Resistive electric heating is only about 40 to 50% efficient. Here’s where the waste heat goes.
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Why not just store natural gas instead of compressed air? Can plants use a lot of gas for various processes. So during the bad old days in the 70s when supplies were not consistent, the plant installed two huge gas tanks to be able to operate regardless. If this keeps up we may see the same thing in back yards. Freeze me once shame on you. Freeze me twice shame on me.
How would solar panels generate natural gas? Seems the goal would be to store energy collected during the day for night use. A natural gas pipeline from Russia to your house might be an alternative.
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Yeah that’s the fallacy of the whole argument. Plenty of clean.gas easily stored. We have plenty ourselves so no need for help from Russia. But common sense is a rare commodity in the halls of government.
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I would hardly describe natural gas as “easy to store”, we mostly just draw it from gas wells as we need it. It can be liquified by chilling it to minus 263.2 F, but no amount of pressure will raise its boiling point to room temperature.
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I’d wait til they get the battery fires figured out.
Well, let’s not distract from the original discussion which was simply related to which was more efficient at generating heat for a passenger cabin.
If you want to go that route, solar energy is only 0.00000001% efficient, here’s where the waste heat goes:
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Actually, much of the natural gas we use in cold weather comes out of storage fields, where they pump it from the original gas wells during low demand periods. Up to 1/3 of total gas used on average, more in some areas, less in others.
The original poster mentioned that EVs - stop working in very cold weather. That’s because lithium ion battery chemistry both lose their charge at low temperatures, and at somewhat colder temperatures, are destroyed.
That particular battery chemistry can also lose charge, and be damaged, by hot weather.
I’ve had cell phone batteries destroyed by each of these.
In some climates, cold and/or hot weather will be significant problems.
In any event, at the current stage of technology, hybrid gasoline/electric cars theoretically make more sense for those who occasionally take very long trips. They achieve some of the reliability and efficiency of true EVs, but also achieve the rapid refueling and long range of gasoline powered vehicles.
(I also wonder whether lithium battery chemistries can be redesigned to make the materials recyclable at lower cost than mining them.)
But the biggest issue right now is cost. EVs - as well as hybrids with high enough capacity batteries to function as EVs most of the time, are outrageously expensive. That may be a fixable issue.
There have been proposals to use thermal storage (e.g., molten salts) instead of batteries to compactly store energy for vehicles. I’m not an engineer, but it seems like that could overcome almost all of these problems (extreme weather loss of battery charge and function, rapid refueling, easy recycling) - though it introduces a new one, in that even when the vehicle is off, there is a very hot spot under the vehicle, that could create safety issues if it isn’t managed right. Also, it isn’t clear that practical thermal storage could give an energy density comparable to gasoline.
Maybe home solar energy systems could also be designed that could create the heat for thermal storage - I’m not sure. But you need really high temperatures for practical portable energy density thermal storage for vehicles, even with a molten salt phase change.
I personally love the idea of trying to improve efficiency by moving to much lighter vehicles, like eBikes and eTrikes. But that could never be safe if they share the same roads with heavy vehicles. And there will always be applications for which some heavy vehicles are needed. So I can’t figure out how that could work.
BTW, hydrogen fuel just scares me. I don’t see how it could ever be reasonably safe. Plus, the practical ways of creating it involve electricity, and some rather inefficient stages. Transporting it over long distances would involve insane risks.
BTW, there are moderate cost ways to generate large amounts of electricity - e.g., hydroelectric dams across bays (e.g., see proposals for damming the Bay of Fundy), using tidal power. And maybe someday we will have long distance moderate temperature superconducting power lines that distribute it efficiently. But it would be putting it mildly to say that damming a bay would have severe environmental consequences.
I think we are simply too early in the stage of trying to replace a mature technology with in-place infrastructure support, with new ones that are meant to be environmental more friendly. Right now it may not seem altogether practical. Some time in the future it may be much different.
I am not sure about storing natural gas compressed at room temp but this is done with propane. Instead of compressed air, used compressed fuel gas (LPG or NG) if that can be done so you are storing something that can generate power through a pressure reducing turbine of such while being burned.
Also, there are several pumped storage facilities around the US and the world. These use off-peak power at night or other low-demand times to pump water uphill where it is stored. Then the pumps are reversed and turn into turbines to generate power during high demand periods. Environmentalists don’t like the fact you have to blast the top of a mountain off, dam a valley, or whatever though to construct one of these massive projects.
I really think plug in hybrids are the way to go, at least for me. A pure EV would only work if I was retired and knew I would be making only local trips such as to town and back for groceries.
With regards to LPG or LNG, what environmentalists also don’t like is the fracking needed to produce affordable high quantities, and the deep well storage of the corrosive chemicals involved. It’s a little hard to predict the extent of the future environmental consequences of these things.
Of course, AFAICT, any large scale usable energy system has environmental consequences. E.g., even if there were affordable long-life high efficiency solar cells whose production had negligible environmental impact (not true now), they would change Earth’s albedo.
It might be a good idea to read a Motor Trend article on this topic as well.
Burning hydrocarbon fuels has substantially changed the Earth’s albedo by melting huge amounts of ice and snow. When it’s not white anymore the solar absorptance goes way up.
Two Thirds of all glaciers are on track to disappear in 80 years. Glacier national park only has 26 of 150 glaciers left. Glaciers/snow reflect sunlight. Without glaciers, the more of the suns energy is absorbed.
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Back to cars. My driveway and house are where a glacier used to be, so the problem is? Think in terms of 20,000 year cycles, not 20 years. And from the looks of it today the glacier will soon return.
The old ‘it was hot when the dinosaurs were around’ argument…
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They were killed by an asteroid though not climate so marked as a diversion. Plenty of snow here reflecting back to the sun and I hear the same in California.
Back to hysteria and travel talk. I’ve been to glacier, and Yellowstone and picked the debris up from mt St. Helens. I’d be more concerned about the eruptions from Yellowstone that experts predict will come at any time. It’s a very unsettled part of the country, but we didn’t pay much for it.
The water method seems like it would be pretty efficient, no big energy loss due to heat. Compressing air doesn’t seem like it would as good, b/c some of the energy used to compress the air makes the air get hot. The advantage of compressing air I suppose is it doesn’t take as much space, maybe that’s the motivation. I’m presuming the compressed air is stored in a large naturally occurring cavern somewhere, similar to how natural gas is stored by utility companies.
In 10 minutes of warming up my old 2010 CX-7 my front windshield would barely be cleared of frost, 10 minutes of warming up my 2020 Bolt, the windshield is cleared.
Why do you include the cost of the battery? Do you replace the battery instead of charging it every time?
I remind everyone again to look at things in perspective. You’re something like 3 times as likely to die in a fatal accident in a compact car like that over its 100k mile life that you are to have a fire incident with it.
Did you try to change the battery in very cold temperatures? That kills them.
With all the talk of EV battery fires, maybe the solution is to just have the power source on fire all the time?
The end of my quote should say per mile not per kWh. I include the cost of the battery, because traditionally it has always cost more than the electricity itself. The battery is not replaced every time the car is driven. It is replaced after about 1000 long trips, of 170 miles each. So that’s 170,000 miles that costs you $21k for the battery. Usually it is more than the electricity to change the car to go 170k miles cost. EVs cost more that ICE vehicles because of that $10,000+ battery pack. $10,000 can make a gasoline hybrid go 128,000 miles with fuel at $3.50 a gallon, and that includes the tax to pay for the roads.
It would take a good 5 minutes for your engine to warm up. That leaves you with 5 minutes of deflosting. My point is cost. Warming up the car at home and plugged in cost you money. In an ICE car the heat from the engine is free, assuming your already driving. Put an electric space heater on a metal tray in your ICE car and run it in hour before driving if you have to. Yes that is one situation were the electric car works better. It goes to full heat instantly and draws power from its charging cord, whereas an ICE car has to run its engine and waste fuel to provide heat in your driveway. I never need to warm up my car for more than a couple minutes in the winter.