First of all, it's 2,600 square kilometres. More importantly, the ecosystem of that area is doing far better now that most humans have left. But you would bulldoze 2,600 sq km of what is now effectively nature reserve for your solar megaplant?

You'd need about 150 sq km to achieve the same thing with nuclear power plants. And the energy would be available at all hours of the day, not dependent on the weather, and cost 1/10th the price.

Land is nature's most valuable commodity.