What Is The Difference Between Off-grid And Grid-tied Solar Systems

Off-grid photovoltaic power plants store solar power in batteries, and then convert them into household voltage through inverters. The grid-connected power station refers to the connection with the mains. The grid-connected photovoltaic power station has no electric energy storage device, and is directly converted into the voltage required by the national grid through the inverter, and is given priority for home use. sold to the country.

1. Grid-connected photovoltaic power station

Grid-connected means that it must be connected to the public grid, that is, the solar power generation, the home grid, and the public grid are linked together. This is a power generation system that must rely on the existing grid to operate. It is mainly composed of mono solar panels and solar inverters. The output of solar panels is directly converted into 110V/220V AC power by the inverter and supplies power to household appliances. When the power generated by solar energy exceeds the power used by household appliances, the excess electricity will be delivered. To the public grid; and when the solar power generation can not meet the use of household appliances, it is automatically supplemented from the grid. And this whole process is intelligently controlled and does not require manual operation.

Since this photovoltaic power generation system does not require the use of batteries, the cost is greatly saved. In particular, the new grid-connection policy issued by the state has clearly stated that household photovoltaic power stations can be connected to the grid for free, and excess electricity can also be sold to power companies. From the long-term perspective of investment, according to the 25-year service life of the household photovoltaic power station, the cost can be recovered in about 4-7 years, and the remaining ten years are earned. Therefore, if you want to save electricity expenses and provide convenient power supply, you should choose a grid-connected solar power generation system, which is also the mainstream method at present.

2. Off-grid photovoltaic power station

This is also called an independent photovoltaic power station. It is a power generation system that operates independently without relying on the power grid. It is mainly composed of solar panels, energy storage batteries, charge and discharge controllers, inverters and other components. The electricity emitted by the solar panel directly flows into the solar battery and is stored. When it is necessary to supply power to the electrical appliance, the DC current in the battery is converted into 110V/220V AC by the inverter, which is a repetitive cycle of charge and discharge. This kind of power generation system is widely used because it is not restricted by regions. It can be installed and used as long as there is sunlight. Therefore, it is very suitable for remote areas without power grids, isolated islands, fishing boats, outdoor breeding bases, etc., and can also be used as frequent power outages. Regional emergency power generation equipment.