By: Aaron Larson |
The Electric Reliability Council of Texas (ERCOT) completed an evaluation of a plan to export power to Mexico from the Frontera Generation Station, located in Mission, Texas.
Although the results indicated that the power system could operate effectively during normal conditions without Frontera’s capacity, ERCOT says it has concerns with power supply sufficiency and transmission stability when demand is high or other facilities serving the region are not available.
Frontera is a combined cycle natural gas–fired plant that was built in 1999–2000. It is capable of sending power to either ERCOT or Mexico. On May 22, Frontera Generation and Lonestar Power Marketing filed a joint application with the Department of Energy (DOE) to transfer the authority to transmit electric energy from the U.S. to Mexico. According to ERCOT, the intention is for the plant to send 170-MW of generation across the border in 2015, and to increase exports to the plant’s full 524-MW capacity in 2016.
The Lower Rio Grande Valley Development Council says the area is one of the fastest growing regions in the U.S. Residents have faced transmission emergencies, requiring rotating outages, as recently as Oct. 8. At the time, ERCOT instructed transmission and distribution companies to reduce system demand in the Valley by 200 MW as a result of unplanned power plant outages and system limitations in the region. The following day, ERCOT resorted to a conservation appeal to prevent further outages when an unrelated issue with a high-voltage transmission line serving the area arose.
Two large transmission projects—totaling about $1 billion in improvements—are underway to enable more electricity to flow into the region by mid-2016. The Lower Rio Grande Valley project will upgrade and increase capacity of facilities that import power from the Corpus Christi area and will provide a new circuit into the Valley from the Laredo area. The Cross Valley project will provide a new circuit connecting facilities in Hidalgo County to the facilities at the Brownsville Ship Channel.
Until those projects are done, the ERCOT study identified potential concerns if power from the Frontera plant is unavailable during emergency situations. As a result, ERCOT and Frontera’s owners have agreed on the reliability safeguards needed to ensure the plant will be available, if needed, and filed those conditions with the DOE as part of the plant’s export authorization.