Solar procurement is the sequence of decisions that turns a rough interest in solar power into a signed contract: measuring what the site actually needs, choosing how to pay for the system, locking in who owns the tax benefits and renewable energy credits, and putting all of it into a request for proposal that competing installers can bid on the same way. Those decisions bind you for 20 to 25 years, and the order in which you make them matters. Financing structure alone can shift total cost by tens of thousands of dollars, and a single missed clause about credits or end-of-term buyouts can wipe out the savings that justified the project.
Start With Usage Data and Site Suitability
Pull 12 to 24 months of utility bills before anything else. That history tells you how many kilowatt-hours the property consumes across seasons, and it is the single most important input for sizing the array. Oversizing is not just wasted spending. Many utilities cap how much excess generation earns credits, so a system that produces more than you use can generate power you can neither consume nor sell back at a useful rate.
A physical site evaluation comes next. Inspectors check roofing material, age, and structural capacity to confirm the surface can carry panels for the life of the system, and a structural engineer may calculate dead load and wind load tolerances. Ground-mounted arrays require review of soil stability, drainage, and local setback rules that dictate how far panels must sit from property lines.
Shading is where marginal sites drop out. Specialized tools calculate the Total Solar Resource Fraction, a measure of what percentage of available sunlight actually reaches the proposed panel locations across the year. Heavy afternoon shading from trees or neighboring buildings can rule out a site regardless of how favorable the financing looks.
Pick a Financing Structure
The financing model decides who owns the equipment, who claims the tax benefits, who handles maintenance, and what happens if you sell the property. Three structures dominate.
Direct Purchase
Buying outright gives you full ownership and every financial benefit attached. A typical residential installation runs roughly $2.74 to $3.30 per watt before incentives, which puts a standard home system in the $20,000 to $30,000 range; commercial installations scale into the hundreds of thousands or millions depending on capacity.1Department of Energy. Solar Photovoltaic System Cost Benchmarks Direct owners claim the federal tax credit, any available depreciation, and every renewable energy credit the system produces. You also absorb the entire upfront cost and take on maintenance and repairs.
Power Purchase Agreement
In a power purchase agreement, a third-party developer installs, owns, and maintains the system on your property, and you buy the electricity it produces at a contracted rate. The EPA notes that PPA rates are usually at or slightly below the host customer’s standard retail electricity rate, and most agreements include an annual price escalator of 1% to 5%.2US EPA. Solar Power Purchase Agreements Terms run 6 to 25 years. The developer keeps the tax credits and depreciation, which is what funds the below-retail price. You put up no capital, but you do not own the hardware or the renewable attributes unless the contract explicitly gives them to you.
Solar Lease
A lease looks similar to a PPA but pays differently. You pay a fixed monthly amount regardless of how much electricity the system produces. That predictability suits organizations that want stable budgets, but you owe the same amount during cloudy months when production drops. The leasing company keeps ownership, maintenance responsibility, and the tax benefits. Leases are common among nonprofits and municipalities that have limited federal tax liability and cannot use the credits directly.
Federal Tax Incentives Attach to Ownership
Tax incentives often separate a mediocre return from a compelling one, and the credits attach to whoever owns the system. That is why the financing choice and the tax analysis have to happen together.
The Clean Electricity Investment Credit (Section 48E)
For solar projects beginning construction in 2025 or later, the relevant federal incentive is the clean electricity investment credit under Section 48E of the Internal Revenue Code, which replaced the older Section 48 energy credit for new projects.3Office of the Law Revision Counsel. 26 USC 48E – Clean Electricity Investment Credit The base credit is 6% of the qualified investment. It rises to 30% if the project meets either of the following:
- The system has a maximum net output under 1 megawatt of alternating current, or
- The project pays construction workers no less than applicable prevailing wages and employs apprentices from registered programs for a required number of hours.4Internal Revenue Service. Prevailing Wage and Apprenticeship Requirements
Most residential systems fall well under the 1 MW threshold and automatically qualify for the 30% rate. Commercial and industrial projects above 1 MW have to build prevailing wage and apprenticeship compliance into their procurement contracts from the start. The difference between 6% and 30% on a $2 million installation is $480,000.5Internal Revenue Service. Clean Electricity Investment Credit
Depreciation Under MACRS
Business owners who purchase solar equipment can recover its cost through the Modified Accelerated Cost Recovery System over a five-year schedule, even though the panels will produce power for 25 years or more.6Office of the Law Revision Counsel. 26 USC 168 – Accelerated Cost Recovery System Federal bonus depreciation lets a percentage of the system’s adjusted basis be deducted in the first year, with the remainder spread across the five-year period. Bonus depreciation percentages have changed several times under the Tax Cuts and Jobs Act phase-down and later legislation, so confirm the current first-year percentage with a tax professional before finalizing procurement. Depreciation belongs to the system owner, which is why PPA and lease structures funnel it to the developer rather than the property host.
The Residential Clean Energy Credit (Section 25D)
Homeowners who buy systems outright can claim a personal tax credit under Section 25D. The credit covered 30% of installation costs for systems placed in service from 2022 through 2032.7Office of the Law Revision Counsel. 26 USC 25D – Residential Clean Energy Credit There is no prevailing wage requirement and no income limit. The credit reduces your federal tax bill dollar-for-dollar and can be carried forward to future tax years if it exceeds what you owe. Homeowners who finance through a PPA or lease cannot claim it, because they do not own the equipment.
Renewable Energy Credits Are a Separate Asset
Every megawatt-hour of solar electricity generates a renewable energy certificate, or REC, that represents the environmental attributes of that power. The REC is legally separate from the electricity itself. Whoever holds it has the exclusive right to claim they are using renewable energy. Sell the RECs and you forfeit that claim, even though the panels are on your roof.8US EPA. Guidance in Making Claims
Under direct ownership, you hold both the power and the RECs by default. You can retire them for sustainability goals or sell them as a revenue stream, with prices that vary widely by region.9US EPA. Renewable Energy Certificate Monetization Some owners use REC arbitrage: selling higher-value solar RECs and buying cheaper RECs from other renewable sources to maintain their environmental claims at a lower net cost.
Under a PPA, the developer usually keeps the RECs unless the contract says otherwise. This is where procurement negotiations matter most for organizations with sustainability reporting or green building certification obligations. If your company needs to claim renewable energy use, the PPA has to explicitly transfer REC ownership to you. Skipping that clause is one of the most common and costly procurement mistakes.
Building the Request for Proposal
The RFP translates the site data and financing choice into a solicitation that installers can bid on. The Department of Energy’s Better Buildings program publishes a standardized template covering scheduling, scope, and evaluation criteria that organizations can customize.10Better Buildings & Better Plants Initiative. Solar PV RFP and Procurement Guidance Template
A workable RFP includes the structural findings from the site assessment, 12 to 24 months of usage data, and the preferred financing structure. Naming whether you want a direct purchase, PPA, or lease lets vendors tailor financial projections rather than guess. Include the meter location, current panel capacity, and any known utility interconnection requirements so bidders can estimate labor accurately.
Hardware Specifications
Define minimum equipment standards in the document itself. Many procurement professionals require panels from manufacturers classified as “Tier 1” by Bloomberg New Energy Finance, a designation based on financial stability, production capacity, and product quality rather than any official certification. Specify panel technology (monocrystalline versus polycrystalline), minimum efficiency, and required certifications to narrow the field to comparable bids. For inverters, require compliance with UL 1741, the safety standard for grid-interactive equipment, which mandates protections against overcurrent, overvoltage, and safe response to grid failures.
Warranty Requirements
The industry standard for panels is a 10-year product warranty covering manufacturing defects and a 25-year performance warranty guaranteeing minimum power output. Inverter warranties vary by type: string inverters typically carry 10 to 15 years, microinverters often 25 years. Setting minimum warranty durations in the RFP prevents vendors from bidding cheaper equipment with shorter coverage. Ask bidders to identify the warranty provider too, since some manufacturers use third-party administrators that may not exist in 15 years.
Bidding and Vendor Selection
Send the RFP to at least three to five installers and allow four to six weeks for responses. Vendors usually need a site visit to verify dimensions and electrical configurations before submitting final numbers. Keep a single communication channel for questions so all bidders get the same clarifications; giving one bidder details others lack undermines the competition.
Score bids with a standardized matrix that weights price per watt, equipment quality, warranty terms, and installer track record. A common split assigns roughly 40% of the score to financial value and distributes the rest across technical competence, timeline, and references. Flag any bid that relies on unrealistic production estimates. An inflated kilowatt-hour projection makes every downstream financial model look better than it will actually perform.
Before signing, verify insurance coverage. Industry recommendations call for general liability of at least $1 million per occurrence and $2 million aggregate, workers’ compensation of $1 million per accident, and automobile liability of $1 million per occurrence. Contractors doing design work should carry professional liability, and those handling customer data should carry cyber liability. Require certificates of insurance as part of the bid response so you can confirm coverage before selection.
Interconnection and Permission to Operate
Once you pick a contractor, the next bottleneck is the utility. The installer submits an interconnection application, and the utility reviews whether the transformer and distribution lines can absorb the power the system will export. Application fees vary by jurisdiction and system size. Review usually takes several weeks; complex commercial projects can take longer. Construction generally begins after the utility grants preliminary design approval.
After the panels and inverters go in, a local electrical inspector verifies the wiring meets applicable building codes. The utility then performs its own final review and issues a Permission to Operate, the formal authorization to energize the system. No electricity should flow before that letter arrives. Energizing without utility approval can create safety hazards for line workers and may violate your interconnection agreement.
Net Metering and Excess Generation
Net metering rules decide how you get paid for electricity your system sends back to the grid. Roughly 38 states and Washington, D.C. have some form of mandatory net metering, though the credit structures vary. Some programs credit exported power at the full retail rate, so each kilowatt-hour exported offsets one at the same price you would have paid. Others use a reduced feed-in tariff that credits exports below retail.
The rule feeds directly back into sizing. In jurisdictions with full retail crediting, a slightly oversized system can zero out an electric bill. In areas with reduced-rate crediting, oversizing wastes money because the surplus earns less than it cost to generate. Ask bidders to model production against the specific net metering rules that will apply.
What Happens If You Sell the Property
If you sell a property with a leased or PPA-financed system, the agreement either transfers to the buyer or gets bought out before closing. Most solar contracts are filed with the county recorder, so they show up in the buyer’s title search regardless. The buyer usually needs approval from the solar company and must agree to assume the remaining terms. If the buyer refuses, the seller may need to buy out the remaining contract or offer a credit to offset the future payments.
A UCC-1 financing statement on title from the solar company is not a lien against the home; it simply notifies buyers that the equipment belongs to the financing company. Releasing or subordinating that filing typically carries a document processing fee.
For directly owned systems, the transfer is simpler. The panels are your property and convey with the sale like any other fixture. Over half of states offer some form of property tax exemption for solar energy systems, which can keep the added value of the panels from raising the buyer’s tax bill. Confirm whether your state offers this exemption before listing, since it changes how buyers price the system.
End-of-Term and Decommissioning
Panels last 25 to 30 years, and today’s procurement decisions determine what happens at the end. PPA and lease contracts should spell out end-of-term options, which typically include renewing at a renegotiated rate, having the developer remove the equipment, or buying the system at fair market value. Fair market value buyouts are usually set by an independent appraiser who looks at remaining useful life, current performance, and the net present value of expected future output.
For directly owned systems, decommissioning is on you. Recycling a panel costs roughly $15 to $45, well above the $1 to $5 cost of landfill disposal. No federal law currently mandates solar panel recycling, though Washington state requires manufacturers to operate take-back programs, and other states are considering similar rules. A typical residential system has 20 to 30 panels, so end-of-life costs stay modest. Commercial arrays with thousands of panels face a more meaningful expense that belongs in the original financial model.
If you have a PPA or lease and the contract runs to term without a buyout, confirm in writing who is responsible for removal and site restoration. Some contracts leave this ambiguous. You do not want to discover at year 25 that the developer has gone out of business and left you with equipment you do not own but cannot legally remove.