Bill Gates-Backed Nuclear Power Startup, TerraPower, Gets $35 Million

TerraPower Nuclear Reactor

Nuclear power, that oft-maligned source of clean energy, got a boost earlier this year when TerraPower announced plans to team up with Toshiba to build a hot tub-sized traveling-wave nuclear reactor. Now TerraPower is moving even closer to commercialization with news that investors—including Khosla Ventures and Charles River Ventures—are backing the startup with a cool $35 million. TerraPower claims it has already raised tens of millions of dollars, though it won't give exact figures.

Unlike light-water nuclear reactors that run on enriched uranium, TerraPower's traveling-wave reactors run on depleted uranium that only needs to be replaced every 60 to 100 years. Based on known uranium reserves, TerraPower believes that its reactors could power the world for thousands of years without having to chemically reprocess fuel.

TerraPower explains the science behind traveling-wave reactors:

A nuclear fission reactor produces and controls the release of energy from splitting atoms of certain heavy elements. The nuclear power plants of today require a full core of fuel made from enriched uranium. The TWR, in contrast, initially contains only a small amount of enriched uranium, which is used to kick off the chain reaction through a core of depleted uranium. The wave of fission would move slowly through this depleted uranium core, splitting many more of the uranium atoms than a conventional reactor would.

But TerraPower isn't ready to power the world quite yet. The startup is working on a 500-megawatt reactor, according to the New York Times—that's only half the size of conventional reactors planned by other companies. Ultimately, though, TerraPower hopes to build a gigawatt-sized reactor that can light up an entire city (in a good way). This all depends, of course, on our willingness to accept that nuclear power is a viable (and safe) source of future energy alongside wind, solar, and geothermal sources.

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  • nishi tomar

    this will be much better than any other conventional power source.It may be recognised as the milestone in the path of inventions of new energy resources.Using this we can also save our traditional energy resourcs,i.e also a major task before us.Perheps we may give this to our future generation as a gift.

  • Scot Moss

    Right now TerraPower seams to be the only viable option for our current power distribution system. Wind and solar although great options cannot generate enough consistent power in a single location to be viable for distribution.

    I also love the fact that the system uses spent waste from traditional reactors as fuel.

    This may take a few decades to implement but it looks very promising.

  • Hotrao

    I think that, despite everyone fearing the "nuclear option", this could be part of our future: A source of power non impacting at environmental level (at least in a reasonable amount of time).

    On the other side, I don't understand if this will create a problem of waste or at least of maintenance, but if benefits are obvious in the quite immediate timeframe, on the problems side we are moving the problem to future generations and this is nor fair nor smart.

    Another possible problem could arise from those having access to this technology and, more in general to nuclear activities. This could be overrun by limiting the market by regulating it very strictly.

    Overall I'm positive on this solution, while I think a set of measures should be put in place to ensure a sustainable and safe approach is guaranted.

    This post as a comment also at

  • Chris Reich

    This is, if proven safe, is the best alternative to our energy problem I've seen. I've often wondered why we didn't scale up some of the technology used to power our large nuclear fueled war ships.

    No down side is reported in this story which makes me a little suspect. The biggest structure at a "real" nuclear plant is the cooling tower. How is this reactor cooled? The other substantial structure one sees at a nuclear plant is the containment dome. So what happens if this wave becomes a Tsunami?

    I'm glad we are working on it and look forward to seeing more on this technology.

    As the other poster Scott says, better than coal. Amen to that. And if we can produce enough electricity to convert our cars to clean electrons we can say goodbye to oil too!

    Good luck TerraPower!

    Chris Reich

  • Chris Reich

    Thanks! I would seem that the building to house and secure the power plant would be much bigger than the heat producing unit. That is novel. Still we need to add a boiler and a turbine so it will end up bigger than a hit tub.

    Wouldn't this be incredibly great? And we get to use the old waste...