# How many solar panels do I need to power a refrigerator?

02/28/2022

Some buy the solar panels to charge their car, others choose to supply charge for their home. Anyway, different people, different needs. Here in this post, I would like to introduce how many solar panels we need to charge a refrigerator. Of course, if you have any other questions, please leave the messages below.

The first thing you need to know is that an average domestic fridge uses 350kWh of electrical energy per year and would need 300 watts of solar panels to supply it. A 100 Ah reservoir would also be needed to supply the compressor motor surge current and to run the refrigerator at night when the solar panel is not generating power.

## How to calculate the size of the solar panel for a refrigerator

Home refrigerator compressors consume energy in cycles, as the motor stops and starts according to temperature fluctuations inside.

To size the solar panel, it is best to use the average power used over a period of time, but sometimes the current draw will be low and other times high.

That's why I recommend supporting properly sized solar panels with a deep cycle battery and inverter. The battery acts as an energy reserve to supply high starting currents of the compressor.

How much energy does a fridge use?

The instantaneous power consumption of any refrigerator is misleading, because the compressor motor only runs about 50% of the time.

Newer model compressors tend to run longer, but are much more efficient and don't use as much power overall. I did a current draw test on an old refrigerator versus a new refrigerator in this post.

I discovered that a 10-year-old refrigerator used twice as much energy as a new one. This is important because it increases the amount of solar battery support needed to run an old refrigerator.

A solar battery is needed as the compressor motors cycle on and off and consume 3 times more power at start up. At other times, it won't work at all and will draw zero amps.

The solar battery acts as a reservoir to supply the energy peaks associated with the compressor cycle. Due to these stops and starts, it is difficult to assess how much energy a refrigerator consumes at any one time.

Another great option is to assess energy consumption using the manufacturer's estimate from the appliance label. Most refrigerators consume between 200 and 900 kWh/year.

## What size solar panel is needed for a fridge?

If the average energy consumption of the refrigerator is 350kWh per year, we will need:

350kWh / 146kWh = 2.4 solar panels of 100 watts each.

The solar inverter will have losses and it is always better to overestimate solar power sources, so I would use 3 x 100 watt panels, with a 500 watt inverter and a 100 Ah deep cycle battery.

### Can a 100 watt solar panel run a refrigerator?

A 100-watt solar panel could power a fridge for a limited time and would need solar batteries for energy storage. A 100-watt solar panel produces about 400 watt-hours of energy per day, assuming 4 hours of peak sun irradiation. Yes, the irradiance depends on the location. Therefore, different places may receive different sunlight and energy.

### What size battery to run the refrigerator?

This question is easy for anyone to know. The needs of the solar battery are not that high. The average refrigerator needs 40 watts of power every hour, which is equivalent to 960 watt-hours of battery capacity for 24 hours to run a refrigerator. 960 watt-hours equates to a battery capacity of 80 Ah, so a 160 Ah deep-cycle lead-acid battery with a DoD of 50% would be needed. Anyway, any questions, please leave us a message.