We recognize revenue when our performance obligations under contracts with customers have been satisfied, which generally occurs when our businesses have delivered or transported natural gas, electricity or propane to customers. We exclude sales

taxes and other similar taxes from the transaction price. Typically, our customers pay for the goods and/or services we provide in the month following the satisfaction of our performance obligation. The following table displays revenue by major source based on product and service type for the years ended December 31, 2023, 2022 and 2021:


	For the year ended December 31, 2023
(in thousands)	Regulated Energy		Unregulated Energy		Other and Eliminations		Total
Energy distribution
Delaware natural gas division	$	83,882	$	—	$	—	$	83,882
Florida Natural Gas distribution (1)	168,360		—		—		168,360
Florida City Gas (2)	12,073		—		—		12,073
FPU electric distribution	99,474		—		—		99,474
Maryland natural gas division	28,092		—		—		28,092
Sandpiper natural gas/propane operations	20,185		—		—		20,185
Elkton Gas	8,814		—		—		8,814
Total energy distribution	420,880		—		—		420,880

Energy transmission
Aspire Energy	—		37,139		—		37,139
Aspire Energy Express	1,478		—		—		1,478
Eastern Shore	79,923		—		—		79,923
Peninsula Pipeline	30,400		—		—		30,400
Total energy transmission	111,801		37,139		—		148,940

Energy generation
Eight Flags	—		19,207		—		19,207

Propane operations
Propane distribution operations	—		154,748		—		154,748

Compressed Natural Gas Services
Marlin Gas Services	—		12,300		—		12,300

Other and eliminations
Eliminations	(59,086)		(246)		(26,321)		(85,653)
Other	—		—		182		182
Total other and eliminations	(59,086)		(246)		(26,139)		(85,471)

Total operating revenues (3)	$	473,595	$	223,148	$	(26,139)	$	670,604

(1) In accordance with the Florida PSC approval of our natural gas base rate proceeding, effective March 1, 2023, our natural gas distribution businesses in Florida (FPU, FPU-Indiantown division, FPU-Fort Meade division and Chesapeake Utilities' CFG division) have been consolidated and amounts above are now being presented on a consolidated basis consistent with the final rate order.

(2) Operating revenues for FCG include amounts from the acquisition date through December 31, 2023. For additional information on FCG's results, see Note 4, Acquisitions, and discussion under Item 7, Management's Discussion and Analysis of Financial Condition and Results of Operations.

(3) Total operating revenues for the year ended December 31, 2023, include other revenue (revenues from sources other than contracts with customers) of $1.2 million and $0.4 million for our Regulated and Unregulated Energy segments, respectively. The sources of other revenues include revenue from alternative revenue programs related to revenue normalization for Maryland division and Sandpiper and late fees.


	For the year ended December 31, 2022
(in thousands)	Regulated Energy		Unregulated Energy		Other and Eliminations		Total
Energy distribution
Delaware natural gas division	$	82,176	$	—	$	—	$	82,176
Florida Natural Gas distribution (1)	155,870		—		—		155,870
FPU electric distribution	81,714		—		—		81,714
Maryland natural gas division	26,607		—		—		26,607
Sandpiper natural gas/propane operations	21,278		—		—		21,278
Elkton Gas	9,198		—		—		9,198
Total energy distribution	376,843		—		—		376,843

Energy transmission
Aspire Energy	—		56,225		—		56,225
Aspire Energy Express	1,377		—		—		1,377
Eastern Shore	78,624		—		—		78,624
Peninsula Pipeline	27,263		—		—		27,263
Total energy transmission	107,264		56,225		—		163,489

Energy generation
Eight Flags	—		25,318		—		25,318

Propane operations
Propane distribution operations	—		188,412		—		188,412

Compressed Natural Gas Services
Marlin Gas Services	—		11,159		—		11,159

Other and eliminations
Eliminations	(54,683)		(364)		(29,778)		(84,825)
Other	—		—		308		308
Total other and eliminations	(54,683)		(364)		(29,470)		(84,517)

Total operating revenues (2)	$	429,424	$	280,750	$	(29,470)	$	680,704

(2) Total operating revenues for the year ended December 31, 2022, include other revenue (revenues from sources other than contracts with customers) of $0.5 million and $0.4 million for our Regulated and Unregulated Energy segments, respectively. The sources of other revenues include revenue from alternative revenue programs related to revenue normalization for Maryland division and Sandpiper and late fees.


	For the year ended December 31, 2021
(in thousands)	Regulated Energy		Unregulated Energy		Other and Eliminations		Total
Energy distribution
Delaware natural gas division	$	71,195	$	—	$	—	$	71,195
Florida Natural Gas distribution (1)	134,609		—		—		134,609
FPU electric distribution	78,300		—		—		78,300
Maryland natural gas division	22,449		—		—		22,449
Sandpiper natural gas/propane operations	20,746		—		—		20,746
Elkton Gas	7,105		—		—		7,105
Total energy distribution	334,404		—		—		334,404

Energy transmission
Aspire Energy	—		38,163		—		38,163
Aspire Energy Express	187		—		—		187
Eastern Shore	76,911		—		—		76,911
Peninsula Pipeline	26,630		—		—		26,630
Total energy transmission	103,728		38,163		—		141,891

Energy generation
Eight Flags	—		18,652		—		18,652

Propane operations
Propane distribution operations	—		142,082		—		142,082

Compressed Natural Gas Services
Marlin Gas Services	—		8,315		—		8,315

Other and eliminations
Eliminations	(54,212)		(343)		(21,348)		(75,903)
Other	—		—		527		527
Total other and eliminations	(54,212)		(343)		(20,821)		(75,376)

Total operating revenues (2)	$	383,920	$	206,869	$	(20,821)	$	569,968

(2) Total operating revenues for the year ended December 31, 2021, include other revenue (revenues from sources other than contracts with customers) of $0.2 million and $0.4 million for our Regulated and Unregulated Energy segments, respectively. The sources of other revenues include revenue from alternative revenue programs related to revenue normalization for Maryland division and Sandpiper and late fees.

Our energy distribution operations deliver natural gas or electricity to customers, and we bill the customers for both the delivery of natural gas or electricity and the related commodity, where applicable. In most jurisdictions, our customers are also required to purchase the commodity from us, although certain customers in some jurisdictions may purchase the commodity from a third-party retailer (in which case we provide delivery service only). We consider the delivery of natural gas or electricity and/or the related commodity sale as one performance obligation because the commodity and its delivery are highly interrelated with two-way dependency on one another. Our performance obligation is satisfied over time as natural gas or electricity is delivered and consumed by the customer. We recognize revenues based on monthly meter readings, which are based on the quantity of natural gas or electricity used and the approved rates. We accrue unbilled revenues for natural gas and electricity that have been delivered, but not yet billed, at the end of an accounting period, to the extent that billing and delivery do not coincide.

Revenues for Eastern Shore are based on rates approved by the FERC. The FERC has also authorized Eastern Shore to negotiate rates above or below the FERC-approved maximum rates, which customers can elect as an alternative to the FERC-approved maximum rates. Eastern Shore's services can be firm or interruptible. Firm services are offered on a guaranteed basis and are available at all times unless prevented by force majeure or other permitted curtailments. Interruptible customers receive service only when there is available capacity or supply. Our performance obligation is satisfied over time as we deliver natural gas to the customers' locations. We recognize revenues based on capacity used or reserved and the fixed monthly charge.

Peninsula Pipeline is engaged in natural gas intrastate transmission to third-party customers and certain affiliates in the State of Florida. Our performance obligation is satisfied over time as the natural gas is transported to customers. We recognize revenue based on rates approved by the Florida PSC and the capacity used or reserved. We accrue unbilled revenues for transportation services provided and not yet billed at the end of an accounting period.

Aspire Energy Express is engaged in natural gas intrastate transmission in the State of Ohio. We currently serve the Guernsey power plant and our performance obligation is satisfied over time as the natural gas is transported to the plant. We recognize revenue based on rates approved by the Ohio PSC and the capacity used or reserved. We accrue unbilled revenues for transportation services provided and not yet billed at the end of an accounting period.

Revenues generated from the Unregulated Energy segment are not subject to any federal, state, or local pricing regulations. Aspire Energy primarily sources gas from hundreds of conventional producers and performs gathering and processing functions to maintain the quality and reliability of its gas for its wholesale customers. Aspire Energy's performance obligation is satisfied over time as natural gas is delivered to its customers. Aspire Energy recognizes revenue based on the deliveries of natural gas at contractually agreed upon rates (which are based upon an established monthly index price and a monthly operating fee, as applicable). For natural gas customers, we accrue unbilled revenues for natural gas that has been delivered, but not yet billed, at the end of an accounting period, to the extent that billing and delivery do not coincide with the end of the accounting period.

Eight Flags' CHP plant, which is located on land leased from a customer, produces three sources of energy: electricity, steam and heated water. This customer purchases the steam (unfired and fired) and heated water, which are used in the customer’s production facility. Our electric distribution operation purchases the electricity generated by the CHP plant for distribution to its customers. Eight Flags' performance obligation is satisfied over time as deliveries of heated water, steam and electricity occur. Eight Flags recognizes revenues over time based on the amount of heated water, steam and electricity generated and delivered to its customers.

For our propane distribution operations, we recognize revenue based upon customer type and service offered. Generally, for propane bulk delivery customers (customers without meters) and wholesale sales, our performance obligation is satisfied when we deliver propane to the customers' locations (point-in-time basis). We recognize revenue from these customers based on the number of gallons delivered and the price per gallon at the point-in-time of delivery. For our propane distribution customers with meters, we satisfy our performance obligation over time. We recognize revenue over time based on the amount of propane consumed and the applicable price per unit. For propane distribution metered customers, we accrue unbilled revenues for propane that is estimated to have been consumed, but not yet billed, at the end of an accounting period, to the extent that billing and delivery do not coincide with the end of the accounting period.

Marlin Gas Services provides mobile CNG and pipeline solutions primarily to utilities and pipelines. Marlin Gas Services provides temporary hold services, pipeline integrity services, emergency services for damaged pipelines and specialized gas services for customers who have unique requirements. Marlin Gas Services' performance obligations are comprised of the compression of natural gas, mobilization of CNG equipment, utilization of equipment and on-site CNG support. Our performance obligations for the compression of natural gas, utilization of mobile CNG equipment and for the on-site CNG staff support are satisfied over time when the natural gas is compressed, equipment is utilized or as our staff provide support services to our customers. Our performance obligation for the mobilization of CNG equipment is satisfied at a point-in-time when the equipment is delivered to the customer project location. We recognize revenue for CNG services at the end of each calendar month for services provided during the month based on agreed upon rates for equipment utilized, costs incurred for natural gas compression, miles driven, mobilization and demobilization fees.

The timing of revenue recognition, customer billings and cash collections results in trade receivables, unbilled receivables (contract assets), and customer advances (contract liabilities) in our consolidated balance sheets. The balances of our trade receivables, contract assets, and contract liabilities as of December 31, 2023 and 2022 were as follows:



	Trade Receivables		Contract Assets (Current)		Contract Assets (Noncurrent)		Contract Liabilities (Current)
(in thousands)
Balance at 12/31/2022	$	61,687	$	18	$	4,321	$	983
Balance at 12/31/2023	67,741		18		3,524		1,022
Increase (decrease)	$	6,054	$	—	$	(797)	$	39

Our trade receivables are included in trade and other receivables in the consolidated balance sheets. Our non-current contract assets are included in receivables and other deferred charges in the consolidated balance sheet and relate to operations and maintenance costs incurred by Eight Flags that have not yet been recovered through rates for the sale of electricity to our electric distribution operation pursuant to a long-term service agreement.

At times, we receive advances or deposits from our customers before we satisfy our performance obligation, resulting in contract liabilities. Contract liabilities are included in other accrued liabilities in the consolidated balance sheets and relate to non-refundable prepaid fixed fees for our propane distribution operation's retail offerings. Our performance obligation is satisfied over the term of the respective retail offering plan on a ratable basis. For the years ended December 31, 2023 and 2022, the amounts recognized in revenue were not material.

Our businesses have long-term fixed fee contracts with customers in which revenues are recognized when performance obligations are satisfied over the contract term. Revenue for these businesses for the remaining performance obligations at December 31, 2023 are expected to be recognized as follows:


(in thousands)	2024		2025		2026		2027		2028		2029 and thereafter
Eastern Shore and Peninsula Pipeline	$	36,657	$	30,330	$	26,547	$	23,433	$	22,559	$	149,124
Natural gas distribution operations	9,680		9,216		8,501		6,472		5,252		28,428
FPU electric distribution	652		275		275		275		275		—
Total revenue contracts with remaining performance obligations	$	46,989	$	39,821	$	35,323	$	30,180	$	28,086	$	177,552