This paper evaluates the practical applicability of induced technologiesutilizing renewable energy (hereafter renewable technologies) and attempts tofind new cost-effective paths to reduce greenhouse gas in the presence ofrenewable technologies. For these purposes, we build a fully dynamic CGEmodel, in which intertemporal emission trading is possible and renewabletechnologies are determined endogenously. This paper shows that renewabletechnologies can reduce GDP loss and lower emission trading priceconsiderably. However, since the spread of renewable technologies will growfaster over time and, as a result, the future reduction cost will become lowerthan the present reduction cost, the national reduction target should be set inaccordance with the diffusion level of renewable technologies. According tothis optimal reduction path, the Korean national greenhouse gas reductiontarget should be adjusted down from 30% to 25% for 2020, and up from 50%to 60% for 2050. Throughout these adjustments of the national reductiontarget, we expect smaller GDP loss by 0.3%p a year on the average.