PPG Industries flat glass business unit has said that it can now manufacture heat-strengthened glass in thicknesses of less than 3mm, which makes it among the first major glass manufacturers in North America to offer this capability. PPG offers the SOLARPHIRE glass in heat-strengthened configuration with thicknesses of 2, 2.5 and 2.7mm.
The added strength gives thin glass used in various solar applications that require resistance to wind load, hail impact and other environmental hazards the ability to meet UL and IEC (International Electrotechnical Commission) standards as well, which may help solar-module and solar-mirror manufacturers in North America.
When incorporated into solar modules, heat-strengthened thin glass permits more sunlight to reach the active layer, which enhances the conversion of sunlight into energy and increases power output. With 2mm SOLARPHIRE glass, solar transmittance is claimed to be improved by 0.3% compared to 3.2mm glass and by 0.5% compared to 4mm glass. Heat-strengthened thin glass is also claimed to give PV manufacturers the opportunity to cut downstream costs by eliminating traditional protective plastic or polyvinyl fluoride (PVF) backing sheet material. When used in solar mirrors for CSP and CPV applications, heat-strengthened thin glass enables manufacturers to cold-bend reflective (mirror) glass into shorter-radius support frames with less chance of stress breakage. This can be less expensive and simpler than doing so with thick glass that is thermally bent before mounting. Cold-bending thin glass can reduce freight costs when mirrors are shipped flat directly to field sites for installation. Thin glass also significantly increases the reflectivity and related energy output of solar mirrors, according to the company.
PV, CPV and CSP modules.
PPG can produce heat-strengthened glass in thicknesses of 2, 2.5 and 2.7mm with surface-compression strength that exceeds that of fully tempered glass (greater than 10,000 pounds per square inch), while achieving ASTM C1048 standards for flatness.
November 2012 onwards.