The deal will see NRG Solar, subsidiary of generation company NRG Energy, invest up to $800m in the project, expected to be among the largest in the world, during the next four years.

“Solar power is critical to transitioning our nation to having a greater emphasis on large-scale clean energy technologies and it is going to be projects of the scale of Agua Caliente that will help us achieve this ambitious goal,” says David Crane, NRG Energy president and chief executive.

Arizona-based