Intellectual Ventures, the high-level think tank created by ex-Microsoft chief scientist Nathan Myhrvold, is going nuclear.

The firm is getting prepared to spin out a company called TerraPower that will develop nuclear reactors that run primarily on natural or depleted uranium, rather than enriched uranium. With un-enriched fuel, the reactors could be loaded up with fuel and sealed for 30 to 60 years. 

Switching from enriched fuel would reduce risks associated with nuclear proliferation and transportation as well as reduce the amount of nuclear waste primarily because the stockpile of uranium would go farther. Depleted uranium is a waste product in the enrichment process. TerraPower's reactor needs some enriched uranium, but only at the beginning to initiate a reaction. 

The switch could also mean that the available supplies of uranium could be exploited to provide power for centuries or even thousands of years, according to the company, far longer than what can be done with enriched uranium.

The reactors will ideally vary in size from a few megawatts, big enough to power industrial sites or small cities, to large multi-gigawatt reactors that can power a major city. Terrapower is also looking at thorium reactors, which do not release plutonium as a byproduct. That would further reduce any risks associated with nuclear.

Like it or not, nuclear is making something of a comeback worldwide. The U.S. Nuclear Regulatory Agency expects to receive approximately 30 applications for new reactors over the next few years. Proponents say nuclear is clean and inexpensive and safer than it was in the past. Critics say it still isn't cost effective.

Threading that gap are new startups like TerraPower and Hyperion Power Generation, which is also developing a small nuclear reactor. Some companies such as General Fusion want to do fusion reactors.

TerraPower emerged from the invention sessions the company runs. Intellectual Ventures gathers scientists from universities like MIT, independent researchers and private enterprise to come up with ideas that can be turned into inventions and companies. Typically, the group shoots for ideas that might have a major impact on society several years from now. (Here's a feature on them).

Intellectual Ventures then applies for patents on these ideas and forms companies when possible. Intellectual Ventures is somewhat controversial in technology circles. Critics say that the company files for patents (and buys patents from ailing companies such as Transmeta) to sue corporations and/or extract royalties. The term "patent troll" is often applied to the company.

Myhrvold, however, tells a different story. The people involved in Intellectual Ventures are primarily scientists, and often well-regarded scientists who have won major awards. They aren't marketing and sales experts. Major corporations have gutted their research departments. Thus, the company really exists to fill a gap that has occurred in the market. The scientists gain freedom from having to build a full-fledged company and large corporations don't have to worry about recruiting high-priced talent.

The company will be run by John Gilleland, who is the manager of the nuclear program at Intellectual Ventures. Before Terrapower, he was the CEO of Archimedes Technology Group, where he focused on the development of new technologies for mitigating waste from nuclear weapons, reprocessing spent reactor fuel, and enriching uranium. Before that, he was at Bechtel and the managing director at the International Thermonuclear Experimental Reactor program.

Correction: An earlier version of this story misspelled TerraPower.