GT Solar Receives $228 Million Order for Polysilicon Production Equipment and Technology from South Korean Polysilicon Producer

MERRIMACK, N.H.--([ BUSINESS WIRE ])--GT Solar International, Inc. (NASDAQ: SOLR), a global provider of polysilicon production technology, and sapphire and silicon crystalline growth systems and materials for the solar, LED and other specialty markets, today announced that it has received its largest order to date for polysilicon production equipment and technology totaling $228 million from South Korea-based polysilicon producer OCI Company, Ltd. The production equipment will be incorporated into OCIa�s new Phase 4 production facility. The orderwill be included in GT Solara�s backlog for its current Q1 FY12, which ends on July 2, 2011.

"We continue to drive down the cost of polysilicon production by delivering technology that improves throughput and lowers operating expense."

aOCI is a long-time valued partner and we are proud that our polysilicon production technology has been selected for their new production facility,a said Tom Gutierrez, GT Solara�s president and CEO. aWe continue to drive down the cost of polysilicon production by delivering technology that improves throughput and lowers operating expense."

OCI expects to complete construction of its 20,000 metric ton Phase 4 production plant by the 4^th quarter of 2012. When the plant becomes fully operational it is expected to increase OCIa�s total production polysilicon capacity to 62,000 metric tons annually.

GT Solara�s polysilicon production equipment includes the industrya�s most productive and energy efficient CVD reactors and a full range of technology including hydrochlorination, filament and product processing equipment to provide a complete end-to-end production solution.

About GT Solar International, Inc.

GT Solar International, Inc. is a global provider of polysilicon production technology, and sapphire and silicon crystalline growth systems and materials for the solar, LED and other specialty markets. The company's products and services allow its customers to optimize their manufacturing environments and lower their cost of ownership. For additional information about GT Solar, please visit [ www.gtsolar.com ].

Forward-Looking Statements

Some of the statements in this press release are forward-looking in nature, including statements regarding expected revenue from customer contracts.These statements are based on managementa�s current expectations or beliefs.These forward-looking statements are not a guarantee of performance and are subject to a number of uncertainties and other factors, many of which are outside the Companya�s control, which could cause actual events to differ materially from those expressed or implied by the statements.Factors that may cause actual events to differ materially from those expressed or implied by our forward-looking statements include the possibility that the Company is unable to recognize revenue on customer contracts, that technological changes could render existing products or technologies obsolete, the Company may be unable to protect its intellectual property rights, competition from other manufacturers may increase, exchange rate fluctuations and conditions in the credit markets and economy may reduce demand for the Companya�s products and various other risks as outlined in GT Solar International, Inc.a�s filings with the Securities and Exchange Commission, including the statements under the heading aRisk Factorsa in the Companya�s annual report on Form 10-K for the fiscal 2010 filed on June 4, 2010 and the quarterly report on Form 10-Q for the third quarter of fiscal 2011 filed on February 10, 2011. GT Solar International, Inc. is under no obligation to, and expressly disclaims any such obligation to, update or alter its forward-looking statements, whether as a result of new information, future events, or otherwise.

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GT Solar Receives $228 Million Order for Polysilicon Production Equipment and Technology from South Korean Polysilicon Producer