Chevron Corp will unveil on Monday a solar oilfield project that has been hit by cost overruns and delays but serves as a showcase for the technology of Chevron-backed solar thermal company BrightSource Energy.

The second-largest U.S. oil company said on Friday three of its executives would attend the launch of the demonstration project in Coalinga, California, which is designed to use solar power to create steam to inject into wells to improve the flow of heavy oil.

The project covers 65 acres, consisting of 7,600 mirrors focusing sunlight on a 327-foot (100-meter) tower.

Success in Coalinga, which expanded greatly in the California oil boom more than a century ago, would be a boost for solar thermal technology, as many other projects have been scrapped in favor of photovoltaic systems.

BrightSource, which filed with U.S. securities regulators for an initial public offering in April, said in an amended filing in June that it set aside $40.2 million to account for losses since the Coalinga project's inception, $29.7 million more than originally anticipated.

The Oakland, California-based solar company blamed the cost overruns on design and engineering changes, weather-related delays and efforts to speed up completion of the project.

Sergio Hoyos, a business developer at Chevron Technology Ventures, told Coalinga residents in August 2009, before building began, that it would start up by the end of 2010.

Besides Chevron, other BrightSource investors include Google Inc, ALSTOM, BP Plc, Morgan Stanley and VantagePoint Capital Partners.