Brownout preparedness guide
Brownouts in Batangas and across the Philippines can last minutes or a whole day. A battery system makes them much easier to live with, if it is sized for what you actually need to run. This guide walks you through that in four steps. You do not need to be an electrician.
- List the essential loads.
- Work out watts (power) and watt-hours (energy).
- Choose between portable and home storage.
- Use it safely.
When you're done, enter your list in the backup calculator, or start from Which MARSTEK product is right?.
Step 1: Decide what is truly essential
Group your appliances into three groups:
| Group | Typical examples | Plan |
|---|---|---|
| Must run | Lights, electric fans, Wi-Fi router, phone charging, medical devices | Always include |
| Nice to have | TV, laptop, rice cooker for one meal | Include if the budget allows |
| Skip during brownouts | Aircon, electric water heater, flat iron, oven | Usually too big for portable units. Needs a properly sized, professionally installed home system |
If anyone in the household depends on powered medical equipment (for example, a nebulizer or oxygen concentrator), size for it first. Check the requirements with the equipment supplier as well.
Step 2: Estimate watts and watt-hours
You need two numbers, because a battery system has two separate limits:
- Power (W): how much can run at the same time. Add up the watts of everything that will be on at once. This total must be below the product's continuous output rating.
- Energy (Wh): how long it can keep running. For each appliance, watts × hours of use = watt-hours. Add them up. This total must be below the battery's usable energy.
Where to find the watts: look at the nameplate or sticker on the appliance (for example, "220V 60Hz 45W"). If it shows only amps, then watts ≈ volts × amps. For example, 220 V × 0.5 A ≈ 110 W.
Appliances with motors or compressors (refrigerators, freezers, water pumps, aircon) can draw several times their running power for a moment when they start. That is why products list a peak rating as well as a continuous one. Check that the peak rating covers the start-up of your largest motor load.
Worked example (illustrative only)
The appliance wattages below are typical example values, not measurements and not MARSTEK data. Use the nameplate figures of your appliances. The usable-energy factor matches the calculator's default assumptions (90% usable × 90% efficiency = 81%). It is an assumption for planning, not a manufacturer specification for every product.
An 8-hour evening brownout for a small household:
| Appliance | Qty | Watts each | Running W | Hours | Energy (Wh) |
|---|---|---|---|---|---|
| LED bulb | 3 | 10 | 30 | 8 | 240 |
| Electric fan | 2 | 50 | 100 | 8 | 800 |
| Wi-Fi router | 1 | 10 | 10 | 8 | 80 |
| Phone charging | 2 | 10 | 20 | 2 | 40 |
| TV | 1 | 100 | 100 | 3 | 300 |
| Total | 260 W | 1,460 Wh |
1. Power check: 260 W running if everything is on at once.
2. Energy check: 1,460 Wh ≈ 1.46 kWh.
3. Compare with products. Usable energy ≈ nameplate capacity × 0.81 (assumed):
| Product | Continuous output (manual/datasheet) | Capacity (manual/datasheet) | ≈ Usable at 81% (assumed) | Covers 260 W? | Covers 1,460 Wh? |
|---|---|---|---|---|---|
| M1200 | 1,800 W | 1,030 Wh | ≈ 834 Wh | Yes | No, only about 57% of the 1,460 Wh needed |
| V500 | 500 W | 2,009.6 Wh | ≈ 1,628 Wh | Yes | Yes |
| M2200 | 2,400 W | 2,240 Wh | ≈ 1,814 Wh | Yes | Yes |
| VENUS E 3.0 | 2.5 kVA backup (datasheet) | 5.12 kWh | ≈ 4,147 Wh | Yes | Yes, with room to spare |
4. Add a refrigerator? Suppose the fridge label says 1.0 kWh per day (illustrative). Over 8 hours that is about 1,000 × 8 ÷ 24 ≈ 333 Wh, so the total becomes ≈ 1,793 Wh. The V500 (≈ 1,628 Wh) would now fall short, the M2200 (≈ 1,814 Wh) would only just cover it, and the VENUS E 3.0 covers it comfortably. Also check the fridge's start-up surge against each product's peak rating: V500 1,000 W, M1200 3,600 W, M2200 4,800 W (manuals).
Brownouts usually end, and solar panels can recharge during the day. The V500, M1200 and M2200 all take solar input. Recharging is not included in the example, so a real plan may need less battery, or may cover longer outages, than these numbers show.
Step 3: Portable or home storage?
| Portable power station (V500, M1200, M2200) | Home energy storage (VENUS E 3.0, MARS I PLUS, V6000) | |
|---|---|---|
| Installation | None. Plug appliances into the unit | Installed into the home's wiring. MARS I PLUS and V6000 require qualified/professional installers per their manuals |
| How backup works | You move plugs from the wall to the power station | Backup/EPS outputs or circuits supply selected loads during an outage (product-specific) |
| Best for | Lights, fans, Wi-Fi, TV, laptops, a fridge (size carefully), camping and events | Several rooms or circuits, daily solar self-consumption, larger or longer outages |
| Moves with you | Yes | No |
| Solar | Plug-in panels (MC4 or XT60, product-specific) | Rooftop PV (existing or new, product-specific) |
Rules of thumb:
- Renting, or only need a few essentials: a portable station. The V500 has an IP65 rating and is fanless. The M-series offers higher output and more ports.
- Already have rooftop solar: look at the VENUS E 3.0 (AC-coupled).
- Installing solar for the first time and want backup: look at the MARS I PLUS (hybrid inverter with EPS backup loads).
- Weak or no grid, or whole-property backup: look at the V6000 (6 kW inverter, ≈15 kWh, off-grid capable).
See Which MARSTEK product is right? for the full decision guide. For a home system, Silvera Solar Power needs to do a site survey before quoting.
Step 4: Safety basics
- Read the manual for your specific product. Its limits and warnings override any general advice here.
- Never exceed the continuous output rating. Overloading trips protection and can cause overheating.
- Do not connect a portable power station into your house wiring, for example by back-feeding through an outlet. Plug appliances directly into the unit. Wiring a battery system into a home must be done by a qualified installer, following the manual and local electrical codes.
- Keep ventilation clear. Do not cover vents or fans, and do not charge in enclosed, hot spaces.
- Keep units dry, unless the product is specifically rated for wet conditions (for example, the V500 is IP65). Even then, close the port covers.
- Keep away from heat and flames. Do not leave units in a hot car or in direct sun for long periods.
- Use proper extension cords rated for the load, and do not daisy-chain power strips.
- Keep children away from units and cables.
- Damaged, swollen, smelling or leaking? Stop using it, move it away from anything flammable, and contact Silvera Solar Power.
Before brownout season: a checklist
- Charge the battery fully. For storage between brownouts, follow your manual's storage charge level and top-up interval (for example, the V500 manual says 50–60% and recharge every 1–2 months; the M1200/M2200 manuals say 60–80% and top up every 3 months).
- Test-run your essential loads on battery for 15–30 minutes.
- Keep the manual, the AC charging cable and any solar cables together with the unit.
- Install the MARSTEK app and check that the unit connects.
- Write down your essential-load list and wattages, and save it in the backup calculator.
Related
Sources
Product figures on this page come from these documents. All appliance figures are illustrative.
- V500 manual (Drive): 500 W / 1,000 W peak, 2,009.6 Wh, storage rules
- M1200 manual (Drive) · M2200 manual (Drive): AC ratings, capacity, storage rules
- VENUS E 3.0 datasheet (Drive): 5.12 kWh, 2.5 kVA backup
- MARS I PLUS manual (Drive) · V6000 manual (Drive): professional installation requirement