Environmental and economic assessment of landfill gas electricity generation in Korea using LEAP model

As a measure to establish a climate-friendly energy system, Korean government has proposed to expand landfill gas (LFG) electricity generation capacity. The purpose of this paper is to analyze the impacts of LFG electricity generation on the energy market, the cost of generating electricity and greenhouse gases emissions in Korea using a computer-based software tool called 'Long-range Energy Alternative Planning system' (LEAP) and the associated 'Technology and Environmental Database'. In order to compare LFG electricity generation with existing other generating facilities, business as usual scenario of existing power plants was surveyed, and then alternative scenario investigations were performed using LEAP model. Different alternative scenarios were considered, namely the base case with existing electricity facilities, technological improvement of gas engine and LFG maximum utilization potential with different options of gas engine (GE), gas turbine (GT), and steam turbine (ST). In the technological improvement scenario, there will be 2.86 GWh or more increase in electricity output, decrease of 45 million won (Exchange rate (1$=1200 won)). in costs, and increase of 10.3 thousand ton of CO₂ in global warming potentials due to same period (5 year) of technological improvement. In the maximum utilization potential scenario, LFG electricity generation technology is substituted for coal steam, nuclear, and combined cycle process. Annual cost per electricity product of LFG electricity facilities (GE 58MW, GT 53.5MW, and ST 54.5MW) are 45.1, 34.3, and 24.4 won/kWh, and steam turbine process is cost-saving. LFG-utilization with other forms of energy utilization reduces global warming potential by maximum 75% with compared to spontaneous emission of CH₄. LFG electricity generation would be the good solution for CO₂ displacement over the medium term and additional energy profits.