55 ILCS 5/5-4001: Contracts with municipality.

In any county of 500,000 population or over having a public building or buildings owned by said county, adjacent or contiguous to a public building or buildings belonging to any municipality within such county, such county and municipal corporation may contract with each other, and they are hereby empowered to sell and deliver, one to the other, heat or electricity from the plant or plants located in the building or buildings of one for use in such building or buildings of the other, and it shall not be necessary to advertise for bids before entering into contracts hereunder: Provided, however, that a saving over previous expenditures must thereby be secured to either or both.