How Water Heaters Have Evolved into Grid-Scale Energy-Storage Devices (2014)

Re:How Water Heaters Have Evolved into Grid-Scale Energy-Sto... by ajross on Sunday January 27, 2019 @10:16AM (#19011979)

Not sure you're disagreeing with me. That's indeed how they work, and it's... a pretty neat trick! So are phototransistors, for that matter. Not sure I'd put radiative solar water heaters in the same boat, but semiconductors and thermodynamics make for great tricks.

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Re:How Water Heaters Have Evolved into Grid-Scale Energy-Sto... by SigmundA on Sunday January 27, 2019 @10:44AM (#19012073)

I am disagreeing with "They don't make "heating" any more "efficient" per se."

They definitely do make it more efficient at least in the ways that matter to people, less energy paid for the same heat.

I guess all technology is a trick, but normally that denotes its not really doing what is said, which you reinforced by saying it is not more efficient.

Air source heat pump water heaters and direct solar water heaters are similar in they both utilize solar energy to heat water. Then again if you really get down to it you could argue everything is indirectly solar powered, just some forms you must pay for the energy, while heat pumps and solar collectors get it directly from outside your home heat pumps just require some energy to collect it.

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Re:How Water Heaters Have Evolved into Grid-Scale Energy-Sto... by dannypgh on Sunday January 27, 2019 @01:32PM (#19013009)

I think you just mean different things by "heating" - if you're talking about heating in a closed system, they're the same - 5 joules of energy are needed to increase the total heat energy by 5 joules, with either approach.

The advantage of the heat pump is that we are, for, say, 3 joules of energy, heating part of the system by 5 joules and heating the other part of the system by -2 joules.

This is great for home heating and the like because we don't care about making the outside slightly colder.

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Re:How Water Heaters Have Evolved into Grid-Scale Energy-Sto... by SigmundA on Sunday January 27, 2019 @04:29PM (#19013900)

Good thing we don't live in a closed system and instead have a giant fusion reactor in the sky to heat the outside air.

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Re:How Water Heaters Have Evolved into Grid-Scale Energy-Sto... by thatcat on Sunday January 27, 2019 @10:54AM (#19012122)

Whether it seems like a trick or not depends on your background.

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