One of the reasons why Apple is able to ensure that their data centers are green is because these data centers are usually built from ground up by Apple, and in a location far away and usually isolated. This is compared to Apple Stores which are usually part of a mall or in the middle of a city where it might not be as convenient to go green. About a week ago, Apple’s VP of Environmental Initiatives, Lisa Jackson, mentioned that Apple could be interested in their retail stores being powered by renewable energy in the future, but admitted that it would be tricky. However in Japan it looks like Apple is working towards that, or at least trying to be as green as they can for now.