Google has announced it will power its entire global operations using energy from renewable sources next year.

In a move that the search and advertising giant is hailing as “a huge milestone,” 100 percent of the 2600 megawatts or so that Google’s parent company Alphabet needs to power its data centres and offices around the world will be acquired by solar or wind energy.

Google is already the world’s largest private buyer of energy from renewable sources, leaving Amazon in a distant second, and it used renewables to meet 44 percent of its needs last year. The decision has been taken in part for cost reasons, as the price of renewables has recently tumbled, but its European head of energy Marc Oman insisted that it isn’t “about greenwashing” (or presenting an environmentally responsible image).