Have you ever wondered how a solar system works? In this article I’ll explain and simplify the process.
There are two main components of a solar system;
- Solar panels
- Inverter
Solar Panels
Solar panels are generally installed on a rooftop. They are used to convert the suns energy into DC electricity. The amount of electricity generated depends on multiple things including; panel efficiency, number of cells per panel, number of panels, tilt and direction of panels, temperature, shading and dirt/dust build up.
North facing panels are the best for generating the maximum yield, but sometimes it is not possible to have all panels facing north, or even any of them. East and West facing panels are also a good option, generating roughly 15% less than North facing panels. Depending on your usage of power it can often work out better to have East/West facing panels if you use more power in the mornings and afternoons, therefor saving you from importing electricity at those times.
The tilt will also affect the amount of power generated. The panels should have a minimum of 10° tilt to allow for self-cleaning with rain. The average roof pitch is around 20° which works well. 31° would be ideal for most of the Mid North Coast, but often it is much easier to install on the roof at 20° which will have a very minimal difference to 31°.
Inverters
There are two main types of inverters; String inverters and micro inverters. String inverters are normally mounted on a wall somewhere close to your switchboard. They should be protected from excessive sunlight as this can shorten their life due to heat. String inverters are a more common option as they are cheaper than micro inverters and work well if there are no shade issues for the solar panels. The downside of a string inverter is where there is shade. If one panel is partly shaded then it can limit the electricity flowing through the whole string and significantly reduce the output of the inverter.
Micro inverters are small inverters that are mounted under each solar panel. So if you have 20 panels then you need 20 inverters. Micro inverters convert the DC electricity generated by each solar panels into AC electricity immediately, then the cabling running down to your switchboard is only running at 240V AC. In a string inverter system this cabling can be running up to 600V DC. The main benefit of micro inverters is that they maximise the amount of power generated by each panel. If one panel is partly shaded then only the one micro inverter will produce less power and all the other panels will be unaffected by it. Using micro inverters will increase the cost of a system by about 25%.
From the inverter the wiring is then run to your switchboard. The electricity generated by the solar system is then used in your home to power your electrical appliances like TV’s, lights, washing machines and dishwashers. This saves you from paying to import electricity. Any excess electricity that your solar system is producing and you are not using in your home will be exported to the grid. Most retailers will pay you per kilowatt hour for the electricity that you export. At the moment (27/1/2021) the rates for feedin tariffs in NSW vary from $0.00 to $0.21 per kilowatt hour so it pays to find the best deal for you.
Savings
To maximise the savings on your electricity bill it is best to use as much power as you can while the sun is shining. In summer this is easier as the sun is out longer and your solar system will be generating power for a longer period each day. A lot of modern appliances have timers, so you can run things like washing machines and dishwashers during the day when the sun is shining. You can even set up some smart systems to turn your air conditioner on an hour or two before you get home in the afternoon so that the house is cool and it’s powered by the sun.
If you have any questions please feel free to contact me and and we can chat.
If you’d like a quote for a solar system and installation please get in touch.
Luke Warren
Waz Electrical
0438 952 200