NABCEP PVTS common mistakes
NABCEP PVTS · Understand the traps and how to avoid them.
Writing the proposal around the lowest first-year price per watt instead of building the value case around lifecycle cost of energy, offset percentage, and the customer's actual bill, so the sales presentation collapses the moment a competing bid quotes a cheaper gross number.
Candidates come from installation or design backgrounds and default to quoting system size and price per watt because that is how they talk to peers; they have not practised translating a production estimate into a 25-year levelised cost of energy or a monthly bill comparison, so the customer's decision criteria are never addressed.
What to do instead
Before writing any proposal, calculate and present three numbers side by side: current annual utility spend, projected post-solar annual utility spend, and the levelised cost of energy of the proposed system over its expected life. Build a one-page value summary that leads with the offset percentage and cash-flow chart, and keep price per watt as a supporting line item rather than the headline. Rehearse a two-minute script explaining why the cheaper bid may have a lower production estimate or weaker warranty.
Treating the site assessment as a formality and submitting a proposal with a production estimate based only on satellite imagery, without verifying shade sources, roof condition, structural span, or available electrical capacity on site.
Remote design tools make it easy to produce a plausible layout quickly, and candidates under time pressure skip the physical visit or perform it without a checklist, so obstructions such as a future tree, a plumbing vent cluster, or a 100 A service with no space for a supply-side connection are discovered only at installation.
What to do instead
Use a written site survey checklist covering roof covering and age, rafter size and spacing, all shade casters with compass bearing and height, main panel busbar rating, main breaker rating, available breaker spaces, meter location, and utility interconnect constraints. Photograph every item and record measurements in the file. Where a structural or electrical question remains open, state the assumption explicitly in the proposal and price the remediation rather than ignoring it.
Producing a single annual production number with no stated modelling assumptions, so the customer and the reviewing engineer cannot tell whether shading, soiling, inverter clipping, or degradation were included.
Candidates memorise that a production estimate is required but not that the estimate is a chain of assumptions; they copy the default values from a design tool without understanding what each loss factor represents, and they do not document them because the tool hides them.
What to do instead
Keep a written assumptions sheet in every proposal file listing irradiance data source, tilt and azimuth, shading loss method, soiling loss, mismatch and wiring losses, inverter efficiency and clipping ratio, and annual degradation rate. Sanity-check the result against a simple rule of thumb for the region and against the customer's last twelve months of consumption. Present a conservative and an optimistic production range rather than a single point value.
Sizing the array to the customer's total annual consumption without checking the utility's net metering or compensation rules, the customer's load profile, or whether the service and interconnection limits cap the system below that size.
Candidates equate offsetting 100 percent of annual kilowatt-hours with a good design, but annual energy matching ignores time-of-use value, export compensation rates below retail, and hard limits such as a 10 kW or 25 kW tier boundary or a 120 percent of service capacity rule.
What to do instead
Obtain the customer's interval or monthly usage data and the current tariff sheet, then model the system under the specific compensation programme that applies. Where export is compensated below retail, size to the daytime load and consider load shifting or storage. Check the utility's interconnection application limits and the service capacity calculation before finalising size, and show the customer the bill impact under the applicable tariff, not a generic net metering assumption.
Presenting financial returns using a single payback figure and a flat electricity escalation rate, omitting financing cost, inverter replacement, module degradation, and the difference between cash and financed purchases.
Candidates learn payback because it is easy to compute and easy to explain, but payback ignores everything after the break-even year and conceals the effect of a loan's interest and dealer fees; escalation assumptions are copied from a generic default rather than the local utility's rate history.
What to do instead
Build a year-by-year cash-flow table covering at least 25 years that includes utility escalation, module degradation, inverter replacement in the appropriate year, O and M, insurance if applicable, loan payments and interest, and end-of-life residual value. Report internal rate of return, net present value at a stated discount rate, and simple payback together, and label the escalation assumption with its source. Present cash and financed scenarios side by side.
Quoting a system price that omits known soft costs such as permit fees, utility interconnection fees, structural engineering, main panel upgrade, trenching, or rapid shutdown equipment, then discovering the omission after the contract is signed.
Candidates build the price from equipment and labour because those are the line items they can see in a design takeoff, while permit and interconnection costs vary by jurisdiction and are not in the design tool; the omission surfaces only when the permit package is assembled.
What to do instead
Maintain a jurisdiction-specific soft-cost checklist and add every line to the estimate before the proposal is issued: permit and inspection fees, interconnection application fee, engineering stamps, panel upgrade or derate, trenching and conduit, rapid shutdown devices, monitoring gateway, and commissioning. Where a cost is genuinely unknown, carry a stated allowance in the proposal and disclose it as an allowance. Reconcile the estimate against actual invoices after each job and update the checklist.
Explaining incentives from memory without confirming current programme status, cap, step-down schedule, or eligibility, and implying the customer is guaranteed a tax credit or rebate.
Incentive rules change annually and vary by utility, state, and taxpayer status; candidates rely on training material or last year's project, and the sales pressure to present an attractive number discourages them from checking the authoritative source.
What to do instead
Verify each incentive against the primary source, meaning the relevant tax authority guidance, the state energy office programme page, and the utility's current tariff or rebate schedule, and record the date checked and the source in the file. State eligibility conditions and any step-down or cap in the proposal, and use language that describes an expected benefit subject to the customer's tax situation rather than a guarantee. Recommend the customer confirm tax matters with a qualified adviser.
Handling a customer objection by repeating the original pitch louder, or by conceding a discount, instead of diagnosing the concern behind the objection.
Candidates rehearse feature lists rather than question sequences, so when a customer says the price is too high or they want to wait, the candidate hears a price objection and reacts with a price response, when the real concern may be roof longevity, moving house, or distrust of the production estimate.
What to do instead
Practise a structured objection response: acknowledge, ask a clarifying question to locate the concern, answer the specific concern with evidence, then confirm the answer resolved it. Prepare evidence for the five most common objections, including a production guarantee explanation, a roof warranty and removal-and-reinstall policy, a home-sale transferability statement, and a financing comparison. Never discount without removing scope or documenting the reason.
Submitting a proposal or contract that lacks required consumer protection disclosures, a clear scope of work, change-order terms, or a production guarantee with defined exclusions, or that misstates the customer's cancellation rights.
Candidates focus on the technical content and treat paperwork as an administrative afterthought, and disclosure requirements differ by state and by whether the transaction is a sale, lease, or power purchase agreement, so generic templates borrowed from another jurisdiction are often non-compliant.
What to do instead
Build a contract checklist that is reviewed per jurisdiction and per transaction type, covering scope and exclusions, schedule, payment milestones, change-order procedure, roof penetration and weatherproofing warranty, production guarantee method and exclusions, cancellation and rescission rights with the required notice, and disclosure of the salesperson's role. Have the template reviewed by counsel familiar with the state's home solicitation and solar consumer protection rules, and confirm every proposal carries the required disclosures before it leaves the office.
Failing to document the customer's goals, constraints, and decision criteria during the qualification conversation, so the proposal addresses the salesperson's priorities rather than the customer's and follow-up has no agreed next step.
Candidates treat qualification as a data-gathering step for system sizing, collecting kilowatt-hours and roof pitch but not motivation, timeline, budget range, decision makers, or competing quotes, and they leave the conversation without a scheduled commitment.
What to do instead
Use a written discovery form that records why the customer is considering solar, planned roof work or move date, budget and financing preference, who else is involved in the decision, what other quotes they hold, and the specific criteria they will use to choose. Summarise those criteria back to the customer, map each proposal section to one of them, and close every conversation with a dated next step such as a proposal review call or a reference site visit.