Uses for expanded production of natural gas liquids: chemicals or power?

摘要

Expanded production of natural gas liquids (NGLs, ethane, propane, butanes) inrnthe United States may continue to be utilized in domestic and internationalrnchemical manufacturing; however, this would require the development ofrnexpanded transport infrastructures. Electricity generation is an alternative usernfor NGLs. As a case study of the value of NGLs in electricity generation, thernpotential use of NGLs in the Texas electrical grid was evaluated. It was assumedrnthat electricity would be generated in 25-MW gas turbines, located at gasprocessingrnplants where NGLs in produced gas are separated to create pipelinequalityrngas. The potential magnitude of NGL-based power generation in thernTexas grid, using NGLs produced in the Eagle Ford and Barnett oil and gas productionrnregions in Texas, was estimated to be up to 2.7 GW of electricity, 6% ofrnaverage demand on the grid. The NGL-based electricity generation displacedrncoal and natural gas-based generation, with little impact on the use of renewables.rnAt the assumed efficiency (34.7%) and nonfuel operating cost ($7/MWh) ofrnsmall gas turbines, NGLs are only fully utilized for electricity generation in thernTexas grid when fuel prices are lower than $1.50 per million BTU (a discount ofrn$0.90 per million BTU relative to the fuel price of coal assumed in the modeling).rnHigher prices might be supported if NGLs are used for electricity generation atrntimes of high demand or if larger, higher efficiency turbines are utilized.