that ext…

https://www.varialift.com/page/specification-arh-50

200mph at altitude... well, with the jetstream it seems.

Also, could electromag catapults help with takeoff?

Re: First all-electric seaplane takes flight in B.C.

#56

You can do small aircraft like this, no problem. The trouble is you can't scale it up, due to how quickly the power and energy demands go up. This thing is 560 kW and gets a range of 86 nmi; an A320 is around 40 000 kW and has a range of 3 500 nmi, while an A380 is around 80 000 kW and has a range of 8 500 nmi. Going from this DHC-2 to the A380 requires an increase in energy storage by a factor of around 14 000x, whi…

How would planes would look like if fuel prices increased a few fold? I would assume probably less jets and more turbine aircraft, at least on short trips. Straight wings and slower speeds. Boeing and Airbus might lose some market share. Boeing never had a turboprop, Airbus owns 50% of ATR.

> less jets and more turbine aircraft

Assuming you mean turbofan vs. turboprop here, since both of these are turbine-driven.

In either case, my understanding is that turboprops don't present a substantial gain in efficiency, as turbofans allow for higher and faster cruising altitude, which reduces drag on the airframe.

Re: First all-electric seaplane takes flight in B.C.

#57

You can do small aircraft like this, no problem. The trouble is you can't scale it up, due to how quickly the power and energy demands go up. This thing is 560 kW and gets a range of 86 nmi; an A320 is around 40 000 kW and has a range of 3 500 nmi, while an A380 is around 80 000 kW and has a range of 8 500 nmi. Going from this DHC-2 to the A380 requires an increase in energy storage by a factor of around 14 000x, whi…

> This thing is 560 kW and gets a range of 86 nmi Not even that. I believe an 86 nmi range is what they are hoping to achieve by 2025. Current range is a fraction of that. The technology demonstrator has a theoretical flight time of 15 minutes and no ability to carry passengers because all the room/weight is taken up by batteries.

It seems to me that they have two somewhat separate engineering challenges. The electric motor and throttle control system, all the drive train stuff forward of the instrument panel in a Beaver. Plus however they retrofitted the cockpit engine control. Which might be quite a bit lighter than a pt6 turbine retrofit to turn an old Beaver into a turbo Beaver.

And then the other much harder problem which is achieving sufficient Wh per kg energy density in batteries, and Wh per litre of volume. For which they are dependent on global factors for r&d of batteries and improvement in density.

Re: First all-electric seaplane takes flight in B.C.

#58

You can do small aircraft like this, no problem. The trouble is you can't scale it up, due to how quickly the power and energy demands go up. This thing is 560 kW and gets a range of 86 nmi; an A320 is around 40 000 kW and has a range of 3 500 nmi, while an A380 is around 80 000 kW and has a range of 8 500 nmi. Going from this DHC-2 to the A380 requires an increase in energy storage by a factor of around 14 000x, whi…

That's all undoubtedly true, but fortunately, most flights don't require the capabilities of an A380, and in fact, demand for that specific set of capabilities is apparently low enough to stop building them altogether. Even for A320 flights, most are not 3500 miles, even if the aircraft is capable of it. If we could make progress targeting just short hops targeted by DASH-8s or CRJs or whatever, we could still make s…

All electric with this century's technology might work for 8-16 passenger short-haul aircraft, if that market can be created (think, many flights from various regional airports between the SF Bay Area and LA area). Nothing bigger is going to fly without a massive breakthrough in battery energy density.

Re: First all-electric seaplane takes flight in B.C.

#59

Carbon neutral biofuel or fuel made via excess solar/wind should probably be the goal. Fuel cells might be viable too and the regulated commercial nature of planes probably means that hydrogen's storage and pumping headaches wouldn't suffer the consumer problems. But biofuels are probably the way to go for now. There are probably hybrid airship designs with solar panels that could do lower cost shipping. All that ext…

Oh, and another thing, while long haul flights won't be impacted, self-driving cars and trucks will obliterate overland short hop flights, and for trucking probably medium range (1000miles) as well. 12 hours of driving 7pm to 7am overnight at 50mph average is 600 miles, and at 70mph with some convergent infrastructure would be 840 miles.

Re: First all-electric seaplane takes flight in B.C.

#60

You can do small aircraft like this, no problem. The trouble is you can't scale it up, due to how quickly the power and energy demands go up. This thing is 560 kW and gets a range of 86 nmi; an A320 is around 40 000 kW and has a range of 3 500 nmi, while an A380 is around 80 000 kW and has a range of 8 500 nmi. Going from this DHC-2 to the A380 requires an increase in energy storage by a factor of around 14 000x, whi…

Fuel cells are a possibility. There is some pretty high power densities (2.5kw/kg for SOFCs, 10kw/kg for less efficient PEMs). Electric motors are now reaching 15kw/kg. For comparison, a GE90 is about 10kw/kg, and older turbofans down to 2kw/kg. Running on liquid hydrogen presents some problems that are definitely solvable, but SOFCs can run on pretty much any hydrocarbon fuels at extremely high efficiencies (50-60%,…

There reportedly is an additional threat to the climate coming from inversion traces (modifies enough of Earth albedo?), so if we're delivering water to high altitudes, it's still not good.

Electrical motors would solve this; if we'd be able to avoid dispersing water from fuel cells up high, that could work.

LH2 has storage - and safety - issues still not solved. Toyota Mirai approaches it from a different angle, with some other shortcomings.

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