The choice of photovoltaic power station on grid or off grid

If you install a solar photovoltaic power station in your own home, should it be on-grid or off-grid? Do you need batteries?

To put it simply, off-grid photovoltaic power plants store solar power in storage batteries and then convert them into household 220V voltage through inverters.

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 household use. The household’s unused electricity can be sold to the country.

Grid-connected photovoltaic power station

Grid-connected means that it must be connected to the public power grid, that is, solar power generation, household power grids, and public power grids are linked together. This is a power generation system that must rely on the existing power grid to operate.

It is mainly composed of solar panels and inverters. The solar panels are directly converted into 220V alternating current by the inverter and supply power to the household appliances. When the power generated by the solar energy exceeds the power used by the household appliances, the excess electricity is sent to the public Grid; and when solar power can not meet the use of household appliances, it will automatically be supplemented from the grid. And this whole process is intelligently controlled, without manual operation.

Since this photovoltaic power generation system does not need to use batteries, it greatly saves costs. From a long-term perspective of investment, based on the 25-year service life of a household photovoltaic power station, the cost can be recovered in about 6-10 years, and the remaining ten years will be earned.

Therefore, if you want to save electricity costs and provide convenient power supply, you can choose a grid-connected solar power system.

However, grid connection also has its disadvantages, that is, photovoltaic power generation cannot operate when the public grid is out of power. However, if the grid-connected inverter is replaced with a smart micro-grid inverter (a hybrid inverter of grid-connected and off-grid), the power station can operate normally.

So, how can we store the electricity generated during the day and use it at night? This requires the addition of a controller and a battery. During the day, the controller stores the electricity generated by the photovoltaic in the battery, and at night the controller releases the electricity stored in the battery for lighting.

Off-grid photovoltaic power station

This is also called an independent photovoltaic power station. It is a power generation system that does not rely on the grid and operates independently. It mainly consists of solar panels, energy storage batteries, charge and discharge controllers, inverters and other components.

The electricity generated by the solar panels flows directly into the battery and is stored. When it is necessary to supply power to the electrical appliances, the DC current in the battery is converted into 220V AC power through the inverter. This is a repeated cycle of charging and discharging.

This kind of power generation system is not restricted by region and is widely used. It can be installed and used in places where 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. Emergency power generation equipment in the region.

This kind of system must be equipped with storage batteries and occupies 30-50% of the cost of the power generation system.

For families in areas without power grids or areas with frequent power outages, it is also very practical. Especially in order to solve the lighting problem during power failure, DC energy-saving lamps can be used, which is very practical.

Therefore, the off-grid power generation system is specially designed for use in areas without power grids or areas with frequent power outages.

Conclusion

To photovoltaic power station put it simply: Grid-connected does not require batteries, off-grid requires batteries.