[cogman10]

> I believe geothermal has high capital cost and low running costs

Higher capital costs, but not nuclear high capital costs.

> That means it's competing against batteries, which are also great for smoothing out daily cycles, and are very inexpensive.

It likely would supplement batteries rather than compete against them. A battery buffer would allow a geothermal plant to slowly rise to load and fall as that load goes away.

A very large battery can store 200MWh worth of energy. The largest geothermal plant produces 1.5GW. (A lot of the large plants look like they are in the range of 100->200MW). Presumably those plants can run for more than a few hours which ultimately decreases the amount of batteries needed to smooth out the demand curve.

[ZeroGravitas]

A very large battery storage site, like the top 10 currently running has an order of magnitude more energy storage than you suggest.

The largest under construction for go live in 2027 has another order of magnitude, 19000MWh and will deliver up to 1000MW.

Things are changing fast as battery prices drop and experience accumulates.

[mapmap]

Is that correct only 1MW of power but 19,000MWh of storage? That would take over two years to drain it.

[ZeroGravitas]

Well spotted, I've corrected to 1000MW (or 1GW).

The UEA are aiming for a longer than usual runtime, but only 19 hours, not 2 years.