Huge investment is needed in energy efficiency if the UK is to cut its emissions without handing over huge areas of the countryside to wind turbines, solar panels and fuel crops, campaigners have claimed.

A report by the Campaign to Protect Rural England (CPRE) warns there is a need for much more focus on conserving energy and reducing demand as part of efforts to tackle climate change emissions, rather than just making heat and power supplies cleaner.

Even "fairly ambitious" measures to give major efficiency make-overs to 65,000 homes a year - up from around 1,000 a year at the moment - which could cut emissions by 44% from homes by 2050, would still leave a significant shortfall in meeting targets.

The UK has an overall legally-binding target to cut greenhouse gases by 80% by 2050, and meeting the target without reducing energy use further from homes would need more renewables and low-carbon power, and lead to higher bills, the report said.

One scenario in the report suggests 3,500 new wind turbines, including 800 onshore, and 8,000 hectares (20,000 acres) of new solar panels would be needed, while half of England would also need to be planted with crops that can be used to produce energy.

The report calls for a much bolder national programme to reduce energy and carbon emissions from homes and community buildings, and for the implementation of stronger zero-carbon standards for new homes.

Rural communities, which often face worse energy efficiency and higher fuel bills, particularly if they are off the gas grid, must also get a fairer share of funding for home improvements, the report urged.

Almost a fifth (18%) of the population lives in rural areas but those areas receive less than 1% of funding for energy efficiency improvements, the CPRE said.

Nick Clack, senior energy campaigner at the CPRE, said: "Our research intensifies calls for the new government to implement a much bolder national programme to reduce energy and carbon emissions from homes if we are to get anywhere near the 80% emissions cuts required under the Climate Change Act.

"Unless there is effective government support for this work, we risk seeing large areas of the countryside lost to avoidable new energy infrastructure and even higher energy bills."

He said existing national energy saving schemes had failed to sufficiently reduce energy use, and called for a focus on community-led retrofit initiatives to target fuel-poor homes and more "persuasive and understandable" cash incentives for all households.

"Such approaches would not only reduce carbon emissions, but reduce people's energy bills, create jobs and help protect our landscapes.

"Much of the focus of the current debate is on supply: on whether to frack or where to put wind turbines. If we are to close the big energy gap, we need to make huge progress on reducing our need for energy from today."

The report by the CPRE is based on research conducted for the organisation by Cambridge Architectural Research and Anglia Ruskin University.