- Yes, in daytime, if your inverter and panels are big enough.
- Heaters and geysers use 1,000 to 3,000W, so they need a 5kW or bigger inverter.
- Running them all night on a battery is usually not practical.
- Heat water in the afternoon using solar, then use it in the evening.
This winter, gas is being supplied to homes only at fixed times. Many families are buying electric heaters and geysers, and asking: can my solar system run them? The short answer is yes, during the day, if your system is sized for it.
How much power do heaters and geysers use?
| Appliance | Typical power |
|---|---|
| Small fan heater | 1,000 to 2,000W |
| Oil-filled heater | 1,500 to 2,500W |
| Electric storage geyser | 1,500 to 3,000W |
| Instant electric geyser | 3,000W and above |
These are heavy loads. One heater uses as much power as 20 to 40 ceiling fans.
What size system do you need?
- 3kW to 4kW inverter: fine for one small heater for short periods, but leaves little room for anything else.
- 6kW inverter: can run a heater or a geyser in daytime along with normal home loads.
- 8kW and above: for a heater and a geyser together, or for larger homes.
Can a battery run a heater all night?
Usually not. A 2,000W heater running for 5 hours needs about 10kWh, which is two full 5kWh batteries. That is expensive and leaves no backup for load shedding. Batteries are best kept for lights, fans, fridge and internet at night.
Smart ways to use solar heat in winter
- Heat water in the afternoon. Run a storage geyser between 11am and 3pm when solar is strongest, then use the hot water in the evening.
- Use a timer. A simple timer switch makes sure the geyser runs only in sun hours.
- Heat one room, not the whole house. A small heater in the room you use is far cheaper.
- Keep panels clean. Smog and dust cut winter output. Read our panel cleaning guide.
Frequently asked questions
Will a heater damage my inverter?
Not if the inverter is rated well above the heater’s power. Overloading causes the inverter to trip, so size it correctly.
Is a gas geyser or electric geyser better with solar?
With solar, an electric storage geyser used in daytime saves gas and money. Keep gas as a backup for cloudy days.
Does solar work on foggy winter days?
Output drops on heavy fog or smog days. On clear winter days solar works well, because panels perform better when cool.
Talk to our team
Our Lahore team can size the inverter and battery for you. It takes one message.