Could Small Modular Nuclear Reactors add supply-side grid flexibility?

It would make sense in the UK for SMRs to be load
following only if there were vast numbers of SMRs deployed,

13 Nov, 2025 By Tom Pashby New Civil Engineer

Small modular reactors (SMRs) could have the capability of providing the British electricity grid with flexible supplies, the government has said.

Supply-side grid flexibility is the ability of electricity sources to
adjust their output to match fluctuations in power demand in real-time. The
statement came in response to a question from an MP about whether SMRs
could be used as “load-following energy sources”.

Liberal Democrat spokesperson for energy security and net zero Pippa Heylings MP asked what assessment the Department for Energy Security and Net Zero (DESNZ) “has made of the potential merits of small modular reactors being made as load-following energy sources”.

Responding, DESNZ minister of state
Michael Shanks said: “The next generation of nuclear, including SMRs,
offers new possibilities, including faster deployment, lower capital costs
and greater flexibility. “Whilst nuclear energy has a unique role to play
in delivering stable, low-carbon baseload energy, SMRs may be able to serve the electricity grid more flexibly than traditional nuclear, as well as
unlock a range of additional applications in energy sectors beyond grid
electricity.”

It would only make sense in the UK for SMRs to be load
following if there were vast numbers of SMRs deployed, representing a
significant proportion of the electricity generation capacity on the
national electricity transmission system of Great Britain, for them to be
load-following.

University of Sussex professor of science and technology
policy Andy Stirling told NCE: “This parliamentary answer repeats a
longstanding malaise in UK energy policy. “For far too long,
eccentrically strong official nuclear attachments have been dominated by
reference to claimed ‘new possibilities’, to what nuclear ‘may be
able’ to do, and to an unsubstantiated ‘unique role’. “

Whichever side of these debates one is on, it is clear that what is needed most is what used to be routine – but has been lacking for more than a decade.
“Questions over cost, security or flexibility claims can only be settled
by detailed comparative analysis that includes balanced attention to
non-nuclear strategies as well as nuclear ‘possibilities’. “

When such a picture is looked at in a fair way, current trends are making it
impossible even for formerly nuclear-enthusiastic bodies (like the Royal
Society) to conclude – even when looking at UK Government data –
anything other than that there is no rational need for any nuclear
contribution.”

New Civil Engineer 13th Nov 2025,
https://www.newcivilengineer.com/latest/could-smrs-add-supply-side-grid-flexibility-13-11-2025/