UPDATE:Capstone Turbine Shares Up This Week On Engineering News

Shares of green microturbine maker Capstone Turbine Corp. (CPST) nearly doubled this week on news that U.K. auto engineers have fit its turbines into a modified electric-and-biodiesel Ford S-Max sedan with gas mileage of 80 miles per gallon.

The "clean" microturbine engine component maker, based in Chatsworth, Calif., surged to $1.32 on Thursday after closing the previous day at 73 cents a share. In recent trading Friday, its shares were off about 10% from Thursday's closing. Over the last 52 weeks, Capstone shares have traded as high as $4.42 and as low as 39 cents.

The Dow Jones Sustainability Index, a leading indicator of environmentally friendly shares, is up by about a third since its early March lows. Capstone isn't part of the index.

Langford Performance Engineering Ltd., in Wellingborough, England, fit the liquid-fueled microturbine into the modified Ford it calls the "Whisper Eco-Logic."

Using a turbine about doubles the gas mileage of its combined battery-powered and diesel/biodiesel engine, said Dick Langford, managing director of the auto modifier.

"We wanted to prove that you could make a practical vehicle that is also environmentally friendly," he said. "This can be used as an everyday car."

"The design characteristics of Capstone's turbine permits ultra low emissions, high fuel economy, multi-fuel capability, no coolants or lubricating oil, and little to no maintenance in an automotive application," Jim Crouse, Capstone executive vice president, said in a prepared release.

Capstone is due to announce its fiscal fourth-quarter and 2009 earnings on June 15.

New York-based Ardour Capital Investments LLC expects a loss of 6 cents a share on quarterly sales of $11.9 million. It rates Capstone a hold. "We expect them to continue approaching gross margin break-even in the fourth quarter," Ardour senior equity-research associate Meghan Moreland said.

On average, analysts polled by Thomson Reuters expect the company to post a loss of 6 cents on revenue of $13.4 million.

-By Brendan Conway, Dow Jones Newswires; 201-938-5394