Solar Panel Calculator Philippines
Estimate the solar system size, number of panels, potential energy generation, panel area, and preliminary grid-tied installation budget for a home in the Philippines.
Electricity & Solar Inputs
Enter your electricity use and preferred solar-system assumptions.
Panel Dimensions
Used only to estimate the surface area occupied by the solar panels.
Estimated Installation Budget
Editable preliminary 2026 planning rates for a grid-tied solar installation without battery storage.
Existing or Proposed Solar Array
Enter the number and wattage of panels to estimate the array size, theoretical generation and preliminary installation budget.
This Solar Panel Calculator helps homeowners in the Philippines estimate the solar system size needed based on monthly electricity consumption. It can estimate the required PV capacity in kWp, number of solar panels, potential electricity generation, approximate panel surface area, and a preliminary grid-tied solar installation budget.
The calculator is intended for early planning and comparison of solar options. Actual solar-system design should still be checked by a qualified solar installer or electrical professional because roof orientation, shading, equipment specifications, electrical conditions and other site-specific factors affect system performance.
How to Use the Solar Panel Calculator Philippines
- Enter your monthly electricity consumption in kWh. You can normally find this on your electricity bill.
- Select the percentage of your electricity consumption you want solar power to target.
- Enter the peak sun hours to use for preliminary sizing. The calculator provides 4.5 hours/day as its default Philippine planning value.
- Select the wattage of the solar panel you are considering.
- Choose whether to apply a system-loss allowance for preliminary real-world planning.
- Enter the panel dimensions if you want an approximate total panel surface area.
- Review the estimated system size, panel quantity, electricity generation and preliminary installation budget.
How Is Solar System Size Calculated?
A preliminary residential solar calculation starts by converting monthly electricity consumption into average daily electricity consumption.
Monthly Electricity Consumption ÷ 30
The daily electricity requirement targeted for solar is then divided by the selected peak sun hours.
Daily Solar Energy Target (kWh/day) ÷ Peak Sun Hours (hours/day)
If a system-loss allowance is selected, the calculator increases the planning PV requirement before determining the number of panels.
Theoretical PV Requirement ÷ (1 − System Loss Percentage)
The required number of solar panels is then calculated from the selected panel wattage and rounded up to a whole panel.
Example: Solar Panels for 350 kWh Monthly Consumption
Example Calculation
Suppose a household consumes 350 kWh/month and wants to target 100% of that average consumption using a preliminary 4.5 peak-sun-hour assumption.
Average daily consumption:
350 ÷ 30 = 11.67 kWh/day
Theoretical PV requirement:
11.67 ÷ 4.5 = approximately 2.59 kWp
Using 550 W panels with no additional system-loss allowance:
2.59 ÷ 0.55 = approximately 4.71 panels, which is rounded up to 5 solar panels.
Five 550 W panels provide an installed nominal array capacity of 2.75 kWp.
What Does kWp Mean in a Solar System?
kWp means kilowatt-peak. It describes the nominal rated power of a solar PV array under specified test conditions.
For example, ten 550 W solar panels have a combined nominal capacity of:
A 5.50 kWp array does not mean that it will continuously produce 5.50 kW throughout the day. Actual output changes with sunlight, temperature, shading, orientation, equipment performance and other conditions.
What Are Peak Sun Hours?
Peak sun hours are a convenient way of expressing the amount of usable solar energy available during a day. They are not simply the number of daylight hours.
For preliminary residential sizing, this calculator starts at 4.5 peak sun hours per day. The Philippine Department of Energy has used approximately 4.5 to 5 peak sun hours in residential solar sizing guidance.
Actual solar resources vary by location, season, weather, roof orientation and shading, so a project-specific assessment should be used before final system design.
How Many Solar Panels Do I Need?
The number of panels depends primarily on your electricity consumption, desired solar coverage, available solar energy and the wattage of each panel.
Higher-wattage panels can provide more nominal PV capacity per panel. However, panel efficiency, physical dimensions, roof layout, manufacturer specifications and system compatibility should also be considered.
| Number of Panels | Panel Rating | Nominal PV Capacity |
|---|---|---|
| 4 panels | 550 W | 2.20 kWp |
| 6 panels | 550 W | 3.30 kWp |
| 8 panels | 550 W | 4.40 kWp |
| 10 panels | 550 W | 5.50 kWp |
| 12 panels | 550 W | 6.60 kWp |
| 20 panels | 550 W | 11.00 kWp |
This table shows nominal panel capacity only. It does not represent a recommendation for a particular property.
What Is the System Loss Allowance?
Real solar systems do not reproduce their nameplate output under every operating condition. Temperature, inverter conversion, wiring, dirt, shading and other factors can reduce energy production.
The calculator therefore allows you to apply an optional system-loss allowance. Selecting 0% keeps the calculation as a simple theoretical sizing estimate, while selecting an allowance increases the preliminary PV capacity required to target the entered electricity use.
How Much Electricity Can Solar Panels Generate?
The calculator estimates theoretical daily solar energy by multiplying installed PV capacity by the entered peak sun hours.
Installed PV Capacity (kWp) × Peak Sun Hours
For example, a 5.50 kWp array using 4.5 peak sun hours gives:
This is a theoretical planning estimate. The calculator separately shows an allowance-adjusted estimate when a system-loss percentage is entered.
Solar Panel Cost Calculator Philippines
The calculator also provides a preliminary budget range for a grid-tied solar system without battery storage. The default planning range is ₱50,000 to ₱70,000 per kWp, and both values are editable.
Installed PV Capacity (kWp) × Estimated Cost per kWp
For example, a 3.30 kWp system using the default planning rates gives:
Low preliminary estimate:
3.30 kWp × ₱50,000/kWp = ₱165,000
High preliminary estimate:
3.30 kWp × ₱70,000/kWp = ₱231,000
Actual solar quotations can vary considerably depending on panel and inverter brands, mounting system, roof condition, electrical works, project location, access, permits, net-metering scope, warranties and installer inclusions.
Does the Solar Cost Estimate Include Batteries?
No. The calculator's installation budget is intended as a preliminary estimate for a grid-tied solar PV system without battery storage.
Battery sizing depends on factors such as required backup duration, nighttime consumption, critical loads, usable battery capacity, battery chemistry, inverter configuration and allowable depth of discharge. Because of these variables, battery sizing should be assessed separately.
How Much Roof Space Do Solar Panels Need?
The calculator multiplies the number of panels by the entered panel length and width to estimate the total panel surface area.
Number of Panels × Panel Length × Panel Width
This is not the same as the final required roof area. Actual installation needs may be larger because of panel spacing, roof edges, access paths, obstructions, mounting clearances and the final array layout.
What Can Affect Actual Solar Panel Output?
Two homes with the same nominal solar-system size can produce different amounts of electricity. Important factors include:
- Geographic location and local solar resource
- Roof orientation and panel tilt
- Shading from trees, buildings and other obstructions
- Cloud cover and seasonal weather
- Solar panel operating temperature
- Panel soiling and maintenance
- Inverter efficiency
- Electrical and wiring losses
- Panel degradation and equipment condition
The calculator should therefore be used for preliminary planning rather than as a guaranteed energy-production forecast.
Can I Use My Monthly Electricity Bill Instead of kWh?
For solar-system sizing, monthly electricity consumption in kWh is more useful than the peso amount of the bill.
Electricity bills can change because of tariffs, taxes, adjustments and other charges even when energy consumption is similar. Check your bill for the actual kWh consumption and enter that value into the calculator.
Grid-Tied Solar and Net Metering in the Philippines
A grid-tied solar system operates together with the electric utility grid. When a qualifying system exports excess renewable electricity to the distribution network, Philippine net-metering rules may allow eligible customers to receive credits subject to applicable regulations and utility requirements.
The amount of solar electricity generated is not necessarily the same as the amount of electricity that will offset your bill peso-for-peso. Consumption timing, exported energy, applicable rates and the approved system arrangement all matter.
Consult your distribution utility and qualified solar installer regarding current net-metering requirements before installation.
Solar Panel Calculator Philippines FAQs
How do I calculate how many solar panels I need?
Start with your average daily electricity consumption, determine the portion you want solar to cover, divide that energy requirement by the applicable peak sun hours, and then divide the required PV capacity by the wattage of each panel. The final panel quantity is rounded up to a whole panel.
How many solar panels do I need for 350 kWh per month?
Using a simple preliminary calculation with 4.5 peak sun hours, 100% target coverage and 550 W panels, 350 kWh/month requires about 2.59 kWp theoretically. This corresponds to approximately five 550 W panels before applying any additional system-loss allowance.
What size solar system do I need for my home?
The appropriate size depends on your electricity consumption, desired solar coverage, solar resource, roof conditions, shading, equipment and system design. Use your actual monthly kWh consumption as the starting point for this calculator.
What does a 5 kWp solar system mean?
A 5 kWp solar system has approximately 5 kilowatts-peak of nominal PV panel capacity. It does not mean the system continuously produces 5 kW throughout every daylight hour.
How many kWh can a 5 kWp solar system produce per day?
Using 4.5 peak sun hours as a simple example, 5 kWp × 4.5 gives a theoretical estimate of 22.5 kWh/day. Actual production may be lower or higher depending on site and operating conditions.
Is 4.5 peak sun hours accurate for the Philippines?
It is useful as a preliminary planning assumption. Philippine DOE residential solar guidance has referenced approximately 4.5 to 5 peak sun hours. Actual solar resources vary by location, season, weather, orientation and shading.
Does a solar system completely eliminate my electricity bill?
Not necessarily. Solar production varies throughout the day and year, while electricity consumption also changes. Grid charges, exported-energy treatment, applicable tariffs and other billing components may still apply.
Does this solar calculator include battery storage?
No. The calculator focuses on preliminary PV array sizing and a grid-tied installation budget. Battery capacity requires separate calculations based on loads, backup duration and battery-system specifications.
Does the estimated solar cost include net-metering fees?
Not specifically. The displayed cost is a preliminary planning estimate based on editable cost-per-kWp assumptions. Actual quotations should clearly state whether permits, utility applications, net-metering work and other project costs are included.
Can I use this calculator for a commercial solar system?
It can provide a rough preliminary energy estimate, but commercial systems normally require more detailed load analysis, interval consumption data, electrical assessment, structural review and professional PV-system design.
Planning a Construction or Home Improvement Project?
Use our other free Philippines construction calculators to prepare preliminary material and project estimates.