First-time surprise entrant Wipro tops the list of rankings in the 18th edition of the Greenpeace "Guide to Greener Electronics," with Apple dropping two spots to sixth compared to last year's study.

Greenpeace International has ended a long-running campaign calling on Facebook to "unfriend coal" as a source of energy for its data centers, after Facebook agreed to promote clean and renewable energy, the two said Thursday.

While some consumer electronics manufacturers have cleaned up their act, making more energy-efficient gadgets with fewer toxic materials, others are continuing to make fine promises but no changes, according to Greenpeace. In response, the environmental pressure group is changing the way it scores companies in its Guide to Greener Electronics, placing more emphasis on their actions than their words, and measuring new aspects of their operations.

When it comes to Cloud computing, CIOs are pragmatic, and perhaps cynical enough, to take its Green credentials with a grain of salt. It’s not that sustainability isn’t an issue, but it’s the flexibility and potential savings of Cloud computing that really have everybody excited. It’s probably just as well, because although Cloud companies are quick to play the ‘Green IT’ card, it seems they’re not always so eager to provide information to back up the claims. And as is so often the case when it comes to sustainability, it’s not just a story about energy efficiency — it’s about clean energy.

Apple has long prided itself on the environmental consciousness behind its products, and consistently aims to get greener. But according to Greenpeace's report measuring the amount and type of energy consumed by top tech companies' data centers, Apple is doing a poor job with its energy consumption.