Sustainability Assessment of Gas-Fired Power Generation Pathways

Quantitative indicators are essential tools in the sustainability assessment process of power generation from different fuel-based pathways. A comprehensive assessment must combine all the sensitive sustainability factors related to natural resource use, environmental impacts, and economic issues. This paper is intended to establish measurable indicators for the sustainability of gas-fired power generation pathways. Thirty-nine pathways were structured based on the full life cycle assessment, including gas extraction, power generation technology, and the cooling systems unit operations. The developed sustainability indicators include water demand, greenhouse gas (GHG) emissions, land use, and the levelized cost of electricity (LCOE). Cogeneration pathways are the most sustainable technology compared to the other gas-fired power generation technologies. Dry cooling on the power plant combined with cogeneration technology outperforms the different pathways towards greater sustainability. The cooling system, combustion of natural gas, conversion efficiency, and pipeline transportation are the sensitive factors for water demand, GHG emissions, LCOE, and land use indicators, respectively. A multi-objective sustainability scenario was conducted to cover a demand with an installed capacity range of 250 MW - 5000 MW. The constraints were adjusted with the minimum possible LCOE and the lowest potential quantitative impacts on natural resources and GHG emissions. When importing natural gas from a different jurisdiction in the sustainability scenario and based on the average values, 97% of the land area was saved. GHG emissions were mitigated by 15%, which increased the average LCOE by 15%.