The energy giant was part of a joint venture on two sites in Ferrybridge and one in Skelton Grange, but, as part of its strategy to raise £2 billion by next year, SSE will continue to focus on its wind farm operations.
In a statement, SSE said: "SSE plc has entered into an agreement to sell its 50% share in energy-from-waste ventures Multifuel Energy Limited (MEL1) and Multifuel Energy 2 Limited (MEL2) to European Diversified Infrastructure Fund III, an infrastructure fund managed by First Sentier Investors, for a total cash consideration of £995m.
"The transaction is expected to complete by late 2020 subject to antitrust approval by the European Commission.
"MEL1 and MEL2 are 50-50 joint ventures between SSE and Wheelabrator Technologies Inc., consisting of the operational Ferrybridge Multifuel 1 and Ferrybridge Multifuel 2 facilities (MEL1), as well as the Skelton Grange Multifuel development project (MEL2), all in West Yorkshire."
"In June 2020, SSE identified its interests in MEL1 and MEL2 as an early priority for sale as part of a strategy to secure at least £2bn from disposals of non-core assets by autumn 2021. Today's announcement follows the sale of SSE's 25.1% non-operating stake in Walney Offshore Wind Farm to Greencoat UK Wind for £350m and the agreement to sell its 33% equity interest in meter asset provider MapleCo to Equitix, under which SSE will receive net proceeds of around £90m on closing.
"The proceeds of these disposals will support the company's plans to invest £7.5bn in low-carbon energy infrastructure over the next five years, helping the UK to reach net-zero carbon emissions, as well as reduce SSE's net debt."
Gregor Alexander, Finance Director , said: "This sale marks a major step in our plans to secure at least £2bn from disposals by autumn 2021, with just over £1.4bn now delivered.
"While these multifuel assets have been successful ventures for SSE, they are non-core investments and we are pleased to have agreed a sale that delivers significant value for shareholders while sharpening our strategic focus on our core low-carbon businesses.
"Our disposal programme demonstrates how the company can create value from our assets and supports our plans to invest £7.5bn over the next five years in the low-carbon infrastructure needed to stimulate a green economic recovery and help the UK transition to a net-zero future."