Engineers have claimed that schools and hospitals in the UK could be powered by tapping heat from under the ground, saving taxpayers thousands of pounds every year.
According to a report in the Telegraph, engineers told a Royal Academy of Engineering conference on the potential use of geothermal energy that the UK is sitting on a "vast resource of untapped energy".
By using ground source heat pumps, the energy can be transferred from hundreds of feet below the ground to the central heating system, while the same pump can also cool the building by taking heat out of the air in the summer.
The technology is widely used in Scandinavia and the US but has failed to take off in the UK because of the cost and the availability of cheap oil and gas.
Around 350,000 ground source heat pumps are installed in Sweden, providing around 10 per cent of heating needs, compared to just 7,000 in the UK.
However, with fossil fuel prices set to increase in the future and ambitious climate change targets to cut carbon emissions coming into force, the Royal Academy of Engineering believe it is time to re-examine the issue.
According to David Banks, a consultant engineer, the cost of installing a heat pump for one house was not worth it in the current climate.
However, large public buildings like schools and hospitals can make back the investment of hundreds of thousands of pounds within 10 years.
Homes in rural areas that rely on bringing in heating oil may also be able to make back the money in a relatively short period.
"We are sitting on top of a gigantic, free reservoir of natural heat in the ground - ubiquitous and available to all," said Banks.
"The cost of a ground source heat pump for a large project can be half that per unit of energy than that of a residential scheme. Thus, ground source heat can make genuine sense for offices, schools, hospitals and public buildings," he added.