Toronto schools will soon become "private generators" as part of a plan to retrofit empty rooftops with solar panels starting this summer.

By September, 50 solar panels will cover the roofs of Hillcrest Community School and William Lyon Mackenzie Collegiate – the first step toward an ambitious plan to implement a renewable energy grid across the city's 558 public schools.

"We have schools in virtually every neighbourhood in the entire city. You have this vacant space on all the rooftops. These would be the perfect locations to really create a green grid across the city," said Toronto trustee Josh Matlow, who will announce the project's launch at a news conference today.

Large, flat rooftops are ideal locations for solar thermal and photovoltaic systems, and sports fields are excellent places to install geothermal systems for heating and cooling.

The energy consumed in schools can also be managed more efficiently. Occupancy and daylight harvesting sensors can cut down on non-essential lighting, and smart thermostats can do a better job of balancing heating and cooling requirements. Major work can be done with minimal disruption during summer break.

St. Basil-the-Great College School is a step closer to building a windmill on its front lawn after the Ontario government announced it is providing $50 million to help schools go green.

The money will encourage school boards to cut down heating, cooling and energy bills by installing technologies such as solar panels, geothermal systems and small-scale wind projects, Energy Minister George Smitherman said yesterday at St. Basil's in North York.

Schools that go green will not only save money on energy and natural gas bills, they can also make money by selling electricity back to the grid through feed-in tariffs, he added.

The $50 million committed yesterday is in addition to the $550 million announced in April to retrofit schools – especially older buildings in need of new boilers and windows – to save energy and create nearly 5,000 temporary jobs.

The new solar-panel cross on the front of St. Jean de Brebeuf Catholic High School in Woodbridge not only stores energy from the sun – at least enough to run a microwave oven – but also will remind students and passersby this weekend to unplug for Earth Hour, says Norman Vezina, the York Catholic District School Board's senior manager of environmental services.

Energy specialist Paul Charbonneau shared with a room full of local entrepreneurs, homeowners and teachers, how to build green thinking into our education system and our education buildings during last week's renewable energy alternatives for rural communities and businesses workshop at the Georgina Trades Training building.