The way solar panels work may seem like magic!
All you need is panels on your roof and you can run your lights, TV, microwave, and washing machine.
Adding to this, once you’ve installed the solar panels it doesn’t cost you a cent to generate electricity.
It’s crazy to think that the sun, which is 93 million miles away, can power your home.
In fact, you can even make money by selling electricity to the main grid.
Well, solar panels don’t work by magic. It’s actually pretty simple science to take the sun’s energy and convert it into electricity.
How Solar Panels Work: Step by Step
The inner workings of solar panels can be hard to understand if you’re just reading the scientific explanation.
Let’s get rid of the complex science, and go through how a solar panel works in simple terms. Here is an easy step by step guide:
- Sunlight hits the solar panel cells. Solar cells are the main face of the solar panel.
- The sun’s energy energises electrons to make them move around the solar cells.
- These moving electrons create an electric current.
- Electricity then flows into a wire to a battery or power inverter
- An inverter converts the direct current (DC) electricity from the solar panel into alternating current (AC) electricity.
- AC electricity is then used to run appliances and electronics, or flow into the main grid. When electricity is sent to the main grid, it is recorded on the electricity meter and you are credited for supplying electricity
The Science Behind Solar Panels
Let’s go a little deeper into the science behind how solar panels work.
Solar panels are built from lots of smaller solar cells. This is what makes up the main black surface of a solar panel.
Each solar cell is photovoltaic, this means they are able to convert sunlight into electricity. Photovoltaic cells are made from two pieces of semiconducting materials sandwiched together. Usually, this is silicon.
In order to work, these cells need to create an electrical field when hit by sunlight. The two layers of semiconductor are oppositely charged. One side is positive and one side is negative. Just like the opposite poles of a magnet which create magnetic fields.
To create this positive and negative semiconductor, phosphorus is added to the top layer of silicon to increase the number of electrons and create a negative charge. The bottom layer of silicon is mixed with boron to reduce electrons and create a positive charge.
With the photovoltaic solar cells built in this way, they are ready to receive sunlight.
When the sun’s photons (sunlight) hit the solar cell it knocks electrons free from their atoms.
The electrons are now moving freely to create an electric field. This electrical field forces all the electrons to flow in the same direction, this is called an electrical current.
Now all that’s left to do is to collect these electrons using metal conductive plates at the edge of the cell. Then they can be sent down a wire in a direct electrical current to use as electricity.
From this point, it is up to your electrical system to determine how you use the electricity. In a house, it would flow straight into a power inverter which converts the direct current supplied by solar panels into alternating current which is supplied by the main grid. Once this DC to AC conversion is made you can run appliances or send excess into the main grid.
If you have an off-grid electrical system, like in an RV or cabin, you will need to store the solar panel electricity in a deep-cycle battery. Then you can draw DC power from your battery using a power inverter to run your appliances.
Advancements in Solar Panel Technology
As you can imagine, the technology is always improving and you will see more solar power appear throughout this century.
Recent advancements are making solar panels smaller and more powerful. For example, you can now get flexible solar cells which are thinner than a piece of paper. These are used to make lightweight, thin, and flexible solar panels which are 90% lighter than the glass ones you see on roofs. These are very popular to use in portable solar panels or to save weight on vehicles like boats and vans.
In addition, you can now find more powerful solar panels which can generate 500 watts output from a single panel!
Advantages and Disadvantages of Solar Panels
Solar panels are amazing pieces of equipment. You set them up in the sun and leave them to do their thing.
The benefits of solar panels are quite clear for everyone to see. But we should also look at the drawbacks to using a solar panel?
Advantages of Solar Panels
- Generate free electricity
- No carbon emissions
- Eco-friendly
- Provide off-grid electricity supply
- Reduce electricity bills
- Make money selling electricity to main grid
- Maintenance free (except for cleaning)
Disadvantages of Solar Panels
- Expensive to install
- Don’t work at night
- Reduced output when not in direct sunlight
- Only produce top output during peak sunlight hours (4 or 5 hours a day)
- Unreliable amount of energy production
As you can see, if you can afford to install solar panels then it is a brilliant way to add extra electricity and reduce reliance on the main grid. Plus you can produce electricity in remote locations.
Unfortunately, like most renewable energy sources, you are at the mercy of your environment. For example, you can’t generate electricity at night. Plus power output will be reduced in cloudy or shady situations.
Do Solar Panels Work When There is No Sun?
Solar panels will still work when there is no direct sunlight. The most common reason for this is cloud cover. The good news is that sunlight will still pass through the clouds and hit your solar panels. If sunlight didn’t pass through clouds we would be in complete darkness. Unfortunately, the amount of energy is severely reduced meaning your solar panels won’t generate as much electricity. In fact, it can reduce power output by 70% or more!
Do Solar Panels Work at Night?
No, solar panels do not work at night. Solar panels need to be hit with sunlight to generate electricity. You might be wondering if moonlight can run a solar panel. Well, technically speaking it can as the moon is simply reflecting sunlight to earth. But by the time the light reaches earth, it will be too weak to generate any noticeable solar power.
You can easily feel the difference in power. Imagine standing in direct sunlight, you can literally feel the warmth from the sun. When you stand under a bright full moon you can’t feel the warming energy.
Do Solar Panels Work in Winter?
Yes, solar panels will still work during the winter. The amount of electricity produced will be reduced for a number of reasons.
- The sun is further aways so the energy hitting your solar cells is reduced even in direct sunlight.
- The days are shorter, giving your solar panels time to gather sunlight.
- Bad weather results in more cloud cover and adverse conditions like ice and snow.
Always ensure you keep your solar panels clear from any obstructions like ice, snow, and leaves.
Do Solar Panels Work in Snow?
A solar panel will not work when it is covered in snow as no sunlight will hit the solar cells. You must remove any snow from the face of the panel. If there is no snow on your panel then it will still work while it is snowing. However, power output will be severely reduced due to the heavy cloud cover.
Do Solar Panels Work in the Rain?
Yes, solar panels will work in the rain but power output will be severely reduced due to the heavy cloud cover and water obstructing sunlight.
Rain can be good for solar panels in the long run as it helps to clear away dust and dirt to keep them clean. Remember, a clean solar panel is an efficient solar panel.
Final Words on How Solar Panels Work
As you can see, solar panels are relatively simple in the way they work.
There aren’t moving parts, like you would find in a wind turbine, just a flat panel made up of solar photovoltaic cells.
When these solar cells are hit by sunlight they create an electric field which is sent down a wire as electricity.
It’s a free and maintenance-free way to generate electricity anywhere there is sunlight, whether that’s at home or at the top of a mountain. As you can imagine, space stations and satellites rely heavily on solar power. It’s even more efficient in space with pesky cloud cover, plus they’re even closer to the sun!
