Household solar power generation systems are divided into off-grid and grid-connected systems:
1. Off-grid power generation system. It is mainly composed of solar cell module, controller and battery, and ac inverter is needed to supply power for AC load. Batteries can be charged from solar panels to power household loads in dark and rainy weather.
2. Grid-connected power generation system means that the direct current generated by solar modules is converted into alternating current conforming to the requirements of the municipal power grid by the grid-connected inverter, and then directly connected to the public power grid. There are centralized large-scale grid-connected power stations in the grid-connected power system, which are generally large power stations. The main feature is that the generated power can be directly transmitted to the power grid, and the power supply can be uniformly distributed to users by the grid. However, this kind of power station is relatively difficult to develop because of its large investment, long construction period and large floor space. The distributed small-scale grid-connected power generation system, especially the integrated photovoltaic building power generation system, is the mainstream of grid-connected power generation due to its advantages such as small investment, fast construction, small floor space and great policy support.