Coal-fired power burn in the Electric Reliability Council of Texas totaled 7.3 TWh in May, up 53.5% from 4.8 TWh in April, according to ERCOT's latest Demand and Energy report, released on Friday.
Total energy rose 13.9% to 28.5 TWh in May, an increase of 3.5 TWh from a month earlier.
With the rise in coal-fired power burn outpacing growth in total electricity generation, coal rose to 25.6% of the overall fuel mix in May, up from 19% in April.
Nuclear generators posted the biggest decline month on month, dropping to a 9.5% share, from 14.6% in April.
Natural gas-fired generators remained the largest fuel source, supplying 13.6 TWh in May, up from 12 TWh in April.
Power supplied by wind farms totaled 4.7 TWh in May, up from 4.4 TWh in April.
Hourly demand peaked at 57,251 MW on May 10, up from April's peak of 50,920 MW on April 25.
