Nuclear power drive obsesses over baseload: Do we need it?

Lately there has been a mounting noise on behalf of more nuclear power in
Scotland, pleas for John Swinney to do a u-turn on his ruling out of new
nuclear reactors.

Calls for Scotland to embrace nuclear have been greeted
with a certain amount of enthusiasm in some quarters, including many SNP
voters. But what troubles me, in the current debate, is that all too often
it feels like we are stuck in an old vision of the grid – and one of the
terms that suggests this is ‘baseload’.

Baseload is defined as the
minimum amount of electricity required by a grid to meet the continuous
demand for power over a day. Currently, it’s mostly used to refer to the
generating capacity that we need to always be there if the wind stops and
the sun doesn’t shine. Britain Remade, for instance, talks about nuclear
in terms of “clean, reliable baseload power”.

But what if nuclear is actually a technology that does not suit a modern renewable grid? What if wind and nuclear are not good bedfellows and, as a baseload, new plants
will only make our electricity more expensive?

In a recent Substack, David Toke, author of Energy Revolutions: Profiteering versus Democracy, described the “accepted truth” in the media that new nuclear power is
needed because there is no other practical or cheaper way to balance
fluctuating wind and solar power, as “demonstrably false”.

He said it
“runs counter to the way that the UK electricity grid is going to be
balanced anyway” – which, he noted, is by gas engines and turbines
“that are hardly ever used”. Simple gas fired power plants, he said,
are many times cheaper per MW compared to nuclear power plant.

Toke advocated for a system balanced by more batteries and other storage as well
as gas turbines or engines which will proved “capacity” rather than
generate much energy. He has a strong point. Of course, the problem with
gas, is that it is, famously, a fossil fuel and produces greenhouse gas
emissions.

However, if, as Toke says, that gas is an increasingly small
percentage of electricity generation, about handling the moments when
demand is not met by wind and solar, the 5% predicted by the UK
Government’s Clean Power 2030 Action Plan, to be what we require, perhaps
that’s no big deal. It’s a bigger deal, though, if the gas power
station emissions required to balance the grid are, as another Substack
write calculated recently more like 19 percent.

Interestingly, Toke, whose
main criticisms of nuclear are its high cost of electricity generation and
lack of grid balancing flexibility, also noted that if we are thinking
about the financial costs of reducing emissions we might be better off
spending our money in other ways. For instance: “setting up a scheme to
pay £15000 each to 500,000 residents not on the gas grid to switch to heat
pumps will likely save as much carbon as Sizewell C is likely to
save”.

But it seems to me the question is not whether nuclear power is
simply right or wrong, but what its place is within the kind of modern grid
we are developing, a grid which faces transmission challenges between
Scotland, already producing more energy than it uses, and elsewhere, and
whether the costs are worth it. Too often those that argue for nuclear sell
it via the concept ‘baseload’.

But you only have to do a quick scan of
the internet to see it is brimming also with articles about how baseload is
extinct or outdated. These critics point out that what the grid actually
needs is more flexible sources, both of storage and power. One of the
problems is that traditional nuclear power stations tend to be all on or
all off. Torness, for instance, has either one or both of its reactors,
either at full or zero capacity.

That kind of inflexibility in nuclear
plants has already led to constraint payments being made to wind farms,
which have been switched off because there was too little demand even as
the nuclear power stations kept producing. In 2020 energy consultants
Cornwall Insight estimated the quantity in MWh of constraints that could
have been avoided had nuclear power plants in Scotland been shut during two
recent years. It found that, in 2017, 94 per cent worth of windfarm output
that had been turned off (constrained) could have been generated had
nuclear power plant not been operating.

Herald 29th July 2025, https://www.heraldscotland.com/opinion/25350226.nuclear-power-drive-obsesses-baseload-need/