A complete solar panel comprises three main components, the panel, battery, and the inverter.
However, due to the high initial investments of owning these items, most people consider leaving out some components in their installations to cut off the costs.
For instance, if you have an off-grid setup, you can have a solar panel without the battery. However, that raises a concern.
A solar inverter is usually connected to the battery to convert the output current to an alternating current which is more compatible with most appliances.
Unfortunately, all solar panels produce a direct current which is not compatible with most appliances. As a result, you are likely to need an inverter.
But, can you use a solar panel and inverter without a battery? The short answer is yes, but there are a few things to consider. So, you better keep on reading to ensure that your solar panel setup is secure and reliable.
Can I use a solar panel and inverter without a battery?
In a typical solar panel setup, the panel connects to the battery system, which connects to the inverter on the other end. This is how there are designed; the panel converts the solar energy to power stored in the battery.
When you plug in an appliance, power is drawn from the batteries that pass through the inverter to convert to alternating current.
However, if you don’t have a battery, you cannot connect the inverter in the usual way.
The good news is that you can connect the solar panel and inverter directly. Even better, if you have a hybrid inverter, it will not only take in power from the panel and convert it but also store some in its inbuilt storage space.
Just a second before you jump over and start making the connections. The solar inverters are designed to operate within a specific amperage and voltage. That is why you are always told to consider the battery’s power before purchasing the inverter.
Obviously, the power generated by the solar panel will exceed the power limit of the inverter. Actually, if you just use these two devices directly, the inverter will start beeping, which signifies no current flow.
In simple words, for you to use the solar panel and inverter without the battery, you must step down the voltage. Below is the practical bit to help you understand better.
How to connect solar panel and inverter without battery
Step 1: Check the voltage of the panel and inverter
The inverter has a voltage limit that it can handle. Let us assume the voltage limit of the inverter is 15 volts, and the voltage supplied by the solar panel is 18.7 volts.
Step 2: calculate the difference
to get the amount of power that needs to be stepped down, you should subtract the voltage of the inverter from the panel’s voltage.
18.7 volts – 15 volts = 3.7 volts
Step 3: Calculate the number of diodes needed
To step down, the power will be using diodes. The power stepped down by each diode is 0.6 volts.
To calculate the number of diodes required, we will divide each diode’s voltage to be stepped down.
3.7 volts / 0.6 volts = 6. 1667
However, we cannot work with a decimal value when referring to an object. Besides, the diodes used should be greater or equal to your value. Thus the total number of diodes used should be 7.
Step 4: Connect the diodes in a series
Take seven diodes and connect them in series.
Step 5: Connect the diodes with the panel and the inverter
Lastly, connect one end of the diodes to the panel and the other to the inverter. That is how you can use solar panels and inverters without batteries.
You can also check on this video which gives a demo of connecting the panel and inverter.
Why do you need an inverter for solar panels?
When we mention solar power, likely what comes to your mind is only solar panels. The truth is that the panels cannot power some of your devices all by themselves. There is a lot more that makes this system.
However, some of these components are likely to break your bank account due to their high costs. Fortunately, you can ignore a solar battery if you have an off-grid setup. But can you do the same for an inverter?
Unfortunately, an inverter is a must-have component to have solar power in some of your devices. To understand why you must have this component, let’s discuss how solar power is generated.
The power generation process starts with the solar panels with photovoltaic cells that absorb the solar energy and convert it to direct current.
The solar energy absorption takes place at night, and the amount absorbed highly depends on the quality of the sunlight and the number of solar panels.
This current is passed to the inverter, assuming that you don’t have batteries.
Inverter at work
An inverter is a rectangular-shaped power tool that takes the direct current from either the solar panel or batteries and converts it to alternating current. The inverted current is sent to a fuse box and later to the switchboard, which you can access.
Why is this current inversion necessary?
Power tools that include household appliances are designed to operate only using specific current types, either direct or alternating current.
In addition, most appliances tend to use alternating currents. In point of fact, in most homes, most if not all of their appliances use alternating current.
Thus, an inverter converts the power to a safe form to use.
However, in rare cases, you might not need an inverter if the devices are compatible with direct current. This happens mostly in industries. However, it will not cause any harm to check if the appliances use direct or alternating current to determine if you need an inverter.
However, if your panel is for home use, you will need an inverter.
Which is better, solar with or without battery?
A solar battery is used to store excess power, which can be drawn later when the panels cant generate more power due to lack of solar energy.
However, adding the battery into the system involves complex economics. First, its initial cost is quite high, and it consists of a lot of maintenance costs in the long run.
Do I mean that it is better to solar without a battery? Give me a second, and I will make everything plain to you.
If you have an off-grid setup, then you will need a battery. An on-grid design cannot access the grid’s power when it cannot produce the required power. As a result, you will likely experience blackouts at night or on a cloudy day.
However, if you have an on-grid, you can be sure of a reliable power source at any time. To help you understand, below are the advantages and disadvantages of having a panel without a battery.
Advantages of solar without battery
- Low initial cost
- Less labor is needed during installation
- Low maintenance
Disadvantages of a solar panel without battery
- You are likely to experience blackouts if you are using an off-grid setup
- You must step down the power when wiring the panel
- You need to have a hybrid type inverter, usually high cost.
Conclusion: The solar panel is better without a battery if you have an on-grid design. Nonetheless, you will have to step down the voltage when doing the wiring. Otherwise, you will need a battery for a reliable source of power.
In a nutshell, you can use a solar panel and inverter without a battery. However, the wiring process will be different. The inverter will be connected directly to the panel, which might bring an issue due to the voltage difference.
The inverter working principle is that the input power voltage should be within a specific limit, which is not the case because solar panels have high voltages.
Consequently, you must step down the voltage before connecting the inverter. We have discussed all that and even given calculation examples to ensure you have a less troublesome time.
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”.