Gulf Power saw coal-fired units' share of its generation mix fall to 33.2% in August from 39.6% in July and 42.9% in the year-ago month, according to a state regulatory filing.
Coal burn totaled 129,285 st in August, which generated 218,874 MWh of power, down from 178,992 st in July and 302,636 MWh. The burn total also fell from 161,204 st, or 300,765 MWh, in the year-ago month, according to a filing published Sept. 22 by the Florida Public Service Commission.
Natural gas-fired units' slice of the stack came in at 64.7%, or 564,555 MWh, in August, up from 58.3% in July and 56.9% in the year-ago month.
In August, Gulf Power's average fuel cost for coal was $59.54/st, down from $64.22/st in July and $66.52/st in the year-ago month.
The heat rate efficiency for the coal units was at 10,605 Btu/kWh in August, while the gas units' was 8,195 Btu/kWh, resulting in dispatch prices of roughly $34.70/MWh and $23.60/MWh, respectively. In July, the coal units' dispatch price was $37.20/MWh and their gas counterparts' was $19.50/MWh, while in the year-ago month, coal came in at $35.40/MWh and gas at $23.10/MWh.
Through the first eight months of 2020, the utility has burned 820,495 st of coal, down from 1.3 million st in the year-ago period. Since the start of the year, coal's cumulative share of the generation stack was 29% and gas took a 68.7% share of the pie, compared with 53.5% and 46.2%, respectively, in the year-ago period.
Gulf Power owns the Crist coal-fired power plant in Pensacola, Florida, as well as a 50% stake in Mississippi Power's Daniel plant in Escatawpa, Mississippi and a 25% stake in one generating unit at Georgia Power's Scherer plant in Juliette, Georgia.
Coal purchases decline on month
Excluding the Scherer plant, Gulf Power purchased 89,581 st of coal in August at an average price of $57.02/st, down from 113,531 st at $64.40/st in July and 184,885 st at $66.89/st in the year-ago month.
The utility also bought $461,887 worth of coal for the Scherer plant in August at an average cost of $3.31/MMBtu, compared with $508,272 worth of coal at $3.46/MMBtu in July and $948,899 worth at $2.72/MMBtu in the year-ago month.
At the end of August, Gulf Power's coal stockpile, excluding the Scherer plant, was 317,496 st, or 20 days of cover, compared with 357,200 st, or 22 days cover at the end of July, and 423,880 st, or 27 days cover, at the end of August 2019.
The Scherer plant had 43 days of supply at the end of August, down from 56 days at the end of July and 33 days at the end of the year-ago month.
