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Comment by slfnflctd | Hacker News Reader

I don't know why power demand is up in TX generally, but I do know that right now a big reason for the demand is because a lot of residences have electric resistance heat only-- which is great for electric blankets, but not so much for heating all the air in your home when it's extremely cold.

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Lived in TX all my life. Every residence I’ve seen has had a heat pump for decades. The the thing is though it switches to resistive heat at something like 20F when they are no longer efficient. Rarely a concern in TX, most of the time we’re complaining it’s over 100F!

Why is it not good for heating? I'm sure resistance based electric heating is very efficient. I've lived in very cold places and the heat has almost always been electric or water heated by electric. You just need radiators. Northern European countries for example use that a lot and the temperatures are often as low as -22F. Of course they build to optimize for low temperatures unlike TX.

It’s more efficient to burn natural gas directly for heat than to use it to generate electricity which is then used for heating. Typical gas turbines are around 40% efficient, plus a few percent for transmission loses. Though apparently there are some cutting edge turbines that are 60% efficient.

It's more efficient, but not more environmentally friendly, given how much of Texas's grid is wind power (and increasingly solar).

Boilers/furnaces are ~90% efficient now. Combined electrical/heat generation can only hit 50-80% efficiency.

In theory heat pumps powered by electricity would be the most efficient option.

Heat pumps don’t work particularly well below 25F. Our heat pump switched to auxiliary heat (electric resistance heating) with how cold it’s been in Texas.

Those are just the standard compressor/r410 systems with reversing valves. There are number of systems designed to work well below 0F.

https://www.mitsubishicomfort.com/benefits/hyper-heating https://www.fujitsugeneral.com/us/residential/technology/xlt...

Theory would require some magical fluid to do the heat transfer, and we're limited to real coolants that don't have horrid environment impacts

Or geothermal heat pumps for very cold and hot environments.

Though, heat pumps lose efficiency in very cold weather, and right now it's very cold in Texas.

Resistance heating is 100% efficient and therefore basically the least-efficient method. Heat pumps have coefficients of performance well over 1.0, even when the outside air is below zero degrees.

It takes enough natual gas to heat three homes in order to generate the electricity to heat one home.

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