Solar photovoltaic energy storage

In different application scenarios in life, solar power generation and energy storage systems include grid-connected energy storage systems, off-grid energy storage systems, grid-connected and off-grid energy storage systems, and multi-energy hybrid microgrid energy storage systems.
Grid-connected energy storage can increase the occupancy rate of self-generation and self-use by storing excess power generation. It is mostly suitable for scenarios such as self-use electricity is much more expensive than grid-connected electricity, peak electricity prices are much more expensive than flat electricity prices, and system power generation surplus. The entire system consists of grid-connected arrays, grid-connected inverters, battery packs, loads, etc. Some places have installed photovoltaic systems before, and subsidies have been cancelled after policy changes. You can try to install a grid-connected energy storage system for self-sufficiency. The grid-connected energy storage machine is compatible with inverters of different brands. The original photovoltaic system can remain unchanged. When it starts working, it will store excess power generation in the battery, and when the load increases at night, the battery will be used to supply power to the load through the inverter.
Off-grid energy storage systems operate independently and do not rely on the power grid. They are mostly suitable for remote areas, islands, base stations, etc. For use in areas without power grids and frequent power outages, off-grid systems tend to be more like "sending charcoal in the snow". They are composed of photovoltaic arrays, battery packs, inverters, etc. When there is light, it supplies power to the load while charging the battery pack. When there is no light, the battery pack in turn supplies power to the AC load through the inverter, which has strong practical value. At present, the cost of generating one kilowatt-hour of electricity off-grid is much higher than that of grid-connected electricity, but it is nearly half cheaper than diesel power generation.
Off-grid energy storage is mostly suitable for self-sufficiency with surplus, self-use electricity is much more expensive than grid-connected electricity, etc. It is composed of photovoltaic arrays, off-grid integrated machines, loads, etc. Compared with grid-connected, it adds some costs but has a wider range of applications. It can earn the difference by charging in the valley period of electricity prices and discharging in the peak period, or it can reduce expenses by outputting at rated power at the peak of electricity prices, and even switch to off-grid mode as a backup power source to supply power to the load through the inverter during a power outage.
Finally, multi-energy storage can effectively tap into the potential of clean energy and ensure the safety of the power grid by reducing unfavorable factors such as unstable power generation. It is composed of solar arrays, bidirectional converters, generators, etc., which can supply power to the load and charge the storage group when there is sunlight, and supply power to the load through a bidirectional AC when there is no sunlight. The scale of the microgrid system is particularly flexible, ranging from several gigawatts to tens of megawatts, and is flexible and widely used.