Net metering is the most misunderstood part of Philippine solar, and the misunderstanding costs people money. It does not pay you retail for what you export. Understanding the difference changes how you size a system.
Under Republic Act 9513, households with systems up to 100 kW can export surplus to the grid. Exports are credited at the blended generation rate, roughly ₱6.50 per kWh in Meralco territory and ₱4.50 to ₱5.50 in the Visayas and Mindanao, not the retail rate of ₱14.7833. A kilowatt-hour you use yourself is therefore worth roughly twice one you export.
What a kWh is worth to you
Change any box. The result updates as you type.
Planning estimate. The rate box is prefilled with a regional average; the figure on your own bill is the one that matters. Power is draw while running, not while switched on.
How the credit actually works
Your meter records energy flowing both ways. At the end of the billing cycle the utility nets your import against your export. If you imported more than you exported, you pay for the difference at retail. If you exported more, the surplus becomes a peso credit at the generation rate, carried to the next bill.
The credit does not expire monthly but it also does not become cash. It offsets future bills. A household that consistently exports more than it imports accumulates credit it may never fully use, which is another reason oversizing is a poor investment.
Why the export rate is lower
The retail rate you pay includes generation, transmission, distribution, system loss, taxes and universal charges. When you export, you are supplying energy only. You are not supplying poles, wires, or the grid operator services, so you are credited for the energy component alone. That is the logic, and it is consistent across every distribution utility.
The practical consequence is the single most important sizing rule in Philippine residential solar: match the array to your daytime consumption, not your monthly bill. Every kilowatt-hour consumed on site is worth full retail. Every kilowatt-hour exported is worth less than half that.
The application process
- Choose a DOE-accredited installer. Interconnection goes more smoothly and the paperwork is familiar to them.
- Submit the net metering application to your distribution utility with the system design, single-line diagram, equipment specifications and inverter certification.
- Distribution impact study. The utility checks that your system will not destabilise the local circuit. Small residential systems normally clear this without issue.
- Sign the net metering agreement once approved.
- Meter replacement. The utility installs a bidirectional meter capable of recording flow in both directions.
- Commissioning and energisation. Only after this may the system legally export.
Timelines vary by utility and are commonly measured in weeks rather than days. A reputable installer handles the whole sequence as part of a turnkey quote, and if a quote excludes the net metering application, that is a gap worth pricing.
What net metering does not do
- It does not keep your lights on during a brownout. Grid-tied inverters are required to disconnect when the grid fails. Backup requires a battery and a hybrid inverter.
- It does not zero your bill. Fixed charges remain, and night consumption is always imported at retail.
- It does not pay cash. Surplus becomes bill credit, not income.
- It does not cover systems above 100 kW under the residential net metering programme.
Realistic bill reduction
A grid-tied system without storage typically removes 40 to 80 percent of a bill, not all of it. Where a household lands in that range depends almost entirely on how much of the production is consumed during daylight. A house occupied through the afternoon with aircon running sits at the top; an empty house sits at the bottom.
Run your own numbers on the solar self-consumption calculator and the export value calculator before accepting any payback figure from an installer.