Apple leads other companies in its use of renewable energy, according to a scorecard released Tuesday by Greenpeace.
The environmental group gave apple a perfect score on its "clean energy index" which is a combination of the estimated size of a company's electricity demand and the amount of renewable electricity being used to power it.
Other companies like Yahoo, Facebook, Google and Microsoft rank behind Apple's perfect score. Microsoft, according to the group, slipped further behind as it invests more into cloud technology.
Ebay ranked lowest on the group's clean energy index.
"The rapid transition to streaming video models, as well as tablets and other thin client devices that supplant on-device storage with the cloud, means more and more demand for data center capacity, which will require more energy to power," Greenpeace said in the report.
The environmental group scores companies on four issues, including energy transparency, renewable energy commitment, energy efficiency, and renewable energy deployment.
The advocacy group said Google's attempts to hit 100 percent renewable energy use is being hindered in some states and other countries by local utility company policies.
Amazon has committed itself to a goal of using total renewable energy. But Greenpeace said, "unlike similar commitments from Apple, Facebook or Google," Amazon's commitment "does not yet appear to be guiding Amazon's investment decisions."
Greenpeace said it developed its clean energy index in "response to the lack of useful metrics and publicly available data," adding that many companies are unwilling to provide the basic information.