The FT reported that Google and Microsoft both refused to comment on possible future investment plans, but a commitment to offshore wind energy would fit with their strategies to reduce the cost and environmental impact of their high levels of electricity consumption.
Google has invested tens of millions of dollars into renewable energy research in the US. Microsoft has been taking steps to cut its power consumption, for example by siting its new European "mega data centre" in Dublin, taking advantage of the cold climate to reduce the need for mechanical cooling.
Dominic Maclaine of New Power, an industry journal, said: "Data centre servers have significant power needs, and it is understandable that internet firms are increasingly keen to ensure that the power they buy is seen to be ‘green’."
A huge expansion of offshore wind power will be essential if the government is to hit its target of generating about 30 per cent of Britain’s electricity from renewable sources, but the financial crisis has raised doubts about whether developers will be able to raise the estimated GBP100bn ($160m) of investment that is needed.
He argued that other investors would step in to fill that gap, including sovereign wealth funds from countries in the Middle East or Asia looking for assets in Europe, Chinese and other companies seeking to acquire expertise in offshore wind to take back to their home countries, and the European Investment Bank, as well as energy-hungry multinationals.
Companies such as Google and Microsoft would never finance the majority of a project that could cost GBP1bn or more, he said, but could take minority stakes.
Charles Anglin of the British Wind Energy Association said he expected the next big growth in the industry to be led by large electricity consumers.
"Companies with a big electricity bill will be looking to get into the business and supply themselves," he said.
However, the offshore wind industry is still in its infancy, and costs are much higher than for onshore wind.
Andy Cox, an energy partner at KPMG, said: "At a time when capital is in short supply and everyone is driving down costs, it could be some time before we see US multinationals invest in offshore wind in Europe."
The electricity consumption and greenhouse gas emission caused by the companies is unknown but the huge data centres used by Google and Microsoft, as well as the emissions caused by computers and the internet, are believed to be particularly energy intensive.