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EXHIBIT 23.1

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

        We consent to the reference to our firm under the caption "Experts" and to the use of our report dated March 24, 2010 in Amendment No. 7 to the Registration Statement (Form S-1 No. 333-152671) and related Prospectus of First Wind Holdings Inc. dated August 18, 2010.

/s/ Ernst & Young LLP              

Boston, Massachusetts
August 16, 2010

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EXHIBIT 23.1

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM