You can get brownout backup without solar panels. Pair a pure sine wave inverter that has a built-in grid charger with a deep-cycle battery. A 12 V 1000 W toroidal unit with a 15 A AC charger lists at ₱6,000, and adding a 100 to 200 Ah battery brings the setup to about ₱13,800 to ₱20,600, before wiring and installation. It charges from BILECO or LEYECO while the power is on and takes over when the power goes off. With a fridge, two fans, LED lights and Wi-Fi running, that's about 2.5 to 5 hours of backup, depending on the battery.
It won't run an aircon or cut your bill. It's just a cheap way to keep the fridge cold and fans going through an evening rotating brownout, like the 5 pm to 9 pm window NGCP warned the Visayas about on 26 August (GMA News). And if you buy the right inverter, you can add panels later.
Prices were checked on 25 October 2026 on each seller's own website. Listing a product isn't an endorsement, and Solar Leyte earns nothing from these links. Nothing here is a MACC price or package.
What you're actually buying
The setup has three jobs: store power (battery), turn 12 V DC into 220 V AC (inverter) and refill the battery from the grid (charger). Many cheap inverters skip the charger, so look for "AC charger" or "UPS" mode on the listing.
Part | What to look for | Example listing (25 Oct 2026) | Price |
|---|---|---|---|
Inverter with grid charger | Pure sine wave, 220 V 60 Hz, AC charger, AVR | Zamdon 12V 1000W toroidal (Anak Araw): 15 A AC charging, 145–275 V AC input, built-in AVR, lead-acid or lithium | ₱6,000 |
Inverter, no charger listed | Ask the seller about grid charging | One Solar 12V 1000W pure sine wave, wall type (Beyond Power) | ₱6,200 |
Off-grid hybrid (solar-ready) | Built-in MPPT for panels later | One Solar 12V 1200W with 40 A MPPT (Beyond Power) | ₱10,100 |
Lead-acid battery | Deep-cycle, not a car battery | Solar Home 12V 100Ah (Beyond Power) / Solar Homes 12V 100Ah gel (LakaSolar) | ₱7,800 / ₱6,500 |
Lead-acid battery, bigger | Deep-cycle | Solar Home 12V 200Ah (Beyond Power) | ₱14,600 |
LiFePO4 battery | Matches the inverter voltage | Higee 12.8V 120Ah, about 1.54 kWh (Beyond Power) | ₱13,400 |
Beyond Power's page for the One Solar wall-type unit says to "pair with a solar charge controller for PV charging" and lists the full specs as "contact us", so ask whether it charges from the grid before you buy it for this job.
Pure sine wave vs modified sine wave
Grid power is a smooth sine wave. A modified sine wave inverter makes a stepped, blocky copy of it, which motors don't like.
Samlex, an inverter maker, explains why: a modified sine wave carries extra high-frequency harmonics, which cause "higher heating effect in motors". On a pure sine wave, motors "run faster, quieter and cooler". Samlex also lists devices that may misbehave or get damaged on modified sine wave: fan speed controls, clocks in appliances, laser printers and some rechargers (Samlex America).
At home the motors are the fridge compressor, electric fans and a water pump, so buy pure sine wave. It isn't always pricier: at Panther, the PSI 1000 pure sine wave inverter (1000 VA, 12 V) lists at ₱19,500 and the PPI 2000 modified sine wave (2000 VA, 12 V) at ₱24,500 (Panther PSI 1000, Panther PPI 2000). Neither Panther listing mentions a grid charger.
How many hours will it last?
We used the two load lists from our battery sizing guide, which are built from DOE energy labels and Meralco's tested-appliance tables:
- Basic load, 86.4 W: one 16-inch stand fan, two 9 W LED bulbs and a Wi-Fi router.
- Essentials with fridge, 190.3 W: an 8 cu ft inverter fridge, two stand fans, four LED bulbs and the router.
Worked example (our estimate, not a test). Our assumptions:
- Usable capacity: 50% of a lead-acid battery and 80% of a LiFePO4 battery. These are the depths of discharge in Victron's published cycle ratings, explained in the next section.
- Inverter losses: 87% efficiency, from One Inverter's spec for its HI series of low-frequency inverters (One Inverter).
- Idle draw: 13 W for a 12 V inverter and 17 W for a 24 V one. Samlex's SWI-1100 manual lists idle current under 1.1 A at 12 V and under 0.7 A at 24 V (Samlex manual (PDF)).
So: hours = usable Wh × 0.87 ÷ (load W + idle W).
Battery (listed price) | Usable energy | Basic load (86.4 W) | Essentials with fridge (190.3 W) |
|---|---|---|---|
12V 100Ah lead-acid (₱7,800) | 600 Wh | about 5.2 hours | about 2.6 hours |
12V 200Ah lead-acid (₱14,600) | 1,200 Wh | about 10.5 hours | about 5.1 hours |
12.8V 120Ah LiFePO4 (₱13,400) | about 1,229 Wh | about 10.7 hours | about 5.3 hours |
25.6V 120Ah LiFePO4 (₱33,600, needs a 24 V inverter) | about 2,458 Wh | about 20.7 hours | about 10.3 hours |
The chart below shows the same estimates side by side.
Expect a bit less from lead-acid: Victron's datasheet shows a gel battery giving about 80% of rated capacity when drained over 5 hours instead of 20 (Victron datasheet (PDF)).
What this means for Leyte and Biliran:
- For a 4-hour evening rotating brownout, a 200Ah lead-acid or a 12.8V 120Ah LiFePO4 battery covers the fridge list with some to spare. A single 100Ah lead-acid battery doesn't.
- For a 13-hour outage like BILECO's 8 August shutdown (5 am to 6 pm, details in the battery guide), only the 25.6V 120Ah option comes close with the fridge running.
- Recharging is cheap. Refilling 1.2 kWh of usable energy costs about ₱23 at BILECO's September 2026 rate of ₱18.93 per kWh (PRESYO-PH), plus charging losses (our calculation). A 15 A charger puts in roughly 190 W, so refilling 1.2 kWh takes about 6 hours.
Lead-acid or LiFePO4?
Lead-acid is cheaper up front; LiFePO4 lasts far more cycles. Victron publishes ratings for both, so we used them as a like-for-like reference:
Victron rating | 12V Deep Cycle GEL | 12.8V LiFePO4 Smart |
|---|---|---|
Cycles at 80% depth of discharge | 500 | 2,500 |
Cycles at 50% depth of discharge | 750 | 5,000 |
Cycles at 30% depth of discharge | 1,800 | n/a |
Design life on float at 30°C | 6 years (12 years at 20°C) | n/a |
Sources: Victron GEL and AGM datasheet (PDF), Victron 12.8V LiFePO4 Smart datasheet (PDF). The Solar Home and Higee batteries above are different brands, so ask the seller for their own cycle ratings.
Two practical points:
- Heat shortens lead-acid life. Victron's float life halves between 20°C and 30°C. Keep the battery shaded and ventilated.
- Match the voltage. A 12 V inverter needs a 12 V (or 12.8 V) battery, not a 25.6 V one.
Will it run my fridge, pump or aircon?
Motors pull a big surge when they start. Samlex's sizing table recommends an inverter rated at 5 times the running watts of a compressor fridge or aircon, and 3 times for a well pump (Samlex manual (PDF)).
Worked example:
- Fridge: if your fridge's sticker says 100 W (an example, so check yours), Samlex's rule points to a 500 W inverter. A 1000 W unit is fine.
- Aircon: a 1 HP inverter aircon rated at 870 W on its DOE label (see the battery guide) would need about 4,350 W by the same rule. Even ignoring the surge, it would drain a 1,200 Wh usable battery in under 1.5 hours.
For aircon through a brownout, look at a full hybrid solar system (grid-tie vs hybrid, hybrid inverter prices).
How it compares with the other brownout options
Option | Listed price range | Charges from | Best for |
|---|---|---|---|
Inverter with charger + battery (this post) | about ₱13,800 to ₱20,600 (12 V examples above) | Grid only, or panels later with a hybrid unit | Fridge, fans, lights, Wi-Fi for an evening brownout |
Power station (EcoFlow, Jackery, BLUETTI) | ₱29,990 to ₱46,900 for 1 kWh units | Grid, car or a solar panel | Renters, no wiring, easy to move (power station prices) |
Generator | See our comparison | Gasoline | Long outages and big loads (generator vs solar) |
Hybrid solar with battery | See our hybrid post | Solar and grid | Cutting the bill and running aircon (hybrid inverter prices) |
Solar-ready shortcut: the One Solar 12V 1200W hybrid with 40 A MPPT (₱10,100) costs ₱4,100 more than the ₱6,000 inverter/charger but lets you add panels later. Its listing only mentions the solar charger, so confirm it also charges from the grid.
Wiring it in safely
- Simplest and safest: plug the fridge, fans and router straight into the inverter's outlets. No house wiring is touched. (Only backing up the modem? A mini DC UPS is enough; see our Wi-Fi backup post.)
- If you want it to feed your house circuits, have a licensed electrician fit a proper changeover or transfer switch. Without one, the inverter can feed power back into the co-op line, the same backfeed danger that generator makers warn about (see our generator post).
- Ventilate lead-acid batteries. Samlex's manual warns that batteries give off flammable hydrogen and oxygen gas while charging. Don't box them in with the inverter.
- Use the right cables and a fuse. A 1000 W load on 12 V draws close to 100 A on the battery side, so ask the seller for the recommended cable size and fuse.
- Switch-over time: One Inverter lists a switching time under 8 ms for its HI UPS inverters. That won't bother a fridge or fan, but a desktop PC may still reboot, so keep a small computer UPS for it.
FAQ
Ano ang pinagkaiba ng pure sine wave at modified sine wave? Pure sine wave is smooth like grid power. Modified sine wave is blocky, and Samlex says it makes motors run hotter. For a fridge or fans, choose pure sine wave.
How long will a 100Ah battery last with a 1000W inverter? It depends on the load. Using 50% of a 12V 100Ah lead-acid battery, our estimate is about 5 hours for a fan, two LED bulbs and Wi-Fi, or about 2.5 hours with a fridge and a second fan.
Can an inverter and battery run my aircon? Not with a setup this size. By Samlex's 5× rule a 1 HP inverter aircon needs a 4,000 W-plus inverter, and it would empty 1.2 kWh in under 1.5 hours.
Do I need solar panels for this? No. An inverter with an AC charger refills the battery from the grid. If you may add panels later, buy an off-grid hybrid with a built-in MPPT.
Can I connect it to my house wiring myself? Plug appliances into the inverter directly. Any link to your house circuits should be a changeover switch fitted by a licensed electrician.
Solar Leyte is run by MACC Systems & Energy Solutions Inc., a solar installer in Naval, Biliran.
Get a free backup power quote from MACC
Send a photo of your last BILECO or LEYECO bill and a list of what you want running in a brownout. MACC will reply with options and a written quote. No obligation.
- Call/Text: 0955 723 5093
- Email: official@macc-inc.com or benjie@macc-inc.com
- Website: www.macc-inc.com
- Request a quote online: solarleyte.com/quote
- Office: Brgy. Talustusan, Naval, Biliran 6543
Sources (all checked 25 October 2026)
- Anak Araw, Zamdon Solar Inverter 12V 1000W toroidal (₱6,000; 15 A AC charging, 145–275 V input, AVR, 3× surge)
- Beyond Power, listings: One Solar 12V 1000W wall type (₱6,200), One Solar 24V 1000W wall type (₱6,200), One Solar 12V 1200W hybrid with 40A MPPT (₱10,100), Solar Home 12V 100Ah (₱7,800), Solar Home 12V 200Ah (₱14,600), Higee 12.8V 120Ah LiFePO4 (₱13,400), Higee 25.6V 120Ah LiFePO4 (₱33,600)
- LakaSolar Philippines, One Solar 12V 1000W toroidal inverter (₱6,000) and Solar Homes 12V 100Ah gel battery (₱6,500)
- Panther, PSI 1000 pure sine wave (₱19,500) and PPI 2000 modified sine wave (₱24,500)
- One Inverter, HI series low-frequency pure sine wave UPS inverter (efficiency over 87%, switching time under 8 ms, AC charger)
- Samlex America, Advantages of pure sine wave over modified sine wave inverters (PDF)
- Samlex, SWI series manual (PDF) (inverter sizing factors, idle current, battery gas warning)
- Victron Energy, GEL and AGM batteries datasheet (PDF) and 12.8V LiFePO4 Smart datasheet (PDF)
- ICSC, PRESYO-PH: BILECO's September 2026 residential rate, ₱18.93 per kWh (latest month available on 25 October 2026)
- GMA News, Rotating brownouts may hit Visayas consumers on Aug. 26
- Appliance loads, the BILECO 8 August outage and the aircon rating: Solar Leyte, Solar Battery Price Philippines (2026)
- 1 kWh power station prices: Solar Leyte, EcoFlow solar generator prices