In largest-ever investment, Google nearly doubles its clean energy use

842 megawatts is a lot of energy. It’s more than enough to power all the homes in the Denver metro area. It’s also enough to keep about 15 percent of Google’s data centers humming.

On Thursday, Google announced that it had finalized contracts to buy 842 megawatts of wind and solar energy from plants in the US, Chile, and Sweden, nearly doubling the company's total clean energy capacity.

The contracts range from 10 to 20 years, and Google says they help to give the energy companies financial stability to be able to build additional clean energy facilities. Counting these new sources, renewable energy now provides about 37 percent of the total energy consumed by Google’s data centers worldwide. 

This purchase is the largest of its kind ever made by a non-utility company, but Google isn’t the only tech giant shifting over to clean energy. One of Facebook’s five data centers is powered entirely by a nearby wind farm, and the company says it plans to get 50 percent of its energy from renewable sources by 2018. Amazon’s cloud computing division announced last year that its operations would eventually be powered completely by clean energy. And in 2014, Apple announced that all of its offices, stores, and data centers in the US were being powered by solar, wind, and other renewable sources. 

These shifts are motivated by environmental concerns, at least in part, but they’re also good for companies’ bottom lines. Google said that the renewable energy contracts helped the company keep its energy costs down. And analysts estimate that Apple will save hundreds of millions of dollars over the next 25 years as a result of its investment in a California solar farm.

Energy prices are expected to rise significantly over the next few decades, especially in California, where many tech companies are headquartered, so securing long-term contracts for renewable energy now might end up saving Silicon Valley even more money in the long term.

Google was one of 13 large companies that collectively invested more than $140 billion in new clean energy projects in July as part of the American Business Act on Climate Pledge. The public-private partnership is aimed at adding more than 1.6 gigawatts of renewable energy to the grid; Google also committed to triple its purchases of clean energy by 2025. Apple and Microsoft were also part of the pledge; both companies said their operations would eventually be 100 percent powered by renewable energy.