by: Don Jones, retired nuclear industry engineer, 2020 Sept.14
There are opposing views on whether nuclear and non-hydro renewable energy – variable intermittent renewable energy (VIRE) like wind and solar – can coexist on an electricity grid.
We have this now typical view from Duke Energy (Ref.1), “More importantly, Duke Energy’s plan follows an emerging trend that acknowledges a clean energy economy is only possible with all carbon-free technologies working together. As more companies and policymakers look for solutions to our climate challenges, we must create a pathway to ensure nuclear, wind, solar and other carbon-free technologies successfully exist together.”
Duke’s statement contradicts the view expressed in the oft quoted, , “If someone declares publicly that nuclear power would be needed in the baseload because of fluctuating energy from wind or sun in the grid, he has either not understood how an electricity grid or a nuclear plant operates, or he consciously lies to the public. Nuclear energy and renewable energies cannot be combined “– Siegmer Gabriel (former Federal Environment Minister of Germany).
Can they coexist? Not at present time, not without help from gas, coal or hydro to provide the load-following capability.
In Ontario VIRE does not have priority over nuclear. Available VIRE is manoeuvred before nuclear is manoeuvred and if necessary curtailed completely. Presently the CANDU reactors on the Ontario grid do not load-follow (Ref. 2) so to maintain grid stability course power adjustments are made by bypassing steam on one or more of the eight CANDU units of Bruce Power (load-cycling) and more frequent power adjustments (load-following) are made by the hydro generators and/or the combined cycle gas turbine (CCGT) units. Even without VIRE it would not be possible to have a stable Ontario grid without the load-following and frequency control capability provided by the hydro and/or gas generators.
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