Energy and Carbon Dioxide Emission Analysis of Straw-Based Power Plants

There has been a rapid growth in using straw as an energy source to generate electricity in China. The energy efficiency is important as a measure of the sustainability of such an activity, while the CO2 emitted and that saved by substituting conventional electricity are also important. The primary energy (PE) input and CO2 emission performance of three kinds of straw-based power plants have been evaluated in this study. The PE input of 5.5 MW gasification system (204 MJ/MWh) under the specific conditions are found to be the smallest, followed by that of 25 MW direct-fired system (276 MJ/MWh) and 1 MW gasification system (305 MJ/MWh). Consequently, the CO2 emission per unit electricity produced is lowest for the 5.5 MW gasification system (18 kg/MWh), followed by the 25 MW direct-fired system (24 kg/MWh) and the 1 MW gasification system (26 kg/MWh). Fuel consumption of straw delivery is the main contributor. For 5.5 MW gasification system, the most important activity is transportation while for the other two systems the most important activity is chopping. Straw-based electricity could be a feasible alternative for clean energy