The volume of water flowing through plumbing in a given period of time. Usually measured in volume/minute or volume/hour.
Flat Plate Collector
A solar collection device in which sunlight is converted into heat on a plane surface without the aid of reflecting surfaces to concentrate the rays.
Posted in Glossary of Terms Leave a comment
Eutectic Salts
A group of materials that melt at low temperatures, absorbing large quantities of heat.
Posted in Uncategorized Leave a comment
Emittance
A measure of the propensity of a material to emit thermal radiation.
Posted in Uncategorized Leave a comment
Efficiency
Solar collector efficiency is usually expressed as a percentage value, or in a performance graph. When assessing a collector’s performance make sure it is based on the correct surface area values.
Posted in Glossary of Terms Leave a comment
Drain down System
Potable water is circulated from the storage tank through the collector loop. Freeze protection is provided by solenoid valves opening and dumping the water at a preset low temperature. Collectors and piping must be pitched so that the system can drain down, and must be assembled carefully to withstand 100 psi. city water line pressures. Pressure reducing valves are recommended when city water pressure is greater than the working pressure of the system.
Posted in Glossary of Terms Leave a comment
Direct Radiation
Solar radiation that comes straight from the sun, casting shadows on a clear day.
Posted in Glossary of Terms Leave a comment
Direct Methods
Techniques of solar heating in which sunlight enters a house through the windows and is absorbed inside.
Posted in Glossary of Terms Leave a comment
Diffuse Radiation
Indirect sunlight that is scattered from air molecules, dust and water vapor.
Posted in Glossary of Terms Leave a comment
Forced Convection
The transfer of heat by the flow of fluids (such as air or water) driven by fans, blowers or pumps.