What payback period means
Payback period is the point where cumulative savings from solar generation meet or exceed the system cost. It is a comparison of cash out today against avoided utility spend over time. The result is illustrative only, because actual rates, consumption, and system performance vary by site and by household use.
What drives the estimate
The calculator uses the monthly bill and electricity rate to infer consumption, then applies system size, sun hours, and a performance factor to estimate production. Bill escalation and panel degradation are included as simple annual assumptions. Monthly savings are capped at the monthly bill, so the estimate stays conservative rather than optimistic.
Using the calculator
Enter your monthly bill, system cost per kilowatt, system size, peak sun hours, and performance factor. If you want a suggested size, start with your bill and rate; the tool will propose a size and set it for you until you drag the slider manually. You can also open the calculator on the homepage and enter the same inputs there. Open the solar payback calculator
Talk to our team
If you want a site-specific review of your bill, roof or ground area, and backup needs, share your last bill or your monthly consumption. Our team will turn those inputs into a clearer estimate than the illustrative figure from the homepage tool.
Frequently asked questions
What inputs does the calculator need?
Monthly bill, system size, electricity rate, sun hours, and system cost per kW — defaults are ₱11/kWh, ₱80,000/kW, 4.5 sun hours, and 0.80 performance factor.
Why is my savings capped at my bill?
An oversized system cannot save more than you currently pay — the cap keeps estimates conservative instead of inflated.
What scenarios can I compare?
Cash purchase, loan, solar lease, and PPA — with NPV, IRR, monthly payments, and a 25-year cash-flow projection.
Is the result a formal quote?
No — it is an illustrative estimate. A formal quote with exact components and warranties follows a site assessment.
Ready for a site-specific estimate?
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