by James C. Sherlock
A reader asked two excellent questions:
The issues with nuclear power have been:
1. The waste generated remains radioactive and dangerous for a very long time.
2. In the case of failure, a huge risk is exposed as was the case in Three Mile Island, Chernobyl and Fukishima.
Do these new, small reactors bypass either of those risks?
The short answers are:
- The new large reactors for sale now are safer than those in the field.
- New small reactors offer to greatly improve both the safety and efficiency of even the latest versions of the large reactors with a vastly smaller footprint. That includes Westinghouse’s new small reactor announced today that uses technology already approved by the Nuclear Regulatory Commission (NRC). It expects deployment in 2027.
- The designs of the small modular reactors (SMRs) in development under dual Department of Energy (DOE) and corporate sponsorship incorporate more revolutionary safety design features than any the designs already approved by the NRC for operational use. You will read below that the DOE has identified three revolutionary commercial vendor-backed SMR designs that it expects to be ready for NRC operating approval by 2030.
- Some of the new SMRs actually consume nuclear waste from other sources.
Now for the longer version.
First, motivation. Nuclear plants produce energy without carbon emissions — a huge legacy advantage that also addresses climate alarm.
Every generation of nuclear power brings improvements to address safety, waste and cost competitiveness both among nuclear vendors and with other sources of power.
It is dedicated and well-funded work, not only for the public benefit, but by companies trying to keep nuclear power competitive in the market and make a profit in power and heat generation worldwide.
To do that, every improvement they make is progress to answer the two questions posed, and the third, which is cost.
Absent war, commercial viability and profit form the most reliable basis for innovation. They do here.
Currently operational technology. Only Pressurized Water Reactors (PWRs) (62) and Boiling Water Reactors (BWRs) (31) are in commercial operation in the United States.
The four reactors in commercial operation in Virginia are Westinghouse 3-loop PWRs.
Westinghouse’s current flagship AP1000 reactor and the new small AP300 are advanced PWR technology.
Dominion in 2014 chose GE Hitachi Nuclear Energy’s Economic Simplified Boiling-Water Reactor (ESBWR) nuclear technology for the third reactor at Lake Anna if they ever build it. ESBWR includes
passive gravity-based safety features – water stored above the reactor that would flow to the reactor by gravity in the unlikely event of a significant nuclear accident and circulate naturally to maintain cooling of the nuclear fuel.
That design directly (and presciently since it was designed before Fukushima) addresses the cause of the Fukushima disaster.
Industry-wide efforts. For industry-wide safety improvements in development, see Accident Tolerant Fuel (ATF) and Advanced Manufacturing Technologies (AMTs). See who is doing that work at the same link.
Gen IV. Gen IV nuclear technologies are competing with one another under different corporate sponsorships.
For the leaders, see the federal Department of Energy’s 3 Advanced Reactor Systems to watch by 2030. It is short, easy reading and very informative.
The three are the Sodium-Cooled Fast Reactor (SCR) the Very High Temperature Reactor (VHTR) and the Molten Salt Reactor (MSR). The individual links provide more detail on each design.
All three are safer than current designs and minimize waste. Two of them can consume spent fuel from other reactors. All of them offer to be far less expensive per KwH than current generation systems.
Fukushima. For want of a nail…
The Fukushima Daiichi Nuclear Power Plant disaster was a result not of the earthquake itself — emergency shutdown occurred as designed — but rather the tsunami flooding of some of the diesel generators that maintained coolant water flow to the reactors.
Long story short, the three diesel generators at Daiichi that were in water-tight buildings worked. The others flooded.
Nearby Fukushima Daini Nuclear Power Plant was also struck by the tsunami. All of the diesel generators were in flood-proof buildings. They worked fine, and Daini was back online in hours.
Investigations determined, among other things, that if the flooded switching stations at Daiichi had been in flood-proof locations,
power would have been provided by these generators to the reactors’ cooling systems and thus the catastrophe would have been averted.
- regulatory capture by the provider of its government regulator had resulted in lax inspections; and
- the original GE plant design for the locations of the diesel generators was faulty. It put them in a basement. (We are pretty much assured that nowhere in the world is a diesel generator for a nuclear cooling system located anywhere that is not flood proof.)
Bottom line. My answers to the very good questions posed by the reader are:
- Nuclear power is absolutely essential to a carbon free energy future.
- The national labs help, but improvements have both societal and capitalist motivations. It is reassuring that the investments are at least as important to the vendors (and buyers like Dow Chemical) as they are they are to the public;
- the technology of nuclear power continues to drive toward both safety and the consumption of spent nuclear fuel;
- the operators of nuclear facilities, at least until the technology makes them safe in the very worst case, must maintain a cult-like focus on safety. Because the procedures are endlessly repetitive and boring, and thus can lead to distraction. But failure is not an option for those standing beside the reactors. The threat keeps them attentive, and their every action is recorded on video. Fukushima was not caused by operator error;
- their regulators must be watched for any indication of insufficient dedication and/or capture by the industry. U.S. regulators at the FRC have shown no signs of capture of which I am aware. If there was an attempt at capture, it would likely be reported because the work itself must be nearly perfect to remain viable, much less profitable, and the vendors compete with one another; and
- With all of that, no system designed and run by humans can be perfect. Technical improvements are targeted to take human frailty out of the equation as much as possible.