Nuclear generation is sometimes misunderstood as “only baseload capable” and therefore incompatible with wind and solar because of their erratic generation profiles. This is not true. It is true that if there is a large baseload demand, then the economics favor nuclear plants that are optimized to run 24/7/365. Like any productive asset with high capital cost, the owner prefers high utilization to earn the highest return on that investment. This is one of the essential reasons that wind and solar will always be expensive – every hour they are not generating at rated capacity their high capital investment is not earning a return.
The engineering design of nuclear plants covers a range of load-response capabilities: from very fast response (think nuclear submarines and warships) to pure-baseload. The electric power market has mostly been characterized by baseload customers so traditional plant designs have been optimized for those economics. That said, even old 1960s designs like the French and German fleets are operated in load following mode. Here’s the power output time series of Golftech 2, one of the load following French nuclear plants.
The French electrical grid is sometimes 90%+ nuclear, so obviously nuclear generation has to maneuver to match the real-world demand (there is no magical “demand management” which makes the problem of the intermittency of wind/solar go away, this is the real-world of near zero carbon electricity in 2015). More references on nuclear load-following:
IAEA Technical Meeting – Load Following Sept 4-6 2013, Paris (source of the Golfech 2 chart, considerable details on how EDF plants are operated for load following)
So far we’ve only discussed the 1970s technology – designed and built when the primary market was for pure baseload generation. Tomorrow’s generation market will need to incorporate “renewables” which generate if the sun and weather dictate. For the zero carbon carbon future we can balance the intermittent renewables with storage or nuclear. If everyone is as wealthy as Bill Gates we could use storage. Otherwise we need dispatchable nuclear plants that can respond with high ramp-rates to VRE (variable renewable energy). Many of the advanced Gen IV reactors have economic load-following capability inherent in their designs.
The first to be deployed SMR load-follower is likely to be NuScale’s design, a creative way to achieve variable output with tried and true LWR technology:
Yes. NuScale’s SMR technology includes unique capabilities for following electric load requirements as they vary with customer demand and rapid changes experienced with renewable generation sources.
There are three means to change power output from a NuScale facility:
Dispatchable modules – taking one or more reactors offline over a period of days
Power Maneuverability – adjusting reactor power over a period of minutes/hours
Turbine Bypass – bypassing turbine steam to the condenser over a period of seconds/minutes/hours
NuScale power is working with industry leaders and potential customers to ensure that these capabilities provide the flexibility required by the evolving electric grid. This capability, called NuFollowTM, is unique to NuScale and holds the promise of expanding the deployment of renewables without backup from fossil-fired generating sources, such as natural gas-fired, combined cycle gas turbines (CCGTs)