Bills & savings
Bill Mo, Explained: What Your Electricity Bill Tells You Before Going Solar
Your electricity bill is the best starting point for solar. Learn which numbers matter, what they miss, and how to turn twelve months of bills into a useful assessment.
A high electricity bill gets your attention. But the peso total alone cannot tell you which solar system belongs on your roof. To make a sensible choice, you need to separate how much electricity your household uses, what you pay for it, and when you use it.
The good news? You already have a useful starting document. Here is how to read your bill with a solar assessment in mind, without becoming an electricity-market expert. Bill muna, bago panels.
Start with consumption, not the amount due
Find the electricity consumed during the billing period, usually expressed in kilowatt-hours, or kWh. That measures energy. A 1,000-watt appliance operating continuously for one hour uses 1 kWh. Actual appliances often cycle or change power, so this is a unit example rather than an estimate for your aircon.
Then check the number of billing days. For a fictional household using 450 kWh over 30 days, average consumption is 15 kWh a day. A 33-day bill will naturally cover more days than a 28-day bill. Normalising both to kWh per day helps you compare them fairly.
Understand what the different charges do
Meralco separates electricity generation, transmission, distribution and other regulated charges on the bill. Its explanation also distinguishes the charges it retains from amounts collected for other parties. The proportions change, so treat the bill for your actual month as the reference. [1]
For an initial conversation, divide current-period electricity charges by current-period kWh to get a rough average cost. Exclude an old unpaid balance, a deposit adjustment or an unrelated fee. This rough average is useful context; it is not automatically the value of every solar kWh. Ask your proposal to identify which charges it expects you to avoid.
Look at a year, not your most expensive month
Collect twelve consecutive bills if you can. Put the billing dates, kWh and current-period charges into three columns. Add a short note beside unusual months: visitors stayed, the family travelled, someone started working from home, or an air-conditioning unit was replaced.
This small exercise prevents two mistakes. A one-off hot month should not automatically dictate the system size. A low month when the house was empty should not set your long-term expectations either. If you have only recently moved in, say so; an installer can build a provisional estimate and explain the extra uncertainty.
Fill in the detail your bill cannot show
Two homes can each use 450 kWh a month and need different solar designs. In our fictional example, one home runs an office and aircon during daylight. The other is empty until dinner, then cooks, cools bedrooms and charges devices overnight. The monthly totals hide that difference.
Write a simple weekday and weekend timetable. Note when people are home, when cooling runs, and when washing or pumping usually happens. Use actual meter or monitoring data where available. Do not guess a precise daytime percentage from the monthly bill; an hourly load assessment provides a stronger basis for estimating self-consumption.
Keep savings and export credits separate
Solar used immediately at home can reduce electricity bought from the grid. Approved net-metering exports create a separate bill credit. For Meralco, the export calculation uses its applicable monthly blended generation charge, excluding other generation adjustments, rather than the full retail purchase rate. [2]
That distinction belongs in every savings discussion. Ask to see estimated solar generation divided into electricity used at home, electricity exported and any curtailed output. A single figure called 'solar savings' is difficult to check when its ingredients are hidden. The same bill can support several outcomes depending on when appliances run.
Tell the installer what will change
Last year's bills describe last year's household. A new baby, an additional aircon, an electric vehicle or a home business can change your future load. List likely purchases and their expected schedules, even if you have not chosen a model yet.
Separate committed changes from possibilities. 'We ordered an EV and expect to charge at night' is different from 'we might buy one in five years.' Ask for the base case and a future scenario separately. That keeps today's investment grounded while making room for upgrades where the design supports them.
Bring a small, useful assessment pack
Your first solar conversation becomes more useful with twelve bills, a weekly appliance timetable, the service address and safe ground-level roof photographs. Include your top priority: lower daytime purchases, outage backup, or both. Backup needs a separate discussion about circuits and stored energy.
Quality solar, made simple starts with understanding the household. Share these details with Lightning Energy Philippines and ask for the assumptions behind the proposal. You should leave knowing why a system was suggested, which parts of your bill it can influence, and which questions still need a site visit.
Sources & further reading
Sources used for this guide. Policy and product details should be checked for your particular installation.
- Meralco — Bill Breakdown FAQsAccessed 20 September 2026
- Meralco — Net-Metering Billing FAQsAccessed 20 September 2026
