Solar company STR Holdings Inc priced its initial public offering of 12.3 million shares at $10 a share on Friday, below the target range and a day later than expected.

The Enfield, Connecticut-based company, which makes parts called solar power module encapsulants, started trading on the New York Stock Exchange under the symbol STRI up 3 percent at $10.36.

The company on Thursday cut the price range of the IPO -- the first from a U.S.-listed solar company in more than a year -- to between $11 and $13, down from a previous estimate of $13 to $15 price.

STR was founded in 1944 as a plastics research and development company. Its encapsulants protect a solar module's semiconductor circuit.

The company plans to use $15 million from the offering to pay down debt, with the remainder for working capital and general corporate purposes, according to its offering prospectus.

In the first half of 2009, STR had sales of $117.7 million, down 14 percent from the year-earlier period, and net income of $6.2 million. It counts BP Solar, First Solar and SunPower Corp among its clients.

The last solar company to go public in a U.S.-listed IPO was GT Solar International Inc last summer; its shares have fallen almost 60 percent since then.

Solar stocks have struggled as the recession has tightened financing for solar projects, but experts are hopeful the first installment of green stimulus dollars next year will help the industry.

The STR IPO was lead managed by Credit Suisse Group and Goldman Sachs Group. Underwriters will have an option to buy an additional 1.845 million shares from the selling stockholders.

(Reporting by Elinor Comlay; editing by John Wallace)