Ontario Power Generation

OPG News Release, May 30, 2006

May 30, 2006

ONTARIO POWER GENERATION'S SHORT-TERM CREDIT RATING UPGRADED BY STANDARD AND POOR'S

[Toronto]: Standard & Poor's (S&P) has recognized Ontario Power Generation's (OPG) improving performance and prospects and announced that it has raised OPG's short-term Canadian scale Commercial Paper (CP) debt rating to ‘A-1(Low)' from ‘A-2'. At the same time, S&P affirmed OPG's ‘BBB+' long-term corporate credit rating and ‘A-2' global scale CP rating. The outlook is positive.

In making its announcement, S&P said the change in the short-term rating reflects: a significant improvement in OPG's ability to manage cash flow pressures, a formal process for project review and for obtaining financing from the Ontario Electricity Financial Corporation (OEFC), and a reduction in intra-month cash volatility through better working capital management. For more information refer to the S&P press release of May 25.

The announcement follows S&P's decision on September 27, 2005 to affirm OPG's long-term corporate credit rating at ‘BBB+' and revise its outlook to "positive" from "developing".

Ontario Power Generation Inc. is an Ontario-based electricity generation company whose principal business is the generation and sale of electricity in Ontario. Our focus is on the efficient production and sale of electricity from our generation assets, while operating in a safe, open and environmentally responsible manner.

For more information contact:
Ontario Power Generation Media Relations
(416) 592-4008 or 1-877-592-4008
or
Investor Relations
(416) 592-6700