Comment by mikeyouse

2 days ago

They could also run their AC to below where their normal set point would be to “bank” some of the free electricity. I wonder if we’ll start seeing other more passive energy sinks… if you lived in a hot area and could rely on several hours of free electricity each day, it enables all sorts of interesting options like turning on a secondary cooling system to “charge” a large boulder or hunk of metal that you could then pass air over to cool your house when energy is expensive again.

If you built homes with a lot of thermal mass, you could cool the internal thermal mass when energy is $0 and have that mass absorb heat the rest of the day. This is sort of the principle a lot of traditional architecture uses where evaporation, wind over a courtyard, or nighttime lows cool thick walls.

  • Yep, our house was built like this but in a cooler climate (large windows facing south with the all of the stone flooring and surfaces getting direct sunlight in the winter). But since most houses in the Aussie suburbs aren’t really optimized for this, you’d have to retrofit many million houses to take full advantage. Opens up some interesting opportunities for sure.

    • Yeah, for sure. Building for 0 carbon AC and electric resistive heating will probably look a little different.

  • This is how the cold storage caves work in the Midwest. They run their ammonia loops harder in the off hours and let the cave mass handle it(provided a large enough area is kept frozen, otherwise thermal expansion cycling can cause a carve out in the ceiling).