It is how individual power generation projects and measured though. If you install a GW of solar generation, it means you installed solar panels capable of generating 1 GW peak. If you install a 1 GW of coal generation, then same thing. If you install 1 GW peaker gas plants etc.

The coal plant will have a capacity factor of 80% though. Solar will be 10 to 20%. And the gas plant could be very low due to usage intent.

Battery projects are the same (since they're reported as generators). Whatever nameplate capacity...for about 4 hours only.