Most major tech companies have been boasting about how green their energy is, hoping to ward off critics that point out how much power their ever-growing network of huge data centers use. But there’s an independent report card, and it shows that not all of them are getting good grades.

A report from Greenpeace called “Clicking Clean: Who is Winning the Race to Build a Green Internet?” gives A grades to Google Inc., Apple Inc. and Facebook Inc. It cites their use of power from renewable sources, as well as hydroelectric power. It also assesses how open and transparent a company is about its energy sources and planning, as well as how much firms advocate for the use of clean energy.

However, Amazon.com Inc. got a C, despite efforts such as building massive wind farms in Texas and South Carolina, mainly because it drew a failing grade for transparency. “Amazon continues to talk a good game on renewables but is keeping its customers in the dark on its energy decisions.” Greenpeace USA Senior IT Analyst Gary Cook said in a release. “This is concerning, particularly as Amazon expands into markets served by dirty energy.”

Amazon was far from alone in its lower grade, however. Chinese companies Baidu Inc. and Tencent Holdings Ltd. each got an F, and Alibaba Group Holding Ltd. got a D. So did Samsung Electronics Co. Ltd., Oracle Corp., Netflix Inc., Vimeo Inc., Spotify Ltd. and HBO. HP Inc. and Korean search engine Naver Corp., among others, received C grades.

The Greenpeace report also laid out how much power it takes to keep the Internet going. According to the report, the information technology sector’s global energy footprint is already about 7 percent of the world’s electricity. In a few years’ time, says the report, that will increase threefold, while our hyper-connectivity will mean the Internet will be a much hungrier beast.

“A fully renewably powered internet will not happen overnight, but for sector companies to adopt a 100 percent renewable commitment is an important first step,” said the report. In the next paragraph, the report warns that tech corporations will have to be more active, and vocal, than ever regarding renewable energy in view of U.S. President-elect Donald Trump’s promise to “roll back climate policies and revive the use of coal.”

Here’s a partial chart of company grades from the report:

Image courtesy of Greenpeace

Featured photo credit: Sander van der Wel via Flickr