Full Description

Agricultural applications for solar energy are different from most residential and commercial applications because there are several uses for- low-temperature-rise (1 to 10° C° or 2 to 20 F) thermal energy. Thermal efficiencies of 10% to 50% are possible with low-cost systems (as low as $1.00/ft² or $10.00/m²) because there is a lower temperature difference between the absorber and outdoors. Multi-use solar systems are also possible because the low-temperature thermal energy needs on the farmstead are often in close physical proximity.

Costs and reliability are the most limiting factors for agricultural solar systems. Economic analyses considering all installation and operating costs have shown solar systems to be economically justifiable for selected agricultural applications, but careful design and matching of the solar system to the application needs are critical. System leaks, degradation of cover materials, and failures of sensors and controls are the three most important reliability problems.

Units: SI

Citation: Symposium, ASHRAE Transactions, 1987, vol. 93, pt. 2, Nashville, TN