In Shunan City, Yamaguchi Prefecture (May 2003), a regional circulation agriculture project utilized livestock waste and crop residues for biogas power generation. The electricity supplied local needs, while the digestate was returned to farmland as fertilizer. This reduced waste, promoted resource recycling, mitigated odors, and prevented river pollution.

In Shunan City, Yamaguchi Prefecture (May 2003), a regional circulation agriculture project utilized livestock waste and crop residues for biogas power generation. The electricity supplied local needs, while the digestate was returned to farmland as fertilizer. This reduced waste, promoted resource recycling, mitigated odors, and prevented river pollution.