Commercial Solar Proposal Checklist for South Carolina

Use this commercial solar proposal checklist to make competing bids describe the same project before you compare totals. Freeze one owner brief, require five evidence files, and classify every material field as verified, bidder assumption, owner assumption, allowance, excluded, open, or not applicable. A low total is not decision-ready when roof work, switchgear, utility studies, tax assumptions, or closeout obligations sit outside it.

The right outcome is not always “select the highest-scoring bid.” It may be to advance a proposal to diligence, request a best-and-final clarification, redesign and rebid, separate an optional package, or pause. This guide helps a South Carolina owner, CFO, facilities team, procurement lead, landlord, or tenant representative reach that gate without turning a sales estimate into a construction, financial, or legal promise.

The one-page commercial solar proposal checklist

Start with a pass/fail gate. Do not weight or score a proposal until the team can answer each question with a document, drawing, model, contract clause, or responsible reviewer.

Decision file	What it must establish	Do not accept as a substitute
Authority	Contracting parties, signatories, site and utility rights, licenses, insurance, security, and adviser approvals	A logo, salesperson biography, or unnamed “installation partner”
Technical	Common load and tariff data, design basis, DC and AC capacities, equipment schedule, production model, site risks, and open items	A rendering and one annual energy number
Commercial	Gross solar-only cash price, alternates, taxes, fees, allowances, exclusions, payment milestones, and change-order rules	A net price after assumed tax benefits or financing
Execution	Responsibility matrix, dependencies, permits, interconnection, procurement, operating constraints, schedule logic, and delay treatment	“Turnkey” with no exclusions or milestone owners
Acceptance	Inspection, commissioning, pass criteria, monitoring, as-builts, training, warranties, lien releases, punch list, and final acceptance	Permission to operate treated as proof that every contract obligation is complete

Give each field one status: verified, bidder assumption, owner assumption, allowance, excluded, open, or not applicable. Add the evidence filename, revision date, and reviewer. This prevents an attractive score from hiding a material open item.

A proposal may advance when all bidders used the frozen owner brief or quantified their deviations; the physical scope and price bridge reconcile; required parties, rights, and licenses are verified; material structural, electrical, and interconnection risks are priced or assigned; and commissioning, acceptance, and post-close duties are testable. No universal point total can replace those conditions.

Freeze one owner brief before comparing bids

Proposal comparison fails when bidders solve different problems. One bidder may model twelve months of bills while another uses annual consumption. One may include a roof allowance while another assumes the roof is ready. One may price a solar-only base scope while another folds storage or service upgrades into the total.

Issue a version-controlled owner brief to every bidder. At minimum, include:

1. The legal property owner, electric-account holder, intended buyer or obligor, site address, authorized contacts, and available site-control documents.
2. The same electricity bills, interval data, current tariff and riders, plus explanations for closures, vacancies, abnormal production periods, or planned loads.
3. Available roof plans, roof-condition and warranty records, surveys, structural documents, one-lines, equipment schedules, service information, and known operating constraints.
4. The business objective: utility-cost value, sustainability reporting, resilience as a separate alternate, a capital limit, a lease or hold horizon, or another defined outcome.
5. The requested ownership and financing cases, while preserving one visible gross cash price for the same technical scope.
6. Required design, model, commercial, contract, insurance, commissioning, training, and closeout deliverables.

Create an input register with the source, date received, period covered, version, owner, and known limitation of every item. A bidder that substitutes a typical load profile, another tariff, a future expansion, or an assumed roof condition should mark the substitution visibly and quantify its effect where possible. Otherwise, mark the bid non-comparable and clarify it before scoring.

Do not infer the electric provider from the city. Service territories can change within a region, and the account’s current bill controls the starting point. Use the bill and the South Carolina utility directory to locate the provider’s current tariff, rider, application, and interconnection documents.

Verify legal parties, authority, site control, and licenses

Write the full legal name and role of every entity. The proposal brand may not be the contracting company, licensed prime contractor, electrical contractor, engineer, roofer, equipment seller, finance provider, system owner, operator, or warranty obligor.

Party or right	Evidence to request	Reviewer question
Property and roof owner	Deed, lease, roof rights, lender or landlord consent path	Does the buyer control the site for construction and the operating term?
Utility customer	Current bill and authorized-signatory evidence	Who may sign applications, rate elections, and agreements?
Buyer or payment obligor	Exact legal entity and signing authority	Is the entity approving the project the entity taking the obligations?
Contractor and trades	Legal names, scopes, license classifications and current status	Does each entity have the authority required for its assigned work?
Designer and engineer	Discipline, entity, deliverable, seal responsibility where required	Who owns design adequacy and revisions?
Warranty and O&M providers	Written obligor names and service boundaries	Who responds if a product maker, contractor, or service provider changes?

South Carolina law makes license review an award-stage issue. Section 40-11-200(B) of the South Carolina Code says an owner or awarding authority may not consider a bid, sign a contract, or allow work to begin unless the bidder or contractor first obtained the licenses required by that chapter. Use the South Carolina LLR license lookup to verify the exact entity, classification, group, status, and any limitation relevant to the proposed work; have counsel determine which requirements apply.

Record property, roof, parking, ground, access, easement, and utility rights separately. A tenant’s operating interest does not by itself prove authority to encumber a roof, grant site access, or sign an interconnection agreement. Ask lenders, landlords, insurers, and governing bodies only for approvals actually required by the project documents and applicable law. Do not let a bidder’s checklist substitute for the owner’s legal review.

Normalize load, tariff, and project success criteria

Every bidder should use the same source dataset and explain how it was cleaned. The comparison file should identify the billing and interval periods, missing intervals, estimated values, coincident peaks, weather or operating anomalies, and planned changes such as electrification, new production lines, vacancies, or schedule changes.

Require the exact tariff, riders, demand definitions, time periods, fixed charges, import treatment, export treatment, and effective dates used in the value model. Then identify which values came from utility documents and which are escalations or analyst assumptions. Do not use a statewide average rate as the facility’s avoided cost.

Define success before reviewing a savings chart. Examples of legitimate criteria include a maximum capital commitment, a minimum roof-clearance zone, a no-unplanned-outage requirement, a design-load constraint, a board-approved financial hurdle, or delivery of specified sustainability data. These are owner criteria, not universal solar benchmarks.

If the project includes carbon, renewable-use, or environmental claims, identify who owns and retires renewable energy certificates and who may make each claim. The Federal Trade Commission’s Green Guides summary warns against broad, unqualified environmental-benefit claims and explains that selling all RECs can make a claim of using the generated renewable energy misleading. Require the proposed claim, boundary, evidence, and attribute ownership in writing.

Compare design maturity, DC/AC size, and equipment

A conceptual sales layout is useful for screening, but it is not the final design. Require each bidder to state the design stage and list what remains subject to survey, structural review, geotechnical work, electrical study, fire access, equipment availability, permit review, and utility review.

The technical comparison should include:

• array capacity in both kilowatts DC and kilowatts AC;
• layout, orientation, tilt, setbacks, access paths, equipment locations, and point of interconnection;
• module, inverter, racking, monitoring, communications, meter, protection, and major balance-of-system schedule;
• DC/AC ratio and expected clipping treatment;
• stringing or electrical topology appropriate to the design stage;
• listed alternates and substitution rules;
• manufacturer, model, quantity, rating, certification or listing evidence where relevant, and written warranty references;
• design criteria, governing documents, calculations, and professional responsibility; and
• a register of assumptions and unresolved items.

Do not score one bidder higher merely because it proposes more DC capacity. A larger array can change export exposure, clipping, roof loading, electrical work, interconnection review, and the value of each added unit of production. Ask the team to explain how size follows the owner objective and site constraints.

The U.S. Department of Energy provides customizable technical specifications for on-site PV for federal procurement. Those templates do not govern a private South Carolina project, but they illustrate why requirements should be written, reviewed, and tailored instead of left inside a sales presentation.

Audit production evidence without treating an estimate as a promise

Require the production model name and version, weather source and period, coordinates, layout inputs, equipment assumptions, and a complete loss stack. Ask for monthly results and hourly or subhourly results when the utility-value model depends on timing. Shade, soiling, wiring, mismatch, availability, clipping, curtailment, degradation, snow if modeled, and other losses should be named rather than hidden in one factor.

NREL’s PVWatts and System Advisor Model are estimation tools. The SAM commercial-model documentation shows that retail-rate analysis can include time-of-use energy charges, demand charges, tiers, fixed charges, and load data. Results depend on the inputs. A proposal should therefore provide enough information to reproduce or independently test its output.

Keep three ideas separate:

1. Modeled production is an estimate for disclosed design, weather, and loss inputs.
2. Measured production is meter or monitoring data after operation begins, with meter boundaries and availability rules defined.
3. A contractual performance commitment, if offered, exists only in the signed language that defines the metric, measurement, exclusions, correction method, notice, remedy, duration, and responsible obligor.

Do not infer a remedy from an estimate labeled “expected,” “forecast,” or “target.” If one proposal offers a written performance commitment and another does not, compare both the promised metric and the practical remedy—not just the headline value. Route contract interpretation to counsel.

For a full financial-model review, use the separate commercial solar ROI guide. This checklist only verifies that the proposal’s technical output and financial workbook use the same design and source data.

Reconcile roof, structural, electrical, civil, and utility scope

“Turnkey” has no useful comparison value until the proposal lists included work and exclusions. Build a scope matrix with one row for every physical interface.

Interface	Questions that must be answered
Roof	Who assesses condition and remaining service life? Who coordinates with the roof manufacturer? Are repairs, replacement, attachments, access, removal, and reinstalls included or excluded?
Structure	What records and field verification are assumed? Who performs analysis and design? How are reinforcement and concealed conditions treated?
Electrical	What service, switchgear, transformer, protection, controls, trenching, shutdown, testing, and utility-facing work is included?
Civil and site	Are surveys, geotechnical work, drainage, foundations, paving repair, landscaping, fencing, traffic control, and restoration defined?
Fire and life safety	Which access, labeling, shutdown, equipment-location, and review requirements are assumed, and who resolves comments?
Communications	Who provides network access, gateways, data plans, cybersecurity review, monitoring setup, credentials, and data retention?
Permits and utility	Who prepares, submits, pays, responds, redesigns, witnesses, and obtains final approvals?

The South Carolina Building Codes Council adoption page identifies the statewide code-adoption framework, while local authorities administer permitting and can publish additional procedures. Require the bidder to name the authority having jurisdiction, applicable code basis, permit set, responsible design professionals, inspections, and closeout path. The final approved documents—not a generic checklist—control.

Utility approval is a separate dependency. Dominion Energy South Carolina’s business solar process tells applicants to establish system specifications, submit required forms, supporting documents, and fees, and obtain approval before setup and interconnection. Its program page also distinguishes multiple nonresidential rate and billing paths. A proposal should attach the exact current documents for the account and assign application, study, redesign, equipment, meter, inspection, fee, and approval responsibilities.

Santee Cooper’s Solar for Business page distinguishes utility meter information from total system monitoring: its bidirectional meter records energy exchanged with the grid, while total production requires separate monitoring access. That is a useful reminder to define the meter boundary, monitoring hardware, account ownership, commissioning test, and data handoff for the actual provider. Do not apply one utility’s process to another account.

Build a gross-cash price bridge

Start with the gross cash price before financing or assumed tax value. Then reconcile the base scope, mandatory work, add alternates, allowances, unit rates, exclusions, taxes, fees, escalation, price-validity conditions, and owner costs. Keep solar, storage, EV charging, roofing, and major electrical upgrades in separate rows unless the owner deliberately approved a combined base scope.

The bridge should answer:

• What drawing, equipment schedule, and scope revision does the price buy?
• Which surveys, studies, permits, utility charges, freight, taxes, bonds, insurance, access, shutdown, restoration, training, and closeout items are included?
• Which allowances can change, how are actual costs documented, and is unused value credited?
• Which quantities have unit rates or not-to-exceed treatment?
• Who can authorize a change, what notice is required, and can work proceed before written approval?
• What owner-supplied work or third-party cost remains outside the contract?
• What milestone evidence supports each payment, and what amount remains until final closeout?

Price per DC watt can be a diagnostic after scopes are normalized; it is not an award method. The commercial solar cost guide explains the installed-cost boundaries in more detail. This article’s job is to make every bidder price the same owner-approved boundary.

Compare schedule logic and responsibility, not a promised date

Ask for a logic-linked milestone schedule. At minimum, identify contract execution, notices to proceed, surveys and investigations, design submissions, owner reviews, permits, utility application and studies, long-lead release, procurement, site mobilization, planned outages, construction, inspection, commissioning, utility authorization, training, punch list, and final acceptance.

For every milestone, state the owner, predecessor, required input, review period assumption, evidence of completion, and treatment if the assumption changes. Separate contractor-controlled work from owner, landlord, lender, engineer, authority, and utility actions.

Do not turn a proposal date into a completion commitment without reading the contract. Counsel should review notice requirements, extensions, force majeure, owner delay, utility or authority delay, suspension, acceleration, schedule updates, and any remedy or limitation. Operations should approve access hours, staging, security, shutdown windows, dust or noise controls, roof access, traffic management, and continuity plans.

A bid can be better even if its schedule is longer on paper when it identifies real dependencies and assigns them. Conversely, a short bar chart can conceal that engineering, interconnection, procurement, or owner work has not been included.

Keep storage and other alternates separate

Optional storage can change power flow, controls, interconnection, site and fire review, electrical scope, operating strategy, warranty conditions, acceptance tests, and the financial model. Do not bury it inside a combined price or describe it only by a product name.

Create separate base and add-alternate rows for PV and each optional package. Require a separate price, scope, one-line impact, control objective, utility treatment, acceptance plan, warranty and O&M boundary, and financial case. The same rule applies to EV charging, generators, roofing, carports, service upgrades, or load controls.

Use the commercial battery storage cost guide to normalize a storage alternate’s kW, usable kWh, controls, switchgear, fire-review, commissioning, warranty, and lifecycle-cost boundary. Keep that package out of the solar-only price and production comparison.

An alternate should move into the base only after the owner approves the operational need and every bidder has priced a comparable solution. Removing an optional package may be a valid decision outcome; it is not a failure of the solar proposal.

Validate financing, tax, and ROI assumptions separately

A proposal should show a gross cash price even when financing is offered. Identify the system owner, property owner, utility customer, borrower or lessee, payment obligor, and intended recipient of energy, tax, and environmental attributes. Attach the actual term sheet rather than embedding selected payment figures in a solar chart.

For ownership, collateral, transfer, default, buyout, and end-of-term review, use the commercial solar financing guide. For annual cash flow, NPV, IRR, payback, tariff, and downside analysis, use the commercial solar ROI guide. Keep those decisions connected to—but distinct from—the proposal scope comparison.

Tax values are not day-one discounts unless a verified transaction and timing support that treatment. As of August 10, 2026, the IRS’s general Section 48E page describes a 6% base investment credit and conditions for increased amounts, bonuses, transfer, or elective-payment pathways. IRS Notice 2025-42 adds solar-specific construction-start and placed-in-service termination rules. Eligibility depends on the taxpayer, facility, timing, labor rules, documentation, and other facts.

South Carolina Department of Revenue Revenue Ruling 24-2 describes a state credit calculated from qualifying taxpayer-owned purchase and installation cost, but annual use is limited to the lesser of $3,500 per facility or 50% of South Carolina income-tax liability; the credit is nonrefundable and unused amounts may carry forward for up to ten years. This means the calculated credit and the amount usable in a given year can differ materially.

Require a tax schedule that names the taxpayer, provision, source date, assumed eligible basis, percentage, placed-in-service and construction-start facts, labor and sourcing assumptions, annual usability, documentation owner, and zero or delayed case. The current IRS clean-energy cost-recovery page says owners of certain qualified property may be eligible for five-year MACRS, while the Form 3468 instructions address basis and possible recapture. A qualified tax professional must approve the actual treatment.

Compare warranties, monitoring, O&M, and service exhibits

Marketing warranty labels are not enough. Build one row for each product warranty, performance warranty, contractor workmanship obligation, roof-penetration obligation, design obligation, monitoring service, O&M agreement, and any contractual performance commitment.

For each row, record the obligor, beneficiary, covered asset or work, start date, term, conditions, exclusions, degradation or measurement definition if relevant, labor, shipping, access, removal and reinstall, claim procedure, response commitment if offered, remedy, transfer or assignment, and contract precedence. Confirm what survives termination, contractor insolvency, manufacturer change, equipment substitution, building sale, or system transfer.

Monitoring is also a scope. Identify hardware, meters, measurement boundary, communications, data-plan cost, portal administrator, usernames, alerts, retention, API or export access, cybersecurity review, fault triage, truck-roll responsibility, and handoff. Define O&M tasks, frequency, reports, exclusions, price adjustment, replacement responsibility, and emergency process without inventing a universal service level.

Sunburst’s warranty overview provides high-level company coverage information and says complete written terms are provided with proposals. For an actual commercial award, compare the project-specific written warranty and contract exhibits; do not extend a webpage summary beyond those terms.

Route insurance, liens, bonds, and contract language to specialists

The owner, insurance adviser, lender, and South Carolina construction counsel should set insurance limits, additional-insured requirements, waivers, indemnity, performance security, payment security, and risk allocation for the actual project. A generic solar checklist cannot determine the right form or amount.

South Carolina’s mechanics’ lien statute provides lien rights and procedures for qualifying labor and materials used to improve real estate, along with notice, filing, release, and bond provisions. That makes payment documentation and closeout planning material, but it does not justify copying a universal waiver form from another project or state.

Ask counsel to reconcile the proposal, term sheet, contract, general conditions, scope, drawings, specifications, schedule, price schedule, warranty, commissioning plan, and other exhibits. State which documents are incorporated and their order of precedence. Review payment, retainage, change orders, title, lien releases, indemnity, limits of liability, insurance, bonds or other security if required, casualty, suspension, termination, default and cure, assignment, dispute resolution, and survival.

The proposal is not automatically the final agreement. If the contract deletes, narrows, or contradicts an attractive proposal statement, resolve the conflict in signed documents before award.

Define commissioning, acceptance, and closeout before signing

Permission from the utility, completion of construction, substantial completion, mechanical completion, commissioning, and final acceptance are different milestones unless the contract defines them otherwise. Tie payment and risk transfer only to terms the project team understands.

The acceptance file should identify:

• inspections and signoffs required from the contractor, engineer, authority, utility, owner, and other reviewers;
• pre-energization and functional test scripts, instruments, witnesses, data, and pass/fail criteria;
• meter, monitoring, communications, alarm, portal, and data-export verification;
• punch-list classification, correction process, retesting, and completion evidence;
• as-built drawings, final one-line, equipment and settings files, model files, manuals, warranties, registrations, permits, approvals, photographs, and test reports;
• owner training, emergency contacts, shutdown and restart information, and O&M handoff;
• spare parts, keys, labels, credentials, subscriptions, and access rights;
• final payment prerequisites, lien releases, warranties, and record retention; and
• the person authorized to sign final acceptance.

DOE’s federal distributed-energy procurement overview separates RFP requirements and evaluation from design and construction, commissioning and acceptance, and continuing O&M, repair, and replacement. Private South Carolina contracts are different, but the lifecycle separation is useful: the award file should say who owns every duty after the array is energized.

Use a same-scope matrix and choose an honest outcome

Maintain one row per decision field and one column per bidder. Add evidence, status, reviewer, variance from the owner brief, cost or schedule effect where supportable, and required clarification. Do not hide a failed gate inside an average score.

Outcome	Use it when	Required record
Advance to diligence	Scope is comparable and material open items have owners and resolution paths	Approved matrix and diligence list
Request best-and-final clarification	A limited set of answerable gaps prevents comparison	Identical clarification request and response deadline for affected bidders
Redesign or rebid	Owner inputs, system basis, site constraints, or risk allocation changed materially	Revised owner brief and superseded-version log
Remove an alternate	Optional storage, roofing, EV, or other scope is not yet decision-ready	Revised base scope and model
Pause	Rights, licensing, roof, structure, electrical capacity, utility path, economics, or approvals are unresolved	Written issue owner and restart condition

Red flags include refusal to disclose source inputs or model assumptions; mismatched design and financial files; a net price with no gross cash price; unnamed legal entities; unverifiable license evidence; broad allowances; equipment substitutions with no approval rule; “turnkey” paired with material exclusions; a tax result stated as certain; utility approval treated as automatic; no change-order authority; a schedule without dependencies; warranty labels without written terms; and final payment due before testable closeout.

If your team has the owner brief, proposals, utility data, site records, and open-question list, Sunburst’s commercial solar service is the relevant project path. You can request a commercial proposal review focused on making the scope and evidence comparable before your organization decides.

Hold Sunburst to this checklist too

If you are running a comparison, invite us into it and apply every item above to our submission: named legal parties and licenses, design maturity and equipment models, production evidence with its limits stated, a gross-cash price bridge, schedule logic rather than a promised date, and defined commissioning and acceptance. A proposal that cannot survive your own checklist does not deserve the award — ours included.

What Sunburst brings to a commercial bid is a South Carolina construction team rather than a sales channel: 30+ years of combined experience, projects delivered from Daniel Island across the state, including commercial solar in Myrtle Beach and Hanahan, utility interconnection filed in-house, and a published lifetime full-system and roof-penetration warranty on the work.

Use the supporting guides while you evaluate: cost drivers, ROI modeling, interconnection evidence and closeout requirements. Our commercial solar service and city pages show where and how we work. Request a commercial assessment to receive a bid written to this standard.

Frequently asked questions

What should a commercial solar proposal include?

It should identify the legal parties, owner inputs, site rights, load and tariff, design basis, DC and AC capacities, equipment, production model, physical scope, gross cash price, alternates, allowances, exclusions, payment and change-order rules, schedule responsibilities, utility and permit work, financing and tax assumptions, warranties, commissioning, acceptance, and closeout. The contract and exhibits must reconcile with the proposal.

Is price per watt enough to compare commercial solar bids?

No. It becomes useful only after bidders quote the same DC capacity definition and complete scope. Roof, structural, electrical, civil, utility, storage, financing, exclusions, and owner costs can make two price-per-watt figures incomparable. Normalize the gross solar-only cash scope first.

Should proposals show both kWdc and kWac?

Yes. They describe different sides of the design and help reviewers understand inverter loading, clipping treatment, equipment, interconnection, and production assumptions. The proposal should also reconcile both capacities to the layout, one-line, equipment schedule, and model.

Is a production estimate a contract commitment?

Not by itself. A model is an estimate based on stated inputs. A contractual commitment exists only when signed terms define the metric, measurement method, exclusions, duration, notice, correction, remedy, and obligor. Review the exact exhibit with counsel.

Who should verify a South Carolina solar contractor’s license?

The owner or procurement team should verify the exact legal entity through South Carolina LLR and have counsel confirm that its classification, group, and status fit the proposed role and project. Do not rely on a salesperson’s name, another affiliate, or an unnamed subcontractor.

How should tax credits appear in a proposal?

Show the gross project price first. Put tax assumptions in a separate schedule naming the taxpayer, provision, source date, basis, timing, eligibility assumptions, annual usability, documentation owner, and downside case. A qualified tax professional should approve the actual treatment; a proposal should not present a percentage as automatic cash value.

What is the difference between utility approval and final acceptance?

Utility authorization addresses the utility’s interconnection requirements. Final acceptance is an owner-contract milestone that may also require commissioning, monitoring verification, training, as-builts, warranties, punch-list completion, lien releases, and other closeout evidence. Define both separately.

When should a business pause an award?

Pause when the team cannot verify site or utility rights, required licenses, roof or structural feasibility, electrical or interconnection path, comparable scope, gross price, critical exclusions, contract precedence, financing or tax assumptions, or acceptance criteria. Record the issue owner and restart condition rather than accepting an unpriced risk by default.

Sources and methodology

This checklist was researched and primary sources were rechecked on August 10, 2026. It is a procurement framework, not engineering, utility, tax, insurance, accounting, or legal advice. Project documents, current agency and utility requirements, and qualified advisers control the actual decision.

• U.S. Department of Energy: customizable on-site PV technical specifications
• U.S. Department of Energy: federal on-site distributed-energy procurement options
• NREL System Advisor Model: residential and commercial financial model
• IRS: Clean Electricity Investment Credit, Notice 2025-42, clean-energy cost recovery, and Form 3468 instructions
• South Carolina Department of Revenue: Revenue Ruling 24-2
• South Carolina contractor-licensing law, LLR license verification, Building Codes Council adoption, and mechanics’ lien law
• Dominion Energy South Carolina: Solar for Your Business and technical resources
• Santee Cooper: Solar for Business
• Federal Trade Commission: Environmental Claims Summary of the Green Guides