| Parameter | Value | Unit |
|---|---|---|
| HHV (dry basis) | — | MJ/kg |
| HHV (wet basis) | — | MJ/kg |
| LHV (wet basis) | — | MJ/kg |
| LHV (kWh equiv.) | — | kWh/kg |
| Effective heat (combustion) | — | GJ/batch |
| Power generation est. (35%) | — | kWh |
| Biogas yield | — | Nm³ |
| Methane yield | — | Nm³ |
| Fossil fuel CO2 reduction | — | t-CO2 |
Theory Notes
HHV to LHV conversion:
$$\text{LHV}_{\text{wet}} = \text{HHV}_{\text{dry}} \times (1-\text{MC}) - 2.442 \times \left(\frac{9H}{100}(1-\text{MC}) + \text{MC}\right)$$Biogas energy:
$$E_{\text{biogas}} = m \times \frac{\text{VS}}{100} \times \text{SMP} \times 0.6 \times 35.8 \text{ (MJ/Nm}^3\text{)}$$The factor 0.6 is the typical methane volume fraction in biogas (60%). CO2 reduction is compared against heavy oil (40 MJ/kg, 2.68 kg-CO2/kg).
Engineer Dialogue — "Why are there two heating values?"
🧑🎓 "HHV and LHV are both called heating values — why do we need two numbers?"
🎓 "When you burn hydrogen in a fuel, you get water vapor. HHV assumes that steam condenses back to liquid and you capture all that latent heat. LHV assumes the steam leaves as vapor — so it's a lower number."
🧑🎓 "So HHV is always bigger. Which one should I actually use?"
🎓 "For gas turbines, engines, and most industrial furnaces, use LHV — the exhaust leaves hot and you don't recover condensation. Condensing boilers can exceed 100% LHV efficiency by recovering that latent heat. In Europe and Japan, LHV is the standard for combustion design."
🧑🎓 "And with biomass, the moisture makes things worse?"
🎓 "Exactly. At MC = 50% you're spending a lot of energy just evaporating water before you get useful heat. That's why biomass power plants invest heavily in drying systems and monitor incoming chip moisture in real time."