Water to electricity conversion is easier, cheaper, the technology is available (see Hoover Dam). The major problem is habitat destruction for aquatic species. Water is more dependable, and the amount of energy available for conversion is dependent on rainfall, a heat driven earthly property. Beavers would love it, eco-nazis would be driven nuts by it. You could design small, self contained portable units that could be carried in by backpack, set up and aimed by a techie with little or no understanding of how it works or why or what it does, and made to last a hundred years. Imagine primitivized people in an ice age hunting them down as "tools of the Devil"; gee, what fun.

I'll have to try that one on and see how it works out.