MARIETTA — A $4.3 million write-off related to Power4Georgians and a demand from Uncle Sam for $1.7 million in back taxes helped push Cobb EMC’s expenses higher than revenue in the third quarter, which ended Jan. 31.

The Marietta-based electric membership cooperative reported a loss of $2,832,561 on revenues of $115,982,756 and expenses of $118,815,317 for the quarter.

Year-to-date, the company reports a total profit of $13,509,729. In all of fiscal year 2011, the company saw almost $22 million in profits, but executives anticipate less this year.

As for the third-quarter revenue, income from natural gas marketer Gas South, a wholly owned subsidiary of the cooperative, accounted for 45 percent of the $115.9 million in revenue and 34 percent of the quarter’s expenses.

“Gas South had a good quarter in spite of very mild winter temperatures,” said Robert Steele, the company’s chief financial officer.

The corporation also wrote off half of its non-land investment in the Power4Georgians consortium, which aims to build the coal-fired Plant Washington. On Jan. 24, the Cobb EMC directors voted 7-2 to stop funding P4G. The company has already spent $13.5 million with P4G, and wrote off $4,306,045 of that this quarter.

Cobb EMC also paid the IRS $1.5 million for additional tax and $220,060 in interest for tax year 2008 this quarter. The IRS audited the corporation’s 2008 and 2009 consolidated tax returns and settled the audits on Dec. 9. No additional taxes were owed for 2009.

For tax year 2012, the corporation will begin filing separate tax returns for Cobb EMC and Gas South. The change is expected to allow Cobb EMC to meet the 85/15 test — meaning 85 percent of EMC’s revenue must be member-generated — to regain its exemption from federal and state income taxes. Still, Steele said it won’t affect the company’s bottom line.

“There will be virtually no dollar savings for Cobb EMC returning to tax-exempt status,” Steele said. “The taxes owed were related to Gas South activity.”

As for the company’s overall bottom line when fiscal 2012 ends on April 30, Steele predicted it will be $4 million to $5 million lower than the nearly $22 million made in FY 2011 because of warm temperatures throughout much of the year.

Cobb EMC has more than 170,000 meters and serves residential and commercial customers in Cobb, Paulding, Bartow and Cherokee counties in metro Atlanta and Randolph, Quitman, Calhoun and Clay counties in south Georgia.