Environmental Science & Policy 6 (2003) 533–541 Least cost electricity generation options based on environmental impact abatement Jerasorn Santisirisomboon a,b , Bundit Limmeechokchai a,∗ , Suparchart Chungpaibulpatana a a Sirindhorn International Institute of Technology, Thammasat University, P.O. Box 22 Thammasat Rangsit Post Office, Pathumthani 12121, Thailand b Faculty of engineering, Ramkhamhaeng University, Huamak, Bangkapi, Bangkok 10240, Thailand Abstract The power sector in Thailand is the largest contributor to CO 2 emissions. There is high potential to mitigate CO 2 emission via alternative power generating plants. Alternative plants considered in this study include nuclear plants, integrated gasification combined cycle plants, biomass-based plants and supercritical thermal power plants. The biomass-based plants considered here are fueled with four types of biomass; paddy husk, municipal solid waste (MSW), fuel wood and corncob. The methodology for the optimal expansion plan of the power generating system over the planning horizon is based on the least-cost approach. The results from the least-cost planning analyses show that the nuclear alternative has the highest potential to mitigate not only CO 2 but also other airborne emissions. Moreover, the nuclear option is the most effective abatement strategy for CO 2 reduction due to its negative incremental cost of CO 2 reduction. © 2003 Elsevier Ltd. All rights reserved. Keywords: Least cost electricity generation; Nuclear power; Biomass; Supercritical thermal power; Integrated gasification combined cycle; CO 2 mitigation 1. Introduction The power sector has an important implication for all countries economic development. It plays a critical role in energy consumption and environmental pollution emissions in Thailand. During the period 1990–1997, electricity de- mand increased at an average annual growth rate of 11.6% and the demand in 1997 was 82,431 GWh (DEDP, 1997). However, this high growth trend was considered unlikely to continue because of the economic recession in 1997. The electricity demands in 1998 and 1999 were 2.4 and 1.2% lower than the demand in 1997 (DEDP, 1999). The power industry, which has been built and operated under a “supply–follows–demand” philosophy, has always been able to fulfill its obligation by providing adequate and secure supplies of electricity at the lowest practicable cost. The objective of the power generation plan is to seek for the most economical generation expansion scheme to achieve a certain reliability level to meet the forecasted demand in- crease in a certain period of time. However, this has led to an onerous operating strategy requiring high plant margins and extensive environmental impacts on the range from the local to the global scale as it is a major energy consum- ∗ Corresponding author. Tel.: +662-986-9009x2206; fax: +662-986-9009x2501. E-mail address: bundit@siit.tu.ac.th (B. Limmeechokchai). ing sector and a large contributor of environmental pollu- tion emissions (especially CO 2 ). Based on the recent report of the Department of Energy Development and Promotion (DEDP), the power sector is the highest CO 2 emission sec- tor (DEDP, 1999). Thereby it has the highest potential to mitigate CO 2 emission significantly. There are many mechanisms for reducing CO 2 emissions from the power sector and one of the most practical mech- anisms is the switching from high- to less- or non-carbon intensive sources of generation (Hadley and Short, 2001). Four alternative power plants (including nuclear, integrated gasification combined cycle plants (IGCC), biomass and su- percritical plants) are considered for the mitigation of CO 2 emission in this study. The main objective of this study is to evaluate the most economical power generation expansion plan that not only meets the requirement of electricity demand, but also miti- gates CO 2 emission. The impacts of such alternatives on the primary energy supply are also assessed. 2. Final electricity and peak load demand projection The economic sector in Thailand comprises 5 sectors: agricultural, commercial, industrial, residential and trans- port. The electricity demand projection in these sectors was done by using the end-use model. The projected 1462-9011/$ – see front matter © 2003 Elsevier Ltd. All rights reserved. doi:10.1016/j.envsci.2003.08.004