Hundreds of homes could soon be heated by the freezing waters of the North Sea after an energy project was given a £1.6 million cash boost.

The scheme is one of three in Scotland to use pumps to extract heat from water which will share £1.75 million Scottish Government funding.

The projects, in Shetland, Clydebank and Glasgow, will use innovative technology to heat homes and businesses from the sea and river water, cutting harmful carbon dioxide emissions.

A total of £1.6 million went to a scheme to heat 225 homes in Lerwick, Shetland, by pumping water from the North Sea, while a project to use water from the Clyde to create a district heating network at Queens Quay on the site of the former John Brown shipyard in Clydebank was awarded £75,000.

A further £75,000 went to a scheme aimed at pumping water from the River Kelvin to heat buildings at the new Glasgow University campus planned for the site of the former Western Infirmary.

Energy Minister Fergus Ewing made the announcement at the Scottish Renewables conference in Edinburgh.

He said: "Heat is estimated to account for over half of Scotland's total energy use and is responsible for nearly half of Scotland's greenhouse gas emissions, so the imperative to take action is very clear.

"Continued growth in the number of homes and businesses benefiting from connecting to low carbon, affordable warmth provided by district heating networks helps the Scottish Government towards realising our ambition to increase the number of connections to district heating networks by 2020."

Glasgow firm Star Renewable Energy helped pioneer the technique in the Norwegian city of Drammen, providing a water heat pump system which supplies the majority of the city's energy using water from the local fjord.

It transforms the average 8C water to 90C, and provides annual savings of around 2 million euro (£1.5 million) while removing 1.5 million tonnes of carbon - equal to taking more than 300,000 cars off the road for a year.

Star Renewable Energy director Dave Pearson said: "Drammen reduced their carbon footprint and stack emissions by over 80% by switching from gas combustion to our 90C heat pump, achieving the COP21 2050 goals stated in Paris.

"The Scottish Government commitment will be a catalyst for a similar step in Scotland as we aim for a significant decarbonisation of heating."