Concentrating on Solar PV  

The Climate Spectator reports that Silex's long delayed CPV plant for Mildura in Victoria may at last be moving ahead - All Systems go.

Silex Systems has finally secured formal agreement from the federal government to continue the $75 million of fund granted to a proposed 152MW concentrated solar project in Mildura. The fate of the grant had been in some doubt, because the company that originally received the grant, Solar Systems, went bankrupt in late 2009 before being bought by Silex early in 2010. Silex says the grant – combined with $50 million in funds from the Victorian government – will enable the company to progress to a 2MW pilot plant, then a 100MW demonstration project that could be expanded by a further 50MW at a later date.

Silex says it has refined and solved many of the technical difficulties that had plagued the original project, and which had forced the company into receivership because its shareholders, which include TRUenergy and several private, either couldn’t or wouldn’t provide more funds. The unique 'dense array' concentrating PV technology is said to be deal for large commercial and utility-scale solar projects, and Silex says the Mildura facility has the potential to be of the one of the largest and most efficient solar power stations in the world.

Silex says it continues to investigate opportunities to construct utility-scale solar plants in Australia and US, as well as growth opportunities worldwide. The $75 million of Commonwealth funding was announced in 2006 as part of the Low Emissions Technology Demonstration Fund. The Federal Government has further assisted the project with a $4.5 million grant under the Asia Pacific Partnership on Clean Development and Climate, of which approximately $1.9 million was transferred to Solar Systems.

With a 150 MW project planned in San Diego and a 25-year PPA in place, CPV has at last entered the commercial arena. Standing in the New Mexico desert, a 1 MW Concentrating Photovoltaic (CPV) power plant is establishing a route for the emergence of this utility-scale technology. Installation of this first pilot commercial deployment began in the summer of 2010 and the plant was commissioned early in 2011, with official inauguration in April.

Located on the tailings site of Chevron Mining Inc's (CMI) molybdenum mine in Questa, New Mexico, some 2000 metres above sea level in an area of the US noted for its high levels of Direct Normal Irradiance (DNI), its developers say the project will demonstrate the technology as well as a practical use of previously impacted land. Electricity produced from the installation will be sold to the Kit Carson Electric Cooperative, through a power purchase agreement.

Covering some 20 acres (8 ha) the site has 173 CPV modules, each of which has an area of about 18 by 21 feet (35 m²) and is pole mounted on dual axis trackers supplied by a major manufacturer. The Concentrix technology uses Fresnel lenses to concentrate sunlight almost 500 times onto high efficiency multi-junction PV cells. With this technology, Soitec claims to achieve AC system efficiencies of 25% and more, significantly higher than currently available conventional solar PV technology, and as a result, cost reductions of 10%-20% could be reached, depending on the location of the installation, it says. ...

CPV systems are typically more efficient than conventional solar systems at locations with both high ambient temperatures and dry weather conditions. Because of the very low temperature coefficient of its solar cells, a CPV system's performance is much less affected by temperature than other photovoltaic technologies. Another key advantage of CPV technology is the very low levels of water required for operations, essentially used in cleaning only, a crucial consideration for the water-constrained regions to which it is suited, such as the Imperial Valley, which is some 150 miles (230 km) from the coast.

Indeed, such technology is expected to work best in areas with higher DNI like northern New Mexico and southern California, as well as in north and southern Africa, the Middle East, and much of China and India. Certainly, in 2010 Soitec announced that it had joined the Desertec Industrial Initiative (Dii) as Associated Partner and Medgrid as a founding member, in the expectation that the decision will pave the way to utility-scale CPV projects in the Middle East and North Africa (MENA).