The wholesaler has signed a 25m contract with Airtricity, which will supply Musgrave stores across Ireland.
SuperValu, Centra and Daybreak stores in the Republic and SuperValu, Centra and Mace stores in Northern Ireland are all included in the deal via an affinity scheme. The green contract was the largest of its kind in Ireland, Musgrave Group said.
"Mitigating climate change impact and reducing our dependence on fossil fuels is crucial," said John Curran, environmental executive for Musgrave.
"As well as lowering emissions of CO2 and other greenhouse gases, this agreement will also result in reduced energy costs and underscores the value of continuing to focus on driving our sustainability strategy, even in times of recession."