SAN FRANCISCO, CALIFORNIA–(May 5, 2014) – Pattern Energy Group Inc. (the “Company” or “Pattern Energy”) (NASDAQ:PEGI)(TSX:PEG) today announced the commencement of an underwritten public offering of up to US$400 million of shares of its Class A common stock by the Company and selling shareholder Pattern Energy Group LP (the “selling shareholder” or “Pattern Development”). The underwriters of the offering will have the option to purchase up to an additional 15% of that amount from the selling shareholder to cover over-allotments.

The Company will use the proceeds of its portion of the offering for working capital and general corporate purposes, including the acquisition of the Panhandle 1 wind power project from Pattern Development and potentially including certain other wind power projects. As separately announced on May 2, 2014 the Company has agreed, subject to customary closing conditions, to acquire Panhandle 1 from Pattern Development shortly after its commencement of commercial operations, which the Company expects to occur in June 2014.

The offering is being made through an underwriting group led by BMO Capital Markets, Morgan Stanley & Co. LLC and RBC Capital Markets, who are acting as joint book-running managers of the offering and the representatives of the underwriters.

This offering will be made only by means of a prospectus. Copies of the preliminary prospectus and final prospectus relating to the offering may be obtained when available from BMO Capital Markets, Attn: Equity Syndicate Department, 3 Times Square, New York, NY 10036, or by telephone at (800) 414-3627 or by email at bmoprospectus@bmo.com; Morgan Stanley & Co. LLC, Attn: Prospectus Department, 180 Varick Street, 2nd Floor, New York, NY 10014, or by telephone at (866) 718-1649 or by email at prospectus@morganstanley.com; or RBC Capital Markets, LLC, Three World Financial Center, 200 Vesey Street, 8th Floor, New York, NY 10281, Attn: Equity Syndicate, or by telephone at (877) 822-4089 or by email at syndicateops@rbccm.com.

A registration statement relating to these securities has been filed with the Securities and Exchange Commission but has not yet become effective. These securities may not be sold nor may offers to buy be accepted prior to the time the registration statement becomes effective. The offering will be made in Canada under a supplement to the Company’s base shelf prospectus filed with Canadian securities regulatory authorities. This press release shall not constitute an offer to sell or a solicitation of an offer to buy, nor will there be any sale of these securities in any state or jurisdiction in which such an offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of any such state or jurisdiction.

About Pattern Energy

Pattern Energy Group Inc. is an independent power company listed on the NASDAQ and Toronto Stock Exchange. Including the pending acquisitions of the Panhandle 1 and Panhandle 2 projects, which the company has agreed to acquire from Pattern Energy Group LP, Pattern Energy owns interests in eleven wind power projects located in the United States, Canada and Chile that use proven, best-in-class technology and have a total owned capacity of 1,434 MW. Pattern Energy’s wind power projects generate stable long-term cash flows in attractive markets and provide a solid foundation for the continued growth of the business.

Cautionary Statement Concerning Forward-Looking Statements

Certain statements contained in this press release constitute “forward-looking statements” within the meaning of the Private Securities Litigation Reform Act of 1995 and “forward-looking information” within the meaning of Canadian securities laws, including statements regarding the proposed public offering, acquisitions and use of proceeds. These forward-looking statements represent the Company’s expectations or beliefs concerning future events, and it is possible that the results described in this press release will not be achieved. These forward-looking statements are subject to risks, uncertainties and other factors, including conditions to closing this offering, many of which are outside of the Company’s control, which could cause actual results to differ materially from the results discussed in the forward-looking statements.

Any forward-looking statement speaks only as of the date on which it is made, and, except as required by law, the Company does not undertake any obligation to update or revise any forward-looking statement, whether as a result of new information, future events or otherwise. New factors emerge from time to time, and it is not possible for the Company to predict all such factors. When considering these forward-looking statements, you should keep in mind the risk factors and other cautionary statements in the prospectus filed with the SEC and applicable Canadian securities regulatory authorities and incorporated by reference therein from the Company’s annual report on Form 10-K. The risk factors and other factors noted in the prospectus could cause actual events or the Company’s actual results to differ materially from those contained in any forward-looking statement.