Renewable Electricity Expenses
Operating and maintenance expenses for our Renewable Electricity facilities in the first nine months of 2022 were $9,204, an increase of $378 (4.3%) compared to $8,826 in the first nine months of 2021. The increase is primarily related to operating expenses related to Montauk Ag Renewables Acquisition.
Royalties, transportation, gathering and production fuel expenses for our Renewable Electricity facilities for the first nine months of 2022 were $1,342, an increase of $38 (2.9%) compared to $1,304 in the first nine months of 2021. As a percentage of Renewable Electricity Generation segment revenues, royalties, transportation, gathering and production fuel expenses decreased to 10.6% from 11.5%.
Royalty Payments
Royalties, transportation, gathering, and production fuel expenses in the first nine months of 2022 were $34,484, an increase of $15,644 (83.0%) compared to $18,840 in the first nine months of 2021. We make royalty payments to our fuel supply site partners on the commodities we produce and the associated Environmental Attributes. These royalty payments are typically structured as a percentage of revenue subject to a cap, with fixed minimum payments when Environmental Attribute prices fall below a defined threshold. To the extent commodity and Environmental Attributes’ prices fluctuate, our royalty payments may fluctuate upon renewal or extension of a fuel supply agreement or in connection with new projects. Our fuel supply agreements are typically structured as 20-year contracts, providing long-term visibility into the margin impact of future royalty payments.
Depreciation
Depreciation and amortization in the first nine months of 2022 was $15,453, a decrease of $1,609 (9.4%) compared to $17,062 in the first nine months of 2021. The decrease is associated with assets remaining in service being fully amortized and depleted.
Impairment loss
We calculated and recorded an impairment loss of $2,393 in the first nine months of 2022, an increase of $1,767 (282.3%) compared to $626 in the first nine months of 2021. The impairment loss recorded in the first nine months of 2022 was primarily related to an REG facility where forecasted cash flows did not exceed the carrying value of the long-lived assets.
Other (Income) Expenses
Other income in the first nine months of 2022 was $124, an increase of $2,850 (104.5%) compared to other expenses of $2,726 in the first nine months of 2021. Of the increase, $1,725 is related to our favorable interest rate swap contract resulting in reduction of interest expense from the first nine months of 2022 compared to the first nine months of 2021. Also impacting the increase is $865 relating to asset disposal costs at our Galveston and Pico facilities in the first nine months of 2021.
Income Tax Expense
Income tax expense for the nine months ended September 30, 2022 was calculated using an estimated effective tax rate which differs from the U.S. federal statutory rate of 21% primarily due to the adjustment for production tax credits.
The effective tax rate of 19.0% for the nine months ended September 30, 2022 was higher than the rate for the nine months ended September 30, 2021 of (14.7%) primarily due to current period pre-tax income increases used to complete the effective tax rate calculation and a required Code Section 162(m) executive compensation limitation permanent adjustment. The September 30, 2022 rate also includes utilization of production tax credits and certain discrete items.
Operating Profit for the Nine Months Ended September 30, 2022 and 2021
Operating profit in the first nine months of 2022 was $35,947, an increase of $41,956 (698.2%) compared to an operating loss of $6,009 in the first nine months of 2021. RNG operating profit for the first nine months of 2022 was $75,040, an increase of $40,886 (119.7%) compared to $34,154 in the first nine months of 2021. Renewable Electricity Generation operating loss for the first nine months of 2022 was $4,226, a decrease of $600 (16.5%) compared to an operating loss of $3,626 for the first nine months of 2021.
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