“[It's like taking] the entire nuclear infrastructure and collapsing it into one vessel.”
— TerraPower’s John Gilleland at an April 2009 presentation at UC Berkeley

Can nuclear power be considered green?

Greentech Media has been on the forefront of covering nuclear power as a potential clean energy source for several years now.  We have taken detailed looks at small modular reactors (SMRs) and even looked at some activity in fusion science (including SMRs from NuScale and Hyperion, fusion from General Fusion and TriAlpha, nuclear waste disposal from Kurion, Small Modular Reactor report here).

It's always a contentious issue. 

Yes, nuclear power is carbon-free in operation -- but uranium extraction and plant construction can hardly be considered carbon neutral.  And yes, it's baseload power with a low price per kilowatt hour, but it's very expensive to build and harrowingly difficult to finance. 

And then there are the huge and vexing issues of safety and proliferation.

But TerraPower's wildly unorthodox reactor design actually can consume used nuclear fuel as its power source.  And the firm has just raised a $35 million financing round.

Bill Gates, Massachusetts-based VC firm Charles River Ventures and Khosla Ventures joined in the Round B, according to a Reuters article.

It's an absolutely audacious VC bet and the entrepreneurs and investors involved deserve credit for sheer (I don't know if I can say this in a family publication) brass balls, given the staggering technical, regulatory and temporal risks involved.

Background on the TerraPower idea

TerraPower was spun out of Intellectual Ventures (the think-tank created by ex-Microsoft chief scientist Nathan Myhrvold) to develop nuclear reactors that run primarily on depleted uranium. Blll Gates is an active funder and participant in the firm and, based on comments from the CEO, money is not an obstacle.

Switching from enriched fuel to DU reduces risks associated with nuclear proliferation and transportation as well as the amount of nuclear waste. TerraPower’s reactor does, however, need fissile material (i.e., enriched uranium) to initiate a reaction.

TerraPower has at least 20 employees and is run by John Gilleland, a big name in the reactor physics field and the manager of the nuclear program at Intellectual Ventures. Before Terrapower, he was the CEO of Archimedes Technology Group, where he focused on new technologies for mitigating waste from nuclear weapons, reprocessing spent reactor fuel and enriching uranium. Before that, he was at Bechtel and was the managing director at the International Thermonuclear Experimental Reactor program. In 16 years at General Atomics, he headed the construction of an advanced fusion research test bed.

In an April 2009 presentation in Berkeley, Calif., Gilleland described the TerraWave Traveling Wave Reactor (TWR) as embodying a “self-sustaining deflagration of breeding and burning,” with “waves of breeding and burning propagating through fertile material indefinitely.”  The presentation also claims that a “core life of 60 years is practical.” 

The firm has hired an all-star team of nuclear engineers to design this revolutionary type of reactor.

In a recently published paper co-authored by Myhrvold, representatives of LLNL, and the Hoover Institute entitled “Nuclear fission power for 21st century needs: Enabling technologies for large-scale, low-risk, affordable nuclear electricity,” the team proposes a "[r]epresentative system-level integration that obviates all fuel supply issues, including the entire set of isotopic enrichment ones, while rendering comparably useful as nuclear fuels all of the actinide elements and isotopes. It entirely avoids transport and reprocessing and the full set of ad hoc waste disposal issues, and completely precludes all those involving proliferation/diversion of fissile isotopes into weapons programs. It provides zero biospheric hazard in the event of either natural or man-made catastrophe. It requires -- indeed, admits of -- no operator control actions, other than initial start-up and final shutdown commands, so that operator errors are entirely precluded; during the half-century of potentially full-power operational life in between these two commands, it thermostatically regulates in an entirely automatic manner its own nuclear power generation to match the heat removed from its core in a time-varying fashion."

The team concludes: "We therefore project a bright future for cheap electricity safely obtained in >10 TWe quantities from nuclear power reactors of this new type, moreover over multi-century time frames."

TerraPower has stated that commercial deployment can begin in less than 15 years.

The firm is considering modular 100 MWe and 300 MWe sizes as well as 1 GWe units.

Regulatory quicksand and long time frames

Introducing a small modular reactor like the NuScale design, a new reactor that still bears a great resemblance to existing light water reactors, is a challenge to the testing and approval process of the Nuclear Regulatory Commission.  It takes years and years from the date of submission of plans to approval and eventual site permitting and construction.

Introducing a new reactor design like TerraPower, one that operates on radically different physical principles than that of a light water reactor, is a proposition that is saddled with profound marketplace and regulatory challenges. 

It is unlikely that some of the investors will live to see the plant actually switched on and operating.  It would seem that the time frame would require a different type of VC fund lifetime instead of the typical eight to ten years.  Clearly, Khosla and Gates want to partner with or license the technology to Toshiba or Areva or Babcock & Wilcox.

Nuclear remains a financial and safety challenge, and nuclear's detractors make good arguments -- everyone from Amory Lovins and his Rocky Mountain Institute to NIRS, the Nuclear Information and Resource Service, are able to point out the cost overruns and safety concerns (more valid objections can be found here).

About 20 percent of U.S. electricity comes from nuclear sources.  Other nations like China, India and France will rely on nuclear for baseload power to an even greater degree going forward.  We can't just wish it away.

TerraPower will look to partner with firms and nations other than the U.S. where nuclear is less stigmatized -- perhaps Russia, China, India or France.

In any case, kudos to the entrepreneurs involved for thinking way outside of the box -- and to the investors who are putting their money where their mouth is.