Xcel's Southwestern Public Service coal mix rises to 26.9% in July: filing

Houston — Southwestern Public Service Company's coal generation mix rose to 26.9% in July, while its natural gas/oil mix rose to 29.5%, according to a company filing with state regulators.

The utility, a subsidiary of Xcel Energy, told the Public Utility Commission of Texas it burned over $14.84 million worth of Powder River Basin coal in July at its 1,018-MW Harrington coal-fired power plant in Amarillo and its 1,067-MW Tolk Station in Muleshoe, up from $7.59 million worth of coal burned in June, which made up 15.5% of the generation mix.

In the year-ago month, the utility burned nearly $9.88 million worth of coal at a 63.2% capacity factor, resulting in a 22.6% generation mix.

The two plants generated 793,707 MWh of power in July, or 8.67 million MMBtu, while operating at a 51.2% capacity factor. The company's six gas/oil plants generated 872,610 MWh of power, or 10.16 million MMBtu, at a 49.6% capacity factor.

On a cost per MMBtu basis, the coal plants were at $1.71/MMBtu in July, and the gas plants were at $1.58/MMBtu, while the average dispatch price for coal was $18.70/MWh, compared with $18.36/MWh for gas/oil. Coal's dispatch price was $19.57/MWh in June and $18.14/MWh in July 2019.

In July, Southwestern Public Service bought 483,592 st of 8,825 Btu/lb coal from Tuco, Inc., a coal supplier, up from 242,730 st in June and 389,603 st in the year-ago month. About 282,649 st of coal went to the Harrington plant in July, while the remaining 200,943 st went to the Tolk Station.

On an MMBtu basis, the company bought over 8.57 million MMBtu of coal in July, while gas purchases totaled 10.26 million MMBtu.

In 2019, Southwestern Public Service bought 4.03 million st of 8,875 Btu/lb PRB coal at an average delivered cost of $30.32/st, according to data from the US Energy Information Administration. The Harrington plant took delivery of 2.36 million st at an average price of $28.35/st, while 1.67 million st was shipped to the Tolk Station at $32.29/st.

About 86% of the coal supplied by Tuco came from the Black Thunder mine, while the remaining 14% was from the North Antelope Rochelle mine, which are both located in Campbell County, Wyoming, according to the data.

Southwestern Public Service Company serves 400,000 electric customers in Texas and New Mexico.