By Marlize van Romburgh Friday, March 23rd, 2012

Microsoft founder Bill Gates, right, spoke with the Wall Street Journal's Alan Murray about his vision for a nuclear-led clean energy future at the annual Eco:nomics conference in Goleta.

Microsoft founder Bill Gates is placing his chips on nuclear technology these days — even as he’s skeptical about the time horizon for a fossil fuel-free world.

Gates, who has about 6 percent of his personal money in energy technology, said that he’s investing in fourth-generation nuclear research but doesn’t expect the world to draw the majority of its energy from clean sources within the next 75 years.

“People underestimate how hard it is to make these changes. They look at things that are deeply subsidized. They look at the richest areas and not low-income areas. I think it’s way harder than many people think,” he said.

Gates spoke at the Wall Street Journal’s annual Eco:nomics conference in Goleta on March 22.

He is one of the primary investors in fourth-generation nuclear company TerraPower, which is researching so-called traveling wave reactors that use the depleted uranium waste from older nuclear plants to generate electricity.

In addition to being a cleaner, cheaper source of nuclear power, the TerraPower plants also “require no humans,” Gates said. The plant design means the reactors could go 40-60 years without refueling.

Gates said the company expects to build its first nuclear reactor by 2022, although it would likely be built outside of the U.S. in countries with less stringent nuclear regulations. The governments of China, Russia and India have already expressed interested in TerraPower’s technology.

The U.S. may have “to fall behind” other industrialized nations before it catches up again, he said, referring to American reluctance to build new nuclear plants.

Gates has also invested in biofuel maker Saphire Energy and battery maker Liquid Metal Battery Corp.

Well known for his philanthropy in education and third-world development through the Bill & Melinda Gates Foundation, Gates said he’s personally investing in a range of clean energy alternatives because he believes in about five “energy miracles” that could lead the way out of climate change.

“We need about 200 crazy people” to come up with those new energy technologies, he said. Nuclear, biofuels, solar, wind and natural gas — which has already experienced its own miraculous resurgence in the U.S. — all offer some hope.

Gates is a limited partner in Khosla Ventures and referred jokingly to founder Vinod Kholsa, who spoke at Eco:nomics earlier in the day, as “the pay master of crazy people — some of whom we’ll declare sane at some point in the future.” In his talk, Khosla advocated for wood chips as one viable and cheap potential energy source.

Solar and wind, while promising, will only be supplementary to more consistent and reliable energy sources such as nuclear, Gates said. “We’re addicted to reliable energy,” he said.

Storage and transmission of energy from wind and solar remains a drawback, he said. Any government subsidies for wind or sun power should focus on encouraging innovation in storage and transportation of those energies as well.

I would encourage people who work in [clean energy] that the importance of this is right at the top,” Gates said. “The reason I spend time on it is because I think it is so critical to the environment and for helping the poorest. Cheap energy — it’s like a vaccine in terms of what it can do to help improve livelihoods.”