How do solar panels work?

Posted 13 Apr '18
How do solar panels work?

How do solar panels work?

DID YOU KNOW that enough sunlight hits the earth in ONE hour to power it for an entire year?!  We use a lot of power in our day to day lives and the sun is up to the task.  It's no surprise that solar panels are becoming such a popular way for people to generate their own (clean!) electricity.  But just how do solar panels work getting the energy from  the sun into your home? 

The first thing you need to know is that solar panels rely on light from the sun, not heat so here is a quick rundown of the flow:

  1. Photovoltaic (PV) cells in a solar panel convert sunlight into an electric current. 
  2. The current passes through an inverter to make it compatible with your home’s wiring and appliances (this is called an alternating current or AC).
  3. Alternating current is channeled into your home's wiring and is available for you to use as electricity.
  4. Any extra electricity is wired to the electrical grid (more on that later) or, if you have an energy storage system, some may be stored in a battery for later use.

1. PV cells convert sunlight to an electric current

Our sun is a natural nuclear reactor. It releases tiny packets of energy called photons, which travel the 93 million miles from the sun to Earth in about 8.5 minutes.   Each solar panel is made of photovoltaic, or PV, cells. PV cells convert photons (sunlight) into voltage and current (electricity).   Multiple cells make up a solar panel, and multiple panels (modules) can be wired together to form a solar array. The more panels you can deploy, the more energy you can expect to generate.

To get the electricity from those solar panels to power a home, a couple of steps are needed after the PV cells do their job. First, the electrical current needs to match the type of electricity your home uses, then that current needs to get to your home’s wiring system.

2. An inverter converts DC to AC

There are two kinds of electrical current - Direct Current (DC) and Alternating Current (AC).  Solar panels generate DC, but our homes and appliances are made to use AC. An inverter is a device that uses electronic circuitry to convert DC to AC. Some solar panel setups have a single inverter (often called a “string” inverter) for the entire system and some have a microinverter attached behind each panel. Once the electrical current goes through the inverter, you have a current that can be used to power your home!

3. You use electricity - just like you do now

The electric current is wired from the inverter into your home’s existing wiring.  It works just like your electricity does now - you don’t have to change a thing.

Now that you know how powerful the sun is, you may be wondering what happens if your solar panels produce more electricity than you need. To understand what happens next, you need to know something about the grid system.

4. Extra electricity goes back to the grid or charges a battery

The Grid

Rooftop solar panels utilise the grid system, both to offload extra electricity and to give your home backup electricity as needed.

Being on the grid allows you to use exactly as much electricity as you need, when you need it, and send any excess back to the grid. Solar panels generate electricity when the Sun is up, but since most people use electricity at night, it’s important to have access to power from the grid any time. 

In most residential set-ups, excess power created by your solar panels is fed back into the grid, meaning your utility may credit you the next time your power bill arrives

If you would rather have some more energy independence, however, you may be able to install a battery.

Energy Storage

Batteries are available for some rooftop solar setups. Including a battery allows you to store the extra energy you generate when the Sun is shining for use later (like at night, on cloudy days, or in the event of a power outage).   To read more about battery storage systems see our previous BLOG.

And there you have it.  Now you know how solar panels work, you will have a greater appreciation for those shiny panels you see on rooftops.  

Don't forget that it always pays to choose premium quality solar panels over cheap and inferior alternatives. We’ve covered this in a previous BLOG, but basically, premium panels will have cells that contain purer silicon (the higher the silicon grade, the longer the solar cell will last and the better it will perform in converting the sun’s energy to electricity ), less deviation between the cells (eliminating mismatch) and higher efficiency and longevity. This all combines to give you a smoother solar energy experience and one which is more likely to meet and exceed your savings expectations.

For me information, send us a message and one of our solar technicians will be in contact.