The billionaire investor Warren Buffett has agreed to buy a solar power farm in California worth $2bn

The billionaire investor Warren Buffett has agreed to buy a solar power farm in California worth $2bn (£1.3bn).

Buffett's MidAmerican Energy Holdings will take over Topaz Solar Farm, which is expected to produce enough power to run 160,000 homes when it is up and running in 2015. The farm, halfway between Los Angeles and San Francisco, is the world's second-largest photovoltaic plant under construction and is expected to generate 550-megawatts of electricity or about half the power of a nuclear reactor.

The deal comes hot on the heels of a string of green energy investments by the famous investor. MidAmerican, which is part of Buffett's Berkshire Hathaway empire, is the largest wind energy provider in the US where it operates more than a dozen wind farms.

MidAmerican sealed the deal for Topaz on Wednesday, a day after the seller, First Solar, failed to secure a US government loan guarantee for the project. The terms of the deal were not disclosed, but First Solar's difficulties securing funding for the vast project suggests Buffett probably got a good deal. First Solar will continue to build the farm on behalf of Berkshire and it is due to open in early 2015.

Greg Abel, chief executive officer of MidAmerican, said: "[Topaz] demonstrates that solar energy is a commercially viable technology without the support of governmental loan guarantees."

Analysts suggested Buffett is moving from wind to solar power to take advantage of lucrative tax breaks. Gerard Reid, an analyst at Jefferies, said: "The reason for the move from wind to solar is very simple. Tax credits for wind in the US expire at the end of next year, while solar ones run till 2015."

In February Buffett, the world's third-richest man, said he was keen to make a fresh wave of "major acquisitions". "Our elephant gun has been reloaded, and my trigger finger is itchy," he told investors in his annual letter to shareholders.Last month he ended his moratorium on investing in technology, taking a $12bn (£7.5bn) stake in IBM, the 100-year-old tech firm. Berkshire Hathaway has been buying shares in IBM since March and now owns 64 million shares, or about 5.4% of the outstanding stock.