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Comment Snow powered engine? (Score 1) 32

Either they are running a turbine or engine on CO2 snow, or they are burning natural gas to get the supercritical CO2 fully vaporized.

You have seen what happens when a CO2 fire extinguisher discharges, right?

Compressed air storage has the same problem but less so. Expanding air is cold and you get much lower pressure than expected. So they reheat it with a natural gas burner.

Comment Re:Cold weather performance? (Score 1) 173

So you save energy by using an electric heater all night to keep a battery warm enough to function at all. I detect a logical problem there.

And if you don't have a charger that you can leave plugged in all night then what? You aren't going anywhere in the morning?

If you can get the car moving in the morning, after a say 30 mile commute, then you park it in the company parking lot, I assume the car will discharge the battery as needed to keep the battery warm. After a 9 hour day sitting in a brisk wind at say -15 C how much charge would that expend? Can you still get home?

By the way, the LFP batteries I looked said -5 C for lowest discharge temperature. Those were not car batteries though.

Comment Re:Morbo Voice: (Score 1) 190

Even if the AC would have infinite efficiency (instead of typical values of 2-3), you are increasing temperature out-of-the-house by reducing temperature in-house

So then, you can just shut off your AC and just have it permanently cooler inside, right?

Wait, no you can't?

That's right, because heat leaks back into the house from the outside - warming your house, and cooling the exterior. And the amount it cools the exterior is approximately equal to the amount you're pumping out. Only the energy used by the AC is actually changing the outdoor temperature. But it's utterly dwarfed by the impact of the sun.

(I stress "approximately because there's some slight radiative balance changes - the heat outflow is a point source while the inflows are diffuse, and thermal radiation is proportional to the temperature to the fourth power - but it remains a trivial factor in practice)

Comment Re:Wait, what? (Score 1) 190

Physically, we're non-continental. There is no "continental shelf" here. We're not on continental crust. We're a part of the Mid-Atlantic ridge, the Atlantic seafloor, that protrudes above sea level. We're MORB, not granitic crust. Tectonic plates != continents. The North American plate for example contains large amounts of both continental and oceanic crust.

And yes, geopolitically, we're entirely European.

Comment Re:Wait, what? (Score 1) 190

"Even in North America the Pacific North West region traditionally has never needed air conditioning simply because heatwaves are rare and the region is very temperate. Even reaching the mid-80s during the peak of summer was something that happened for maybe a few days in the past."

That is true for the coast, but definitely not true for the areas east of the Cascades.

Comment Re: Wait, what? (Score 1) 190

I'm in eastern Washington and have a mini-split heat pump. It spends most of its time in heating mode, but since it can get over 100F here the cooling mode is appreciated. So far this year AC mode has been used 9 days. Last year it was used for 22 days.

Heating mode is from mid October to the end of April. It definitely saves money compared to the baseboard electric heaters. There is no natural gas service here.

Comment Re:Wait, what? (Score 1) 190

** Of the places I've visited on the mainland. Ireland, England, Scotland, Holland, Germany, Austria, Czechia... wait, I do remember that my hotel in Paris didn't have AC, and I was utterly miserable there. Czechia and Austria were in the winter / early spring so one wouldn't notice. But I'd think I'd remember if the others had it or didn't...

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