In 1916, the Oshawa Electric Company, which was run by the Seymour Power Company, was purchased by the Ontario Government and placed under the control of the Hydro-Electric Power Commission of Ontario. This Commission was set up in 1905 by the provincial government to obtain and provide electrical power at cost to municipalities on a province-wide basis.During the years following the First World War, Oshawa expanded to become a thriving industrial city and the demand for more light and power increased dramatically.
Hydroméga devient le premier producteur indépendant au Québec dans le cadre de la politique des petites centrales hydroélectriques établie en 1987 par le Gouvernement du Québec et Hydro-Québec.