Gas' share of ERCOT January fuel mix rises, gap to coal tops 10%

Houston (Platts)--7 Feb 2018 651 pm EST/2351 GMT

Natural gas remained the feedstock of choice for electricity generation in the Electric Reliability Council of Texas in January, exceeding coal's share by a wider margin than in December, as an extremely cold spell and higher-than-expected peakload demand called on more gas peakers, according to data from the grid operator.

Gas-fired generation accounted for 12.1 TWh or about 39% of total energy supply in January, compared with about 38% in December and its highest share since September, when gas units contributed more than 41% of supply.

ERCOT data showed coal-fired generation produced 8.9 TWh in January, or about 28% of the fuel mix, compared with a 33% share in December and 36% a year earlier.

The difference between gas and coal's share of the fuel mix topped 10% in January, compared with 5% in December, was the highest since August, when gas accounted for half of total generation output and serve peak summer cooling loads.

Heating degree days in Texas totaled 562 in January, 28 above normal and 217 above the year-ago level, according to US National Weather Service data.

The grid operator set a peakload record for both January and the winter months, topping 65.7 GW on January 17, 17% above the forecast peakload for the month and 10% above the year-ago level.

Energy usage also turned out to be higher than expected, totaling 31 TWh in January, about 7% higher than forecasts and 14% higher than last year.

Higher spot gas prices did not seem to cap gas-fired power burn, as spot gas prices at Houston Ship Channel averaged above $4/MMBtu in January, about 47% higher than December's average and around 26% above the year-ago level.

Wind generation also saw a strong start to the year, following robust growth in 2017, as wind output accounted for almost 20% of total generation in January, up from 16.4% in December and 19.8% a year earlier.

ERCOT also set an hourly wind output record of 17.4 GW on January 11, accounting for over 43% of total load at the time.

The latest ERCOT data show wind generation resources installed across its footprint totaled more than 20 GW at the end of January, and another 3.9 GW is expected to be added by the end of 2018.

Nuclear output ticked down to about 12% of total supply in January from 13% in December and around 14% in January 2017.

--Jeff Zhou,

--Edited by Keiron Greenhalgh,

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