Not sure what backup or solar system you need?
First question you need to ask yourself is what will the purpose of the system be.
- Do you only need backup for when the grid (Eskom) is down;
- Do you want to reduce your electricity bill.
For both the options above you will need a inverter. There are 3 main types of inverters:
1.Off-grid inverters;
Off-grid inverters are designed to work alone and cannot synchronise with the grid. They connect to the property in place of grid power and cannot work in conjunction with it. It draws power from the battery, converts it from DC and outputs AC.
2. Grid-tied inverters;
Grid-tied inverters are designed to connect to your home to supplement mains (Eskom) power. When there is solar energy to use, the system will deliver it to your property. When there is insufficient energy to deliver, the system will switch back to grid power.
Grid-tied inverters work with mains to provide energy wherever possible. They have the processing intelligence to know when to deliver power and when to not deliver it and will synchronise power delivery with grid power.
An on-grid inverter converts solar power DC which is constantly varying and feed it into the mains power supply. It synchronises its output voltage and frequency to the mains power supply it is connected to. As the power of the solar increases, so does the output but it can do this at leisure. There is no forced power demand or instant requirement, it simply puts power though as and when it can.
3. Hybrid inverters;
Hybrid inverters are exactly as the name states - a hybrid between a grid-tied inverter and off-grid inverter. Hybrid inverters have all the benefits of a grid-tied inverter with the added benefit that batteries can be connected to these inverters.
If you only need a backup power supply you will need the following:
- An inverter (main type of inverters are grid-tied inverter, off-grid inverters and hybrid inverters, for this application all of them will do the job. Off-grid inverters are generally cheaper). Need help on the size of the inverter you need - click here;
- Batteries, there are 2 main types - litium-ion and gel batteries. More information on the differences here. Info on the size of the battery bank you will need can be calculated here; and
- All the necessary extras such as battery cables, lugs for these cables, battery disconnector and single phase AC disconnector.
If you decided you want to reduce your electricity bill, you will need the following:
- An inverter (main type of inverters are grid-tied inverter, off-grid inverters and hybrid inverters). Off-grid inverters are generally cheaper, but for this application hybrid inverters are the superior option. Need help on the size of the inverter you need - click here ;
- Solar panels. Two main types of panels are mono-crystalline and poly-crystalline (which type of panel do i need?). The total wattage of panels you need can be calculated here;
- All the necessary extras such as solar panel cables, solar panel rails, solar panel brackets to connect them to the rails, connectors for the solar panel cables (called MC4 connectors), solar panel disconnector and single phase AC disconnector.
- OPTIONAL: while these systems will ensure you reduce your monthly electricity bill by use of solar panels, these panels are powered by the sun. Thus during the night you will make use of grid electricity (Eskom). For this reason many customers may choose to include batteries in this system. If you choose to add batteries, the size of battery bank can be calculated here.