Pebble Bed Advanced High Temperature Reactor at UC Berkeley — low cost nuclear?

Per Peterson

Per Peterson’s aim is to develop really compact nuclear units with very high power densities, based on mostly well-understood technology that is deployable on the time-scale of a decade or less. The driving aim is to get these units commercialised in the near term, and to bring down costs, thereby paving the way for later widespread commercial deployment of full Generation IV designs like the LFTR and IFR, which not only achieve high burnup, but also completely close the fuel cycle.

Barry Brook and Tom Blees were invited to visit Per Peterson’s laboratory at the Nuclear Engineering Department of UC Berkeley. I would love to have been there, sigh. Anyhow, read Barry’s account, almost as good as being there.

When I visited California earlier this month, Tom Blees and I paid a visit to Prof Per Peterson and Prof Jasmina Vujic at the Nuclear Engineering Department of UC Berkeley. After chatting over lunch, Per took us on a personal tour of his lab, which was quite an experience. Per’s research focuses on development of a high-temperature reactor with an incredibly high power density. Why? In short, it’s about the money. Per’s argument — and a quite persasive one — is that if the costs of advanced reactors can be brought way down, below that of pressurised and boiling water reactors (PWRs and BWRs), then their scaled-up deployment is highly likely. The following post owes a lot to Per’s insights on this critical issue.


You’ll be rewarded for reading Barry’s complete post. Also, Per Peterson’s homepage for the PB-AHTR research is here.

How does the UCB reactor design stack up relative to current and other advanced reactor concepts (e.g., LFTR, S-PRISM)? At the 2007 MIT-Stanford Workshop on Nuclear Fission: Opportunities for Fundamental Research and Breakthrough in Fission, one of the papers by UC Berkeley’s Ehud Greenspan compares four advanced reactor classes, one of which is the PB-AHTR (class 2). Download and archive this Ehud Greenspan presentation — it is almost an encyclopedia of nuclear fuel and reactor systems, including high-performance transportation fuel production:

  1. Light-water cooled breeding reactors
  2. Liquid-salt cooled high temperature thermal reactors
  3. Nuclear battery type reactors
  4. Deployment of fast reactors without separating TRU from LWR spent fuel

We obviously will not know for sure until we have built PB-AHTR’s at commercial scale, but at least one study by ORNL indicate the capital cost should be about 70% of current LWR reactors (e.g., the Westinghouse AP-1000). BTW, Greenspan lists just one “Con” for the AHTR class, “not sustainable”. I need to read more on this, as I thought the design was sustainable (i.e., does not require mining new fissionable feedstock).