Comment Re:Hydroelectric dams (Score 2) 11
Planning permission. Especially so in Europe, maybe not such a problem with Trump, apart from the fact he *hates* anything "green".
Geology. Not all ground is suitable for building a heavy structure like a dam, or retaining the water it would hold back, reducing the number of glaciers this could apply to somewhat, and a proper survey can take a lot of time. You definitely do not want to build a dam on unsuitable ground.
Geography. You'd need to be able to get construction materials to the dam, and multiple glaciers may run off into the same valley, reducing the number of potential locations for hydro even further. Also, in the kinds of places where you find a lot of glaciers (mountainous regions, duh!), the valleys tend to be heavily used for things like habitation and agriculture, which would need relocating first.
The clock is ticking. Once the glaciers are gone, your dams are only going to be dealing with runoff from precipitation. Which isn't what it used to be where the glaciers are or the glaciers wouldn't be shrinking in the first place.
So, even with a viable location, you've got to get planning permission, relocate anything in the way, build the dam & turbines, connect it to the grid, and generate as much electricity as you can before... Oh, wait, wasn't there a glacier up there when we started?