Onshore wind and solar power farms in Northumberland could fuel millions of homes, according to new research.

Estimates from the National Grid suggest the UK must double the amount of renewable electricity it produces over the next six years to replace energy phased out from fossil fuels.

Climate and energy charity Friends of the Earth has called on all political parties to pledge to lift restrictions on onshore wind farms.

The campaign group urged local authorities to identify suitable renewable energy sites in local plans, and called for further investment in the electricity grid as a "top infrastructure priority".

Research conducted by Exeter University's Environmental Intelligence Centre and Friends of the Earth shows there are around 126 square kilometres of land in Northumberland suitable for onshore wind farms.

There are approximately 172 square kilometres capable of hosting solar power sites.

This would generate a total of 13,077 gigawatt-hours (GWh) of electricity, which would power around 4,843,300 homes based on average electricity consumption.

A Department for Energy Security and Net Zero spokesperson said: "Onshore wind power capacity has almost quadrupled since 2010 and renewables account for nearly half of our electricity, up from just 7 per cent.

"We’ve also streamlined planning rules in England to make it easier for councils to identify suitable land for onshore wind."