Japan’s forestry reserve in FY2005 was 4,340 million m³, composed of planted forests (2,554 million m³) that are cultured by human hands for producing lumber, and natural forests (1,786 million m³) that are grown by the Nature.

The forestry reserve has been increasing steadily at a pace of 80 million m³ a year, of which planted forests have larger proportion. This is on one hand because the trees planted just after the World War II, by national encouragement policy, have now grown up and waiting for cutting down, and on another hand because comparatively low-priced imported lumber increased and consequently use of domestic wood became very little.

A huge amount of woody biomass, as waste, is generated every year in Japan’s forest reserve. It is composed of forestry residue (8.6 million m³), waste from lumber mills (10.8 million m³), and waste from construction (11.8 million m³).
Regarding use of the woody biomass, 8.6 million m³ (28 %) is used for energy generation, 9.8 million m³ (31 %) is used for production of various materials, and so far, Japan could not find a proper way to reuse the rest 12.8 million m³ (41 %).

Suppose that all of the unused woody biomass as much as 12.8 million m³ to be palletized and used for energy generation, the total energy will be equal to that of 2.4 million kl of crude oil, and in addition it will result in the reduction of CO2 emission by 5 million ton. Considering of the unused biomass as well as the abovementioned natural increase of forest reserve as much as 80 million m³ per year, Japan has indeed a very abundant, unused woody biomass resources. If it is possible to use them properly as energy resources, Japan could cut down CO2 emission drastically.

As for a new way of woody biomass use, on 2 June 2010, IDEX Co,LTD made an announcement that it would start construction of a hydrogen gas production plant that gasifies woody biomass. The plant, reportedly, would use various waste woody biomasses discharged from lumber mills and construction sites in Fukuoka prefecture, and it can produce 7,200m³ of high purity hydrogen gas per day from 15 ton of waste woody biomasses. IDEX Co,LTD plans to make test run of the plant during FY 2011 before starting full commercial operation. A commercial type gasification plant of this scale (15 ton/day) is the first in the world. The hydrogen produced here will be used for fuel-cells.

Table  Forestry Reserve of Japan (Unit: million cubic meter)

Fiscal. Year	1969	1976	1986	1995	2002	2005
Forest Kind
Planted	558	798	1,361	1,892	2,338	2,554
Natural	1,329	1,388	1,502	1,591	1,702	1,786
Total	1,887	2,186	2,863	3,483	4,040	4,340

 

Fig.  Record of Forestry Reserve of Japan

 

Fig.  Waste Woody Biomass and Ways of Reuse

 

Source:
1) “Challenges in Forestry and Lumber Industries”, June 2008, Forestry Agency,
2) a press release of IDEX Co,LTD
3) “Energy Use of Woody Biomass”, 2006, National Library No.510
et al