Solar Calculators & Tools
Five free calculators for planning solar in the Philippines — size, cost, savings, loan payments, and battery backup. No sign-up, no sales pitch, and every assumption behind the numbers is published below.
Cost & savings
Size a system from your bill and city, and see installed cost, monthly savings, payback, and 25-year net savings.
Financing
Compare GSIS Ginhawa, Pag-IBIG, bank loans, and 0% installer installment on monthly payment and total interest.
Backup power
Get the recommended battery capacity in kWh for backup during brownouts or overnight, from four simple inputs.
Build & price
Build a real system from panels, inverter, battery, and add-ons sold in the Philippines. See price range, payback, and a compatibility check.
Quotes
Ready for real numbers? Enter your bill and we will help you find quotes — no spam, no phone number needed.
Which one do you need?
Most people arrive with one of five questions. Start with the tool that matches yours rather than working through all of them:
- What size do I need, and what will it cost?
- Solar Panel Calculator
- If I borrow, what does it cost per month and in total interest?
- Solar Financing Calculator
- How many kWh of battery do I need to ride out an outage?
- Battery Size Calculator
- Which actual components go together, and do they match?
- Solar System Builder
- What will installers actually charge me?
- Get free quotes
The order that actually works
Size first, then price, then money. Doing it the other way round — picking a budget and seeing what it buys — is how people end up with a system too small to move their bill, which is the single most common regret we hear.
- Work out the size from your bill, not from your roof or your budget. A system is sized to the electricity you actually use.Solar Panel Calculator
- Check the installed cost against the market band below before you take a quote seriously in either direction — too cheap is a warning, not a bargain.
- Decide whether you need a battery at all. A grid-tied system with net metering is far cheaper per peso saved. A battery buys you outage cover, not savings.Battery Size Calculator
- Price the borrowing separately from the system. A low monthly payment over a long term can cost more than the panels did.Solar Financing Calculator
- Get real quotes and compare them against what you calculated. Get free quotes
The numbers every calculator here runs on
These are the assumptions, published rather than buried. They come from one file that every tool on the site reads, so a figure cannot say one thing on a calculator and another in a guide.
- Installed cost
- ₱45,000–₱75,000 per kWTypical installed price across the market, with ₱55,000 as the mid case. A 5 kW system therefore lands around ₱225,000–₱375,000. Full price list by size
- Generation
- 120 kWh per kW per monthMetro Manila’s 4.7 peak sun-hours across 30 days, already derated by 85% for inverter losses, wiring, soiling and heat. Cities range from 4.3 to 5.2 sun-hours, which moves this by roughly −9% to +11%.
- Electricity rate
- ₱14.74 per kWhMeralco all-in residential, read from the latest verified month rather than hardcoded. How the rate is built
- Savings
- About ₱1,300 per kW per monthAssumes high self-consumption. Under Meralco net metering, power you export is credited at generation cost only, roughly ₱5–7/kWh, so savings depend on using what you generate as you generate it.
- Battery storage
- ₱13,000–₱23,000 per usable kWhUsable, not nameplate — lead-acid gives up about half its nameplate, so comparing chemistries on nameplate flatters the cheaper one. Battery price guide
- Largest priced system
- 12 kWAbove this we stop quoting a price rather than extrapolating one. A bigger system is a custom job and needs a real survey.
What a calculator cannot tell you
Every number here is an estimate built from published market figures, and it is worth being clear about where that stops. A calculator has never seen your roof. It does not know:
- Whether your roof can take the load. Age, sheet thickness, purlin spacing and corrosion all decide what can be mounted and whether it survives a typhoon. That needs someone on the roof.
- How much shade you get, and when. A single tree or a neighbour’s new second storey can cost more output than the difference between two panel brands.
- What your utility will approve. Net metering terms, transformer capacity and the application queue vary by utility and by area. Net metering explained
- What your installer will actually charge. Quotes vary widely for the same specification, which is why the last step is always real quotes rather than an estimate.
Use these to arrive at a conversation informed rather than to replace one. If a quote sits far outside the bands above in either direction, that is worth asking about — and ourinstaller checklistcovers the questions that tend to surface why.