Solar ITC for Commercial Real Estate: Section 48E Credits, Bonus Adders, and MACRS Interaction

Key Takeaways

What Is the Solar ITC

The solar investment tax credit is a federal incentive that reduces the income tax liability of a taxpayer who installs qualified solar energy property on a commercial building. Unlike a deduction (which reduces taxable income), the ITC is a credit (which reduces tax owed dollar for dollar). A $300,000 ITC on a $1,000,000 solar installation can offset up to $300,000 of federal income tax for the year the system is placed in service, subject to the general business credit limitation (IRC 38(c)) and, for individual and pass-through investors, the passive activity rules (IRC 469). Unused credits carry back 1 year and forward 20 years (IRC 39).

For commercial real estate, the solar ITC applies to photovoltaic (PV) systems installed on rooftops, parking structures, ground-mounted arrays on owned parcels, and building-integrated photovoltaics (BIPV). The credit is claimed by the owner of the solar property, which is typically the building owner or a special-purpose entity structured for tax credit monetization. The IRS provides an overview of the clean electricity investment credit that now governs commercial solar installations.

The 30% solar ITC dates from the Energy Policy Act of 2005 (the Section 48 energy credit itself is older), but the Inflation Reduction Act of 2022 (IRA) restructured it significantly. The IRA replaced the flat 30% credit with a tiered structure that rewards compliance with labor standards (prevailing wage and apprenticeship requirements) and offers bonus adders for projects that meet additional policy objectives. The subsequent One Big Beautiful Bill Act (OBBBA, signed July 2025) added a December 31, 2027 placed-in-service cutoff for solar facilities that begin construction after July 4, 2026. That date divides projects into two tracks: facilities that began construction on or before July 4, 2026, which are exempt from the cutoff, and facilities that began later, which earn the credit only if placed in service by the end of 2027.

From a real estate underwriting perspective, the solar ITC is a capital stack tool. It reduces the effective cost of a solar installation by 30% to 70% (depending on bonus adder eligibility), which changes the return profile of a property acquisition, development, or capital improvement. The credit, combined with accelerated depreciation under MACRS, can make solar installations accretive to property-level returns even in markets where electricity savings alone would not justify the capital expenditure.

Section 48 vs Section 48E

The IRA created two parallel investment tax credit provisions. Understanding which applies to a given project is the first step in any solar ITC analysis.

Section 48: The Legacy Credit

IRC Section 48 is the original investment tax credit for energy property, in effect for decades. Under the IRA, Section 48 continues to apply to solar property for which construction begins before January 1, 2025. The credit rate under Section 48 is 30% (or 6% without PWA compliance) for solar energy property, with the same bonus adder structure as Section 48E.

Solar projects beginning construction in 2025 or later fall under Section 48E rather than Section 48. However, projects that commenced construction before January 1, 2025 (and can document that fact through the IRS safe harbors) remain eligible for the Section 48 credit even if they are not placed in service until later.

Section 48E: The Clean Electricity Investment Credit

IRC Section 48E, added by the IRA, is the technology-neutral clean electricity investment credit. It applies to any qualified facility that generates electricity with an anticipated greenhouse gas emissions rate not greater than zero. Solar PV qualifies. Section 48E applies to qualified facilities placed in service after December 31, 2024. Section 48 applies to solar property only if construction began before January 1, 2025. Facilities that began construction before 2025 but are placed in service after 2024 can potentially qualify under either section, but not both.

The mechanics are nearly identical to Section 48 for solar projects: same base credit rates (6% or 30%), same bonus adders, same PWA requirements. The key difference is that Section 48E is technology-neutral (it covers wind, geothermal, nuclear, and other zero-emission technologies alongside solar) and was designed to be the successor to the technology-specific Section 48 credit.

For CRE developers evaluating rooftop solar in 2026, Section 48E is the operative statute. The OBBBA modified Section 48E by terminating the credit for solar facilities placed in service after December 31, 2027, but only for facilities whose construction begins after July 4, 2026. It also added prohibited foreign entity restrictions. These changes are discussed in detail in the OBBBA Timeline Changes section below.

Base Credit and PWA Requirements

The IRA established a two-tier credit structure. The base credit is 6% of the cost of qualified solar energy property. If the project satisfies prevailing wage and apprenticeship (PWA) requirements, the credit increases fivefold to 30%. This is not a bonus; it is the mechanism Congress chose to link the full credit to labor standards.

The 6% Base Credit

Projects that do not meet PWA requirements receive a 6% investment tax credit. For a $1,000,000 solar installation, the credit would be $60,000. At this level, the ITC alone rarely justifies a commercial solar installation; the 6% rate was intentionally designed to be insufficient, pushing developers toward PWA compliance.

There is one exception: facilities with a maximum net output of less than 1 MW AC are exempt from PWA requirements and still receive the full 30% credit. This is significant for CRE developers because many rooftop installations on individual buildings fall below the 1 MW AC threshold. As an illustrative assumption, a 50,000 square foot commercial roof might support roughly 200 to 400 kW of rooftop solar, well within the exemption.

The 30% Enhanced Credit with PWA Compliance

To qualify for the full 30% credit on facilities of 1 MW AC or greater, the developer must pay prevailing wages during construction and for alteration or repair work during the 5 years after placement in service, and must meet apprenticeship requirements during construction.

Prevailing Wage Requirement

All laborers and mechanics employed in the construction, alteration, or repair of the solar facility must be paid wages at rates not less than the prevailing rates determined by the Secretary of Labor under the Davis-Bacon Act. The prevailing wage rates are published by the Department of Labor's Wage and Hour Division and vary by county, trade, and type of construction.

The prevailing wage requirement applies during construction and for 5 years after the facility is placed in service (covering maintenance and repair work). This means that if you hire electricians to perform maintenance on the solar array in year 3 of operation, those electricians must be paid prevailing wages. The requirement runs with the project, not just the construction phase.

Compliance steps for prevailing wage:

• Determine the correct wage determination for the project's county and type of construction (building, heavy, highway, or residential) using the SAM.gov wage determination database.
• Include the applicable wage determination in all construction contracts and subcontracts.
• As a best practice, obtain certified payroll records from all contractors and subcontractors.
• Retain payroll and apprenticeship records sufficient to substantiate compliance for as long as the credit can be examined.
• Ensure prevailing wages apply to maintenance and repair contractors for 5 years post-placement.

Apprenticeship Requirement

A minimum percentage of total labor hours must be performed by qualified apprentices participating in registered apprenticeship programs. The required percentage depends on when construction began:

• Construction beginning before 2023: 10% of total labor hours
• Construction beginning in 2023: 12.5% of total labor hours
• Construction beginning in 2024 or later: 15% of total labor hours

The 15% labor-hour requirement is measured across the total construction labor hours of the facility, including all contractors and subcontractors, and is subject to apprentice-to-journeyworker ratio rules. Separately, each taxpayer, contractor, or subcontractor that employs four or more individuals on the construction must employ at least one qualified apprentice.

There is a good-faith exception: if the taxpayer requests qualified apprentices from a registered apprenticeship program and the request is denied or not responded to within 5 business days, the taxpayer is deemed to have satisfied the apprenticeship requirement. This exception has been critical for solar installations in areas with limited apprenticeship program availability.

Cure Provision for PWA Violations

The IRA includes a cure provision for PWA non-compliance. If a prevailing wage violation is discovered, the taxpayer can retain the full 30% credit by paying each affected worker the shortfall plus interest (at the federal underpayment rate computed with 6 percentage points in place of 3) and paying the IRS a penalty of $5,000 per affected worker. For intentional disregard, the back pay is three times that sum and the penalty is $10,000 per worker. After a final IRS determination, these payments must be made within 180 days. Apprenticeship failures can be cured by a penalty of $50 per labor hour not satisfied ($500 for intentional disregard). This cure mechanism reduces the binary risk of losing the entire 24-percentage-point enhancement due to a single payroll error.

Bonus Adders: Stacking to 70%

Beyond the base 30% credit (with PWA compliance), Section 48E provides three bonus adders that can increase the effective credit rate: domestic content, energy community, and low-income (the last allocated across four categories). Each adder is independent; a project that qualifies for multiple adders receives all of them.

The domestic content and energy community adders are 10 percentage points only for facilities that satisfy PWA or are exempt (under 1 MW AC). For a non-exempt facility that fails PWA, each is 2 points (6% + 2% + 2% = 10% maximum before low-income adders).

Domestic Content Bonus (+10%)

The domestic content bonus adder increases the ITC by 10 percentage points (from 30% to 40%) for projects where the steel, iron, and manufactured components meet domestic sourcing thresholds. IRS Notice 2023-38, as modified by Notices 2024-41 and 2025-08, sets out the requirements (see theIRS domestic content bonus credit page):

• Steel and iron: All structural steel and iron components must be produced in the United States. "Produced" means all manufacturing processes, from initial melting through application of coatings, occur domestically.
• Manufactured components: A minimum percentage of the total cost of manufactured components must be attributable to components mined, produced, or manufactured in the United States. For Section 48E, the threshold depends on when construction begins: 40% before June 16, 2025; 45% from June 16 through December 31, 2025; 50% in 2026; and 55% after 2026 (IRC 48E(a)(3)(B)).

For solar PV, the manufactured components include modules, inverters, racking systems, wiring, and trackers (for ground-mount systems). The domestic content requirement has been challenging for solar because most PV modules are manufactured outside the United States, although domestic module manufacturing capacity has expanded significantly since the IRA's passage. Developers pursuing this adder should confirm supply chain sourcing with their EPC contractor before committing to a domestic content certification in their tax credit documentation.

Energy Community Bonus (+10%)

The energy community bonus adder provides an additional 10 percentage points for solar facilities located in designated energy communities. The IRS has defined three categories of qualifying locations:

• Brownfield sites: Properties previously used for industrial or commercial purposes where redevelopment is complicated by real or perceived contamination. Many industrial properties with rooftop solar potential qualify.
• Metropolitan or non-metropolitan statistical areas with significant fossil fuel employment: Areas where 0.17% or more of direct employment (or 25% or more of local tax revenue) is related to fossil fuel extraction, processing, transport, or storage, and the area has an unemployment rate at or above the national average.
• Coal closure communities: Census tracts (or adjacent tracts) containing a coal mine that closed after 1999 or a coal-fired electric generating unit that retired after 2009.

The IRS publishes annual lists of qualifying energy community census tracts and statistical areas. CRE developers should check their property's census tract against the current list before beginning solar installation planning. The energy community bonus is particularly relevant for industrial properties in former manufacturing or energy-producing regions, which often have large, unobstructed rooftops ideal for solar installations.

Low-Income Community Bonus (+10% or +20%)

The low-income community bonus has two tiers and is allocated by Treasury and the IRS through a separate application process. Only facilities with a maximum net output of less than 5 MW AC are eligible:

• Category 1 (+10 points): Facilities located in a low-income community (census tracts with a poverty rate of at least 20%, or median family income at or below 80% of the applicable statewide or metropolitan median, under IRC 45D(e)).
• Category 2 (+10 points): Facilities located on Indian land.
• Category 3 (+20 points): Facilities that are part of a qualified low-income residential building project: installed on a residential rental building in a covered affordable housing program, with the financial benefits of the electricity allocated equitably among the building's occupants.
• Category 4 (+20 points): Facilities that are part of a qualified low-income economic benefit project, where at least 50% of the financial benefits of the electricity produced go to households with income below 200% of the poverty line or below 80% of area median gross income.

The low-income bonus is capacity-limited. Treasury and the IRS allocate 1.8 GW of direct current capacity annually (plus any carryover) across the four categories. This means the bonus is not available on demand; developers must apply during an allocation round and compete for limited capacity. Applications for the 2026 program year closed August 7, 2026; the IRS schedule shows the 2027 window opening February 1, 2027. For CRE developers with affordable multifamily properties, Category 3 is particularly attractive because it pairs naturally with affordable housing portfolios.

How Adders Stack in Practice

Consider a 600 kW rooftop solar installation on a multifamily affordable housing building located in a qualifying energy community census tract, using domestically manufactured modules:

Table 1. Bonus adder stacking example. A qualifying affordable multifamily project in an energy community with domestic content achieves a 70% effective ITC rate, the statutory maximum, if the low-income allocation is awarded. If only Category 1 (low-income community) applies, the rate is 60%.

In practice, achieving 50% or higher requires careful planning. The domestic content requirement restricts module and inverter sourcing. The energy community qualification depends on the property's geographic location, which is fixed. And the low-income bonus requires a competitive allocation from Treasury and the IRS. The 30% rate is the starting point for a PWA-compliant or exempt project; the adders are incremental value that informed developers pursue when the property and project characteristics align.

MACRS Depreciation and Basis Reduction

The ITC is not the only federal tax benefit available for commercial solar installations. Solar energy property is classified as 5-year MACRS property under the Modified Accelerated Cost Recovery System, meaning the cost of the installation can be depreciated over 5 years (using a half-year convention), or deducted in year 1 under bonus depreciation, rather than over the 27.5- or 39-year depreciation schedule that applies to the building itself. This accelerated depreciation creates significant additional tax benefits in the early years of ownership.

The Half-Credit Rule (Basis Reduction)

When a taxpayer claims the ITC on solar property, the depreciable basis of that property must be reduced. However, the reduction is not equal to the full credit amount. Under the "half-credit rule" (IRC Section 50(c)(3)), the depreciable basis is reduced by 50% of the ITC amount, not 100%.

Here is how this works for a $1,000,000 solar installation with a 30% ITC:

• ITC amount: $1,000,000 x 30% = $300,000
• Basis reduction: $300,000 x 50% = $150,000
• Depreciable basis: $1,000,000 - $150,000 = $850,000

The taxpayer claims a $300,000 ITC and depreciates $850,000 (in year 1 under 100% bonus depreciation, or over the 5-year MACRS schedule if the taxpayer elects out of bonus). Without the half-credit rule (if the full ITC amount reduced basis), the depreciable basis would be only $700,000. The half-credit rule preserves an additional $150,000 of depreciable basis, which translates to roughly $55,500 in additional tax savings at a 37% marginal rate.

Bonus Depreciation in 2026

Bonus depreciation allows taxpayers to deduct a percentage of the cost of qualifying assets in the first year. The Tax Cuts and Jobs Act of 2017 scheduled a phase-down of the bonus rate (the "applicable percentage" in IRC 168(k)(6)). The OBBBA repealed that phase-down and permanently restored 100% bonus depreciation for qualified property acquired after January 19, 2025 (IRC 168(k)(1)(A), as amended by Pub. L. 119-21 sec. 70301). Property is not treated as acquired after the date a written binding contract for its acquisition is entered into, so the older phase-down applies only to property acquired, or under binding contract, before January 20, 2025.

For solar property acquired after January 19, 2025 and placed in service in 2026, 100% bonus depreciation applies to the adjusted depreciable basis (after the ITC basis reduction), unless the taxpayer elects out. Using the example above: the $850,000 depreciable basis generates an $850,000 first-year bonus depreciation deduction, leaving no basis for the regular 5-year MACRS schedule.

Combined Tax Benefit: ITC + MACRS

The combined effect of the ITC and MACRS depreciation is substantial. For a $1,000,000 solar installation acquired after January 19, 2025 and placed in service in 2026, assuming a 30% ITC, 100% bonus depreciation, and a 37% marginal tax rate:

Table 2. Combined ITC and MACRS tax benefits for a $1M solar installation placed in service in 2026. Total federal tax savings are $614,500, about 61% of the installation cost, all in the placed-in-service year.

Total federal tax savings: $300,000 (ITC) + $314,500 (depreciation at 37%) = $614,500, or approximately 61% of the installation cost. A taxpayer that elects out of bonus depreciation gets the same $314,500 in nominal savings, spread over six tax years under the 5-year MACRS half-year convention. This calculation does not include state-level tax benefits, which vary by jurisdiction and are not modeled here.

Direct Pay and Transferability

The IRA introduced two mechanisms that expanded access to the ITC beyond taxpayers with sufficient tax liability to use the credit directly. Both are significant for specific segments of the CRE market.

Direct Pay (Elective Pay) for Tax-Exempt Entities

Under IRC Section 6417, certain tax-exempt entities can elect to receive the ITC as a direct payment from the IRS rather than as a credit against tax liability. Eligible entities include:

• Tax-exempt organizations under IRC Section 501(a)
• State and local governments (and political subdivisions)
• Indian tribal governments
• The Tennessee Valley Authority
• Alaska Native Corporations
• Rural electric cooperatives

Direct pay is particularly relevant for two CRE contexts. First, municipal governments that own public buildings (courthouses, libraries, community centers) can install solar and receive a direct cash payment equal to 30% (or more, with adders) of the installation cost. Second, nonprofit affordable housing developers that own multifamily properties can monetize the ITC without needing a taxable investor, simplifying the deal structure considerably.

For facilities of 1 MW AC or larger, an applicable entity's elective payment is reduced unless the domestic content requirement is met or a statutory exception applies: the payment is multiplied by 90% for 2024 construction starts, 85% for 2025 starts, and 0% for starts after 2025 (IRC 48E(d)(5), 45Y(g)(12)). Systems under 1 MW AC are not subject to this reduction. Under Notice 2024-84, the IRS treats an applicable entity's attestation (with the required recordkeeping) as establishing a domestic content exception for property whose construction begins before the later of January 1, 2027 or the issuance of further guidance.

REITs do not qualify for direct pay because they are taxable entities (even though they typically have minimal federal tax liability due to the dividend deduction). REITs must use the transferability mechanism or a partnership structure to monetize the ITC.

ITC Transferability

Under IRC Section 6418, introduced by the IRA, any taxpayer eligible for the ITC can elect to transfer all or a portion of the credit to an unrelated third-party buyer in exchange for cash. This "transferability" mechanism reduced the need for complex tax equity partnership structures (such as inverted leases or partnership flips) that were previously required to monetize clean energy credits.

Key mechanics of ITC transferability:

• The buyer must be unrelated to the seller (not a related party under IRC Section 267 or 707(b)).
• The transfer is for cash only. No property, services, or other consideration can be part of the transaction.
• The cash received is not taxable income to the seller, and the cash paid is not deductible by the buyer.
• The buyer takes the credit as if they had generated it and applies it against their own tax liability.
• Recapture risk transfers with the credit. If a recapture event occurs, the buyer is liable to the IRS for the recaptured credit; sellers commonly indemnify buyers contractually.
• No transfers to specified foreign entities. Under the OBBBA, a Section 48E credit cannot be transferred to a specified foreign entity (IRC 6418(g)(5)).

Cruxreports market-wide average pricing of $0.913 per dollar for 2026 ITCs in the first half of 2026, below the historical $0.920 to $0.925 range, with prohibited foreign entity risk now the dominant pricing factor and deal size and seller credit quality still mattering. A developer with a $300,000 ITC who transfers the credit at $0.913 per dollar receives $273,900 in cash. The $26,100 "discount" is the buyer's return for providing capital and bearing recapture risk.

For CRE developers, transferability has simplified solar ITC monetization dramatically. Before the IRA, a developer without sufficient tax liability would need to structure a partnership flip or sale-leaseback with a tax equity investor, incurring significant legal costs and adding months to the transaction timeline. With transferability, the developer can simply sell the credit on a marketplace platform and receive cash.

OBBBA Timeline Changes

The One Big Beautiful Bill Act (OBBBA), signed July 4, 2025, added a termination rule to the Section 48E clean electricity investment credit for wind and solar facilities. Under IRC 48E(e)(4), the credit does not apply to solar qualified property placed in service after December 31, 2027. That termination applies only to facilities the construction of which begins after July 4, 2026 (Pub. L. 119-21 sec. 70513(g)(5);Notice 2025-42, sec. 1). July 4, 2026 has now passed, so the beginning-of-construction date splits solar projects into two tracks.

Track 1: Construction Began On or Before July 4, 2026

Facilities that began construction on or before July 4, 2026 are not subject to the December 31, 2027 cutoff. They must instead maintain a continuous program of construction. Under the Continuity Safe Harbor, a facility placed in service by the end of the fourth calendar year after the year construction began is deemed to satisfy that requirement (Notice 2025-42, sec. 4.04). A facility that began construction in 2026 can therefore be placed in service through December 31, 2030 under the safe harbor; after that, continuity is tested on the facts and circumstances.

"Beginning of construction" for this deadline is governed by Notice 2025-42 for facilities that had not begun construction before September 2, 2025. Two methods were available:

• Physical Work Test: The taxpayer begins physical work of a significant nature. For rooftop solar, on-site work may include the installation of racks or other structures to affix PV panels; off-site work can include the manufacture of components such as racks, rails, and inverters under a binding written contract, but not inventory items. Preliminary activities (planning, permitting, financing, engineering studies, site clearing) do not qualify. For most solar facilities, Notice 2025-42 made this the sole method.
• Five Percent Safe Harbor (limited): Notice 2025-42 eliminated the Five Percent Safe Harbor except for low-output solar facilities (maximum net output of 1.5 MW AC or less). Those facilities could still establish beginning of construction by paying or incurring at least 5% of total facility cost. Signing a contract or purchase order alone is not enough; the cost must actually be paid or incurred.

Facilities that began construction before September 2, 2025 rely on the earlier guidance in Notice 2022-61, which applies Notice 2013-29 principles and allowed either the Physical Work Test or the Five Percent Safe Harbor.

Track 2: Construction Began After July 4, 2026

A solar facility that began construction after July 4, 2026 qualifies for Section 48E only if it is placed in service by December 31, 2027. "Placed in service" means the solar system is installed, connected to the grid (or to the building's electrical system), and available for its intended use. For rooftop solar, this means the system is mechanically complete, has passed final electrical inspection, and has received permission to operate (PTO) from the local utility.

Prohibited Foreign Entity (FEOC) Rules

For solar facilities that begin construction after December 31, 2025, no Section 48E credit is allowed if construction includes "material assistance" from a prohibited foreign entity (IRC 48E(b)(6)). This is measured by a material assistance cost ratio that must meet a threshold of 40% for 2026 construction starts, rising 5 points per year to 60% for starts after 2029 (IRC 7701(a)(52)(B)). The credit is also denied if the taxpayer is a specified foreign entity or a foreign-influenced entity (IRC 48E(d)(6)). Credits cannot be transferred to a specified foreign entity (IRC 6418(g)(5)). And IRC 50(a)(4) imposes 100% recapture if, within 10 years of placement in service, the taxpayer makes payments to a specified foreign entity under an arrangement giving that entity effective control over the facility. Beginning of construction for these rules is determined under rules similar to Notices 2013-29 and 2018-59 as in effect on January 1, 2025 (IRC 7701(a)(51)(J), 7701(a)(52)(F)), not under Notice 2025-42. For any 2026 construction start, module, inverter, and racking sourcing is a structuring decision.

What Happens After the Deadlines

The OBBBA did not eliminate clean energy tax credits entirely. The wind and solar termination does not apply to energy storage technology placed in service at a solar facility (IRC 48E(e)(4)(C)). Section 48 is not available for solar property whose construction began after December 31, 2024, and the residential clean energy credit under Section 25D, which homeowners claim, ended for expenditures made after December 31, 2025. Whether any successor credit for solar will be enacted is a matter of future legislation.

For underwriting purposes, assume no Section 48E credit for a solar facility that begins construction after July 4, 2026 and is placed in service after December 31, 2027. For a facility that began construction on or before July 4, 2026, underwrite the credit only with documentation of the start date and a placed-in-service date within the Continuity Safe Harbor. These assumptions should be clearly stated in any pro forma that includes solar ITC benefits.

Worked Example: 500 kW Rooftop Solar

To illustrate how the ITC affects real estate underwriting, consider a concrete scenario: a CRE developer acquiring a 120-unit multifamily apartment building with a flat roof suitable for a 500 kW rooftop solar installation. The property is located in a qualifying energy community census tract. The developer uses domestically manufactured modules and racking, began construction in 2026 (before July 5, 2026) under the Five Percent Safe Harbor, which remained available because the system is a low-output solar facility of 1.5 MW AC or less, and places the system in service in 2026. The example assumes the owner can use the credit and deductions at a 37% federal rate, subject to the IRC 38(c) and 469 limits noted above. Because the building is residential rental property, the owner should also have tax counsel confirm the treatment under IRC 50(b)(2), which bars investment credits for property used in connection with furnishing lodging but excepts "energy property."

Solar Installation Assumptions

Table 3. Solar installation assumptions for the worked example. The 500 kW DC system is below the 1 MW AC PWA exemption threshold, so the domestic content and energy community adders are worth 10 points each.

ITC Calculation

Table 4. ITC calculation showing a 50% effective credit rate through stacking the base credit with domestic content and energy community bonus adders.

MACRS Depreciation Calculation

Table 5. MACRS depreciation with the half-credit rule applied. The 50% ITC reduces the depreciable basis by $250,000 (half of the $500,000 credit), preserving $750,000 of depreciable basis, all deducted in year 1 under 100% bonus depreciation.

Impact on Acquisition Underwriting

Now consider how the solar installation changes the acquisition underwriting for the property. The developer is acquiring the 120-unit multifamily building for $15,000,000 and plans to install the 500 kW rooftop solar system as a capital improvement.

Table 6. Acquisition underwriting comparison. Solar adds $68,000 of Year 1 NOI ($78,000 of electricity savings less $10,000 of illustrative O&M and insurance), raising the yield on total capital from 6.00% to 6.05%. The ITC and depreciation are capital stack items, not NOI: realized at the end of year 1 and discounted at 8%, they are worth $719,907 ($777,500 / 1.08).

The solar installation adds $1,000,000 to total capital deployed, and the $500,000 ITC offsets half the cost, leaving a $500,000 net outlay. Against that net outlay, the remaining tax benefit is depreciation on the $750,000 depreciable basis: $277,500 of tax savings at 37%, all in year 1 under 100% bonus depreciation (about $256,944 in present value at 8%), or over six tax years under regular MACRS. The system also produces $68,000 of net Year 1 savings, a 13.6% cash yield on the $500,000 net outlay before the depreciation benefit, compared with 6.00% for the property alone. Do not add the $719,907 present value on top of the net-capital comparison: that figure already includes the $500,000 ITC used to reduce net capital.

Underwriting Considerations for CRE

The solar ITC interacts with several aspects of commercial real estate underwriting that deserve specific attention.

Property Type Suitability

Not every commercial property is suitable for rooftop solar. The key physical considerations:

• Roof condition and remaining life: Solar panels have a 25-year useful life. Installing them on a roof with only 5 to 10 years of remaining life creates a costly problem. The roof should have at least 15 to 20 years of remaining useful life, or the developer should plan to reroof before installation.
• Structural capacity: As an illustrative assumption, solar panels and racking add roughly 3 to 5 pounds per square foot of dead load. Older buildings may require structural reinforcement, which adds to the installation cost and can reduce the net ITC benefit.
• Shading and orientation: Rooftops with significant shading from taller adjacent buildings, mechanical equipment, or trees will produce less electricity, reducing the economic benefit. South-facing exposure (in the Northern Hemisphere) is ideal.
• Electrical infrastructure: The building's electrical panel and service must accommodate the solar interconnection. Panel upgrades or service upgrades can add materially to the project cost (an illustrative range is $20,000 to $75,000).

The property types most commonly suited for commercial solar are industrial warehouses (large, flat, unobstructed roofs), retail strip centers (long, low-rise structures), multifamily apartment buildings (flat or low-slope roofs), and office buildings with minimal rooftop mechanical equipment.

Ownership Structure and Credit Allocation

The ITC is claimed by the owner of the solar property for tax purposes. In a standard building ownership structure, the building owner installs the solar system and claims the ITC on their own tax return. However, several alternative structures exist:

• Direct ownership: The building owner or operating entity installs and owns the solar system. Simplest structure. The ITC offsets the owner's tax liability (or can be transferred under Section 6418).
• Power Purchase Agreement (PPA): A third-party solar developer installs, owns, and maintains the system. The building owner purchases electricity at a contractual rate (typically below retail). The solar developer claims the ITC. The building owner receives no tax benefit but also bears no installation cost or maintenance risk.
• Solar lease: Similar to a PPA, but the building owner pays a fixed monthly lease payment rather than a per-kWh rate. The lessor claims the ITC.
• Partnership flip: The building owner and a tax equity investor form a partnership. The tax equity investor receives the ITC and depreciation benefits. After a specified period (typically the 5-year recapture period), the building owner buys out the investor's interest. This structure is common for larger installations but involves significant legal costs.

For CRE owners with sufficient tax liability, direct ownership with credit transfer (selling the credit under Section 6418) is typically the most efficient structure. For REITs and tax-exempt entities, PPAs or the direct pay election (for qualifying entities) are the primary paths to solar economics.

Impact on Property Valuation

Solar installations can affect property valuation through several channels. The most direct is the increase in NOI from reduced electricity costs. If a solar system reduces electricity expenses by $78,000 per year on a property valued at a 6% cap rate, the capitalized value of the gross electricity savings is $1,300,000, significantly exceeding the $1,000,000 installation cost (before accounting for the ITC and before solar operating costs).

However, appraisers vary in how they treat solar-related income and expenses. Some capitalize the full electricity savings into NOI. Others treat solar as personal property (rather than real property) and exclude it from the real estate valuation. The treatment can affect loan-to-value ratios, debt sizing, and refinancing proceeds. Developers should discuss the intended solar installation with their lender and appraiser before committing to the project to ensure the anticipated value enhancement will be recognized in the financing.

Insurance and Maintenance

Solar installations increase property insurance premiums; as an illustrative assumption, $1,000 to $5,000 per year for a commercial system. The additional coverage protects against equipment damage, fire risk (rare but consequential), and liability. Ongoing maintenance costs are modest; as an illustrative assumption, $10 to $20 per kW per year for monitoring, cleaning, and inverter maintenance. For a 500 kW system, that implies annual maintenance of approximately $5,000 to $10,000. The worked example above uses $10,000 per year for O&M and insurance combined.

These costs should be included in the underwriting as operating expenses. They reduce the net benefit of the solar installation but do not typically eliminate the economic case, especially when the ITC and MACRS benefits are included in the analysis.

Common Mistakes

These are the errors that most frequently appear in solar ITC underwriting for commercial real estate projects:

• Applying the full ITC to reduce depreciable basis. The half-credit rule means the depreciable basis is reduced by 50% of the ITC amount, not 100%. A developer who reduces basis by the full credit amount will understate depreciation deductions and overstate the effective tax rate on the investment.
• Assuming PWA compliance is automatic. For systems of 1 MW AC or greater, PWA compliance is a deliberate process that requires specific contract language, certified payroll documentation, and ongoing monitoring for 5 years after placed-in-service. Failure to comply drops the credit from 30% to 6%, a loss of 80% of the credit value.
• Misreading the OBBBA placed-in-service cutoff. A solar facility that began construction after July 4, 2026 earns a Section 48E credit only if it is placed in service by December 31, 2027; underwriting a 30% ITC for a new start that will finish in 2028 or later overstates the after-tax return. The reverse error is also costly: a facility that began construction on or before July 4, 2026 (under the Physical Work Test, or by paying or incurring at least 5% of total cost for a low-output facility of 1.5 MW AC or less) is not subject to the 2027 cutoff and can be placed in service within the Continuity Safe Harbor (by the end of the fourth calendar year after construction began).
• Conflating the ITC with an operating income item. The ITC is a one-time tax credit, not annual income. It reduces tax liability in the placed-in-service year (or the year of the election, for transferred credits). Do not capitalize the ITC into NOI or include it in a cap rate calculation. It belongs in the capital stack analysis, not the operating pro forma.
• Ignoring recapture risk in disposition analysis. If the property is sold within 5 years of the solar placed-in-service date, a portion of the ITC must be repaid (and payments to a specified foreign entity under an arrangement giving it effective control over the facility can trigger 100% recapture for 10 years). A developer who underwrites a 3-year hold without accounting for ITC recapture will overstate disposition proceeds and understate the tax obligation.
• Overstating bonus adder eligibility. Each bonus adder has specific qualification criteria. The domestic content bonus requires certified supply chain documentation. The energy community bonus requires the property to be in a specific census tract on the IRS published list. The low-income bonus requires an allocation from Treasury and the IRS. Assuming all three adders without confirming qualification overstates the credit by 30 to 40 percentage points.
• Using the wrong depreciation schedule. Solar energy property is 5-year MACRS property, not 39-year property (commercial buildings) or 27.5-year property (residential rental). Using the building depreciation schedule instead of the solar-specific schedule understates the present value of depreciation deductions by roughly 55% to 62.5% against the 39-year schedule (about 43% to 51% against the 27.5-year schedule) at a 6% to 8% discount rate (end-of-year timing, before bonus depreciation), and by more when 100% bonus depreciation applies.
• Failing to separate land and solar basis. The ITC applies to the cost of the solar energy property only, not the land or the building. In a development project, the solar installation cost must be clearly identified and segregated in the sources and uses to ensure the ITC is calculated on the correct basis.

Related Articles

This article is part of the tax credits underwriting series. Each article covers a different federal credit program relevant to commercial real estate:

• Historic Tax Credits and Qualified Rehabilitation Expenditures. The 20% federal HTC for certified historic structures, QRE calculation, and partnership structuring.
• New Markets Tax Credits (NMTC) and the Leveraged Structure. NMTC allocation mechanics, the leveraged lending structure, and QLICI requirements.
• 45L Energy Credits for Multifamily New Construction. The Section 45L tax credit for energy-efficient residential buildings and multifamily developments.
• Layering Multiple Credits: LIHTC, HTC, and NMTC. How to combine federal tax credit programs on a single project without double-dipping.
• LIHTC 101: How the Program Works. The foundational guide to the Low-Income Housing Tax Credit, including the 4% vs 9% credit structure.