Good, given the right geography.

- Hydrothermal: great if you're in Iceland, or near Yellowstone, or other such place blessed by heated rock being close to the surface. Not as great if you need to drill 7 km to reach it.

- Hydro: great if you have a lot of mountains and rivers, like Switzerland or Norway. Harder if you don't, like in much of Texas, to say nothing of Florida.

- Tidal: great if you have a sea shore, preferably with narrow bays / fjords. But if you're in a place like Turkmenistan (one of the two doubly-landlocked countries), you resort to drilling for and burning methane %)