How Many Solar Panels to Run an Air Conditioner?

More and more homeowners are wondering if they can use solar panels to power their AC and how much they need to run their air conditioners. The number of solar panels required to run an air conditioner depends on several factors, namely the size of the air conditioner unit and the wattage of the solar panels.

Generally speaking, 1200 watts of solar panels are required per ton of cooling power, which is actually equivalent to 20 x 300 watts of solar panels to run a 5-ton air conditioner. Let’s discuss in depth： how many solar panels to run the air conditioner.

Can Solar Run Air Conditioners?

Yes, you can power an air conditioner with a solar system. A typical air conditioner needs at least 1.2kw to 2.5kw to work. The solar system can provide up to 2kw or 4kw of electricity, therefore, it can be used to run the air conditioner. However, this can come at a cost.

When you use a solar panel to run your AC power, it uses almost all of its energy, which means you’ll have less energy to power other appliances in your home. An important part of using a solar panel to power AC is to know the capacity of the panel and compare it to the energy requirements of the AC before using it.

Read More: Can Solar Panels Charge An Electric Car?

Can A Low-Watt Solar Panel Run An Air Conditioner?

No, a low-watt solar panel cannot be an air conditioner. A low-watt solar panel can be as low as 100 watts, which means it can never power an air conditioner. The smallest air conditioner requires about 500 watts of power to run.

What Determines Power Consumption Of AC? 

There are many factors that affect AC power usage, from the weather to the location and type of buildings.

• Weather

The first thing to consider when determining the power consumption of an air conditioner is the weather. Obviously, if it’s hot, you’ll be using the air conditioner more and need more electricity to run.

Also, air conditioners work by cooling the air. So, for example, if the ambient temperature is 105 degrees Fahrenheit, the air conditioner needs to work harder to cool it down to the set temperature than if it were only 80 degrees Fahrenheit.

• Place

The climate you live in directly affects how much you use your air conditioner and how much energy your air conditioner uses. So if you live in Texas, you’re going to need more solar panels to run your air conditioner than someone who lives in Minnesota.

Likewise, if your home has a lot of shade, it will be more efficient at cooling than a sunny home.

• Building Type

Energy-efficient building design can play a big role here. For example, taller, more compact buildings are more effective at cooling than low, cluttered buildings.

Rooflines can protect your home from the hot summer sun and also help keep you cool, reducing the need for air conditioning. Likewise, insulation and double-glazed windows will allow your house to cool more efficiently, reducing the amount of energy used by your air conditioning system. There are many factors that affect AC power usage, from the weather to the location and type of buildings.

How Many Solar Panels To Run Air Conditioner?

This is a bit of a complication because not all solar panels are the same. Solar panels used in private homes are typically between 100 and 250 watts. A 250-watt solar panel provides more energy than a 100-watt solar panel, so you’ll need more of the latter to run the same air conditioner.

You also need to consider the size of your air conditioner and the amount of time you run the air conditioner each day.

In the example of a five-ton air conditioner, let’s say you run the air conditioner four hours a day when the temperature is at its peak.

If the five-ton alternator were running continuously during this period (which would be the maximum usage or “worst case” case) it would consume 24 kWh.

If you also have about four peak solar hours per day, which is the case in summer in most climates, then you can get about 300 watts per hour from a 300-watt solar panel, which equates to 1.2 kWh.

So you need 20 solar panels of 300 watts each to generate 24 kWh, enough for a 5-ton air conditioner.

Assuming irradiance of 4 peak hours of sunshine per day, the air conditioner requires 1200 watts of solar panels per ton of cooling capacity. A 100Ah battery per ton is recommended for the expected runtime per hour. This will allow operation when irradiance is low and provide a reservoir to supply motor inrush current.

How to Determine The Number Of Panels Needed For AC 

For most appliances, you can figure out how many solar panels you’ll need with a fairly simple calculation based on the wattage the device uses per hour. However, when it comes to communication systems, things get a little more complicated.

First, as the air conditioner cycles on and off, you need to average its energy usage to determine how much power it uses per hour.

Also, AC power is rated in tons not watts because different air conditioning units have different efficiencies. Therefore, the electrical power rating of a unit is not an accurate measure of its cooling power.

Instead, AC units are measured in tons. A ton of AC rating translates to the ability to melt 2,000 pounds of ice in 24 hours. Therefore, the more tons, the more air the unit can cool per hour.

Although less common, a ton is sometimes expressed as 12,000 BTU/h (British Thermal Units/hour) or 3.5 kW (kilowatts).

If you have four peak hours of sunshine a day, for every ton of cooling capacity in your air conditioner, you need 1,200 watts of solar panels. Most modern air conditioning units have a cooling capacity of between 2 and 5 tons.

Final Thoughts

In conclusion, using solar panels to power your air conditioning system can be a smart idea that can help you save money in the long run. While the up-front costs can be a bit large, with careful thought, you can develop a good solar plan that will allow you to power everyday household appliances (like air conditioners) for as little money as possible.

For a 5-ton air conditioner, you need 20 x 300-watt solar panels to run your air conditioner for 4 hours a day at maximum temperature.

To figure out how many solar panels you’ll need for your own air conditioner, you’ll need to consider the size of your air conditioner unit, the wattage of each solar panel, and other environmental factors such as the weather, house design, and location.

It’s also important to consider battery backup to ensure you can run the air conditioner when you need it, including at night.