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Exhibit 23.1
Consent of Independent Registered Public Accounting Firm
We consent to the reference to our firm under the captions "Summary Consolidated Financial Information", "Selected Historical Financial Data" and "Experts" and to the use of our report dated June 5, 2008, in Amendment No. 3 to the Registration Statement (Form S-1 No. 333-142383) and related Prospectus of GT Solar International, Inc.
| /s/ Ernst & Young LLP |
Boston, Massachusetts
June 5, 2008
Consent of Independent Registered Public Accounting Firm