Land usage is what makes nuclear the most ecologically sound solution. Solar and wind play their part. But for every acre of land, nuclear tops the chart of power produced per year. And when you’re trying to sate the demand of high density housing and businesses in cities, energy density becomes important. Low carbon footprint is great for solar and wind but if you’re also displacing ecosytems that would otherwise be sucking up carbon, its not as environmentally friendly as we’d like.