Some interesting news from Vancouver’s Harbor Air and their plans to convert all of their seaplanes to 750 HP electric motors and lithium batteries. Pretty limited predicted range of only about 100 miles but they specialize in short duration trips so that 100 miles is actually quite suitable even with the safety margin included. The article also mentions about how 75% of commercial flights are 1000 miles or less so with advancements in battery technology, they see huge potential. Must admit that whenever I hear about electrifying airplanes, I have some serious doubts about the practicality of it versus conventional power. Seaplanes that only hold 6 passengers and are short flights that doesn’t require much altitude gain is one thing but how feasible is an electric powered plane for any flight that places them at an altitude were colder weather will be experienced? I don’t know how much of an impact on a conventional plane cold or stormy weather will have on it’s range but I’m sure it’s much less then what would be experienced with an electric powered plane. At any rate, it’s a step in the right direction and it would be interesting to experience a flight in one. Would seem pretty weird with the much reduced noise levels vs a turboprop engine. Be interesting to hear from any aviation or electrical engineering experts about this.
Where’s the info about the range of these planes? Not that I doubt your word, but the Seattle-Vancouver trip is longer than 100 miles. Are these guys going to have to stop in Chehalis or Olympia to recharge?
At any rate, the X-57 should improve the range of electric planes.
Odd. I thought that info was in the link but it obviously isn’t. Here’s another link to the BNN interview with the CEO of Harbor Air and he says 1/2 hour flights with a 1/2 hour reserve. Not sure how I got the 100 mile range in my head? I take it that the electrification roll out would be over a number of years and by the time it was completed the range would have increased to be able to include Seattle.
What’s today’s date?
Article is from the 26th.
It seems like recharge time would be a big problem for commercial airlines.
I know they try to keep their planes flying frequently – often taking off on a new flight within an hour or two of the previous landing. (As they say ‘the airplane only makes money when it’s flying’.) While small, short-trip planes may be able to accept a few hours recharge time between flights. the multi-million airliners need to be in the air more often than that.
It is an established fact that, in some places anyway, we use windmills to generate electric power. My question is, why can’t planes (at least partially) recharge while in the air by having props that spin and produce electricity? The plane’s movement through the air is equivalent to a sustained wind. Explain, please.
Checking the Harbour Air schedule, it looks like I made a mistake. Seeing the name Vancouver, I assumed it was the local Vancouver, that is the one in Washington across the Columbia from Portland. Instead, it’s the other one in BC. Still it’s more than 100 miles for that Van-Sea route. Also at least one of the other routes is more than 100 miles (Van-Tofino).
For the same reason this doesn’t work.
Yes, they could recharge when descending. I’m not sure if the engines would have to be specially modified to do it, but there’s no reason at all this couldn’t be done. The plane would get back some, but not all, of the energy that it took to ascend that high. It would reduce the amount of recharging needed to be done, but wouldn’t eliminate it.
The basic problem I see - current air regs require 45 minutes reserve for any planned flight. That means for a 1-hour flight the aircraft would need 1h 45m flight capability. If it’s a stretch to fit the necessary weight of batteries into thee aircraft to start, then almost doubling the power requirements is a bit of a handicap. Then, consider that a typical fueled aircraft can go several hours for the same take-off weight. Battery tech has a ways to go. I suppose that flying a float plane along the coast is likely the safest application of battery flying, since the opportunities to “land” are better. I think the main selling point is that an electric motor can weigh significantly less than equivalent HP gasoline engine, so the lower engine weight plus no fuel weight can compensate for battery weight. Plus an electric motor is far less complex. I wonder if hydrogen fuel cells making electricity would be a passable compromise?
A windmill works by creating resistance against the wind. When the windmill is anchored in cement, it doesn’t matter. When the gaol is to move the windmill through the air at 100-plus mph, creating resistance to run a generator is a zero-sum game (actually, worse). Yes you can generate power while descending, but presumably you are descending to land where (a) you don’t need a lot of power any more and (b) you better have sufficient reserve power anyway. All it would do is shorten charging by a few minutes, maybe.
Yes but I’m assuming electrification wouldn’t be done to all their aircraft at once so the more distant routes would be still taken care of by conventional planes until battery technology improved enough to go with electric planes. Assuming this all pans out of course.
Yes, excellent point. I wonder how feasible it would be to have swap out battery packs instead of being totally reliant on recharging? Fair bit of weight involved but surely they could come up with something that a forklift could be used with.
Electric power is unlikely to be much use for passenger travel but would be great for drones operating for days or weeks. Any flying/floating thing that requires a lot of energy spread over a long duration but little energy at any one time.
It would increase drag by at least as much energy as you’re getting. If you picture the same thing being tried on a car or a submarine, you can see that you wouldn’t come out ahead.
With what the CEO said in the BNN interview, I believe the 1/2 hour reserve mentioned would be for proof of concept flights with no passengers involved. From the way he was talking, it sounded like he was sure the battery technology would improve rapidly enough that by the time passenger flights were green lit, the 45 minute reserve requirement would be met.
The planes are conversions of ICE planes, so I woudn’t expect them to be modified for quick swapping of batteries. Not saying they couldn’t be done that way, but it’s more work. Also there’s an increased chance of things going wrong, that is, more so than just simply plugging in the recharger. And using high voltage rechargers with more than one plug, they could probably get the recharging down to less than an hour.
Another advantage, unlike fueled aircraft, the battery weight does not really change as the batteries are used - so the packs can be distributed all along the plane (i.e. as floorboard, like Tesla does with their cars) as long ass the balance is observed. Fuel is necessarily in tanks centered around the wings (center of gravity) because (a) in the wings is a convenient place, and (b) the balance doesn’t change significantly as the fuel is used.
So two things.
- Cold weather. This isn’t a problem like it sounds. Cold weather makes cold lithium batteries produce less power. (the total energy stored is the same of course)
The fix for this problem is to have the plane connected to an external power source while at the gate/on the taxiway. The external power source, which could be another battery pack or a tow cart with an engine and a generator, would supply power to the plane, allowing it to keep it’s batteries at full charge and to run heaters so the batteries are warm.
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Why do this since batteries suck? The reasons to do this are 2 main reasons :
a. Electric torque is extremely high and extremely fast responding. This allows for VTOL aircraft without needing complex prop feathering mechanisms. These VTOL aircraft are often proposed as hybrids, where batteries are used for takeoff power but cruise power comes from a turboprop engine turning a propeller. As I understand it, this type of VTOL just isn't practical with engine driven props. (for the VTOL phase of flight, obviously in the cruise phase the aircraft would fly like a conventional aircraft) b. For short distance flights, it *might* reduce operating costs. Might. The problem with the batteries is yes, you save on jet fuel. But you burn some of the battery pack's life with every flight. After 500-1000 total flights, you need to replace the battery pack. This is a substantial expense - aircraft rated lithium battery packs won't be very cheap per kWh and they will need to also be pretty large.
Example numbers : say it’s a 4 passenger commuter VTOL. It has a 100 kWh battery pack. It needs replacement ever 750 flights. Say the cost per kWh for an aircraft-grade battery is $250. So that’s a $25,000 expense every 750 flights, or $8 added to every ticket just to pay for the battery. Except for a commute VTOL, it probably makes about half it’s flights with no passengers onboard, so possibly more like $12 just for battery replacement. Oh, and on many flights there might not be a full passenger load.
This is a substantial cost and it’s probably more than the cost of the fuel the aircraft would burn.
OK, some quick back of the napkin calculations based off the DHC-2 Beavers that Harbour Air currently operates. ICE config: P&W Wasp Jr, 640 Lbs , 450 hp, carries 138 gal fuel (884.5 lbs full up based on 6.41 lbs/gal), and 6 gal of oil (100 wt .886 kg/l, so about 44 lbs.) So total ICE bits rough out to 1570 lbs.
Electro-Beaver: Magnix Magni500 265 lbs, 751 shp, 93.8% efficiency. That leaves 1300 lbs for batteries, Assuming you use something similar to a 100 KWH Tesla pack which weighs roughly 1200 lbs, that would give you 2 hrs of flying time (remembering that you only have peak draw at take off), and a range of about 300 miles at 150 mph. There are a ton of variables here but the biggest is how much battery can you stuff in and still keep the 2000 lb usable weight.
Another factor to consider is the cost of upkeep on WW2 era radial engines, which will be offset considerably in the near zero maintenance (comparably) of the electric motor so I’m not sure the amortized battery cost will be a deal killer.
A (semi) serious question: Do you install speakers or some other noise-generating equipment so ground crew know the props are spinning?
The (much less) serious question: How are the tower crew going to stand outside and listen for the returning planes that lost one motor? I see it all the time in WWII movies.