Inverters can be grid-tied or off grid, pure sine or modified sine. The inverters here are all DC to AC inverters. They change the DC power produced by the solar panels into AC power that is normally used by your household appliances.
Grid-Tie Inverter
- Synchronizes with the grid to feed electricity produced back to the grid. MUST be pure sine inverter. If modified sine grid tie inverter are used, the inverter MAY fail or melt down the whole inverter.
- Simple(do not have to mess around with installation of a battery bank). Furthermore, batteries are very expensive. You will need a lot of batteries to store the power produced during the day for use in the night.
- You do not have to attach a charge controller when you already have grid-tie inverter. The inverter will regulate the power.
- However, if the grid goes down(power failure), the grid-tie inverter will automatically stop sending electricity into the grid. This is to protect the line man from electrocution from a supposedly dead line.
- Grid-tie inverters are more expensive than off-grid inverters.
Before buying a grid-tie inverter, please check with your state/country’s regulations regarding feeding electricity back into the grid. You may need to apply with the authorities or power companies for approval to put electricity into the grid. In some countries, feeding electricity into the grid is ILLEGAL.
Off-Grid Inverter
- Needs a battery bank. If the battery bank is full, no electricity will flow into the batteries. Hence, electricity is lost.(wasted)
- Needs a charge controller to regulate the voltage
Difference between Pure-sine inverters and modified sine inverters
- Some appliances may not run well with modified sine inverters. They prefer pure sine inverters.
- Pure-sine inverters are more expensive than modified sine inverters.