Founder of Microsoft and the Gates foundation also accuses environmentalists of making misleading claims about the comparative price of solar

Bill Gates has branded fossil fuel divestment “a false solution” and accused environmentalists of making misleading claims about the price of solar power.

In an interview with US magazine the Atlantic, the founder of Microsoft and the Gates foundation criticised the global movement that has seen pension funds, universities, churches and local governments worth $2.6tn commit to pulling their investments out of coal, oil and gas companies.

“If you think divestment alone is a solution, I worry you’re taking whatever desire people have to solve this problem and kind of using up their idealism and energy on something that won’t emit less carbon – because only a few people in society are the owners of the equity of coal or oil companies,” he said. “As long as there’s no carbon tax and that stuff is legal, everybody should be able to drive around.”

The Bill and Melinda Gates Foundation, which Gates founded with his wife, is the world’s largest charitable foundation and funder of medical research. It has $1.4bn (£900m) invested in fossil fuel companies, according to its latest available tax filings.

Divestment campaigners said the criticism was misplaced.

Tim Ratcliffe, a campaigner at environmental NGO 350.org, which has spearheaded the movement, told the Guardian: “No one claims that divestment alone will solve the climate crisis, but it’s also clear that we won’t get anywhere unless we weaken the political power of the fossil fuel industry. If you want to see climate action, you simply cannot continue to invest in companies that are planning to burn five times more coal, oil and gas than our climate can take.”

Gates called on the US government to triple its annual budget for energy research and development to $18bn (£11.7bn), citing the billions invested by the US government and the role of private firms in fighting “the war on cancer”.

“As a percentage of the government budget, that’s not gigantic. In energy, no government – including the US, which is in almost every category the big R&D funder – has really made a dramatic increase,” he said.

He also criticised clean energy campaigners for making “misleadingly meaningless statements” about the comparative price of solar power and fossil fuels.

He said: “What they mean is that at noon in Arizona, the cost of that kilowatt hour is the same as a hydrocarbon kilowatt hour. But it doesn’t come at night, it doesn’t come after the sun hasn’t shone, so the fact that in that one moment you reach parity, so what?”

The move follows an announcement by Gates in June that he would invest $2bn (£1.3bn) in breakthrough renewable technology projects over the next five years, double his investments to date.

In March, the Guardian launched a campaign calling on the Gates foundation and the Wellcome Trust – the world’s largest charitable foundations and funders of medical research – to move their money out of fossil fuel companies.

Volunteers have been persistently campaigning outside the foundation’s visitor centre in Seattle for a month since the city’s former mayor started a campaign asking the foundation to divest.