Comment by bee_rider
2 days ago
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.
You’re missing the other side of the equation.
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.