Guides · Faisalabad, Lahore, Punjab
Solar Backup for Medical Equipment at Home
Short answer
A hybrid solar system with a lithium battery can keep an oxygen concentrator, a CPAP machine or a fridge holding insulin running through load-shedding, if three things are right: the device is on a backed-up circuit, the battery is sized for the device's watts multiplied by the longest outage you need to cover, and the short switchover gap when the grid fails is handled, usually with a small online UPS in front of the device. Always follow the device maker's power guidance, and keep a fallback your doctor has approved, such as an oxygen cylinder or a cool box, for the times any power system fails.
This is an electrical guide, not medical advice. Your doctor and the equipment supplier decide what the patient needs; our job is to design power that supports it.
Start with the device, not the solar system
Before any sizing, collect three facts from each device's rating label and manual:
- Rated power in watts (W), or volts and amps (multiply them for an approximate watt figure).
- Start-up behaviour. Devices with compressors, such as concentrators and fridges, draw a short surge when they start.
- The maker's power guidance. Some manuals say whether the device may run from an inverter, a UPS or a generator, and what to do in a power cut. Follow it.
The wattages used below are round examples only.
Common home medical loads
| Device | What matters for backup |
|---|---|
| Oxygen concentrator | Runs continuously for hours; compressor surge at start; some models alarm when power drops |
| CPAP or BiPAP machine | Low power, but runs all night; a heated humidifier adds noticeably to the load |
| Fridge holding insulin or other medicines | Cycles on and off; keeps cold for a while if the door stays shut |
| Nebuliser, suction machine | Used in short sessions, often when needed most |
| Medical bed or air mattress pump | Small continuous load; mattress pumps must not stop for long |
Medical equipment backup at home
Critical
Oxygen concentrator, CPAP, fridge for medicines
Backup
Battery on a dedicated circuit
Clean power: pure sine wave
Modern hybrid inverters produce a pure sine wave output, the same shape as good grid power, which is what motors, compressors and electronic controls expect. Older or low-cost square or modified sine wave units can make motors run hot and noisy and confuse electronics. See pure sine wave inverters. All the hybrid inverters we fit have pure sine wave output.
The switchover gap
When the grid fails, a hybrid inverter needs a fraction of a second to switch your backed-up circuits to battery. Datasheets commonly state about 10 milliseconds in UPS mode and about 20 milliseconds in appliance mode. Fans and lights do not notice. A medical device may: some concentrators stop and restart, some sound an alarm, and a CPAP may reset its settings. Our guide to hybrid inverter transfer time explains the detail.
The safe approach for critical devices:
- Put a small online UPS in front of the device. An online UPS supplies the load continuously, with no gap, and the solar system keeps the UPS charged through long outages.
- Set the inverter to its faster switching mode where the model offers one.
- Test it. At handover, switch off the grid supply with the device running and watch what it does.
Size the battery for the longest outage you need to cover
The method is the same as any battery sizing (full guide): watts × hours, plus a margin.
Example arithmetic only, with round illustrative numbers. Suppose the label of a concentrator reads 400 W and the family wants it covered for 8 hours overnight, plus a medicine fridge averaging 100 W over the same period:
- Concentrator: 400 W × 8 h = 3,200 Wh
- Fridge: 100 W × 8 h = 800 Wh
- Total: 4,000 Wh, or 4 kWh
- Add about 20% for losses in the UPS and inverter and for battery reserve: about 4.8 kWh
That is for the medical loads alone. If the same battery also runs lights, fans and an AC through the night, add those loads, or the ACs will drain the battery before morning. Our guide to batteries for a full night of backup shows how whole-house loads add up.
Protect a reserve for the patient
Most hybrid inverters let you set the level at which the battery stops discharging, or switches back to the grid. For a home with medical equipment:
- Keep a reserve so the battery is never empty when load-shedding starts. If the inverter runs the house from battery every evening (SBU priority), the battery may already be low when the grid goes off. See SBU, SUB and utility-first modes.
- Charge from the grid if needed before a forecast outage on a cloudy day.
- Turn on app alerts for low battery and grid failure, so a family member knows. See solar monitoring apps.
Wire the medical circuit properly
- A dedicated, labelled socket on the backed-up side, near the patient, not shared with an iron, heater or AC.
- A backup loads panel if the house has many circuits, so the inverter only carries what matters in an outage. See backup loads panel.
- No extension leads running across the floor for a device that runs all night.
- A proper earth on the circuit, tested at commissioning.
Long outages, cloudy days and the fallback
A battery covers hours, not days. Two or three overcast winter days with long outages can empty any home battery that solar cannot refill. Plan for it:
- A generator can feed the hybrid inverter in a long outage. See using a home generator with a hybrid inverter.
- A non-electric fallback agreed with the doctor: an oxygen cylinder with a regulator, kept full and checked; a cool box and ice packs for insulin, following your pharmacist's advice on safe temperatures.
- A written plan on the wall: who to call, where the fallback is kept, and how to switch to it.
Oxygen and fire safety
Oxygen makes fires start more easily and burn faster. Keep the concentrator and any cylinder well away from the inverter, battery and any heater, follow the device maker's clearance advice, and never allow smoking or open flames nearby. The inverter and battery need their own shaded, ventilated, dry spot; see where to install your inverter and battery and fire safety for solar and lithium batteries.
Is a full solar system needed?
Not always. If the patient's equipment is the only concern and outages are short, a correctly sized UPS with a pure sine output may be enough; our UPS vs solar guide compares the options. A hybrid solar system makes sense when the household also wants lower bills, longer backup and daytime power from its own panels. Our projects start at about 6 kW, which suits most family homes with ACs.
| Option | What it covers | Price |
|---|---|---|
| Hybrid solar system with lithium battery, sized with medical loads | Whole-house solar, medical circuit backup, long outages | WhatsApp for today's rate |
| Additional lithium battery capacity for medical reserve (per kWh) | Longer backup for the medical circuit | WhatsApp for today's rate |
See the solar system price guide and lithium battery prices.
Checklist for families
| Check | Done? |
|---|---|
| Device rating label and manual read; maker's power guidance noted | |
| Medical socket on the backed-up circuit, labelled | |
| Online UPS fitted where the device cannot tolerate a switchover gap | |
| Battery sized for medical loads × longest outage, plus margin | |
| Battery reserve set; low-battery alerts on a family phone | |
| Switchover tested with the device running | |
| Doctor-approved fallback in place and checked |
Hospitals and clinics need a different level of design; see solar for hospitals and clinics.
How Solar Works Pakistan designs for medical loads
We start from your device list and the outages you face, then design the inverter, battery, backed-up circuits and settings around them. Our engineers set the battery reserve and switching mode, test switchover at handover with the device running, and show the family how the system and app behave in a power cut. We do not certify or advise on medical equipment itself.
Panels, inverters and batteries carry the manufacturer's warranty per product. Our service warranty covers the first year under applicable project terms, and after a complaint is registered we target sending service personnel within 48 hours to begin diagnosis. That is a target for a visit, not a promise of a fix, which is one more reason to keep a fallback.
Solar Works Pakistan was founded in 2021 and has served 300+ customers, including 50+ industrial clients.
Get today's price or a free site survey
Send us photos of each device's rating label, your last 12 months of bills and your usual load-shedding hours.
- WhatsApp or call: 0336 666 4321
- Email: info@solarworks.pk
- Head office: Main Boulevard, Sargodha Rd, Block F FDA City, Faisalabad (Faisalabad page)
- Lahore branch: 2nd Floor, Jeff Heights, Gulberg, Lahore (Lahore page)
- Hours: 9:00 AM to 6:00 PM, daily
We serve all of Punjab, and site surveys are normally free. You can also contact us online.
Frequently asked questions
Can an oxygen concentrator run on a solar inverter?
Often yes, from a pure sine wave hybrid inverter with enough battery, on a dedicated backed-up circuit. Check the maker's power guidance, and use an online UPS in front of it if it cannot tolerate the switchover gap.
How big a battery do I need for an oxygen concentrator overnight?
Multiply the concentrator's rated watts by the hours you need, add other loads on the same battery, then add about 20% margin. For example, a 400 W device for 8 hours needs 3.2 kWh before margin. Use your own device's rating.
Will a CPAP machine restart when the inverter switches over?
It may, depending on the machine and the inverter's transfer time. A small online UPS in front of the CPAP removes the gap.
How do I keep insulin cold during load-shedding?
Keep the fridge on the backed-up circuit, avoid opening the door, and keep a thermometer inside. Have a cool box plan agreed with your pharmacist for long outages.
Is solar backup enough on its own for life-support equipment?
No power system should be the only plan. Keep a doctor-approved non-electric fallback, such as an oxygen cylinder, and a written plan for using it.
Do you install systems just for medical equipment?
Our projects start at about 6 kW, so we design whole-house hybrid systems with the medical circuit as a priority. If you only need a small backup, a UPS may be the simpler choice.