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by Guvante 1828 days ago
So I did the math and the average water tower holds something like 1/2 kWh worth of power. (50m tall, storage of 1m gallons, efficiency of 90%)

Hydro power storage is fantastic but needs truly ridiculous amounts of water and height deltas to make sense.

3 comments

Must have been a bad calculator. It claimed 1000L/s was 400W.
You’re telling me I could fill a typical water tower in 1 hour with a 500 W pump running off a kitchen outlet?
500W is a lot, it is hypothetically enough to move 10 liters of water 50 meters up every second. A motor on a cycle an electric bike is 250w.

A kitchen tap provides like what, 0.2 liters per second?

So in an hour that's 36000L of water pumped up into the hypotheticals 1 million gallon tank. Right on the three orders of magnitude short that a previous commenter pointed out.
Sounds like they confused W and kW then?
Really good sanity check concept!
Calculator said 400W for 1000L/s and my mental sanity check missed the duration units and thought 400W can move a ton of water.
You probably made a mistake somewhere.

3.8Mg * G * 50m ~ 1700M Joules which is about 500kWh.

I suspect the k in kWh leads to the occasional factor of 1000 error.