Entirely on what you're running, which is why the calculator shows two numbers. On essentials alone — lights, internet, fridge, cameras, water pump — two battery modules carry most houses right through the night, and that covers almost every outage on this coast. Run two or three minisplits as well and the same bank lasts a quarter as long. Add modules until the second number looks right to you. The figures assume a steady average draw; the load audit gives you the real one.

Either, and it's your choice. Most houses here are split across two legs of the panel. One inverter backs up one leg — about half your circuits — and you decide which half: lights, internet, fridge, water pump, cameras, the sockets that matter. For most people that covers everything they actually miss during an outage, and it is where nearly all our clients start. Add a second inverter and the other leg is covered too, which is genuinely the whole house. Because both inverters share the same battery bank, the second leg costs much less than doubling the system.

Briefly, and we would rather tell you now than have you discover it. The grid passes straight through the system untouched; when it fails, the batteries take over in under 20 milliseconds — barely one cycle of the AC wave, or under 30 if your house uses two units in parallel. Lights may blink once. Air conditioning, fridges, pumps, routers, TVs and gate motors carry on without restarting. A desktop computer without its own little UPS may reboot, so if you work from home we'll suggest a small one for the desk. Compare that to a generator: 10 to 30 seconds of full darkness, every time.

Nothing dramatic — and that is deliberate. Grid power runs through the unit on a normally-closed path, so if the inverter ever fails, or we switch it off for service, CFE carries straight through to the house exactly as it did before we arrived. You lose the backup until we fix it. You never lose the house. It also means we can service or swap a unit without leaving you sitting in the dark waiting for us.

If you want redundancy beyond that, two smaller inverters — one per leg — mean a single failure only takes out half your backup while the other leg carries on. It is the reason some clients choose a pair of 3 kW units over one larger box. The battery bank is shared between them, so that redundancy covers the inverters, not the batteries.

Yes, and plenty of people choose to. Air conditioning is far and away the biggest load in a house on this coast, so carrying it is the difference between a few hours of runtime and a whole night on the same batteries. Leave the minisplits off the backup and they simply go quiet during an outage, while lights, internet, fridge, water pump, cameras, gate and ceiling fans carry on exactly as normal. It costs nothing either way — we decide it together at install, and it can be changed later if you add batteries.

We install LiFePO₄ (lithium iron phosphate) batteries, rated for 6,000+ cycles and typically 10 to 15 years of service in a home like yours. They are not the lithium chemistry that makes the news — LiFePO₄ is specifically chosen for thermal stability, which matters in a climate like ours. Capacity fades gradually rather than failing outright, and individual modules can be replaced without touching the rest. Both lines carry a 5-year warranty as standard, with 10 years available on the AXE.

Quiet rather than silent, and it's worth being precise. At rest and on light load you will not hear it. The only moving part is a cooling fan, and under heavy load it becomes audible — Growatt rates the unit at up to 75 dB flat out, which is a real number and we would rather quote it than pretend. In practice that only happens when the house is pulling hard, and it is mounted indoors: bodega, garage, service patio or utility room, not in the garden. A generator, by contrast, sits outside at 60–75 dB continuously, all night, whether you are using 200 watts or five kilowatts. It needs roughly a metre and a half of wall, ventilation, and to stay out of direct sea air.

Yes. Every system uses a Growatt hybrid inverter, so panels can be added afterwards without replacing anything. If you already have solar, we can usually integrate the existing array; bring us the inverter model and we'll tell you straight away whether it plays nicely.

A little, and here is the honest arithmetic. The equipment draws standby power around the clock — up to about 75 watts on the larger units, roughly 50 kWh a month — a couple of hundred pesos on a basic tariff, and noticeably more if you are on DAC. Recharging after an outage adds very little on top, because you are only replacing what the outage drained. Solar changes the picture entirely: panels cover the standby draw and then some, which is why most clients who start with backup end up adding them. Every system we install is built ready for that.

This is what the system is for. It rides through the outage automatically, and if you're not on the peninsula you can check the state of the house from your phone. For multi-day outages, a solar-paired system recharges each day and can run indefinitely. We also do pre-season checks each May — worth booking early, because June and July are our busiest months for exactly this reason.

Yes, and this is the part most people underestimate. The system conditions incoming power continuously, so the sags, spikes and brownouts that quietly destroy A/C compressors and appliance boards never reach your equipment. Many clients see the value here long before they see a full blackout.

Equipment carries the manufacturer's warranty — typically 5 years on the inverter and 10 on the batteries — and our installation work is warranted separately. Support is local: you call or message +52 984 212 9876 and reach the people who installed your system, not a call centre in another country.

Regularly — a good share of our work is for owners who are abroad. We coordinate with your property manager, builder or architect, send photo updates through the install, and commission the system on a video call so you see it tested yourself.