Except for felled trees from civil engineering projects, the moisture content of residuals from wood utilization is considered to be 15% in dry base. Energy efficiency of direct burning as fuel chips is relatively high. There is also the possibility of gasification for electric power generation or for production of gas or liquid fuels. On the other hand, further consideration is necessary to utilize residuals from wood industries for energy production, because the moisture content may be nearly 100% in dry base and there are many types of residuals. Sawdust and bark, which requires little powdering energy, can be used as wood pellets.

The Japanese government is aiming to produce 2 million kL of bioethanol from wooden residuals by 2020. Lignin encloses cellulose etc. in the cell walls of wood, so saccharification

and fermentation are difficult without pre-processing. There is an opinion that automobiles

should be powered by electricity rather than liquid fuel in future.

Further information

Ministry of Land, Infrastructure and Transport Japan: Investigation of construction byproducts 2005(2006) (in Japanese)

Mayu Takagi, Hachiro Takeda, Takeshi Okano: Trends in the carbon transferred from forests to the populated area of Japan — Estimates from timber supply and demand statistics-, Wood Industry, 62(8), 354-357(2007) (in Japanese)

Mario Tonosaki, Yuko Tsunetsugu, Masayuki Ozawa, Kenji Hanaoka: Wood utilization for Japanese forestry, Journal of the Japan Institute of Energy, 84, 973-979(2005) (in Japanese)