Business Green: US utility Exelon has stepped up its push into the renewable energy sector, announcing that has agreed to shell out $860m to acquire John Deere Renewables, the wind energy subsidiary of engineering firm Deere & Co. The Chicago-based company said the deal, which is expected to close before the end of the year, would give it control of 735MW of wind energy capacity, as well as an further 230MW that are in advanced stages of development. The acquisition is valued at around …