Apple recently updated their environmental progress page used to chronicle their mission of achieving 100 percent renewable energy. For all of Apple's corporate facilities worldwide, they are at 75 percent renewable energy - a 114 percent increase since 2010.
In order to reach 100 percent, Apple said they are constructing new energy efficient buildings and updating existing facilities. They plan to use renewable energy sources like solar arrays and fuel cells while establishing as many long-term contracts with energy suppliers as they are allowed to.
A number of facilities including all of Apple's data centers that provide online services to customers have already achieved this milestone. Facilities in Austin, Cork, Munich and the headquarters in Cupertino are also running on 100 percent renewable energy.
The company's data center in Maiden, North Carolina, was designed from the ground up and has earned the LEED Platinum certification, something that no other data center of this size and type has achieved according to Apple. The center contains a chilled water storage system, the use of "free" outside air cooling via a waterside economizer, extreme precision in managing cooling distribution for cold air containment pods and power distributed at higher voltages to reduce power loss.
The environmental progress page as a whole is worth a visit as it chronicles the company's efforts through the years starting when they released and implemented the policy in 1990.