Capstone Turbine Corp. shares fell more than 10 percent on Friday after the maker of turbines for power generation uses priced a $40 million secondary offering.

The Chatsworth company priced the offering of 38 million shares at $1.06 per share. Net proceeds, after deducting the underwriter’s discounts and other estimated offering expenses, are expected to be $36.8 million. The company first announced the offering after Thursday’s market close.

The company also granted the underwriter, Lazard Capital Markets LLC, a 30-day option to buy more shares that could increase gross proceeds to $46 million.

Capstone plans to use the money for product development and for general corporate purposes. Among Capstone’s newer products are turbines used in battery-charging generators for hybrid electric vehicles.

Capstone shares were down 13 cents, or 10.5 percent, to $1.11 in midday trading on the Nasdaq.