As of today, you can use solar panels for multiple applications. Hence, they allow you to lead the lifestyle you want. What makes it even better is that it produces green energy. So, you do not have to worry about depleting the resources or putting extra pressure on the Earth.
However, with so many panels available in the market, it can be quite confusing for a customer. Each brand on the market would also highlight several features that make it unique. How, then, do you decide what to buy? The voltage a solar panel produces is one thing to look for.
How Many Volts Does A 300W Solar Panel Produce?
The volts a solar panel produces depend on the amount of energy it receives from the Sun. However, a typical 300W solar panel would produce 240 volts of electricity under optimum conditions. When measured in amperes, this is equivalent to 1.25 amps.
Factors Affecting The Voltage Of A Solar Panel
Under usual circumstances, solar panels are able to produce consistent outputs with respect to voltage. It does not even change too much with the varying intensities of sunlight. However, the current it produces will change with the intensity of light.
This is not to say that you will never notice that the voltage of your solar panels changes. Here are some factors that might be affecting its voltage:
Clarity Of The Skies
You would notice that the voltage of your solar panels is nearly constant even as the current varies if you plot a PV graph. However, this is true only if the sky above the solar panels is clear. However, assume that a tree has covered the panels.
In this case, you would notice that the voltage of the solar panels changes. It is due to the nature of the materials it is composed of. To avoid this, manufacturers use bypass diodes. It ensures that you get optimum output even if some parts of the solar panel are shaded. The voltage may also depend on the temperature of the panels.
Charging Cycle Of The Battery
There are four stages of battery charging that you should know and the voltage varies with each of them. These are as under:
This is the first stage of charging and it begins when the solar panels get sunlight. This allows the panels to put energy into the battery. Once the batteries get electric energy, the voltage begins increasing.
After the batteries reach a predetermined voltage, they enter into this stage. The voltage depends on the kind of battery that is used. They only get out of this stage after a fixed time or after the amperes reduce.
This stage also causes a fixed voltage according to the programming of the controller. Usually, this stage occurs once the batteries have been completely charged. Since the controller determines the voltage in this stage, it is vital that you program it correctly.
This stage occurs from time to time. The battery is overcharged under control and it is used for maintenance. This is because some batteries do not function properly after some time. They do not give all the current they are supposed to. Equalization is performed to avoid this.
What Should You Do When The Voltage Is Too Low?
Now that you know what to expect from your solar panels, you would be able to tell when the voltage is too less. If such a situation occurs you can do the following:
- Ensure that nothing is blocking the panel. To do so, you will have to examine the solar panel physically. Do not worry, you can do it safely, provided you are careful. If something is blocking it, you can try to remove it.
- After you have looked at the panels for any blockage, you can look at the connections. You can do so when there is no sunlight on the panels. This is to ensure your safety. You can check for signs of corrosion. If you find any, you can use the right spray to clean it.
- Next, you can use a thermal camera. If you do not have this gadget, you can easily buy the ones that are budget-friendly online. When you check the panels, you will see a thermal output. You might wonder how this is going to help you with your solar panels.
Well, it will help because you will be able to see anything that resists the flow of current as heat on the camera. Hence, you will be able to understand what causes the low voltage.
Should You Go For High Or Low Voltage?
All this talk about voltage might have you wondering what you should go for – high or low voltage. You can have a look at the disadvantages and advantages of each one and decide for yourself.
Advantages of high voltage solar panels:
- It is more potent and consistent. As constant energy can be used as a backup in case of any emergency.
- Usually, higher voltage panels have volts from 60- 72 volts. Hence, high voltage has more energy than low voltage panels as you can use it for larger loads.
- High voltage solar panels permit more power output per panel. Since it doesn’t require many panels.
- Moreover, it works better with inverters than others.
- It generates energy faster.
- High voltage panels can save many watts of energy.
Disadvantages of high voltage solar panels:
- More expensive than low-voltage solar panels.
- Sometimes higher voltage systems lead to a high risk of shock.
- Installation costs are also higher.
Advantages of low voltage solar panels:
- Low-volt panels are cheaper than others.
- It can generate power easily even if it does not have enough sunlight.
- It is quite easy to install and the cost for installation is also lower.
- Though it doesn’t produce more energy than a higher voltage panel, it works great for smaller homes.
Disadvantages of low voltage solar panels:
- The low-voltage panels may not generate sufficient electricity. Low energy production is the major disadvantage of low-volt solar panels.
- It does not match any gadget that needs a lot of energy.
Hope you now know everything you need about 300W solar panels. You would also know why your voltage changes unexpectedly and how to fix it. However, you should be careful when you check out connections. If you are unsure, you can always call an expert for help.
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”.