This tool uses the percent value shown by the slider. Enter 20 for 20% moisture content. Internally, the wet-fuel equation converts that UI percent to MC=0.20.
まず、「HHVとLHVの値は燃料固有の絶対的なもの」という誤解があります。実は、同じ「木質チップ」でも樹種や部位、生育環境でHHVは変わります。ツールのデフォルト値は代表値なので、可能なら自社で使用する燃料の実測値(例えばJIS M 8814などに基づく発熱量測定)を入力すべきです。例えば、針葉樹と広葉樹ではHHVが1-2 MJ/kg程度異なることもあり、これが年間の燃料コスト計算に大きな影響を与えます。
Select an actual preset: wood chips, straw, MSW, sewage sludge, or custom.
Enter moisture content as a percent. Enter 20 for 20%; the code converts this to MC=0.20 internally.
Set efficiency, VS, and SMP. SMP is specific methane production in Nm3 CH4/kg-VS, so methane energy is not multiplied by 0.6 again.
Enter feedstock mass in kg. The tool updates LHV, useful energy, methane volume, biogas volume, and CO2 reduction.
Measured example
For 1,000 t/year of wood chips, enter 1,000,000 kg. With HHV=19.5 MJ/kg, H=6%, MC=35%, and boiler efficiency 78%, wet HHV=12.68 MJ/kg, wet LHV=10.96 MJ/kg, useful energy=8,551 GJ, and CO2 reduction=573 t-CO2. If methane yield is 200 Nm3/t, methane volume is 200,000 Nm3 and methane energy is 200,000*35.8/1000=7,160 GJ.
Notes
At HHV=19 and H=6%, each +5 percentage points of MC lowers LHV by about 1.01 MJ/kg; at HHV=15 the drop is about 0.81 MJ/kg.
At extreme moisture with low HHV, LHV can become negative. A negative CO2 result means net usable energy is negative, not carbon sequestration.
For biogas plants, apply a separate equipment/yield factor for retention time, temperature, and desulfurization losses.