Using market-based dispatching with environmental price signals to reduce emissions and water use at power plants in the Texas grid

• Main Authors: Alhajeri, Nawaf S. (Author), Donohoo, Pearl E. (Contributor), Stillwell, Ashlynn S. (Author), King, Cary W. (Author), Webster, Mort David (Contributor), Webber, Michael E. (Author), Allen, David T. (Author)
• Other Authors: Massachusetts Institute of Technology. Engineering Systems Division (Contributor)
• Format: Article
• Language: English
• Published: Institute of Physics Publishing, 2012-04-13T16:08:33Z.
• Subjects: Article
• Online Access: Get fulltext

 The possibility of using electricity dispatching strategies to achieve a 50% nitrogen oxide (NOx) emission reduction from electricity generating units was examined using the grid of the Electricity Reliability Council of Texas as a case study. Simulations of a hypothetical policy demonstrate that imposing higher NOx prices induces a switch from some coal-fired generation to natural gas generation, lowering NOx emissions. The simulation is for a day with relatively high electricity demand and accounts for transmission constraints. In addition to the lowering of the NOx emissions, there are co-benefits of the redispatching of generation from coal to natural gas, including reductions in the emissions of sulfur oxides (24%-71%), Hg (16%-82%) and CO2 (8.8%-22%). Water consumption was also decreased, by 4.4%-8.7%. Substantial reductions of NOx emissions can be achieved for an increased generation cost of 4-13%, which is due to the higher fuel price of gas relative to coal (assuming a price of $3.87 per MMBTU (MMBTU: million British thermal units) for natural gas, and $1.89 per MMBTU for coal). However, once the system has reduced NOx emissions by approximately 50%, there is little incremental reduction in emissions due to further increases in NOx prices.