For what it’s worth I will provide details of the proposed solar power plant that is planned to be built near Victorville, California by Stirling Energy Systems. This is a project that was originally announced back in August 2005 as a thermal solar power plant with a capacity of 500MW, a significant contribution to electricity generated from renewable energy sources. A power purchase agreement had been signed between Stirling Energy and Edison International, a subsidiary of Southern California Edison (SCE).

Very little has been mentioned since about the SCE-Stirling proposal which was slated to be constructed on 4,500 acres of land near Victorville, about 70 miles north-west of Los Angeles. At the time of the 2005 announcement the proposal was going to be put before the California Public Utilities Commission for approval. Approval also still needs to be sought for a 1MW pilot project that was going to be completed in the first quarter of 2007. As of July 2007, according to Energy and Nature blog, that approval was with the Bureau of Land Management in Barstow was still outstanding because Stirling Solar still hadn’t supplied the BLM with data required to perform an environmental review.
 

The proposal explains that the solar facility will consist of 20,000 Stirling-engine solar dishes set on around 4,500 acres of land. This works out to be around 7 square miles. A 500MW facility such as this will provide enough power to serve 278,000 homes per year.

Each Stirling-engine solar parabolic dish is 37 feet in diameter and generates 25kW. The solar dish works by reflecting the sun’s rays onto a receiver which transmits heat energy to a Stirling engine. The engine is a sealed system filled with hydrogen. As the gas heats and cools, its pressure rises and falls. The change in pressure drives pistons inside the engine which, in turn, drives a generator to make electricity.

If the project ever gets off the ground it is expected that the construction phase of the 500MW power plant will take 4 years. The original agreement included an option to increase the capacity of the project to 850MW and the extra 350MW would take a further 2 years to construct if the option is taken.

A recent (February 2008) announcement was made by Stirling Energy Systems (SES) in partnership with Sandia, a national Nuclear Security Adminitration larboratory when a Stirling-engine set a new solar-to-grid system conversion efficiency record by achieving a 31.25% net efficiency rate. This was achieved at a 6 dish test facility erected in May 2005 in New Mexico producing up to 150kW of electrical power.

As part of the announcement SES president and CEO Bruce Osborn mentioned that the company has signed the power purchase agreement with So Cal Edison but gave no sign on the progress, if any, that had been made on the project.

A little disturbing is when trying to find out more about Stirling Energy Systems on their website, it turns out the site has been removed. Hopefully this is only a temporary thing.