Comment by willvarfar
2 days ago
Yes the article talks about consumers scheduling things like washing machines during the day, or even filling up a battery.
2 days ago
Yes the article talks about consumers scheduling things like washing machines during the day, or even filling up a battery.
This is the “smart grid” idea, right? We just haven’t fully explored it yet.
Something I firmly believe is that there’s a ton of low hanging fruit for timing our energy use better. It is just hidden by the desire to present a uniform energy price.
Like why not run our water heaters when power is cheap? Then if that became a thing, we might even be interested in larger water heater tanks. Batteries cost per volume, you only pay for the surface are of a metal tank!
I'm on a time-of-use tariff, with a special "EV" slot between 02h and 05h. My car is programmed to only charge during this time unless I tell it otherwise.
The price difference is significant: About €0.08/kwh compared to the €0.2 - €0.4 I'd be paying during normal day/peak times.
This has made my day-to-day driving basically free, less than a euro per 100km (€0.08/kwh * 7kwh/100km)
I tried doing the same thing for other large(ish) loads in the house, dishwasher, washer & dryer, but the cost benefit was really really small when compared to the big savings from my EV charging.
I heat my water using an oil burning boiler, but if I had an electric water heater, it would make total sense to run that during the "EV" hours as well. If I could, I would then also invest in more capacity, and set the thermostat higher to have essentially a hot water battery that could last me the whole day.
At my old house I had an overspecced solar system, and I set it up to dump the remaining available solar energy after the batteries are done charging into my hot water heater. The thermostat was set to 75C or something, super hot. I'd then have piping hot water for most of the day, and maybe needed a small electric boost in the mornings, especially in the winter. Another 200L or so would have resulted in me not needing any grid power to heat up enough hot water for the household.
Power at peak times is cheap because load is distributed throughout the day. If everybody ran their heaters at the same time, power wouldn’t be so cheap and we’d reach the same situation we’re in.
Power at peak times is cheap because it's the time of highest insolation.
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If power wasn’t cheaper, there’d be no incentive to run our heaters at the same time. I’d expect the market to work this out, and price power down during unexpected over-supply, rewarding nimble workloads. Then there arrives a reward for being nimble, which is something we should incentivize I think.
Think of being able to set a price on Amazon Spot instances where it's low enough to charge your home battery for "free". When the price is right, you recharge your batteries as much as possible. When the price falls outside the range, you leverage your battery to offset the higher electricity prices. This would be part of the "smart" in "smart grids".
Australia has some cutting edge tech that actually sends control signals through the electric wires.
It rolled this out in 1953:
https://en.wikipedia.org/wiki/Zellweger_off-peak
It let coal plants run more efficiently and people could heat their water overnight.
Somewhat bafflingly they seem to have somewhat failed this same task with the solar rollout.
Presumably 21st century capitalism got in the way of the mid 20th century engineering.
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.
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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).
More countries where there's a surplus, are advising people to charge or use electricity during the day.