代用炭とは練炭、豆炭、炭団など木炭の代用品として使用された燃料の総称である。炭団は江戸時代から、練炭は明治中期、豆炭は大正中期に使われ始めた。代用炭需要の拡大は１９２０年代前半の木炭不足が契機となった。明治初年以来１９２０年に至るまで日本は大幅な木炭の輸出国であったが、１９２１年には輸入量が急増し、翌２２年には木炭輸入国となった。特に関東大震災が起こった１９２３年は前年の二倍の木炭を輸入・移入した。木炭生産量が増加していたことを考えると、需要の増加は都市化が原因であろう。
Substitute coal is a collective term of fuels replaced and used by wood coal such as artificial coal, pea coal and coal field. People started using coal field from Edo era, artificial coal in the middle of Meiji era and pea coal in the middle of Taisho era.
The expansion of substitute coal's demand was caused by the shortage of wood coal in the early 1920's.
From the early times of Meiji era to 1920, Japan was a major exporter of wood coal, but the amount of import increased in 1921, Japan became an importer of wood coal on the following year 1922. Especially when the Great Kanto Earthquake struck in 1923, the amount of wood coal imported doubled.
Given the volume of production increased then, the increased demand could be attributed to urbanization.
