Hydroelectricity has powered the lives of Ontarians for a century, and Ontario Power Generation is planning an extensive 20-year overhaul of its hydropower generating units to ensure clean, reliable hydropower continues to support the province’s wellbeing.This refurbishment takes place every 25 to 50 years across operations in the company’s Renewable Generation division. Numerous stations are reaching the critical age for major refurbishment, OPG said.