In 2008, OPG had approximately 12,000 regular employees and generated 107.8 terawatt hours (TWh) of electricity.

OPG’s electricity generating portfolio as of December 31, 2008, had a total in-service capacity of 21,748 megawatts
(MW), which consisted of:

• three nuclear generating stations with a capacity of 6,606 MW
• five fossil-fuelled generating stations with a capacity of 8,177 MW
• 64 hydroelectric generating stations with a capacity of 6,963 MW, and
• two wind power turbines with a capacity of 2 MW.

In addition, OPG and TransCanada Energy Ltd. co-own the Portlands Energy Centre gas-fired generating station.
OPG, ATCO Power Canada Ltd. and ATCO Resources Ltd. co-own the Brighton Beach gas-fired generating station. OPG also owns two other nuclear generating stations, which are leased on a long-term basis to Bruce Power L.P. (“Bruce Power”).

Electricity Terms
One megawatt (MW) is one million watts. Megawatts are a measure of electricity supply capacity at a point in time.

One kilowatt (kW) is 1,000 watts; one gigawatt (GW) is one billion watts; and one terawatt (TW) is one trillion watts.

One kilowatt hour (kWh) is a measure of electricity demand per hour by customers. One kilowatt hour is the energy expended by fifty 20-watt compact fluorescent lights burning for one hour.

The average Ontario household uses approximately 1,000 kWh per month.

One megawatt hour (MWh) is 1,000 kWh; one gigawatt hour (GWh) is one million kWh;
and one terawatt hour (TWh) is one billion kWh.