Back-stopping renewables: the nuclear option?

Nuclear power can backstop much volatility in renewable-heavy grids, for costs of 15-25c/kWh. This is at least 70% less costly than large batteries or green hydrogen, but could see less wind and solar developed overall. This 13-page note reviews nuclear flexibility and sees nuclear growth accelerating.


Four types of volatility in renewable-heavy grids are described on page 2 and will require a back-up.

There are limitations for batteries in hydrogen, in smoothing this volatility, as discussed on pages 3-4.

What about nuclear? An improving economic rationale is noted on pages 5-6, prompting us to re-visit the possibility of flexible nuclear plant operation.

Technical issues for manoeuvring large nuclear power plants, scaling their output up and down, are laid out from first principles on pages 7-11, including minute-by-minute ramp-rates and the largest challenge, which is cold-starts.

The economics of nuclear flexibility are calculated on page 12, showing costs around 15-25c/kWh for a new Western greenfield facility, which is less than large batteries and hydrogen.

Our conclusions – and who benefits – are summarized on page 13.