How To Test Solar Panels Without Sun [Step By Step Guide}

Solar panel manufacturers need a way to test how their solar panels perform in various scenarios and conditions, which is why they need a way to simulate how the panel performs when there’s no sunlight!

And in this blog post, we will show exactly how to test solar panels without sun sing household items.

But before going into the actual step by step guide, first, you need to understand how solar cells work.

Table of Contents

How Do Solar Panels Work?

In order to understand how to test solar panels without sun, it’s important to know how a typical photovoltaic cell works.

There are two types of cells: crystalline and thin film, but for this blog post, we will be focusing on crystalline cells, which make up over 80% of the market share in installed capacity.

Solar panels working concept is the following:

Sunlight (photons) strike the cell, releasing electrons inside of it.

The freed electrons are pushed to one side of the solar panel by a positively charged strip where they collect in an electric field until they have enough energy to escape as electricity.

This electricity is then supplied to the solar inverter to convert it into a usable AC current to power your appliances.

Related article: How Do Solar Panels Work?

How To Test Solar Panel Wattage

To test your panel’s wattage, all you need to do is to expose your solar panel in direct sunlight and measure how much voltage and amperage is currently being produced by the solar panel.

Measuring with a voltmeter, you will need to measure how many volts are pushing through your meter (more than 12V means it’s working).

Then use an ammeter to count how many amps of current are running through your electrical system.

After that, just multiply the Voltmeter output (Voltage) by the Ammeter output (Amperage) and you will get your solar panel wattage.

Wattage = Volt * Ampere

Related article: Why Do Solar Panels Have A Peak Power?

But Without Sunlight, How To Test Solar Panels?

Well as mentioned before, solar panels work by using the LIGHT PHOTONS into electricity.

We didn’t say sunlight in particular, as any powerful lamp can do the trick.

Yes, artificial light won’t be as efficient as sunlight because sunlight has way more photons with different energy levels.

However, because we just want to test if the solar panel is working or not, we can use artificial light.

So here is how to test your solar panels without sun:

Connect your solar panel to a voltmeter
Bring in powerful floodlight(s), preferably an incandescent lamp
Place the artificial light close to the solar panel
Watch your voltmeter reading

If your solar panel is working, then the voltmeter will have a reading.

It will be a very small reading, as the lamp won’t provide the solar panel with enough photons, so it won’t be able to produce a lot of electricity for the voltmeter.

It’s important to mention that if your voltmeter outputs 0, this doesn’t mean that the panel isn’t working.

Sometimes, the lamp you are using will just be too weak to stimulate the panel’s atoms, and only very little electricity is produced, so the voltmeter won’t be able to read it.