Google has today taken top spot in Greenpeace’s annual Cool IT Leaderboard ranking technology firms’ environmental efforts, seizing the crown from networking giant Cisco.

The influential campaign group said Google had climbed to the top of the table on the back of its high profile investment in renewable energy projects and its vocal support for US clean energy policy and EU efforts to increase the ambition of its climate change targets.

However, the group again turned its fire on Apple, refusing to include the firm on the leaderboard on the grounds that it does not meet the ranking’s criteria.

“[Apple] has not demonstrated leadership or elected to pursue market opportunities to drive IT energy solutions that many of its competitors have, despite record profits and large cash reserves,” the campaign group said in a statement.

Facebook was also excluded from the list, but Greenpeace confirmed it would be included in next year’s list after the social networking giant announced late last year that following a high profile campaign against the company’s reliance on coal-fired power it would adopt a new policy to source renewable energy wherever possible.

Greenpeace International IT analyst Gary Cook said that the ranking of 21 global technology firms highlighted the crucial role IT firms can play in cutting global greenhouse gas emissions.

“Technology giants have a real opportunity to use their power and influence to change how we produce and use energy - Google tops the table because it’s putting its money where its mouth is by pumping investment into renewable energy”, he said in a statement.

“The IT sector might like to consider itself forward-thinking, but it is keeping far too quiet while the dirty energy industry continues to exert undue influence on both the political process and financial markets”.

Google was followed in the table by Cisco, which dropped from its previous top spot, and Ericsson and Fujitsu in joint third place.

Dell was also praised for sourcing over a fifth of its energy from renewable sources, while Japanese telecommunications company Softbank was also highlighted for the role it played in demanding a shift towards renewable power following the Fukushima disaster.

Business software giant Oracle received the lowest ranking of the firms listed, primarily due to its refusal to disclose information on renewable or carbon intensive energy use.

Cook urged more IT firms to use their status as innovators to step up investment in greener technologies and business models.

“The IT industry must use its influence, innovative spirit and technological know-how to overcome the dirty energy companies who are holding on to the status quo, and holding us back from a transition to a renewable energy economy”, he said. “What we’re seeing is a lot of talk from companies about moving toward clean energy, but so far, not much of action.”