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Comment by pfdietz | Hacker News Reader

These peaks cry out for demand management. This means exposing customers to actual prices. But how is a homeowner to respond to these? This seems like a great use case for home automation, where systems can be automatically turned up/down, on/off, in response to changes in prices, or even in response to forecasts of changes (so, for example, a home might be precooled to below normal before a large peak, then allowed to gradually warm during the peak with the A/C turned off.)

More complex structured contracts with electricity providers might also be a solution, where consumers pay for only a certain level of reliability in the supply, with the provider being able to throttle power in tight situations.

(Precooling could be extended to making ice. A tonne of ice is ~1 m^3, which isn't that much volume. Storing energy this way could be much cheaper than doing so with batteries.)

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The biggest draw is A/C. It dwarfs other usage. And unfortunately, A/C is sometimes required to avoid death. Precooling isn’t effective in that the A/C will still run for nearly as long during peak.

Precooling allows cheap pre-peak power to be used instead of very expensive peak power.

That's the critical thing. A/C isn't just a luxury anymore. As the Earth heats up, A/C becomes am absolutely necessity to avoid dying from temperatures exceeding the wet bulb temperature, where human sweat is no longer sufficient to cool people off, especially the very young or very old. The heatwaves across Europe a bunch of years back killed some 70,000 people from the heat.

> Precooling isn’t effective

Interesting, PG&E tells me to do it when the temperature is expected to be high. I've done it on occasion and it has seemed to work. I'm sure it's a YMMV situation, depending on insulation and other factors.

OTOH there are plenty of more energy efficient alternatives that avoid death to cooling an entire poorly insulated, oversized house without ventilation energy recovery at peak demand times using fossil fuel generated grid electricity.

Precooling is only viable if homes are really insulated and / or all the electricity comes from renewable as otherwise it will increase the overall energy used (as precooling is less efficient), which will increase CO2 emissions. In think the population also needs to “meet in the middle”, for instance by increasing the temperature of the AC by one degree in summer. This could get automated to offer a best effort service.

Of course precooling is less efficient. But if there are large swings in price that can more than make up for it. And if daytime solar is replacing evening peak natural gas the CO2 emissions are reduced also.

There was another sharp peak on ERCOT this evening, but it was about half an hour long. This is tailor made for demand response. Simply cutting off the compressors of A/Cs for half an hour by remote control would work.

Customers in Texas should look for electricity providers who offer such remote control (there must be some) and are willing to pay you to put them on your A/C.

This is something I have in place in my home right now. My electric car for instance is charging itself at the hours with the lowest prices. If I want I can hook up my water boiler, my A/C etc to the same system. Pretty wild that this isn't already common in the U.S.

ERCOT uses demand management aka demand response: https://www.google.com/search?q=ERCOT+demand+response

I don't know how far that extends, particularly to individual consumers.

I remember reading about the provider Griddy that did exactly that - gave customers the wholesale rate for power. Then the 2021 winter storms hit with the price peaking at the limit of $9 per kWh ...

Yeah, that's the downside. Thus the need for home automation (or else, the ability of the grid company to cut you off if your bill exceeds some value, sorry about the burst pipes.)

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