Net CO2 of Imported Wood Pellet Electricity in South Korea: A Time-Horizon Model

Electricity from imported wood pellets in South Korea emits 219 kg CO2 per MWh from the supply chain and 1222 kg per MWh as biogenic CO2 at the stack, against 910 kg for coal and 367 kg for natural gas (combustion only). This study builds a per-MWh model with IPCC emission factors and supply-chain values from the literature, and treats the re-absorption of the biogenic CO2 by the forest as a time-dependent assumption. With one regrowth time for all pellets (5, 30, 60 or 100 years), pellet electricity emits less than coal after about 2, 13, 26 or 43 years. With a regrowth time per supplier (6 years for plantation pellets from Vietnam and Indonesia, 70 years for Canada, 100 years assumed for Russia), break-even with coal is about 3 years for Vietnam and Indonesia, 32 years for Canada and 42 years for Russia, and about 4 years for the import-weighted mix. Regrowth time and plant efficiency change the result most; the transport distance (1000 to 9500 km of sea transport) changes it by only 1 to 4 years. The results are modelled estimates built on simplifying assumptions and are not validated against plant data.