External reflectors for large solar collector arrays, simulation model and experimental results

摘要: A model for the calculation of incident solar radiation from flat-and CPC-shaped external reflectors onto flat plate collector arrays has been developed. Assuming an infinite length collector/reflector rows, basic calculations in plane reflector become very simple. The direct sun is projected into a vertical perpendicular to and plane. collector, including corrections shadowing lost above can then be calculated using 2-D geometry. For short rows 3-D given correction loss specular east west direction. diffuse assumed isotropic. view factors. treated with same models by introducing equivalent reflector. incidence angle most cases higher than directly sun. Therefore characteristics glazing absorber more important this application. Equations are anglesmore » beam radiation. An annual performance increase over 30%, 100-120 kW h/m[sup 2], measured aged (four operating seasons) Swedish climate. With new materials, up 170 2] not unrealistic. This means that ground area requirement reduced 30% load.« less