1. Independent photovoltaic power generation
Independent photovoltaic power generation is also called off-grid photovoltaic power generation. It is mainly composed of a solar cell module, a controller, and a battery. To supply power to an AC load, an AC inverter needs to be configured. Independent photovoltaic power plants include village power supply systems in remote areas, solar household power systems, communication signal power supplies, cathodic protection, solar street lights, and other photovoltaic power generation systems with independent operation.
2. Grid-connected photovoltaic power generation
Grid-connected photovoltaic power generation is the direct current access to the public power grid after the DC power generated by the solar modules is converted into AC power that meets the requirements of the mains grid. It can be divided into grid-connected power generation systems with and without batteries.
The grid-connected power generation system with battery has schedulability, can be merged into or out of the grid as needed, and has the function of standby power supply, which can be powered urgently when the power grid is powered off. Photovoltaic grid-connected power generation systems with batteries are often installed in residential buildings; grid-connected power generation systems without batteries do not have the functions of schedulability and backup power, and are generally installed on larger systems.
Grid-connected photovoltaic power generation has centralized large-scale grid-connected photovoltaic power plants, which are generally state-level power stations. The main feature is that the power generation can be directly delivered to the power grid, and the power grid can be uniformly deployed to supply power to users. However, this kind of power station has a large investment, a long construction period and a large area, and it has not developed much. Decentralized small-scale grid-connected photovoltaics, especially photovoltaic building integrated photovoltaic power generation, is the mainstream of grid-connected photovoltaic power generation due to its advantages of small investment, fast construction, small floor space and strong policy support.
3. Distributed photovoltaic power generation
Distributed photovoltaic power generation system, also known as decentralized power generation or distributed power supply, refers to the configuration of a small photovoltaic power generation system at or near the user site to meet the needs of specific users and support the economy of existing distribution networks. Run, or both, meet both requirements.
The basic equipment of the distributed photovoltaic power generation system includes photovoltaic cell components, photovoltaic array brackets, DC combiner boxes, DC power distribution cabinets, grid-connected inverters, AC power distribution cabinets, etc. In addition, power supply system monitoring devices and environmental monitoring Device. The operation mode is that under the condition of solar radiation, the solar cell module array of the photovoltaic power generation system converts the electric energy converted by the solar energy into the DC power distribution cabinet through the DC combiner box, and is converted into the AC power supply by the grid-connected inverter. The building’s own load, excess or insufficient power is regulated by connecting the grid.
The state has considerable attention to photovoltaic power generation. At present, there is a new change in the on-grid price of photovoltaic power generation benchmarks. The on-grid tariff of PV power plants put into operation after January 1, 2018 is reduced, and Class I, Class II and Class III resource areas are reduced. The benchmark on-grid price is adjusted to 0.55 yuan, 0.65 yuan, and 0.75 yuan per kWh (including tax). At the same time, for distributed photovoltaic projects that have been put into operation after January 1 and adopt the “spontaneous use and surplus online” mode, the subsidy for electricity is reduced to 0.37 yuan per kWh (including tax), only the village level with poverty alleviation. The subsidies for photovoltaic poverty alleviation power stations (0.5 MW and below) and household distributed photovoltaic poverty alleviation projects remain unchanged.