Solar inverters and normal inverters also known as UPS are devices that that aids at increasing the efficiency of your home power system. Since UPS inverters are mostly grid-tied, they have been used in ages to protect devices that are easily damaged by power outages.
UPS inverters provide backup power to devices like computers to allow them shutdown safely in case of sudden power loss.
Due to the dire need of cheap source of energy, people are shifting from electricity dependence to use of solar energy. Solar energy is collected in form of DC but devices use AC to run. To aid in the convention process, solar inverters are essential.
Solar inverters are connection between the solar panel, charge controller, and a solar battery. They also have also have the capacity to hold some backup power used to power appliances.
To answer our main question of whether you can use a solar inverter in place of a UPS, we will have to look at the differences between the two devices. However, to give you a sneak pick, you can absolutely use a solar inverter as a UPS. You will however need to make a few adjustments to ensure the intended purpose is fulfilled.
What is the difference between solar inverter and UPS inverter?
Differentiating between the different types of inverters available and their specific use can be a lot of hustle for many people. Luckily, we are here for you.
We will use the basics, capacity, application, pricing, and connection aspects of solar inverters and UPS to show the difference between the two.
| Specification | Solar inverter | UPS |
| Basics | Converts DC into AC | Powers delicate devices incase of sudden power outage |
| Capacity | Large capacity device | Low capacity device |
| Connection | Stand-alone | Grid-tied |
| Application | Used in areas with frequent power outages | Used in areas with less power outages |
| Response speed | 500miliseconds | Less than 1millisecond |
| Design | Has a battery backup | Has both a battery backup and a charge controller |
Basics: Solar Inverter Vs. UPS inverter
A solar inverter devices main purpose is converting DC into AC used to power devices. UPS on the other is a device that holds some power used to protect delicate devices as they shutdown in case of sudden power outage.
Connection: Solar Inverter Vs. UPS Inverter
A solar inverter is connected separately from the solar panel, charge controller and a solar battery. It uses the charge from the battery to power devices.
UPS is grid- tied to the main home system. This however depends on the region you come from. UPS Inverter comes with an inbuilt charge controller.
Capacity: Solar Inverter Vs. UPS Inverter
Solar Inverter come in different sizes and capacities of between 10kW-100kW. They however cannot hold any energy but use that of the external battery.
UPS on the other hand has the capacity to hold some charge used as backup for devices. They can power an appliance for 10-30 minutes depending on the brand.
Application: Solar Inverter Vs. UPS Inverter
Since solar Inverters are connected to an external battery backup, you can use the inverter in areas that experience power outages. What k mean is that the battery will hold dome charge that can power appliances when need be.
UPS Inverter is grid- tied and cannot power a device for more than 30minutes.
Other differences between the two I’d n the response time. A solar inverter does not automatically switch on the power to run appliances in case of a sudden power outage. They have a switch which you use to turn on the device. UPS on the other hand turns on automatically when it detects a power outage.
How do I convert normal UPS to solar UPS?
From the differences described above, you can tell what you need to ensure an inverter fulfill a UPS purpose. For you to convert an inverter you will need a;
- Solar panel
- Solar battery
- Charge controller
- Solar Inverter and
- Some expertise.
Step 1: Selection of a solar battery
When selecting a solar battery, calculate the amount of output in your home. If you have large appliances like refrigerators and washers, then you might need more than one battery.
Standard deep cycle batteries come in 12V and 50Ah. This capacity cannot power a home the whole night.
You can use C ratings of solar batteries when choosing batteries. If your load output is large. Buy a battery rated 20C.
Step 2: Selection of charge controller
Also depending on the size of the battery you choose, you can find a charge controller to fit the use. There are two types of charge controller: MPPT and PWM. Each controller has its unique properties that make suitable for its purpose.
Step 3: Inverter selection
Solar Inverter come with a capacity of 10kW- 100kW. Depending on the size of the load output, you can choose an inverter within that range.
The rating on Inverter is indicated at the back of the device.
Step 4: Solar panel selection
Solar panels are rated in wattage. The indicated Watts however cannot be used when selecting a solar panel. Factors like weather condition and state of the panel determines the amount of current a solar panel produce.
To calculate the wattage you will need to measure the voltage and the amperes if the solar panel using a Multimeter. The wattage is found using the formula
Voltage × Amperes = Wattage
Ensure you match your load output with the input.
Step 5: Wiring
Connecting the setup is where a problem arises. If you have a little knowledge about inverters, you can use this video to connect the components. Alternatively, you can hire experts to do the wiring.
Eng. Matthew Joseph Nandirio is the Founder of walkingsolar.
After graduating from the University of Houston in 2002, matt started working as a Solar Electrical 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”.