Testing Solar Panels

How to Test Solar Panels - Accurately Measuring Solar Panel Output

Taking the time to test your solar panels is one of the best ways you can get a true reading of their actual power output. Given that the output and efficiency of your solar panels will have a drastic impact on the overall power capabilities of your solar power system, it makes sense that many people test their solar panels on a fairly regular basis.

If you would like to know how to test solar panels, you have come to the right place! We will explain how you would go about measuring both solar panel amperage and current. We will also explain how you can use a multimeter to test the voltage of your solar panels

Why is it Important to Test Your Solar Panels?

The power rating of a solar panel is given by the manufacturer and the number simply represents the amount of power that solar panel is capable of producing under the most ideal conditions. However, in reality, solar panels are rarely exposed to ideal conditions for more than a few hours per day.

Solar panel efficiency and power production can differ due to a variety of factors, including the number of peak sun hours in a day, shading issues, the outside temperature, the direction the solar panels are facing, the geographic location of the solar panels, and the particular season when the solar panels are being used.

Testing your solar panels allows you to get an accurate reading of how much solar power they are really generating. Not only would this allow you to adjust your expectations to more accurately reflect the true potential of your solar panels, it will let you know if you need to invest in more solar panels, or simply reposition the ones you are currently using.

Essentially, testing your solar panels will allow you to make sure that they are generating enough power to meet your needs and let you know if you need to reinstall them so you can optimize their performance and get the highest possible amount of solar electricity out of your system.

How to Test Solar Panel Output

Test your solar panels, you will need to perform a fairly simple calculation. Basically, you will need to multiply the volts and amps, as this will give you an accurate total wattage:Volts x Amps = watts So, to determine the power that your solar panel is generating, you will need to first measure the amperage and voltage.

Start by Noting the Power Rating:

One of the first things you will want to take note of is the actual power rating of your solar panels. As discussed above, this wattage rating will not necessarily reflect the amount of electricity your solar panels can generate, as plenty of variables can influence performance, but it is still useful information to have, as it will give you an idea of how well your solar panels are performing in relation to their maximum potential.

When solar panels are given a power rating, the number is based off a laboratory test, where the solar panel is exposed to an hour of simulated sunlight that measures 1,000 watts per square meter. During these tests, the solar panels are also kept at a constant temperature of 77ï‚° F, as temperature fluctuations can also impact performance.

So, if a solar panel has a power rating of 300W, that means it produced 300 watts of electricity after being tested in ideal conditions. Again, if you were to purchase this same 300W solar panel, it would likely produce less power than this, which is why it is important to test its performance for yourself.

Measure the Solar Panel Amperage:

To measure the amperage of your solar panel, you will need to use what is known as an amp meter. These are fairly affordable devices and they can be purchased at most hardware and automotive stores.

Once you have one, simply attach the meter to the positive and negative terminals of your solar panels. When testing, you will want to make sure that your solar panel is receiving the same amount of sunlight it would under normal conditions, so try not to move it from where it would normally be positioned.

Measure the Solar Panel Current:

To measure the current, you can use a multimeter. Again, these devices are affordable and worth investing in if you are running a solar power system. They can also be found at most hardware and automotive stores.

If you want to make sure you are getting an accurate reading, you will also need to use a variable resistor box. These devices allow you to get readings at different levels of resistance.

Calculating Solar Panel Output:

As mentioned above, you will now want to make a quick calculation to get the power output for your solar panel. Simply use the amperage and voltage readings your earlier tests revealed and perform the following equation: Volts x Amps = watts.

>Once you have calculated the real wattage of your solar panels, you can multiply this number by the average hours of sunlight you get per day: Solar panel watts x average hours of sunlight = daily watt-hours

Most people then take 75% of this total, as it helps account for the fact that the directness of the sunlight will not be consistent throughout the day. Sunlight tends to be at its most powerful and direct in the hours just before and after noon.