Annual report pursuant to Section 13 and 15(d)

Summary of Significant Accounting Policies (Policies)

Summary of Significant Accounting Policies (Policies)
12 Months Ended
Dec. 31, 2021
Accounting Policies [Abstract]  
Principles of Consolidation
Principles of Consolidation
The accompanying consolidated financial statements include the accounts of Ameresco, our subsidiaries, certain contracts in which we have a controlling financial interest and four investment funds formed to fund the purchase and operation of solar energy systems, which are consolidated with Ameresco as VIEs. We use a qualitative approach in assessing the consolidation requirement for VIEs. This approach focuses on determining whether we have the power to direct the activities of the VIE that most significantly affect the VIE’s economic performance and whether we have the obligation to absorb losses or the right to receive benefits that could potentially be significant to the VIE. For all periods presented, we have determined that we are the primary beneficiary in all of our operational VIEs. We evaluate our relationships with the VIEs on an ongoing basis to ensure that we continue to be the primary beneficiary. All significant intercompany accounts and transactions have been eliminated. Gains and losses from the translation of all foreign currency financial statements are recorded in accumulated other comprehensive loss, net, within stockholders’ equity. We prepare our consolidated financial statements in conformity with the accounting principles generally accepted in the United States of America (“GAAP”). Certain prior period amounts were reclassified or rounded to conform to the presentation in the current period.
Certain prior period amounts were reclassified to conform to the presentation in the current period.
Use of Estimates
Use of Estimates
GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the consolidated financial statements and the reported amounts of revenue and expenses during the reporting period. Changes in circumstances could cause actual results to differ materially from those estimates. The most significant estimates and assumptions used in these consolidated financial statements relate to management’s estimates of final construction contract profit in accordance with accounting for long-term contracts, allowance for credit losses, inventory reserves, realization of project development costs, leases, fair value of derivative financial instruments, accounting for business acquisitions, stock-based awards, impairment of goodwill and long-lived assets, asset retirement obligations (“AROs”), income taxes, self-insurance reserves, potential liability in conjunction with certain commitments and contingencies, and recognition of the investors’ share of net assets of certain subsidiaries as redeemable non-controlling interests.
Self-insured Health Insurance
Self-insured Health Insurance
We are self-insured for employee health insurance and the maximum exposure in fiscal year 2021 under the plan was $150 per covered participant, after which reinsurance takes effect. The liability for unpaid claims and associated expenses, including incurred but not reported claims, is determined by management and reflected in our consolidated balance sheets in accrued expenses and other current liabilities. The liability is calculated based on historical data, which considers both the frequency and
settlement amount of claims. Our estimated accrual for this liability could be different than our ultimate obligation if variables such as the frequency or amount of future claims differ significantly from management’s assumptions.
Cash and Cash Equivalents Cash and Cash EquivalentsCash and cash equivalents include cash on deposit, overnight repurchase agreements and amounts invested in highly liquid money market funds. Cash equivalents consist of short-term investments with original maturities of three months or less. We maintain our accounts with financial institutions and the balances in such accounts, at times, exceed federally insured limits. This credit risk is divided among a number of financial institutions that management believes to be of high quality.
Restricted Cash
Restricted Cash 
Restricted cash consists of cash and cash equivalents held in escrow accounts in association with operations and maintenance (“O&M”) reserve accounts, cash collateralized letters of credit, as well as cash required under term loans to be maintained in reserve accounts until all obligations have been indefeasibly paid in full for energy assets. The carrying amount of the cash and cash equivalents in these accounts approximates its fair value measured using level 1 inputs per the fair value hierarchy as defined in Note 18. Restricted cash also includes funds held for clients, which represent assets that, based upon our intent, are restricted for use solely for the purposes of satisfying the obligations to remit funds to third parties, primarily utility service providers, relating to our enterprise energy management services.
Accounts Receivable
Accounts Receivable 
Accounts receivable are stated at the amount management expects to collect from outstanding balances. Our methodology to estimate the allowance for credit losses includes quarterly assessments of historical bad debt write-off experience, current economic and market conditions, management’s evaluation of outstanding accounts receivable, anticipated recoveries and our forecasts. Due to the short-term nature of our receivables, the estimate of credit losses is primarily based on aged accounts receivable balances and the financial condition of our customers. In addition, specific allowance amounts are established to record the appropriate provision for customers that have a higher probability of default. Bad debts are written off against the allowance when identified. As part of our assessment, we also considered the current and expected future economic and market conditions due to the COVID-19 pandemic and determined that the estimate of credit losses was not significantly impacted as of December 31, 2021 and 2020.
Accounts Receivable Retainage Accounts Receivable Retainage Accounts receivable retainage represents amounts due from customers, but where payments are withheld contractually until certain construction milestones are met. Amounts retained typically range from 5% to 10% of the total invoice. We classify retainages that are expected to be billed in the next twelve months as current assets.
Inventories, which consist primarily of PV solar panels, batteries and related accessories, are stated at the lower of cost (“first-in, first-out” method) or net realizable value (determined as the estimated selling prices in the ordinary course of business, less reasonably predictable costs of completion, disposal, and transportation). Provisions have been made to reduce the carrying value of inventory to the net realizable value.
Federal ESPC Receivable
Federal ESPC Receivable
Federal ESPC receivable represents the amount to be paid by various federal government agencies for work performed and earned by Ameresco under specific ESPCs. We assign certain of our rights to receive those payments to third-parties that provide construction and permanent financing for such contracts. Upon completion and acceptance of the project by the government, typically within 24 to 36 months of construction commencement, the assigned ESPC receivable from the government and corresponding ESPC liability are eliminated from our consolidated financial statements.
Project Development Costs Project Development CostsWe capitalize only those costs incurred in connection with the development of energy projects, primarily direct labor, interest costs, outside contractor services, consulting fees, legal fees, and travel, if incurred after a point in time where the realization of related revenue becomes probable. Project development costs incurred prior to the probable realization of revenue are expensed as incurred. We classify project development efforts that are expected to proceed to construction activity in the next twelve months as a current asset. We periodically review these balances and write off any amounts where the realization of the related revenue is no longer probable.
Property and Equipment
Property and Equipment
Property and equipment consist primarily of office and computer equipment, and is recorded at cost. Major additions and improvements are capitalized as additions to the property and equipment accounts, while replacements, maintenance, and repairs that do not improve or extend the life of the respective assets, are expensed as incurred. Depreciation and amortization of property and equipment are computed on a straight-line basis over the following estimated useful lives:
Asset Classification   Estimated Useful Life
Furniture and office equipment   Five years
Computer equipment and software costs  
Three to five years
Leasehold improvements  
Lesser of term of lease or five years
Five years
Land Unlimited
Gains or losses on disposal of property and equipment are reflected in selling, general, and administrative expenses in the consolidated statements of income.
Energy Assets
Energy Assets 
Energy assets consist of costs of materials, direct labor, interest costs, outside contract services, deposits, and project development costs incurred in connection with the construction of small-scale renewable energy plants that we own. These amounts are capitalized and amortized to cost of revenues in our consolidated statements of income on a straight-line basis over the lives of the related assets or the terms of the related contracts.
Routine maintenance costs are expensed as incurred in our consolidated statements of income to the extent that they do not extend the life of the asset. Major maintenance, upgrades, and overhauls are required for certain components of our energy assets. In these instances, the costs associated with these upgrades are capitalized and are depreciated over the shorter of the remaining life of the asset or the period up to the next required major maintenance or overhaul.
Financing lease assets and accumulated depreciation of financing lease assets are included in energy assets. For additional information see the Sale-Leaseback section below and Notes 7 and 8.
Capitalized Interest
We capitalize interest costs relating to construction financing during the period of construction on energy assets we own. Capitalized interest is included in energy assets, net, in our consolidated balance sheets. Capitalized interest is amortized to cost of revenues in our consolidated statements of income on a straight-line basis over the useful life of the associated energy asset.
Long-lived Asset Impairment
We evaluate our long-lived assets, including operating lease right-of-use assets, for impairment as events or changes in circumstances indicate the carrying value of these assets may not be fully recoverable. Examples of such triggering events applicable to our assets include a significant decrease in the market price of a long-lived asset or asset group or a current-period operating or cash flow loss combined with a history of operating or cash flow losses or a projection or forecast that demonstrates continuing losses associated with the use of a long-lived asset or asset group.
We evaluate recoverability of long-lived assets to be held and used by estimating the undiscounted future cash flows before interest associated with the expected uses and eventual disposition of those assets. When these comparisons indicate that the carrying value of those assets is greater than the undiscounted cash flows, we recognize an impairment loss for the amount that the carrying value exceeds the fair value of the asset group. Impairment losses are reflected in selling, general, and administrative expenses in the consolidated statements of income.
Government Grants
From time to time, we have applied for and received cash grant awards from the U.S. Treasury Department (the “Treasury”) under Section 1603 of the American Recovery and Reinvestment Act of 2009 (the “Act”). The Act authorized the Treasury to make payments to eligible persons who place in service qualifying renewable energy projects. The grants are paid in lieu of investment tax credits. All of the cash proceeds from the grants were used and recorded as a reduction in the cost basis of the applicable energy assets. If we dispose of the property, or the property ceases to qualify as specified energy property, within five years from the date the property is placed in service, then a prorated portion of the Section 1603 payment must be repaid. For tax purposes, the Section 1603 payments are not included in federal and certain state taxable income and the basis of the property is reduced by 50% of the payment received.
We last received a Section 1603 grant during the year ended December 31, 2014. No further Section 1603 grant payments are expected to be received as the program has expired and no repayments will be required.
For acquisitions that meet the definition of a business combination, we apply the acquisition method of accounting in accordance with Accounting Standards Codification (“ASC”) 805, Business Combinations, where assets acquired and liabilities assumed are recorded at fair value at the date of each acquisition. Any excess of the consideration we transferred over the amounts recognized for assets acquired and liabilities assumed is recorded as goodwill. Intangible assets, if identified, are also recorded.
Determining the fair value of certain assets and liabilities assumed is judgmental in nature, often involves the use of significant estimates and assumptions, and is calculated using level 3 inputs per the fair value hierarchy as defined in Note 18. We continue to evaluate acquisitions for a period not to exceed one year after the acquisition date of each transaction to determine whether any additional adjustments are needed to the allocation of the purchase price. The results of the acquired companies are included in our consolidated statements of income, comprehensive income, and cash flows from the date of the respective acquisition.
The consideration for our acquisitions often includes future payments that are contingent upon the occurrence of a particular event. We record a contingent consideration obligation for such contingent consideration payments at fair value on the acquisition date. We estimate the fair value of contingent consideration obligations through valuation models that incorporate probability adjusted assumptions related to the achievement of the milestones and the likelihood of making related payments. Each reporting period we revalue the contingent consideration obligations associated with our acquisitions to fair value and record changes in the fair value within the selling, general, and administrative expenses in our consolidated statements of income. Increases or decreases in the fair value of the contingent consideration obligations can result from changes in assumed discount periods and rates, changes in the assumed timing and amount of revenue and expense estimates and changes in assumed probability with respect to the attainment of certain financial and operational metrics, among others. Significant judgment is employed in determining these assumptions as of the acquisition date and for each subsequent period. Accordingly, future business and economic conditions, as well as changes in any of the assumptions described above, can materially impact the fair value of contingent consideration recorded at each reporting period. Deferred consideration related to certain holdbacks and completion payments are considered short-term in nature. These amounts are recorded at full value and are only revalued if one of those underlying assumptions changes. See Note 4 for additional information about our acquisitions.
In accordance with ASC 805, Business Combinations, our solar project acquisitions do not constitute a business as the assets acquired in each case could be considered a single asset or group of similar assets that made up substantially all of the fair market value of the acquisitions.
Goodwill and Intangible Assets
As noted in the Acquisitions section above, our goodwill is derived when we acquire another business. Goodwill is not amortized, but the potential impairment of goodwill is assessed at least annually (December 31st) and on an interim basis whenever events or changes in circumstances indicate that the carrying value may not be fully recoverable.
We estimate the fair value of our reporting units and compare it with the carrying value of the reporting unit, including goodwill. If the fair value is greater than the carrying value of the reporting unit, no impairment is recorded. Fair value is determined using both an income approach and a market approach. If the fair value is less than the carrying value, an impairment loss is recognized for the amount that the carrying amount of a reporting unit, including goodwill, exceeds its fair value, limited to the total amount of goodwill allocated to that reporting unit. The impairment charge would be recorded to earnings in the consolidated statements of income. Judgment is required in determining whether an event has occurred that may impair the value of goodwill or identifiable intangible assets.
Intangible Assets
Acquired intangible assets, other than goodwill, that are subject to amortization include customer contracts, customer relationships, technology, trade names and non-compete agreements. The intangible assets are amortized over periods ranging from one to fifteen years from their respective acquisition dates. We evaluate our intangible assets for impairment consistent with, and part of, our long-lived asset evaluation, as discussed in Energy Assets above.
Leases / Sale-leasebacks
Operating lease right-of-use (“ROU”) assets represent our right to use an underlying asset during the reasonably certain lease term and lease liabilities represent our obligation to make lease payments arising from the lease. ROU assets and lease liabilities for significant lease arrangements are recognized at commencement based on the present value of lease payments over the lease term. We use our incremental borrowing rate, which is updated annually or when a significant event occurs that would indicate a significant change in rates, to calculate the present value of lease payments. The operating lease ROU asset also includes any lease payments related to initial direct cost and prepayments and excludes lease incentives. Lease expense is recognized on a straight-line basis over the lease term which may include options to extend or terminate the lease when it is reasonably certain that we will exercise that option. Our ROU assets are evaluated for impairment using the same method as described above under the Long-lived Asset Impairment section.
We do not record ROU assets and corresponding lease liabilities for leases with an initial term of 12 months or less (“short-term leases”) as we recognize lease expense for these leases as incurred over the lease term.
We elected the package of practical expedients and did not reassess lease classifications of existing contracts or leases at adoption or the initial direct costs associated with existing leases. Accordingly, our sale-leaseback arrangements entered into as of December 31, 2018 remain under the previous guidance. See the Sale-leasebacks section below and Note 8 for additional information on these sale-leasebacks.
We have historical leases under ASC 840, Leases, which may have lease and non-lease components. Upon adoption of Topic 842, we elected to continue to account for these historical leases as a single component, as permitted by Topic 842. As of January 1, 2019, as it relates to all prospective leases, we allocate consideration to lease and non-lease components based on pricing information in the respective lease agreement, or, if this information is not available, we make a good faith estimate based on the available pricing information at the time of the lease agreement.
We entered into sale-leaseback arrangements that provided for the sale of solar PV energy assets to third-party investors and the simultaneous leaseback of the energy assets, which we then operate and maintain, recognizing revenue through the sale of the electricity and solar renewable energy credits generated by these energy assets.
In sale-leaseback arrangements, we first determine whether the solar PV energy asset under the sale-leaseback arrangement is “integral equipment”. A solar PV energy asset is determined to be integral equipment when the cost to remove the energy asset from its existing location, including the shipping and reinstallation costs of the solar PV energy asset at the new site, and any diminution in fair value, exceeds 10% of the fair value of the solar PV energy asset at the time of its original installation. When the leaseback arrangement expires, we have the option to purchase the solar PV energy asset for the then fair market value or, in certain circumstances, renew the lease for an extended term. We have determined that none of the solar PV energy assets sold to date under the sale-leaseback program have been considered integral equipment as the cost to remove the energy asset from its existing location would not exceed 10% of its original fair value.
For solar PV energy assets that are not considered integral equipment, we determine if the leaseback should be classified as a financing lease or an operating lease. We determined that most of the solar PV energy assets sold to date under the sale-leaseback program have been financing leases and we initially recorded a financing lease asset and financing lease obligation in our consolidated balance sheets equal to the lower of the present value of our future minimum leaseback payments or the fair value of the solar PV energy asset. We deferred any gain or loss, which represents the excess or shortfall of cash received from the investor compared to the net book value of the asset, at the time of the sale. We record the long-term portion of any deferred gain in other liabilities or deferred loss in other assets and the current portion in accrued expenses and other current liabilities or prepaid expenses and other current assets in our consolidated balance sheets. The deferred amounts are amortized over the lease term and are included in cost of revenues in our consolidated statements of income.
In accordance with our adoption of Topic 842, sale-leaseback transactions are accounted for as financing liabilities on a prospective basis as we retain control of the underlying assets. As these transactions meet the criteria of a failed sale, the proceeds received in prospective transactions, as of January 1, 2019, are accounted for as long-term financing liabilities with interest rates based upon the underlying details of each specific transaction.
Other Assets
Other Assets
Other assets consist primarily of notes and contracts receivable due to Ameresco from various customers and also includes the fair value of derivatives determined to be assets, the non-current portions of project development costs, accounts receivable retainages, sale-leaseback deferred loss and deferred contract costs.
Asset Retirement Obligations Asset Retirement ObligationsWe recognize a liability for the fair value of required AROs on a discounted basis when these obligations are incurred and can be reasonably estimated, which is typically at the time the assets are in development, installed or operating. Over time, the liabilities increase due to the change in present value, and initial capitalized costs are depreciated over the useful life of the related assets. Upon satisfaction of the ARO conditions, any difference between the recorded ARO liability and the actual retirement cost incurred is recognized as an operating gain or loss in the consolidated statements of income.
Federal ESPC Liabilities
Federal ESPC Liabilities
Federal ESPC liabilities, for both projects and energy assets, represent the advances received from third-parties under agreements to finance certain ESPC projects with various federal government agencies. For projects related to the construction or installation of certain energy savings equipment or facilities developed for the government customer, the ESPC receivable from the government and corresponding ESPC liability is eliminated from our consolidated balance sheets upon completion and acceptance of the project by the government, typically within 24 to 36 months of construction commencement. We remain the primary obligor for financing received until recourse to us ceases for the ESPC receivables transferred to the investor upon final acceptance of the work by the government customer.
For small-scale energy assets developed for a government customer that we own and operate, we remain the primary obligor for financing received until the liability is eliminated from our consolidated balance sheets as contract payments assigned by the customer are transferred to the investor upon final acceptance of the work by the government customer.
Debt Issuance Costs
Debt Issuance Costs
Debt issuance costs include external costs incurred to obtain financing. Debt issuance costs are amortized over the respective term of the financing using the effective interest method, with the exception of our revolving credit facility and construction loans, as discussed in Note 9, which are amortized on a straight-line basis over the term of the agreement. Debt issuance costs are presented on the consolidated balance sheets along with unamortized debt discounts as a reduction to long-term debt and financing lease liabilities.
Other Liabilities Other LiabilitiesOther liabilities consist primarily of the long-term portion of deferred revenue related to multi-year operation and maintenance contracts which expire at various dates through 2047. Other liabilities also include the fair value of derivatives and the long-term portions of sale-leaseback deferred gains.
Revenue Recognition/Cost of Revenues
Revenue Recognition
We are a provider of comprehensive energy services, including energy efficiency, infrastructure upgrades, energy security and resilience, asset sustainability, and renewable energy solutions for businesses and organizations. Our sustainability services include capital and operational upgrades to a facility's energy infrastructure and the development, construction, ownership, and operation of renewable energy plants. Our revenue is generated from the primary lines of business described below and is recognized in accordance with Revenue from Contracts with Customers (Topic 606).
Our Projects service relates to energy efficiency projects, which include the design, engineering, and installation of an array of innovative technologies and techniques to improve energy efficiency and control the operation of a building’s energy- and water-consuming systems. Renewable energy products and services include, but are not limited to, the design and construction of a
central plant or cogeneration system providing power, heat and/or cooling to a building, or a small-scale plant that produces electricity, gas, heat or cooling from renewable sources of energy.
We recognize revenue from the installation or construction of projects over time using the cost-based input method. We use the total costs incurred on the project relative to the total expected costs to account for the satisfaction of the performance obligation. When the estimate on a contract indicates a loss, or reduces the likelihood of recoverability of such costs, we record the entire estimated loss in the period the loss becomes known. In addition, some contracts contain an element of variable consideration, including liquidated damages and/or penalties, which requires payment to the customer in the event that construction timelines or milestones are not met. We estimate the total consideration payable by the customer when the contracts contain variable consideration provisions, based on the most likely amount anticipated to be recognized for transferring the promised goods or services. As a result, we may constrain revenue to the extent that a significant reversal in the amount of cumulative revenue recognized will not occur when the uncertainty associated with the variable consideration is subsequently resolved.
Contracts are often modified for a change in scope or other requirements. Contract modifications exist when the modification either creates new or changes the existing enforceable rights and obligations. Most of our contract modifications are for goods or services that are not distinct from the existing performance obligations. The effect of a contract modification on the transaction price, and the measure of progress for the performance obligation to which it relates, is recognized as an adjustment to revenue (either as an increase or decrease) on a cumulative catch-up basis.
After an energy efficiency or renewable energy project is completed, we often provide ongoing O&M services under a multi-year contract. These services include operating, maintaining and repairing facility energy systems such as boilers, chillers, and building controls, as well as central power and other small-scale plants. For larger projects, we frequently maintain staff on-site to perform these services.
Maintenance revenue is recognized using the input method to recognize revenue. In most cases, O&M fees are fixed annual fees and we record the revenue on a straight-line basis because the on-site O&M services are typically a distinct series of promises and those services have the same pattern of transfer to the customer (i.e., evenly over time). Some O&M service contract fees are based on time expended and in those cases, revenue is recorded based on the time expended in that month.
Energy Assets
Our service offerings include the sale of electricity, heat, cooling, processed biogas, and renewable biomethane fuel from the portfolio of assets that we own and operate. We have constructed and are currently designing and constructing a wide range of renewable energy plants using biogas, solar, biomass, other bio-derived fuels, wind, and hydro sources of energy. Most of our renewable energy projects to date have involved the generation of electricity from solar PV and the sale of electricity, thermal, renewable fuel, or biomethane using biogas as a feedstock. We purchase the biogas that otherwise would be combusted or vented, process it, and either sell it or use it in our energy plants. We have also designed and built, own, operate and maintain plants that take biogas generated in the anaerobic digesters of wastewater treatment plants and turn it into renewable natural gas that is either used to generate energy on-site or that can be sold through the nation’s natural gas pipeline grid. We typically enter into a long-term power purchase agreement (“PPA”) for the sale of the energy where we own and operate energy producing assets. Many of our energy assets also produce environmental attributes, including renewable energy credits and RINs. In most cases, we sell these attributes under separate agreements with parties other than the PPA customer.
In accordance with specific PPA contract terms, we recognize revenues from the sale and delivery of the energy output from renewable energy plants over time as produced and delivered to the customer. Environmental attributes revenue is recognized at a point in time when the environmental attributes are transferred to the customer in accordance with the transfer protocols of the environmental attributes market that we operate in. In the cases where environmental attributes are sold to the same customer as the energy output, we record revenue monthly for both the energy output and the environmental attribute output, as generated and delivered to the customer. We have determined that certain PPAs contained a lease component in accordance with ASC 840, Leases, prior to the adoption of Topic 842. We recognized $11,726, $9,143 and $8,189 of operating lease revenue under these agreements during the years ended December 31, 2021, 2020, and 2019, respectively.
Our service and product offerings also include integrated-PV, engineering, consulting, and enterprise energy management services, which we recognize over time as the services are provided. We recognize revenue from the sale of solar materials at a point in time when we have transferred physical control of the asset to the customer upon shipment or delivery.
Performance Obligations
A performance obligation is a promise in a contract to transfer a distinct good or service to the customer and is the unit of account. Performance obligations are satisfied as of a point in time or over time and are supported by contracts with customers. For most of our contracts, there are multiple promises of goods or services. Typically, we provide a significant service of integrating a complex set of tasks and components such as design, engineering, construction management, and equipment procurement for a project contract. The bundle of goods and services are provided to deliver one output for which the customer has contracted. In these cases, we consider the bundle of goods and services to be a single performance obligation. We may also promise to provide distinct goods or services within a contract, such as a project contract for installation of energy conservation measures and post-installation O&M services. In these cases we separate the contract into more than one performance obligation and allocate the total transaction price to each performance obligation in an amount based on the estimated relative standalone selling prices of the promised goods or services underlying each performance obligation.
Contract Acquisition Costs
We are required to account for certain acquisition costs over the life of the contract, consisting primarily of commissions. Commission costs are incurred commencing at contract signing. Commission costs are allocated across all performance obligations and deferred and amortized consistent with the pattern of revenue recognition.
Contract Assets and Contract Liabilities
Contract assets represent our rights to consideration in exchange for services transferred to a customer that have not been billed as of the reporting date. Our rights to consideration are generally unconditional at the time our performance obligations are satisfied. Unbilled revenue, presented as costs and estimated earnings in excess of billings, represent amounts earned and billable that were not invoiced at the end of the fiscal period.
When we receive consideration, or such consideration is unconditionally due, from a customer prior to transferring goods or services to the customer under the terms of a sales contract, we record deferred revenue, which represents a contract liability. Deferred revenue, presented as billings in excess of cost and estimated earnings, typically results from billings in excess of costs incurred and advance payments received on project contracts.
At the inception of a contract, we expect the period between when we satisfy our performance obligations, and when the customer pays for the services, will be one year or less. As such, we elected to apply the practical expedient which allows us not to adjust the promised amount of consideration for the effects of a significant financing component, when a financing component is present.
Cost of Revenues
Cost of revenues includes the cost of labor, materials, equipment, subcontracting and outside engineering that are required for the development and installation of projects, as well as preconstruction costs, sales incentives, associated travel, inventory obsolescence charges, amortization of intangible assets related to customer contracts, and, if applicable, costs of procuring financing. A majority of our contracts have fixed price terms, however, in some cases we negotiate protections, such as a cost-plus structure, to mitigate the risk of rising prices for materials, services, and equipment.
Cost of revenues also includes the costs of maintaining and operating the small-scale renewable energy plants that we own, including the cost of fuel (if any) and depreciation charges.
Income Taxes
Income Taxes
We account for income taxes based on the liability method that requires the recognition of deferred income taxes based on expected future tax consequences of differences between the financial statement basis and the tax basis of assets and liabilities. We calculate deferred income taxes using the enacted tax rates in effect for the year in which the differences are expected to be reflected in the tax return.
We account for uncertain tax positions using a “more-likely-than-not” threshold for recognizing and resolving uncertain tax positions. The evaluation of uncertain tax positions is based on factors that include changes in tax law, the measurement of tax positions taken or expected to be taken in tax returns, the effective settlement of matters subject to audit, new audit activity and changes in facts or circumstances related to a tax position. We evaluate uncertain tax positions on a quarterly basis and adjust the level of the liability to reflect any subsequent changes in the relevant facts surrounding the uncertain positions.
Our liabilities for uncertain tax positions can be relieved only if the contingency becomes legally extinguished through either payment to the taxing authority or the expiration of the statute of limitations, the recognition of the benefits associated with the position meet the “more-likely-than-not” threshold or the liability becomes effectively settled through the examination process.
We consider matters to be effectively settled once the taxing authority has completed all of its required or expected examination procedures, including all appeals and administrative reviews; we have no plans to appeal or litigate any aspect of the tax position; and we believe that it is highly unlikely that the taxing authority would examine or re-examine the related tax position. We also accrue for potential interest and penalties related to unrecognized tax benefits as a component of income tax expense.
Under the guidance, we have recorded long term deferred tax assets and deferred tax liabilities based on the underlying jurisdiction in the consolidated balance sheets as of December 31, 2021 and 2020, respectively.
Foreign Currency Foreign Currency The local currency of our foreign operations is considered the functional currency of such operations. All assets and liabilities of these foreign operations are translated into U.S. dollars at year-end exchange rates. Income and expense items are translated at average exchange rates prevailing during the year. Translation adjustments are accumulated as a separate component of stockholders’ equity. Foreign currency translation gains and losses are reported in the consolidated statements of comprehensive income. Foreign currency transaction gains and losses are reported within other expenses, net in the consolidated statements of income.
Fair Value Measurements
Fair Value Measurements
We follow the guidance related to fair value measurements for all of our non-financial assets and non-financial liabilities, except for those recognized at fair value in the financial statements at least annually. These assets include goodwill and long-lived assets measured at fair value for impairment assessments, and non-financial assets and liabilities initially measured at fair value in a business combination.
We recognize our financial assets and liabilities at fair value on a recurring basis (at least annually). Fair value is defined as the price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market
for the asset or liability in an orderly transaction between market participants on the measurement date. Three levels of inputs that may be used to measure fair value are as follows:
Level 1: Inputs are based on unadjusted quoted prices for identical instruments traded in active markets. 
Level 2: Inputs are based on quoted prices for similar instruments in active markets, quoted prices for identical or similar instruments in markets that are not active, and model-based valuation techniques for which all significant assumptions are observable in the market or can be corroborated by observable market data for substantially the full term of the assets or liabilities. 
Level 3: Inputs are generally unobservable and typically reflect management’s estimates of assumptions that market participants would use in pricing the asset or liability. The fair values are therefore determined using model-based techniques that include option pricing models, discounted cash flow models, and similar techniques.
Financial Instruments
Financial instruments consist of cash and cash equivalents, restricted cash, accounts and notes receivable, long-term contract receivables, accounts payable, accrued expenses and other current liabilities, financing lease assets and liabilities, contingent consideration, short- and long-term borrowings, make-whole provisions, interest rate swaps, and commodity swaps. Because of their short maturity, the carrying amounts of cash and cash equivalents, restricted cash, accounts and notes receivable, accounts payable, accrued expenses and other current liabilities, contingent consideration, and short-term borrowings approximate fair value.
The carrying value of long-term variable-rate debt approximates fair value. As of December 31, 2021, the carrying value of our long-term debt is less than its fair value of $442,429 by approximately $5,537. Fair value of our debt is based on quoted market prices or on rates available to us for debt with similar terms and maturities, which are level two inputs of the fair value hierarchy, as defined in Note 18.
Stock-based Compensation Expense
Stock-based Compensation Expense
We measure and record stock-based compensation expense for all stock-based payment awards based on estimated fair value. We may provide stock-based awards of shares of restricted common stock and grants of stock options to employees, directors, outside consultants, and others through various equity plans including our Employee Stock Purchase Plan (the “ESPP”) for employees.
Stock-based compensation expense, net of actual forfeitures, is recognized based on the grant-date fair value on a straight-line basis over the requisite service period of the awards. Certain option grants have performance conditions that must be achieved prior to vesting and are expensed based on the expected achievement at each reporting period. We estimate the fair value of the stock-based awards, including stock options, using the Black-Scholes option-pricing model. Determining the fair value of stock-based awards requires the use of highly subjective assumptions, including the fair value of the common stock underlying the award, the expected term of the award and expected stock price volatility.
The assumptions used in determining the fair value of stock-based awards represent management’s estimates, which involve inherent uncertainties and the application of management judgment. The risk-free interest rates are based on the U.S. Treasury yield curve in effect at the time of grant, with maturities approximating the expected life of the stock options.
We have no history of paying dividends. Additionally, as of each of the grant dates, there was no expectation that we would pay dividends over the expected life of the options. The expected life of the awards is estimated based upon the period stock option holders will retain their vested options before exercising them. We use historical volatility as the expected volatility assumption required in the Black-Scholes model.
We recognize compensation expense for only the portion of options that are expected to vest. If there are any modifications or cancellations of the underlying invested securities or the terms of the stock option, it may be necessary to accelerate, increase or cancel any remaining unamortized stock-based compensation expense.
Derivative Financial Instruments
Derivative Financial Instruments
In the normal course of business, we utilize derivatives contracts as part of our risk management strategy to manage exposure to market fluctuations in interest and commodity rates. These instruments are subject to various credit and market risks. Controls and monitoring procedures for these instruments have been established and are routinely reevaluated. Credit risk represents the potential loss that may occur because a party to a transaction fails to perform according to the terms of the contract. The measure of credit exposure is the replacement cost of contracts with a positive fair value. We seek to manage credit risk by entering into financial instrument transactions only through counterparties that we believe are creditworthy.
Market risk represents the potential loss due to the decrease in the value of a financial instrument caused primarily by changes in interest rates and commodity prices. We seek to manage market risk by establishing and monitoring limits on the types and degree of risk that may be undertaken. As a matter of policy, we do not use derivatives for speculative purposes and consider the use of derivatives with all financing transactions to mitigate risk.
We account for our interest rate and commodity swaps as derivative financial instruments in accordance with ASC Topic 815, Derivatives and Hedging. Under this guidance, derivatives are carried on our consolidated balance sheets at fair value which is determined based on observable market data in combination with expected cash flows for each instrument. We account for our make-whole provisions as embedded derivatives in accordance with related guidance. Under this guidance, the derivative is bifurcated from its host contract and recorded on our consolidated balance sheets at fair value by either comparing it against the rates of similar debt instruments under similar terms without a make-whole provision obtained from various highly rated third-party pricing sources or evaluating the present value of the prepayment fee.
We recognize cash flows from derivative instruments not designated as hedges as operating activities in the consolidated statements of cash flows. We recognize all changes in fair value on interest rate swaps designated as effective cash flow hedges in our consolidated statements of comprehensive income. Changes in fair value on derivatives not designated as hedges are recognized in our consolidated statements of income.
Earnings Per Share Earnings Per ShareBasic earnings per share is calculated using our weighted-average outstanding common shares, including vested restricted shares. When the effects are not anti-dilutive, diluted earnings per share is calculated using the weighted-average outstanding common shares; the dilutive effect of convertible preferred stock, under the “if converted” method; and the treasury stock method with regard to warrants and stock options; all as determined under the treasury stock method.
Variable Interest Entities
Variable Interest Entities
Certain contracts are executed jointly through partnership and joint venture arrangements with unrelated third parties. The arrangements are often formed for the single business purpose of executing a specific project and allow us to share risks and/or secure specialty skills required for project execution.
We evaluate each partnership and joint venture at inception to determine if it qualifies as a VIE under ASC 810, Consolidation. A variable interest entity is an entity used for business purposes that either (i) does not have equity investors with voting rights or (ii) has equity investors who are not required to provide sufficient financial resources for the entity to support its activities without additional subordinated financial support. Upon the occurrence of certain events outlined in ASC 810, we reassess our initial determination of whether the partnership or joint venture is a VIE.
We also evaluate whether we are the primary beneficiary of each VIE and consolidate the VIE if we have both (i) the power to direct the economically significant activities of the entity and (ii) the obligation to absorb losses of, or the right to receive benefits from, the entity that could potentially be significant to the VIE. We consider the contractual agreements that define the ownership structure, distribution of profits and losses, risks, responsibilities, indebtedness, voting rights and board representation of the respective parties in determining whether we qualify as the primary beneficiary. We also consider all parties that have direct or implicit variable interests when determining whether we are the primary beneficiary. As required by ASC 810, management's assessment of whether we are the primary beneficiary of a VIE is continuously performed.
We generally aggregate the disclosures of our VIEs based on certain qualitative and quantitative factors including the purpose and design of the underlying VIEs, the nature of the assets in the VIE, and the type of involvement we have with the VIE including our role and type of interest held in the VIE. As of December 31, 2021, all the VIEs that make up our investment funds are similar in purpose, design, and our involvement and, as such, are aggregated in one disclosure.
Equity Method Investments Equity Method InvestmentsWe have entered into a number of joint ventures and using the methodology described above for VIEs, we determined that we are not the primary beneficiary. We do not consolidate the operations of these joint ventures and treat the joint ventures as equity method investments.
Redeemable Non-Controlling Interests
Redeemable Non-Controlling Interests
In September 2015, June 2017, June 2018, October 2018 and December 2019, we formed investment funds with different third-party investors which granted the applicable investor ownership interests in the net assets of certain of our renewable energy project subsidiaries. As of December 31, 2021, we have four such investment funds each with a different third-party investor.
We entered into these agreements in order to finance the costs of constructing energy assets which are under long-term customer contracts. We have determined that these entities qualify as VIEs and that we are the primary beneficiary in the operational partnerships for accounting purposes. Accordingly, we consolidate the assets and liabilities and operating results of the entities in our consolidated financial statements. We recognize the investors’ share of the net assets of the subsidiaries as redeemable non-controlling interests in our consolidated balance sheets.
We have determined that the provisions in the contractual arrangements represent substantive profit-sharing arrangements and that the appropriate methodology for attributing income and loss to the redeemable non-controlling interests each period is a balance sheet approach referred to as the hypothetical liquidation at book value (“HLBV”) method. Under the HLBV method, the amounts of income and loss attributed to the redeemable non-controlling interests in the consolidated statements of income reflect changes in the amounts the investors would hypothetically receive at each balance sheet date under the liquidation provisions of the contractual agreements, assuming the net assets of this funding structure were liquidated at recorded amounts. The investors’ non-controlling interest in the results of operations of this funding structure is determined as the difference in the non-controlling
interest’s claim under the HLBV method at the start and end of each reporting period, after taking into account any capital transactions, such as contributions or distributions, between our subsidiaries and the investors.We classified the non-controlling interests with redemption features that are not solely within our control outside of permanent equity on our consolidated balance sheets. The redeemable non-controlling interests will be reported using the greater of their carrying value at each reporting date as determined by the HLBV method or the estimated redemption values in each reporting period.
Recent Accounting Pronouncements
Recent Accounting Pronouncements
Income Taxes
In December 2019, the Financial Accounting Standards Board (the “FASB”) issued Accounting Standards Update (“ASU”) 2019-12, Simplifying the Accounting for Income Taxes, which simplifies the accounting for income taxes, eliminates certain exceptions within ASC 740, Income Taxes, and clarifies certain aspects of the current guidance to promote consistency among reporting entities. ASU 2019-12 is effective for our fiscal year beginning after December 15, 2020. We adopted this guidance as of January 1, 2021 and the adoption did not have an impact on our consolidated financial statements.
Reference Rate Reform
In March 2020, the FASB issued ASU 2020-04, Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting. ASU 2020-04, which provides optional guidance for a limited period of time to ease the potential burden in accounting for (or recognizing the effects of) reference rate reform on financial reporting. Companies can apply the ASU immediately, however, the guidance will only be available until December 31, 2022. We are currently evaluating the impact that adopting this new accounting standard would have on our consolidated financial statements and related disclosures.
In January 2021, the FASB issued ASU 2021-01, Reference Rate Reform (Topic 848): Scope. The amendments in ASU 2021-01 provide optional expedients to the current guidance on contract modification and hedge accounting from the expected market transition from LIBOR and other interbank offered rates to alternative reference rates. The guidance generally can be applied to applicable contract modifications through December 31, 2022. We are currently evaluating the impact that adopting this new accounting standard would have on our consolidated financial statements and related disclosures.
Codification Improvements
In October 2020, the FASB issued ASU 2020-10, Codification Improvements. The amendments in this ASU represent changes to clarify the ASC, correct unintended application of guidance, or make minor improvements to the ASC that are not expected to have a significant effect on current accounting practice or create a significant administrative cost to most entities. ASU 2020-10 is effective for annual periods beginning after December 15, 2020 and interim periods within those annual periods, with early adoption permitted. The amendments in this ASU should be applied retrospectively. We adopted this guidance as of January 1, 2021 and the adoption did not have an impact on our consolidated financial statements.
Business Combinations
In October 2021, the FASB issued ASU 2021-08, Business Combinations (Topic 805): Accounting for Contract Assets and Contract Liabilities from Contracts with Customers, which requires entities to apply Topic 606 to recognize and measure contract assets and contract liabilities in a business combination. ASU 2021-08 is effective for our fiscal year beginning after December 15, 2022, however, early adoption is permitted. We early adopted this new accounting standard as of January 1, 2021 and applied it to our December 2021 acquisition discussed in Note 4. We elected the practical expedient related to contract modifications made before the acquisition date and the adoption did not have a material impact on our consolidated financial statements.
Government Assistance
In November 2021, the FASB issued ASU 2021-10, Government Assistance (Topic 832): Disclosures by Business Entities about Government Assistance, Accounting for Contract Assets and Contract Liabilities from Contracts with Customers, which requires annual disclosures about certain types of government assistance received. ASU 2021-10 is effective for our fiscal year beginning after December 15, 2021. We are currently evaluating the impact that adopting this new accounting standard would have on our consolidated financial statements.