A new report has been published showing that if the UK is to secure enough low-cost power capacity to meet our carbon targets, new onshore wind turbines will be needed to replace older wind farms.

The report by RenewableUK warns that more than eight gigawatts (GW) of onshore wind – which currently generates nearly a fifth (17.5 percent) of the UK’s entire renewable power output – could be retired over the next two decades. New policies are needed to support replacing, or ‘repowering’, these older onshore wind farms.

The UK’s first commercial wind farms were developed in the 1990s and were built to operate for 20-25 years. The new report, “Onshore Wind: The UK’s Next Generation” sets out the case for building new projects with more powerful turbines on existing wind farm sites. Replacing older turbines with more efficient models means that fewer turbines would be installed than are currently operating at each site. The report also advocates other options such as upgrading turbines which are already operating, or allowing existing projects to generate for longer than originally envisaged.

The UK already faces a low-carbon electricity generation gap of up to 18 percent of the country’s current total electricity demand by 2030, according to the Government’s advisory body the Committee on Climate Change (CCC).

RenewableUK’s report warns that if the Government fails to support repowering onshore wind sites, this gap could grow as 8.27GW of onshore wind capacity – enough to meet the power needs of over 5m homes a year – reaches its 25-year expected lifespan.

The warning from industry follows the revelation earlier this month of Government figures showing the UK falling further behind on meeting carbon targets. The CCC is also expected to publish advice next month to tighten the UK’s carbon reduction targets further, in line with limiting global warming to 1.5 degrees.

Under the report’s ‘optimum scenario’, 12GW of replacement onshore wind capacity could be installed, which would help us to fill the energy gap by powering nearly 8m homes a year and contribute to climate targets. That scenario envisages more applications for repowering being approved and more powerful turbines installed. Under the ‘low scenario’, however, just 2.76GW of new capacity would be installed – a net loss of 5.5GW – due to fewer successful planning applications and smaller turbines being used.

RenewableUK’s deputy chief executive Emma Pinchbeck said: “This should be an easy win on climate change that cuts emissions and secures cheap power for consumers.

"The public mood is for more urgent action to tackle climate change and this is a concrete example of where Government can act to avoid backsliding on progress against our carbon reduction targets. We need to see positive policies in place that will keep Britain powered up with clean, affordable electricity”.