A study by the Green Alliance has argued that Britain's failure to truly focus on energy-efficiency measures is damaging public health and wasting millions of pounds.

It says that the country's existing strategy focuses too much on energy supply whilst largely ignoring opportunities and measures to cut energy consumption.

The study concluded that the NHS could save £3.7 billion every year if a new approach were taken to better target inefficient homes and to take polluting vehicles off the roads.

The report was written with Centre for Research into Energy Demand Solutions (CREDS). It argued that if the UK's decarbonisation strategy could focus on reducing energy demand, it would help to improve public spaces and homes, create cleaner air and speed up the move towards a net-zero economy.

By switching 1.7% of car journeys to walking or cycling alternatives, the UK could save £2.5 billion annually, which equates to 2% of the NHS's overall budget. This would happen by reducing lifestyle health problems such as diabetes and heart disease.

Equally, moving to green transport could avoid 65,000 early deaths every year from air pollution. By upping energy-efficiency measures indoors, another £1.2 billion annually would be saved through fewer heart attacks and cases of pneumonia and high blood pressure.

The report was welcomed by the energy industry, with the UK Health Alliance on Climate Change saying that it demonstrated how small tweaks to energy use could have significant benefits on the environment, economy and public health.

CREDS is a collaboration of researchers across 15 of the UK's leading universities. It lobbies the government to take action against climate change by reducing energy demand overall, improving energy-efficiency through technology and by better aligning supply and demand with use of tariffs and other supply techniques.