It was hard to figure out what the author's main points are, but it seems that they are upset because (paraphrasing) "environmentalists are against nuclear energy". Meanwhile, the author sees nuclear energy as part of the solution to moving away from fossil fuels.

I think both, the author and the author's antagonists, are right: it'll take a diversified source of energy (nuclear, solar, wind, geothermal, etc) to ween the world off of burning shit, however it's very likely too late to mitigate the problems we're going to face as a result of human-induced climate change.