The â‚¬1.3 million energy project uses sea water from the Bassin du Commerce that has a constant temperature of around 12 degrees. It is fed into two heat source pumps that transfer the heat from the water to the domestic water supply at 62 degrees.
Currently 1,300 apartments in 27 buildings in the Divette area of the city 300 meteres from the dock are being supplied by the system and there are plans for it to be expanded.
Housing Association Presquâ€™Ã®le Habitat persuaded the owners of a number of residential buildings in the area to join the project. A spokesman said that home owners should see their energy bill reduced and will no longer be subject to gas and oil heating price rises that have been all too common recently.
It is estimated that 84% of domestic hot water and heating will be provided by the new pump and the rest by a gas boiler when the sea water temperature falls during periods of extreme cold.
Energy services company Dalkia, which is managing the new heating systems, said the system will reduce the C02 footprint of the buildings by 62%, the equivalent of the consumption of 830 vehicles a year.
The firm is also working with the Manche local council to reduce energy performance in other areas including 20 schools, three museums, and the council headquarters in St Lo.
A spokesman said that the result will be a 58% reduction in the CO2 emissions of the buildings, a guaranteed 32% in energy savings for 15 years and improved comfort for users of the facilities.
â€˜The energy renovation program is very much in line with the innovative initiatives being taken by the Conseil GÃ©nÃ©ral to promote sustainable development as part of its PlanÃ¨te Manche Agenda 21 programme,â€™ said a Manche council spokesman.
Local councils throughout France are being encouraged to reduce their energy costs. France’s Grenelle Environment Forum has recommended that they should reduce the carbon footprint of their real estate assets by 38% by 2020.
In Manche the energy efficiency programme will include insulating the buildings to avoid energy losses and using wood to heat the buildings which will involve the installation of 14 heat plants fired by wood energy, which is renewable and very low in CO2 emissions.
Low energy lighting will be installed along with remote management systems to monitor and manage energy consumption in the buildings. The occupants of the schools and Conseil GÃ©nÃ©ral sites to be renovated will also receive help with how to make energy savings and use eco friendly behaviour on a daily basis.