If your home or business has a 5-ton air conditioner, you may be wondering how many solar panels you’ll need to run it?
A 5-ton air conditioner, on average, will require 6 kW/hour, which can be produced by a 10 to 12 kW solar array composed of 30-40 x 300-watt solar panels, assuming the AC unit is used for 10 hours per day.
How much power does a 5-ton AC use?
A 5-ton air conditioner produces an impressive 60,000 BTU of cooling power. This is sufficient to cool homes of up to 3000 square feet. Such a big central air conditioner will use a substantial amount of power, and the wattage of a 5 ton AC can range from 4,000 to 8,000 watts. This equates to 16 to 34 amps (240V circuit).
The most important factor is to determine the air conditioner’s overall wattage. All the information that you will need can be found on the specification sheet:
- Look for the power specified in the specification sheet (measured in Watts).
- Look for the EER rating on the specification sheet. Wattage can be calculated by dividing BTUs by the EER rating, for example, 60,000 BTU / 10 EER= 6,000W.
- Look for the current in the specification sheet (Amps) and voltage (V). Wattage is calculated by multiplying current by voltage; for example, 25 Amps* 240V= 6,000W.
A typical 5-ton air conditioner (with a 10 EER rating) uses 6,000 W to operate.
If you run the air conditioner for 10 hours a day, it will use 60 000 W (10 x 6 000 W). If you use the air-conditioner for only 5 hours per day, this number will decrease to 30 000 W.
You will use this number to calculate the number of solar panels you will need to run the 5 ton AC unit.
How many solar panels will I need?
Grid-tied Solar Panels
With a grid-tied system, you do not need batteries for the installation. The power generated by the solar panels is fed directly to an inverter connected to the utility power. The inverter can switch seamlessly between solar and utility power as needed.
As we have calculated before, running the 5 ton AC for 10 hours per day will use 60 kW of power. We need our solar panels to produce an average of 6 kW/Hour over the duration of the 10 hours.
20 x 300 W solar panels will produce 6000 W (6kW), but this will only be during the peak midday sun in the summer. We will thus need more solar panels to reach an average of 6 kW.
A 300 W solar panel will only produce an average of 150 – 200 W of power during the whole day. Taking that into account, we will need 30 – 40 x 300 W solar panels to produce the required average of 6 kW / hour of power.
Key Takeaways
- Determine the amount of hours you want to run the AC to calculate the power usage – 10 hours x 6 kW = 60 kW
- Solar panels will not produce peak power during the whole day and taking that into account you will need 30 – 40 x 300 W solar panels to produce the required 6 kW/hour to power the 5 ton AC.
Off-Grid Solar Panels
An off-grid solar panel system is, as the name implies, not connected to the power grid. To run a 5 ton AC unit from an off-grid system, you will need a battery bank to do it.
Solar panels can’t actually be used to “run” an air conditioner. Because AC units demand consistent power, and solar panels only give intermittent electricity, the unit would constantly shut off and on as the power from the panels fluctuated above and below what was needed to run the AC.
As the AC unit will use 6kW/hour, you will need 6kW of battery capacity for every hour you wish to run the AC. – 10 hours will need 60 kW of battery capacity, which is a fairly substantial battery bank.
The calculation for the number of solar panels that you will need will be the same as that used for the grid-tied system – 30 – 40 x 300 W solar panels. This only difference will be that the solar panels will power the AC unit and charge the battery bank.
