A single payback number is not enough evidenceCopy section link
A payback period is a result, not an explanation. Before relying on it, ask what assumptions produced it: system cost, annual generation, self-consumption, export value, current tariff, tariff escalation, degradation, downtime, financing cost, and maintenance. If the supplier cannot show the model, the claim is not yet decision-ready.
Export-heavy savings assumptions need extra scrutiny under net billingCopy section link
Under Pakistan's current net-billing logic, units used onsite and units exported to the grid should not be treated as identical. The net-billing guide covers the accounting split. If a savings claim assumes a large share of generation is exported at an optimistic value, the proposal may overstate economic value.
Generation claims should match the site, not a perfect templateCopy section link
Solar production depends on roof orientation, tilt, shading, temperature, dirt, inverter clipping, downtime, and maintenance. A generic annual unit estimate may be reasonable for early screening, but it is not enough for approval. Buyers should ask whether the model reflects the actual site and whether monthly generation is shown.
Savings can be overstated when operating costs are ignoredCopy section link
A clean savings slide often leaves out costs that appear later: cleaning, preventive maintenance, monitoring subscriptions, inverter service, battery replacement, insurance, financing charges, and roof or electrical upgrades. These may not destroy the business case, but they should be visible before the buyer approves the project.
Guaranteed language should point to contractual termsCopy section link
Words like guaranteed, assured, fixed, and risk-free should make a buyer slow down. If savings are truly guaranteed, the contract should define the baseline, measurement method, exclusions, remedy, duration, and evidence required. If not, treat the phrase as sales language rather than financial certainty.
Savings-claim red flag checklist
- ✓Ask for the tariff, export value, self-consumption, and generation assumptions behind the savings number.
- ✓Compare aggressive, base, and conservative cases instead of relying on one payback period.
- ✓Check whether downtime, degradation, cleaning, O&M, inverter replacement, and financing cost are included.
- ✓Treat guaranteed-sounding savings language carefully unless the supplier has written performance terms.
Frequently asked questions
Usually no. They are projections based on generation, tariff, export, usage, downtime, and cost assumptions unless a contract explicitly creates a performance guarantee.
A single short payback number with no tariff, export, self-consumption, degradation, or downtime assumptions shown.
Put both on the same generation, tariff, export, self-consumption, and cost basis first. Then compare the economics.
Sources and notes
Continue with adjacent guides
Buyer action
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