An AC unit is one device that consumes a lot of electric power. Americans spend over 29 billion dollars annually on electricity bills incurred from Air conditioner powering in the USA alone. Luckily, more powerful solar PV systems have been introduced into the market in recent years. It is not uncommon to find an institution or a home running their AC unit using solar energy.
But the big question is can you run an AC unit on solar panels alone? Is a solar battery backup necessary?
Well, the answer is Yes and No. If you have solar panels with ample wattage, then you can run an AC unit perfectly during the day. This is because the energy harnessed from the sun during the day can run an AC unit if the panels are powerful. The problem arises at night. Why, you ask? Keep reading this guide to find out.
Can solar panels run AC without batteries?
You should know that AC units require powerful solar panels and potent battery backup. A standard AC unit is 1Ton, and it needs between 1500-3000W per hour to run this type of AC. The different brands bring about variations in the wattage consumed. To check how much your AC unit consumes. Check the label.
As seen, AC units are high-power-consuming devices. For this reason, you will be forced to have mighty solar panels to run a single unit of AC. Due to power surges, you might be forced to have a solid, powerful solar battery backup of more than 600aH.
There are two types of solar panels used to power AC units. An and on the grid or grid-tied Ac unit. An off-the-grid unit only uses power generated by the sun to run. If you do not have a solar battery or solar energy is scarce, your device might not run.
An on-the-grid or grid-tied AC unit is connected to the company that produces the AC. If solar energy is scarce, you tap into the grid and consume the power from the manufacturer. This power is usually electricity.
Since our primary goal is to know if a solar panel can power an AC unit without a battery, the answer is yes. Off-the-grid AC units can run solely on solar panels, provided the panels are powerful.
For example, a 1.5 Ton AC unit will consume around 3KWh-10kWh. This depends on the type of AC unit. So if you have solar panels that produce that much power, you can run your AC unit. However, if solar energy is scarce, maybe during cloudy days or at night, you might have an issue.
Can solar panels run an AC during the night?
Solar panels can’t store the charge required to run an AC unit. A solar panel will power an AC unit during the day when there is a surplus of solar energy. But during the night, when there is no sunlight energy, the AC will shut down.
Since you cannot use a solar panel to run an AC unit during the night, you should invest in a powerful solar battery. A solar battery will store the excess energy collected during the day and use it at night.
Alternatively, you can utilize a concept known as Net metering. Net metering allows you to connect the solar panel to the electricity grid. The excess energy can be directed to the grid and used at night when there is no solar energy.
Some manufacturers allow you to use the energy collected from the sunlight and use electricity when the battery is depleted. The issue is that net metering is not available everywhere, and its future is uncertain. This leaves installing solar batteries as the only option if you have an AC unit.
Which are better, off-grid or grid-tied solar panels for AC?
You can use either off the grid or grid-tied solar panels for an AC. The difference is that you will pay some electricity bills with grid-tied solar panels.
Off-the-grid solar panels operate by solar energy only. You can connect the solar panels to powerful solar batteries with the capacity to power AC units. This will depend on the size of your AC unit. If you have a 1.5 Ton AC unit, you will need a solar battery with 600Ah.
If your AC unit serves your office space where you operate only during the day, you do not have to install a solar battery. However, a solar battery will help keep your AC unit running in case of a power surge.
Grid-tied solar panels can also power AC units efficiently.
The solar panel is connected to the electricity grid. When excess energy is collected during the day, it is stored in the grid and used to power the AC unit. Once the energy collected from the sun during the day is depleted, the grid switches directly to electricity use.
With the grid-tied solar panels, your AC will run during the day using solar energy and electricity energy during the night. Grid-tied solar panels will help reduce the amount you would have paid if running the AC unit on electricity alone. The problem is that grid-tied solar panels are not available everywhere.
Both off the grid and grid-tied solar panels can be used to power an AC unit and reduce the electricity bills by more than 50%.
An AC unit is a power-hungry device. It will consume more than 3000kwh if you use a standard size AC unit of 1Ton. This makes the electricity bills associated with AC units very high.
Luckily, more people are embracing solar as a form of energy. If you have powerful solar panels, you can install a solar battery and enjoy free energy from the sun. Alternatively, you can take advantage of the latest innovation known as net metering, where you connect the solar panel to the electricity grid. The moment energy collected from the sun is depleted, your AC unit can run on electricity.
The amount paid on grid-tied solar panels running AC units is much lower than what would have been paid if you run AC units on electricity alone.
Eng. Matthew Joseph Nandirio is the Founder of walkingsolar.
After graduating from the University of Houston in 2002, matt started working as an electrical and electronic engineer for several multi-national solar energy companies.
He has a wide range of experiences including solar system requirement analysis, planning, maintaining, debugging and even solar device development through research.
He now shares his 20 years of expertise through his articles on the walkingsolar website.
Further, he is also the author of two books on Solar Technology, “Solar Power for Villages” and “DIY Solar System for Dummies”.