Google: These five datacenters are now running on carbon-free clean electricity

Google says all its infrastructure will go green by 2030.

Google has revealed that five of its datacenters are now running almost entirely on carbon-free 'clean' electricity.

According to Urs Hölzle, Google's senior vice president of cloud infrastructure, the search and ad giant buys power from more than 50 renewable energy projects, and has a capacity of 5.5 gigawatts, which equates to about one million solar rooftops. 

Google announced the update in line with this week's Earth Day on April 22, a campaign to raise awareness about environmental issues that has been running since 1970. Data centers that power the cloud have become a major source of carbon dioxide (CO2) emissions and tech giants have been showcasing their progress in making the infrastructure that delivers email, productivity apps, e-commerce and games less harmful to the environment. 

SEE: IT Data Center Green Energy Policy (TechRepublic Premium)

Google CEO Sundar Pichai today noted the company's existing goal of operating entirely carbon-free by 2030 rather than offsetting its carbon footprint. 

"Within a decade we aim for every Google data center, cloud region, and office campus to run on clean electricity every hour of every day," writes Pichai. 

According to Pichair, five data center sites in Denmark, Finland, Iowa, Oklahoma and Oregon are now operating "near or at 90% carbon-free energy".

Google has so far locked in around $4 billion to buy clean energy from more than 50 wind and solar projects globally until 2034. 

It's not alone in making its infrastructure greener. Cloud rival Amazon announced this week it was launching nine new "utility scale" wind and solar energy projects in Canada, Spain, Sweden, the US and the UK as part of its Earth Week message. 

The projects supply renewable energy to Amazon's corporate offices, fulfillment centers, Whole Foods Market stores, and Amazon Web Services (AWS) data centers. 

Amazon claims it is now the largest corporate buyer of renewable energy in Europe, with more than 2.5 gigawatts of renewable energy capacity, or enough to power more than two million European homes a year.

Amazon kicked off its biggest ever renewable energy project in February with an offshore wind farm about 20 kilometers off the shores of the Netherlands. It's projected to go live in 2023; Amazon is also aiming to use 100% renewable energy by 2030. 

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Google, Adobe and Hewlett Packard are backing a lobbying effort by the Clean Air Task Force and the Environmental Defense Fund for the US federal government to move totally to clean electricity sources. The government spends half a trillion dollars on electricity every year.

Amazon is creating a solar-based system with energy storage in California's Imperial Valley that will generate 100 megawatts (MW) of solar energy, or enough to power 28,000 homes for a year. It includes 70 MW storage capacity.    

It's backing a wind energy project in Oklahoma capable of producing 118 MW of energy located in Murray County.