Study on The Development and Economic Evaluation of Solar Drying System for Wood Industry

목재산업용(木材産業用) 태양열(太陽熱) 건조장치(乾燥裝置)의 개발(開發)과 경제성분석(經濟性分析)에 관한 연구(硏究)

Experimental external collector type solar lumber dryer of $1m^3$ of maximum capacity with $1.6m^3$ of collector area was designed and constructed. The seasonal performance of solar dryer, including air-conditions, energy efficiency, and drying characteristics of 3cm-thick red pine and douglas-fir lumber was investigated. Also, the economic analysis was carried out. Annual average solar drying rate was about 2 times faster than air-drying rate with no significant difference in the amount of drying defects. But in initial drying stage air-drying rate in winter was much faster and those in spring and autumn were slightly slower than solar drying rate in each season. Annual average energy efficiency of solar-dryer and-collector was 25% and 57%, respectively. Fuel savings were over 50% at 15% of energy inflation rate and the payback period was estimated as 6.10 years at 30% of energy inflation rate.