Assessment of the Actual Performance of an Industrial Solar Kiln for Drying Timber

Abstract

The aim of this study was to assess the actual performance of an instrumented industrial solar kiln for drying Australian hardwood timber (Eucalyptus pilularis) boards (270 × 43 mm). Ambient temperature and humidity, air temperature and humidity in the kiln, and wood moisture contents were recorded on site (Heron's Creek, NSW, Australia) using sensors and an electronic data acquisition and logging system. The average increases in air temperatures in the kiln compared with ambient conditions were 17.3°C (May–June), 13.8°C (July–August), 10°C (September–October), 8.2°C (November–March), and 7.5°C (March–May) for five runs monitored. Drying times were 2–4 months from initial moisture contents of 43 to 62% (dry-basis) to final moisture contents of 12 to 22%. Overall, the solar kiln has been shown to be an acceptable alternative to air-drying for pre-drying of Australian hardwood timber.