Note: The information provided below is only intended as a guide. Additionally, you need to consult a qualified Solar System installer.
If you have several hours of sunshine each day and the electricity tariffs where you live are high then perhaps powering the AC using solar is an option you should consider, right?
After all, you’ll be using the freely available sunshine and that could mean some cost savings for you.
Well, it’s not that straightforward, unfortunately. There are a number of considerations – for example, how big a system is and the associated cost you need to invest in the system to keep the AC running compared to the cost of running it on the grid (if available).
So, read on to find out how many solar panels you need to run a 6000 BTU AC on solar, what size of system you’re likely to need, and also whether it is worth it!
Quick answer. You can use about 10 pcs of 320 watt solar panels or 15 pcs of 200 watt solar panels to run the AC continuously assuming your location receives on average about 5 hours of sunshine.
In addition to the solar panels, you need a charge controller, inverter, and a battery bank for an off-grid solar system.
Read on to find out the capacities of the inverter, charge controller, and battery bank you can use and whether it is worthwhile running the AC on solar.
How to Calculate the No. of Solar panels to Run a 6000 BTU Air conditioner (AC)
With 320 watt solar panels, you’ll need about 10 pcs from: number of solar panels = power consumption of the AC x number of hours of operation/ (solar panel power rating x number of hours of sunshine).
500 watts x 24 hours/ (5 hours x 320 watt solar panel) = 10 solar panels
If you are using 200 watt solar panels, you’ll need a larger area for the 15 panels.
This is from the calculation, number of solar panels = power consumption of the AC x number of hours of operation/ (solar panel power rating x number of hours of sunshine), i.e. (500 x 24)/(200 x 5) = 15 panels.
How many solar panels you need to run the ac depends on how long you’re going to run it and the power rating of solar panels.
What Size of Battery to use for a 6000 BTU/hr AC?
You can use a battery bank of about 250 Ah, at 48 V to power the AC, assuming it consumes about 500 watts of power and runs for 24 hours.
The battery bank will be smaller if you run the AC for a period considerably shorter than 24 hours!
Considering the size and likely cost of the battery bank, it will likely not be economical to power the AC on batteries for 24 hours especially if the grid is available.
What Size of Inverter you need?
As a guide, you should consider a 1,500 watt + pure sine wave inverter to power the AC.
If you plan to connect other electrical accessories use an inverter with a larger capacity (watts).
What Size of Charge controller?
An 80 amp MPPT charge controller should be able to work provided the solar panels are wired such that the combined current draw does not exceed 80 amps.
The Advantages of using Solar
While you could argue that you are using the freely available sun to power the AC, the high initial cost and long payback period water down the benefit of using freely available energy.
Disadvantages of using solar
#1. High Initial Cost
There is a significant initial investment cost when you decide to solar, especially if the solar system is designed to power the AC for 24 hours a day.
Keep in mind that you need to plan to replace the batteries about every 3-5 years depending on the quality of batteries used.
#2. A large battery bank takes up space and adds to the overall weight
Additionally, the batteries required to power the solar system can take up significant space and add up in weight.
This can be an issue if you’re in a limited space like an RV.
How you Can Lower the Initial costs associated with using Solar
#1. Run the AC for a few hours
Consider running the AC for a few hours each day as opposed to throughout the night. This lowers the size of the battery bank needed and the associated investment cost.
#2. Use a Solar grid-tie solution instead
You can also use a grid-tie inverter solution that does away with batteries and makes the solar system cheaper.
However, to use such a system, the grid must be available.
#3. Reduce AC’s power consumption by insulating the room
Consider insulating the area that the ac is cooling to reduce the amount of energy expended by the AC.
Alternatives to Using Solar to power a 6000 BTU AC
You can use a genset instead. The initial investment cost with a genset is considerably lower than when you use solar but requires periodic maintenance in addition to adding gas to keep it running.
Is it worth it? Should you use it?
If your interest is to save money, then it is not worth it in my opinion, as it can take you about 10 years just to recoup the initial investment cost, assuming the AC is running 24 hours a day.
How much it costs to run a 6000 BTU/hr ac per day?
Assuming a tariff of 12 cents per kWh, at an estimated daily consumption rate of 12 kWh (AC is assumed to run for 24 hours a day), it costs you USD 1.44 to run the AC a day.
The annual cost of running the AC on the grid is 365 x USD 1.44= USD 525.
Assuming the estimated off-grid solar system at the current prices is USD 5,000 (without batteries), the payback period is 9.5 hours.
Solar system Components to Run a 6000 BTU AC
Offgrid solar system
The actual configuration to use depends on mainly how many hours of sunshine your location receives on average and how many hours the system will run in a day.
This is just one example of several configurations you can use assuming you plan to power the ac off-grid for 24 hours.
To power a 6000 BTU AC, you can use
10 pcs of 320 watt solar panels,
- an 80 amp MPPT charge controller,
- a 1500 watt pure sine wave solar system and
- a 250Ah battery bank at 48V to run the ac for 24 hours. If it runs for a few hours then the battery bank will be smaller.
Grid-tie Solar System
You can also use a grid-tie solar system.
This has the advantage of relying on the grid and saving you the investment in batteries however only works with the grid.
An example of a setup you can use includes:
- 10 pcs of 320 watt solar panels and
- 3000 watt solar inverter and
- solar power optimisers that ensure that reliable power flow from the solar panels to the inverter regardless of shading of the panels.
However, this would only use solar power during the day and rely on the grid at night.
How much Power (watts) does a 6000 BTU Air Conditioner (AC) Use?
A 6000 BTU/hr ac has an estimated continuous power draw of about 500 watts at 115V. At startup, the power draw can be momentarily as high as 3-5 times the continuous power draw.
You need about 10 pcs of 320 watt solar panels or 15pcs of 200 watt solar panels to run the AC continuously assuming your location receives on average about 5 hours of sunshine.
In addition, you can use an 80 amp MPPT charge controller, a 250Ah battery bank at 48V DC, and 1,500 watt pure sine-wave inverter for your offgrid solar system.