Is there truth in Rishi Sunak’s net zero attack on Labour?

Rishi Sunak and Keir Starmer have faced off for the final time in a TV debate, trading familiar blows over immigration and tax. Sunak came armed with a new attack line over the cost of Labour’s net zero climate plans, but does it stack up?

What did Sunak say about the net zero target?

During the debate, Sunak said: “We’ve just found a recording … [from] Labour … admitting that their [climate] plans will cost hundreds of billions of pounds.”

The recording of Labour’s Darren Jones, the shadow chief secretary to the Treasury, at a public event in March 2024 had been published by the Daily Telegraph on the evening of the debate.

The article featured on the newspaper’s front page the next morning and was picked up by the Times, the Daily Mail, the Sun, the Daily Express and even the Financial Times.

Jones’s comment that the UK would need to invest “hundreds of billions” to reach net zero is not in dispute. Yet the way it was characterised by Sunak was hugely misleading.

It is an example of the “scary-sounding numbers” that Sunak, along with newspapers and other Conservative politicians, has used to mislead voters about the “cost” of net zero.

Will Labour’s plans really cost ‘hundreds of billions of pounds’?

Sunak’s statement is misleading on several levels.

While the government’s advisory Climate Change Committee (CCC) has estimated net investment needs of £321bn for the UK to reach net zero by 2050, it was a Conservative government that put this target into law in 2019. The Conservative election manifesto continues to back the 2050 target.

As such, it was a bit rich for Sunak to describe the 2050 target as Labour’s plan.

Which climate costs and benefits did Sunak leave out?

Sunak next misled viewers by omitting the wider economic benefits that would be delivered by taking action on climate change.

Although these benefits were not estimated by the CCC, a 2023 report for industry group Energy UK found that an accelerated shift towards net zero “could boost the UK’s economy by £240bn in 2050 more than current trajectories”. It said this accelerated shift could increase GDP in every part of the country, by between 5.4-7.5% in 2050 compared with the UK’s current path.

Equally importantly, Sunak also omitted the costs of inaction on climate change, including the impacts of increasingly frequent extremes and of continued exposure to volatile fossil fuel prices.

In 2021, while Sunak was chancellor, the Treasury published a report concluding: “The costs of global [climate] inaction significantly outweigh the costs of action.”

And the Office for Budget Responsibility (OBR) concluded in 2023 that continuing to rely on gas could be more than twice as costly for the public finances as investing in net zero.

Will Labour’s 2030 clean power target cost an ‘extra £116bn’?

Sunak’s energy secretary, Claire Coutinho, has also been using scary-sounding numbers to attack Labour’s climate plans.

Earlier this week, she tweeted that Labour’s target for clean power by 2030 “would need an extra £116bn of investment”. This characterisation is false.

Coutinho is relying on analysis from Aurora Energy Research, which found that the Conservative target of clean power by 2035 would need investment of £105bn during 2025-2035, compared with £116bn over the same period to hit Labour’s 2030 goal. The “extra” investment is only £11bn.

Moreover, Aurora found that household energy bills would be lower under Labour’s target.

What are the three key tactics used to mislead on net zero?

The net zero claims made by Sunak and Coutinho neatly illustrate the three key tactics used to mislead about the “costs” of climate action.

Specifically, these are: ignoring the costs of business as usual, highlighting costs but ignoring benefits, and ignoring the costs of inaction on climate change.

These tactics start to crumble when faced with a simple question posed by the former US climate chief Todd Stern: “Compared to what?”

When the climate-sceptic columnist Ross Clark wrote in the Sun over the weekend: “National Grid ESO … estimated decarbonising Britain’s entire energy system will cost between £2.8tn and £3tn,” he did not consider Stern’s question, even though a high-carbon energy system would not be free.

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If he had asked the question, then Clark would have been forced to admit that a business-as-usual scenario that did not reach net zero would “incur broadly the same costs”, according to National Grid ESO. The obvious conclusion from this analysis is the exact opposite of what Clark implies.

So do Sunak’s net zero claims stack up?

No. Sunak says he supports net zero by 2050, but implies that only Labour’s plans for getting there would cost “hundreds of billions”, as though his own route could be cost-free.

Yet the evidence suggests that the UK investing hundreds of billions of pounds to reach net zero would be money well spent. Compared with what? The wider economic benefits of taking action – and the avoided cost of climate inaction.