Storing Solar Power on my ROOF!!!

Sounds like this one: [VIDEO] They do say it is about equivalent to a single AA alkaline. It is not exactly an optimized efficient setup, but still, it gets the point across. Pumped hydro is a grid scale option, in places that have the ability to store a lot of water.

There is a great youtube channel that tests out different energy storage and harvesting setups, a lot of them focused around water. This is one where they use solar to pump water to the roof, and then use the potential energy overnight: [VIDEO]

Here's some "slow math" in video form ;) [VIDEO] I find him entertaining. Put a 55 gallon drum on his roof, pumping water up via solar and running lights at night. Closed loop system. He also "does the math" and mentions exactly what you are saying in entertaining format. Just not worth it if you're not doing it on a massive scale, preferably way out of sight and danger.

> maybe they mean 2 MWh, but if that's the case, it is a joke. That's like 30 Teslas cars Reminded me of the punchline to this water storage video: [VIDEO] That guy went mechanical with rocks: [LINK]

Relevant video on a pumping water on the roof + turbine system : [VIDEO] It's quite far from powering your whole house tho !