POCATELLO, Idaho — Trying to build a new plant to meet the increasing demand for polysilicon for the solar-power industry, Hoku Scientific Inc. is amending its agreements with two big customers.

The Kapolei, Hawai'i-based company and Sanyo Electric Co. agreed to amend their polysilicon supply agreement to provide Hoku with six additional weeks to secure financing to build its plant in Idaho. The new deadline is Feb. 15.

Hoku and Solar-Fabrik AG also amended terms of their supply agreement so that Hoku will provide the company with less polysilicon at higher prices. The revision was the result of Solar-Fabrik's failure to provide a second standby letter of credit by Sept. 30. It already had provided $2 million, plus $25 million in credit, as prepayment for future deliveries.

Hoku provides polysilicon to the solar-power industry to use for photovoltaic products.

Sanyo, Solar-Fabrik, Suntech Power Holdings Co. and Solarfun Power Holdings Co. have committed to prepay a combined $240 million for future shipments to fund the plant.

Sanyo's $370 million contract required an initial $2 million deposit with Hoku and a deposit of about 30 percent of the total into an escrow account to be released in installments.

Meanwhile, Hoku announced in a regulatory filing that it will pay Idaho Power Co. $14.8 million to construct a power substation for its Idaho plant. The company has agreed to make an initial payment of $3.7 million by Tuesday.

The power substation and related facilities are to be completed by Feb. 15, 2009. Meanwhile, the power company will charge Hoku for temporary power to start up operations before the deadline.

Hoku's plant in Pocatello, when completed, will provide polysilicon to the solar-power industry, which uses polysilicon as a key component for its products. Polysilicon demand and prices have risen significantly as supplies have come under pressure.

Hoku said it plans to borrow up to $185 million for the Idaho plant.

"We continue to commit capital to the design and engineering of our plant, and to the purchase of long lead-time items such as the reactors, to stay on schedule for our planned 2009 product deliveries," Hoku Chief Executive Dustin Shindo said in a statement.

Separately, investment bank America's Growth Capital said it has initiated coverage of Hoku Scientific, assigning an intrinsic equity value of $15.79 per share.

The Boston-based investment bank said the valuation was based on its expectations of discounted free cash flow for Hoku. It said any debt or equity offering in the future has the potential to affect Hoku's share price.

In trading yesterday, Hoku Scientific shares gained $1.09, or 9.6 percent, to $12.49.

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