Weakening the UK’s net zero policy would disrupt business and damage the economy, the UK’s chief climate adviser has warned.

Nigel Topping, chair of the Climate Change Committee (CCC), said: “The U-turns are really damaging to inward investor confidence. If we really want to grow the economy, then investing and getting good at building stuff is essential.”

His intervention comes as the CCC published its latest report to parliament on Wednesday, on progress towards the target of net zero greenhouse gas emissions by 2050. The report found that although the push towards renewable energy has gone well, and more people are switching to electric cars, the take-up of heat pumps has lagged behind severely.

Topping pointed to a recent CBI report finding the net zero economy was worth about £100bn a year to the UK, growing faster than the rest of the economy and producing higher paid jobs. “We’ve got the institutional infrastructure in place since the [2008] Climate Change Act, and real consistency of direction and progress, and we know that consistency is super important for industry in making investment decisions,” he said.

In the wake of Keir Starmer’s resignation, the stance of his likely successor, Andy Burnham, on green issues has come under renewed scrutiny. Burnham has previously supported offshore wind and renewable energy, but some of his advisers have appeared to contrast his bid for “reindustrialisation” with the push for net zero, despite evidence from economists that the two are complementary, rather than opposed.

Topping made it clear that any attempt to water down the UK’s push for a clean economy would deter businesses and investors, and add to the cost of living by increasing reliance on fossil fuels. “The power system decarbonisation is largely done,” he said. “All that work’s been done, that’s something we should celebrate as a country. It’s not just an achievement, but something that’s been achieved beyond politics.”

The next prime minister must “hold the course”, and move faster towards renewable energy, electric vehicles and heat pumps, which when used correctly are cheaper than their fossil fuel counterparts. “That’s where the real benefits come – [you can] really unlock a lot of savings,” said Topping.

The report raised concerns over the take-up of heat pumps: although they are at least three times more efficient than gas boilers, they carry a heavy upfront price tag. And for consumers on some energy tariffs they do not produce savings on bills, because in the UK electricity is made more expensive than gas by the way the power market is structured. Installations in existing homes went up just 7% this year compared with 56% the year before, the CCC said.

And yet the report found heat pumps produce the greatest savings – of about £1,200 a year on energy bills for urban dwellers, and £1,900 a year for rural homes dependent on oil heating – when they are used alongside solar panels and EVs. These changes, however, are generally only within reach of better-off households.

Some heat pumps can also double as air conditioners, interest in which has soared as the second record heatwave of the year has led to widespread disruption, health warnings, and closed schools.

Topping called on government to break the link between power prices and the cost of gas, which would reflect the true lower cost of electricity from renewable generation and make heat pumps more attractive to households. He also called for lower income households to be helped to decarbonise, and warned against disinformation that was misleading people on the benefits of heat pumps.

Jess Ralston, head of energy at the Energy and Climate Intelligence Unit, said high fossil fuel prices were encouraging people to switch to cleaner options. “We’re seeing a surge of interest from the British public in net zero technologies like solar panels, EVs and home batteries,” she said. “But even though interest is growing and numbers are on the up, the UK is currently a long way behind countries like Germany and France in switching to heat pumps.”