Engie will deliver energy and carbon reduction services to Milton Keynes council via an energy performance contract that guarantees savings.
The first phase of the contract aims to improve local authority owned buildings including sheltered housing. Further phases will likely involve large scale renewable generation projects with investment potentially upward of £50m.
The seven year facilities management contract has a three-year extension option.
Both contracts will commence before the year end.
Milton Keynes Council aims to be carbon neutral by 2030 and carbon negative by 2050.
“We want MK to be the world’s first post-carbon city, and how we manage our own assets is an important step towards this goal,” said Council leader Pete Marland.