Greenpeace has released their Clean Energy Index for 2015, and Apple has topped their tech company rankings for using renewable energy to power their cloud services.

Apple and related companies are rated on the kind of energy they use and several other factors. These include transparency, the company's commitment to to renewable energy, energy efficiency, and deployment. Apple rated an "A" in all categories, and was noted for using 100% renewable energy to power its cloud services.

From Greenpeace:

Apple continues to lead the charge in powering its corner of the internet with renewable energy even as it continues to rapidly expand. All three of its data center expansions announced in the past year will be powered with renewable energy. Apple is also having a positive impact on pushing major colocation providers to help it maintain progress toward its 100% renewable energy goal.

Apple has been aggressive in their adoption of clean energy solutions for their data centers, including the construction of a new solar farm in California that will power their new Apple Campus 2, along with several of their other properties in California. The company also recently announced a new clean energy initiative for their manufacturing facilities in China.

Source: Greenpeace