The plans, which will deliver up to 100 MW of renewable energy by 2016, are part of Sainsbury’s 20 by 20 Sustainability Plan to cut carbon emissions 30% and provide renewable heating for its supermarkets by 2030.
The supermarket chain has already employed geothermal technology at its Crayford store in south-east London, where it supplies some 30% of the store’s energy requirements.
On that project, E.ON worked with thermal energy specialist Greenfield Energy on a pioneering borehole technology, which enables large-scale geothermal installations on minimal land area.
A further 100 new-build and existing stores have now been identified by Sainbury’s, E.ON and Geothermal International for the installation of new geothermal heat pump technology.
The technology works by pumping cold water into the ground where it is warmed up. The warmed water is then returned to a heat pump, which extracts the heat and delivers it to the building, before returning the cold water back into the system to be pumped into the ground again.
Geothermal International is being supported by Octopus Investments in the installation of the ground source heat pumps for Sainsbury’s in its store carparks.
“The roll out of this technology with our partners is an important milestone in our renewables commitment,” says Sainsbury’s property director Neil Sachdev. “We were the world’s first to use geo-thermal technology in a supermarket to tap natural, renewable energy trapped 600 feet under the ground.”
The supermarket is also working on reducing its absolute electricity usage and has achieved a 9% reduction over the past four years despite an increase in retail space.
Sainsbury’s is also installing biomass boilers, which run off wood chips or pellets, and is the largest UK user of anaerobic digestion with all of its food waste from stores not donated to food charities being used to generate electricity for the grid.
UK and Iceland sign pact on geothermal energy (31-May)
Prince of Wales to invest in energy-from-waste enterprise (23-Feb)
Sainsbury’s sets out stall for £1 billion sustainability plan (12-Oct 2011)
Article source: http://www.energyefficiencynews.com/i/5289/