The report by the National Energy System Operator (Neso) outlines several possible futures for the UK's energy transition and attempts, for the first time, to quantify the investment required to cut emissions in line with climate science. Its findings have been seized upon across the political spectrum — with critics claiming households could save £500 a year if the UK slowed its climate ambition.
But a closer look reveals a far more nuanced picture.
The price of net zero — and the cost of doing nothing
Neso's modelling suggests the UK already invests about 10% of GDP in net zero–related infrastructure. These costs will rise throughout the 2020s as the country builds new renewable power, upgrades electricity grids, expands electric vehicle use, and replaces gas boilers.
Under the most ambitious scenario:
-
Annual investment peaks at £460 billion in 2029
-
Costs then decline steadily to around 5% of GDP by 2050
-
When carbon pollution costs are included, the greenest pathway becomes the cheapest overall, saving £36 billion a year compared with a slower transition
By contrast, the "falling behind" scenario — which delays climate action and misses the 2050 target — appears cheaper in headline terms, but only because it ignores the escalating economic damage of climate change.
Does this mean higher household energy bills?
Not automatically.
The widely circulated claim that families could "save £500 a year" comes from scenarios that:
In reality, how much households pay will depend on political choices — not simply the upfront numbers in the models.
Why bills won't mirror the investment spike
-
Many costs aren't part of energy bills
Replacing petrol cars with EVs or installing heat pumps is not billed through monthly energy payments.
-
Government can spread payments over decades
For example: the Sizewell C nuclear project may cost £38bn but will be repaid over a 60-year lifespan.
-
Clean energy cuts exposure to volatile fossil fuel markets
The UK's biggest price shocks in 2021–22 came from gas markets — not climate policy.
Even so, Neso warns that high levels of investment bring a real risk of upward pressure on household bills unless government ensures costs are shared fairly.
Why slowing climate action doesn't actually save money
The argument that the UK could save £14bn per year by abandoning its legally binding 2050 target rests on one assumption: that the spiralling cost of climate damage simply doesn't count.
Neso stresses the opposite:
-
Ignoring carbon costs only delays — not removes — the bill
-
Fossil fuel dependence exposes the UK to repeated price shocks
-
Delaying clean energy also forfeits major non-financial benefits, including
As the report bluntly puts it:
"It would be wrong to interpret a delay in this cost as implying the cost is avoided entirely."
Can the report be trusted?
Yes — with caveats.
Neso's scenarios are widely used by policymakers, but the report acknowledges limitations:
-
Models are not fully optimised to minimise cost
-
Outcomes depend heavily on market variables — fuel prices, tech costs, regulatory decisions
-
The real world will not follow any single scenario exactly
In other words, the uncertainty lies not in whether net zero is beneficial, but in how efficiently the UK delivers it.
What does the government say?
Ministers welcomed the report's emphasis on long-term savings but rejected the idea that the scenarios represent actual net zero costs.
A spokesperson said:
"We fundamentally reject the idea that these illustrative scenarios reflect the real cost of moving to clean energy… Driving for clean energy saves money by reducing our exposure to fossil fuel markets."
Is accelerating the transition still worth it? Scientists say yes.
Climate experts argue the case for rapid action has only strengthened.
Greenpeace's Mel Evans said the report highlights the "clear and positive impacts of Britain standing firm" on clean energy:
He added that the cost of not acting is already enormous:
"Damage from the climate crisis has cost £13 million an hour globally for the past 20 years."