Design and evaluation of a low-cost solar kiln

A 500-BF solar kiln, with a built-in heat storage unit and a collector cover-reflector, was designed and built from readily available materials. The built-in heat storage unit was made of construction concrete blocks. The concrete blocks were stacked to form a solid right triangle with the slope parallel to the glazing panel. The slope side of the concrete blocks was painted black to act as an absorber as well as a heat exchanger. The collector cover-reflector was built from plywood and polyurethane board with an aluminum foil surface. During sunny days, the cover-reflector worked as a reflector. During rainy days and nights, it acted as a cover to keep the kiln from losing heat through the glazing panel. The total cost for instruments and materials was less than $2,000. This solar kiln dried 4/4 red oak lumber from green to 8 percent MC in 2 to 3 months, depending on the season. The dried wood quality was excellent, the drying stresses were mild, and drying defects were minimal. This type of solar kiln, with a built-in heat storage unit and a collector cover-reflector, offers an energy-efficient and economically attractive method to dry lumber for small sawmill managers, wood shop operators, and wood hobbyists.

You must be logged in to download any documents. Please login (login accounts are free) or learn how to Become a Member