Bill Gates makes surprise investment in clean tech start-up LightSail Energy

Microsoft co-founder Bill Gates has made a rare investment in a start-up, pouring funds into US clean tech company LightSail Energy, in a $37.3 million funding round that also includes PayPal co-founder Peter Thiel.

LightSail, founded in 2009, is based on the research of chief scientist and co-founder Danielle Fong, who, according to Electronic Engineering Times, began work on her PhD at the age of 17.

Based in California, LightSail is attempting to apply thermodynamics to develop energy storage based on compressed air.

“Compressing air creates heat energy. Until now, this was wasted, drastically reducing efficiency,” LightSail says on its website.

“Our innovation [is] an elegant method of capturing this heat energy and regenerating useful energy from it.”

“We inject a fine, dense mist of water spray which rapidly absorbs the heat energy of compression and provides it during expansion.”

The start-up has closed a $37.3 million Series D funding round from major names including PayPal co-founder Peter Thiel, Khosla Ventures, Innovacorp and, unexpectedly, Bill Gates.

According to LightSail co-founder and chief executive Steve Crane, the fresh funds will enable LightSail to “bring its first grid-scale energy storage products to market”.

The first shipment is expected in the fourth quarter of 2013. According to Khosla Ventures, LightSail is on the brink of achieving a world first.

“When deployed, LightSail’s technology would… make renewable energy practical and mainstream for the first time,” founding partner Vinod Khosla said in a statement.

The latest round of funding takes LightSail’s total funding pool to more than $52 million.

It’s important to note both Gates and Thiel invested as individuals, not through their investment vehicles, although the amounts they put forward are unknown.

While Thiel is well known for his involvement in the start-up scene, Gates has long been commended for his philanthropic contributions.

In 2000, Gates and his wife combined three family foundations to create the Bill & Melinda Gates Foundation, which is the largest transparently operated charitable foundation in the world.

As of 2007, Bill and Melinda Gates were the second most generous philanthropists in America, having given more than $28 billion to charity.

They plan to eventually give 95% of their wealth to charity.

While Gates rarely makes individual investments in start-ups, it’s been reported the LightSail technology “intrigued” him.

It’s also worth noting Gates is a limited partner in Khosla Ventures, which has been a LightSail backer since it was founded in 2009.

Thiel, meanwhile, has done a complete backflip with regard to his stance on clean technology, after describing it as a “disaster” at a conference last year.

“It’s time to find honest companies that can develop technologies that stand on real innovation,” Thiel said in a statement.