Boreholes up to two miles (3.2km) deep will be drilled in Manchester to use a thermal spring to heat homes.
Proposals by GT Energy for the exploratory drilling in the Ardwick area have been approved by the council.
If the two boreholes are successful, further plans will be submitted to create a network of underground pipes taking heat to houses.
GT Energy says it will reduce energy costs for 6,000 homes and businesses.
Source: BBC News