The Dolonne hydroelectric plant, in operation since 2010, is SEVA's most important plant in terms of energy capacity and production.
The flowing-water power plant is composed of: a water-intake composed of a crossbeam, a grit separator, a holding tank and a penstock of about 1900 m in length. The production centre, located in a pre-existing building, contains 4 horizontal-axis Francis turbines.
The water intake is located just downhill of a glacier which means that, especially during the summer, the arriving water is characterized by an enormous load of solid material. To obviate this problem a grit separator with two parallel tanks, was contructed; which allows one tank to be cleaned without interrupting the hydroelectric sourse. The mechanical parts that are most subject to wear have been treated with a special coating.