HOW DOES IT WORK

In this section we want to give you a short and simple overview of how a solar project works and what the different components like solar panels and inverters do.

Let’s start with the solar panels. Sometimes solar panels are called solar modules. They’re the same thing. The solar panels are the flat panels with a glass cover and a metal frame that contain the solar cells. See the photo on the side for a solar panel. Now the solar cells inside the panel – the small blue squares – that’s what produces electricity.

Basically whenever sunlight shines onto a solar cell it makes electrons travel from the back of the solar cell to the front of the solar cell. On the front of the solar cell you can see thin metal lines. These are contacts and wires which collect the electrons. And that, right there, electrons travelling through a wire, that’s electricity.

Now one solar cell only produces a little bit of electricity. That’s why a solar panel has up to around 100 solar cells one behind the other to make more electricity. This is just like how many electrical devices like flashlights have not just one but multiple batteries one behind the other.

In a solar project we then connect many solar panels to each other so that again, we produce more electricity. This is the same principle like putting multiple batteries one behind the other again.

The next step then, is the inverter. What does the inverter do? The thing is, solar cells and solar panels produce direct current (DC) electricity. This means the electricity always flows in the same direction from plus (+) to minus (-). That’s the same thing as with batteries again. But this is not how our electrical grid works. Electrical sockets at home do not have a (+) and a (-) hole and it doesn’t matter which way around we put the plug in. That’s because in the electricity grid we use alternating current (AC). With alternating current the (+) and (-) poles change all the time. They change 50 times per second. And this is where the inverter comes in. To connect the solar project to the grid, we need to turn DC electricity into AC electricity. So what the inverter does, is that it switches the (+) and (-) poles of the solar project just like they switch in the electricity grid, at the same moment and at the same speed. This way you can then connect the solar project right to the electricity grid.

The last step is the connection to the electricity grid. When it’s a small solar projects (up to 30 kW) you typically connect the project in the same place where your electricity meter is. There will be a second meter then which counts how much electricity you have produced with the solar project. And this is what you get paid for then.  When it’s a larger project (around 100 or 200 kW) you often need a strong electricity connection and that’s when you have to install a small transformer.

For more information check out these links:

Solar cell: http://en.wikipedia.org/wiki/Solar_cell

Inverter: http://en.wikipedia.org/wiki/Inverter_(electrical)