For anyone interested in science and fellow environmentalists --
Solar Power World - May 2, 2012
"3Mís Renewable Energy Division has teamed with Gossamer Space Frames to unveil a new parabolic trough solar collector technology designed to significantly reduce equipment and installation costs for CSP systems used in power generation. The Large Aperture Trough 73 (LAT 73) features a concentration factor of over 100x and an aperture size of 7.3 m, both world benchmarks for the industry. ..."
FYI, that's a collector about 24 feet across and only made possible by replacing the glass mirrors typically used. Instead a 0.2 inch piece of acrylic, backed with a layer of highly reflective silver, is adhered to aluminum. 3M calls this Solar Mirror Film 1100 and, including the aluminum backing, weighs 50% of a typical mirror.
3M technical data Jan 2012 (one page)
While only recently reveled, this demonstration array has been operating since October and only produces 275kW peak output, but due to a total cost 25% lower than typical trough designs, is promising. What's even more promising is solarthermal may finally move away from glass mirrors permanently.
The next leap in solarthermal can only come once it moves from concentration via reflection and starts using refraction. Silver backing (near 100% reflective) is expensive and the aluminum structure required is still heavy and costly. Polycarbonate Fresnel lenses of similar thickness (0.2 inches) would be just as effective as the acrylic mirrors mentioned above, but the system significantly cheaper and lighter. Above is a Fresnel concentrator for the unfamiliar, though for an effective expanse of Polycarbonate it would likely need to be slightly curved and framed to maintain it's shape.