Posted on 09/28/2017 6:23:11 AM PDT by Red Badger
The auto industry is going electric. Is aviation next?
Major European carrier EasyJet announced Wednesday that it is teaming up with U.S. startup Wright Electric to build an all-electric airliner.
The aircraft they have in mind would handle short routes of 335 miles or less -- think New York to Boston or London to Paris.
EasyJet, a budget airline that specializes in shorter flights, said the new aircraft would cover 20% of its passenger journeys.
The airline said it has been working closely with Wright Electric this year and it hopes to have an electric commercial aircraft flying in the next decade.
"We can envisage a future without jet fuel and we are excited to be part of it. It is now more a matter of when not if a short haul electric plane will fly," said EasyJet CEO Carolyn McCall.
Wright Electric was founded in 2016 by a team of battery chemists, aerospace engineers and electric vehicle experts from NASA, Boeing (BA) and Cessna.
It received funding from Harvard University and startup incubator Y Combinator, which helped fund Dropbox, Reddit and Airbnb. EasyJet did not reveal the financial terms of its partnership with the startup.
Jeffrey Engler, the chief executive of Wright Electric, said that working with EasyJet is "a powerful validation of our technology approach."
EasyJet said the startup has already demonstrated its first two-seater plane, showing it can make the technology work on a smaller scale.
(Excerpt) Read more at money.cnn.com ...
And if the batteries peter out during flight, then what?
Each passenger will have one of these under the seat:
Imagine what will happen if they have to get into a holding pattern.
Let’s just say a typical small airliner carries 40,000 pounds of fuel. That’s 18143695 grams. A 18650 Li-Ion cell like those used in the Tesla S weighs 45 grams, to that’s 403,193 cells and a single cell contains 10 watt-hours of energy. So that’s a tad over 4 million watt-hours of energy available for a flight.
A 747 uses about that much energy (90MW for 5 minutes = 4.5MWH) just to get off the ground. But that’s with over 10 times as much fuel weight and an airframe that is 4 times heavier. It is reasonable to expect that a small airliner using modern composite materials and design could be made that would require a small fraction of the 4.5 MWH it takes to lift a 747 off the ground. Let’s say it still takes 1 million watt-hours (which seems quite high) - that leaves 3 MWH of energy for the cruise portion of the flight and landing (where relatively little energy is required).
Li-Ion battery technology improves literally on a daily basis, with an average reduction in weight of 8% per year for the past 5 years for the same energy density. An electric airliner will be feasible once battery technology and airframe design evolve sufficiently. It is a matter of when, not if.
You'd definitely have to skimp on the air conditioner to make this work, and spend a whole lot of money on solar panels.
A 42-ft motorhome is usually 101" (8.42ft) wide, giving a roof area of 353.5 sq ft, or 32.84 sq meters. Let's stipulate that the roof extends up on one side by a 15º angle, which increases the roof area to 32.84 / cos(15º) = 34 square meters.
In my part of Alabama, we get 3 - 4 kWH per square meter per day in June. Let's say it's 4. The motorhome solar panel has 4 x 34 = 136 kwH per day of sun falling on it.
The highest efficiency solar panels I've found on the Internet, from Panasonic and Sunpower, claim 22.5% efficiency. Let's say the marketing hype is true. Then you can get 136 * 0.225 = 30.6 kWh per DAY. That doesn't include battery charging and discharge losses, which probably will take you down to about 80% of that, or about 24.5 kwH per day.
Ramsond says their 15000 BTU RV air conditioner requires 3.5 kW just to start up (say it takes 1 min to start up, so we've used 58 wH), and 1.5 kH to run. You can run the air conditioner, and only the air conditioner, for about 16 hours off the stored solar power.
It's going to be hot for the other 8 hours while you charge the batteries again.
This doesn't look very practical, and I've just calculated the A/C load.
Modern RV appliances and appliances optimized for solar battery banks have a “soft start” in order to minimize the startup draw, so your numbers are off in that regard.
Go to the link to Precision RV that I provided and look at the several large installations shown that power the entire house functions of the RV. These retrofits are not cheap and they would not be selling if they do not function as advertised, RV’ers are not generally pie-in-the-sky leftie dreamers, they’re a practical lot.
I’ve been following this as it’s been developing for over two years now. Two years ago, yes, you’d have been correct. Running the A/C on solar-powered battery bank would have worked for at best a few hours, not overnight. Not so now.
You are describing a ducted fan, and not a jet.
Yes, no problem, the model RC folks are already doing it. Just like Tesla wires together lots of cell phone batteries, EasyJet simply needs to use a bajillion of these 3 inch diameter units. Only $39 each, but I'm sure they will qualify for a volume discount. :^)
Most Subarus have 4 or 6 cylinder boxer engines. You just described their sales and marketing department.
We borrowed a vehicle from a doctor friend for a short time a few years back. It was during the winter, and the heater didn't work well. I discovered that someone had removed the thermostat. He thought you only needed that during the summer. Needless to say, I remedied the problem and the ignorance about the problem.
How many salmon will have to die in hydro turbines to power this?
How many birds and other wildlife will have to die in solar and wind farms to power this?
Oh, the humanity!
Not my airliner. If I need to go anywhere, I’ll drive. Don’t need to be groped or packed in like a sardine. No, I have no desire to travel outside the US anymore.
I took the numbers off the Ramsond RV air conditioner website, which I linked. So what's wrong about them? Only thing I guessed about was the length of time for startup. I'll even stipulate NO startup time. You still only get a little more than 16 hours.
Again, I used THEIR numbers. My only "SWAG" was the battery conversion efficiency of 80%, which I supplied from my expertise of 30 years as an electrical engineer designing switching power supplies, big and small.
Please tell me what's wrong with this analysis. I want a PV backup at my country home (not for A/C though), so I need to do this right.
I can’t wait to see them dump batteries in an emergency. I’m an EE. This is the stupidest idea ever.
Not saying it can’t be done, but nothing compares on an energy/lbs basis like petroleum-based fuels.
I’ll wait for Uber-Air, thanks.
Batteries tend to do very poorly at cold temperatures...and making an extension cord that goes from JFK to Dubai might be difficult.
In addition to “soft start” appliances, the inverter(s) play a major role as does choice of type of electrical appliance or A/C unit. Here’s an ideal Danfoss compressor refrigerator for such applications (there are larger models):
http://www.backwoodssolar.com/novakool-dc-refrigerator-model-r5810
In addition, mobile Danhard A/C units with variable speed compressors are ideal for such applications. The startup power draw is minimized as is the running power draw.
The same is true for True Induction cooktops, microwave/convection ovens, just about anything you’d put into an RV. The domestic, US RV industry has been rather slow to adapt to this, but it’s been innovated largely by the Australians who have taken the matter even further along, with ducted mini-split RV air conditioning systems, Danfoss compressor refrigerators with “eutectic plate” in order to utilize power from the engine alternator to get a jump on cooling the refrigerator while being driven. Large secondary alternators are also being used to maintain or increase charge to the lithium ion battery bank. Maybe it sounds like “cheating” to start with a fully charged battery bank, maybe that’s why your numbers indicate that the system cannot work. All I know is, it does work, I’ve been pretty thoroughly researching the matter for years as I mentioned.
Here’s a brand-new offering from Winnebago called the “Revel” however, that does demonstrate that the domestic RV industry is beginning to wake up to the new reality, a very handsome 4x4 Sprinter conversion with many of the appliances I discussed, with the exception of the A/C unit but they do use one of the most efficient rooftop units available (cost considerations I’m sure, since the very similar Sportmobile uses a proper Danhard unit, but they’re more expensive):
https://winnebagoind.com/products/class-b/2018/revel/overview
Exactly right. Anyone who says different doesn't know the science.
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