Under the terms of the contract, WGI will act as Exelon’s engineer of choice over the next three years, with the option to extend services by a further two years. The value of the deal, which will also include Exelon’s fossil fuel plants, has yet to be revealed.

Exelon runs two plants situated on the Susquehanna river, which together have an installed capacity of 1608MW.

Conowingo, a 536MW run-of-the-river hydroelectric scheme operated by Exelon subsidiary Susquehanna Electric Company (SEC), comprises 11 units and provides a pond for public recreational use.

SEC also operates the 1072MW Muddy Run pumped storage plant, which consists of eight units and is used for peaking and load levelling.