Comment by LeFantome
3 hours ago
Where I live, hydro is the dominant power producer.
My electricity costs 40% less from 11 pm to 7 am and 30% more from 4 pm to 9 pm.
A hydro dam can also be thought of as a battery. When you are not using it, the dam fills up (charges).
My utility buys inexpensive excess power from the NA grid when electricity is cheap and drains the dams when third-party electricity is expensive. Adding other renewables to the mix plays a similar role. The pricing incentives shrink peak demand as you suggest.
One of the reasons residential solar is a tough sell for me is that electricity is relatively inexpensive and likely to stay that way.
There are interesting large scale projects that use hydro directly as power storage for renewables.
When the sun is out or wind is blowing, use excess energy to pump water up hill. When you're low on energy supply, open up the dam to run the water back down hill and through a hydro plant.
I've toyed with the idea of doing the same thing at a small scale on our farm but would need to build a second decent sized pond up hill of our main one.
I've read that globally almost all the places that can do pumped hydro "storage" already exist. I don't know if that's true, but if it is, then while this is a really cool technology, we won't be getting much further with it.
Have you priced residential batteries and time of use to charge at night? That's Base Power's value prop, they partner with ComEd, install batteries at your home and become your power provider charging a lower rate than ComEd. Batteries charge at night when nuclear generators are still humming and demand is low, and then serve daytime load.
Solar may not pencil out, but energy arb over system lifetime might, especially if you have any battery subsidies available. Just keep in mind flexibility to add solar in the future so its as trivial as installing racking and panels and running power to the storage and load center (optimize for optionality).
https://www.chicagotribune.com/2026/07/28/base-power-battery...