The difference between on-grid， off-grid ，hybrid system
On-grid power generation system
The photovoltaic on-grid system consists of components, a grid-connected inverter, a photovoltaic meter, a load, a two-way meter, a on-grid cabinet and a power grid. The photovoltaic module generates direct current from light and converts it into alternating current through the inverter to supply the load and send it to the grid.
There are two main Internet access modes for on-grid photovoltaic systems, one is “self-use and surplus electricity is connected to the Internet”, and the other is “full Internet access”.
Generally, distributed photovoltaic power generation systems mainly adopt the “self-consumption and surplus power grid” mode. The power generated by the solar cells is given priority to the load. When the load cannot be used up, the excess power is sent to the power grid. When the power supplied to the load is not enough, the power grid and Photovoltaic systems can supply power to loads simultaneously.
Off-grid power generation system
Off-grid photovoltaic power generation systems operate independently without relying on the power grid. They are generally used in remote mountainous areas, areas without electricity, islands, communication base stations and street lights. The system generally consists of photovoltaic modules, solar controllers, inverters, batteries, loads, etc. The off-grid power generation system converts solar energy into electrical energy when there is light, supplies power to the load through the solar control inverter integrated machine, and charges the battery at the same time; when there is no light, the battery supplies power to the AC load through the inverter.
It is very practical for areas without power grid or areas with frequent power outages.
Hybrid energy storage system
Hybrid photovoltaic power generation systems are widely used in places where there are frequent power outages, or where photovoltaic power cannot be used for self-use, and the electricity price for self-use is much more expensive than the on-grid electricity price, and the peak electricity price is much more expensive than the trough electricity price.
The system consists of photovoltaic components, solar and hybrid inverter, battery, load, etc. The photovoltaic array converts solar energy into electrical energy when there is light, and supplies power to the load through the solar control inverter all-in-one machine, while charging the battery; when there is no light, the battery supplies power to the solar control inverter all-in-one machine, and then to the AC load power supply.
Compared with the On-grid power generation system, this system adds a charge and discharge controller and a battery. When the grid is out of power, the photovoltaic system can continue to work, and the inverter can switch to off-grid working mode to supply power to the load.