自給可能な木質チップ利用の小型熱電併給事業による地域経済効果の推計

摘要

地方ではエネルギー代金の域外への支出が大きく，域内におけるエネルギー自給率を少しでも高めることが地方創生の1つの手段と認識されている。また，我が国の森林資源賦存量，あるいは蓄積量は非常に大きく，中山間地域などでは木質バイオマスの利用が期待されている。一方で，エネルギー用途の木質バイオマス（C材，D材） の集積は施業コストの面から難しい。製材や合板等に利用されるA材ゃB材といつた付加価値の高い木材の搬出基盤の上に燃料用のC，D材が集積される現実がある。地域において総合的な林業の底上げが無い限り，簡単には木質バイオマスを燃料利用できない。また，固定価格買取制度(FIT制度）を利用するための木質バイオマス量の確保は大いなる課題であり，輸入材が利用される事例も多い。%The revitalization of rural areas can be achieved by increasing the regional gross value added (RGVA). Among the options to revitalize Japan's rural economy, this study considered the option of operating a local business that can utilize local resources and investigated the economic effects. An input-output (IO) table for a small region was compiled and used to calculate RGVA as the regional consolidated profits. The plan was to set up a combined heat and power (CHP) plant of a suitable scale and utilize locally supplied wood biomass (about 450 t/year, 50% wet basis). The budget of the operation was assumed to be balanced (i.e., no profit) by setting the wood chip price at 16,830 yen/t (15% wet basis) under the Feed-in tariff scheme. Assumed direct investment (15.8 million yen) as the CHP operation would provide 8.4 million yen of the indirect effect and 9.4 million yen of RGVA, and the regional profits resulted from remedy of the local export/import balance. Concerning performance evaluation, a regional IO analysis can be conducted for effectively evaluating local businesses. Additionally, a regional consortium comprising public and private sectors can be established to manage operations that focus on improving the local trade balance, even its low profitability.