Photovoltaic (pv) grid photovoltaic power station and what is the difference between off-grid power station?

Off-grid pv power station is to take the solar power storage battery, and then through the inverter into household 220 v voltage. Photovoltaic (pv) grid power stations can probably understand, from the name it means with the mains connection, there is no electricity grid photovoltaic power station

off-grid photovoltaic power station will be solar energy stored in the battery, and then through the inverter converts it into household 220 v voltage. Photovoltaic (pv) grid power station can be roughly understand from its name. It refers to the grid photovoltaic power station connected with commercial power supply. Grid photovoltaic power station without energy storage device, through the inverter directly converted into voltage needed for the national grid. Family prefer using grid photovoltaic power station. Family to burn electricity can be sold to the country. At present, the national policy support and the support solar photovoltaic (pv) grid power generation. As long as the household photovoltaic (pv) grid power generation, they will receive state subsidies. However, if it is connected to the power grid, it must first apply to the local departments of the state grid. A grid photovoltaic power station, power grid connection means that it must be connected to the public grid, namely, solar power, family power and public power grid connected together. This is a must rely on the existing power grid operation of power systems. It is mainly composed of solar panels and inverter. Solar panels by 220 v ac inverter directly, for household appliances power supply. When the solar energy to produce electricity than household appliances use electricity, extra power is transmitted to the public grid. However, when the solar power can't meet the needs of household electrical appliances, it will be automatically added from the grid. The whole process of intelligent control, without manual operation. Because of the photovoltaic (pv) grid power station don't need battery, greatly saves the cost. In particular, the state issued new interconnection policy made clear that household photovoltaic power station can be connected to the electricity grid for free surplus power can also be sold to power company. From the perspective of long-term investment, based on the domestic photovoltaic power station the service life of 25 years, costs can be in the 4 - 6 years back, and the rest can earn 10 years or so. So, if you want to save electricity and power supply convenient, you should choose grid photovoltaic power generation system, which is the current mainstream way. Grid, however, also has its disadvantages, namely when the public power is cut off, photovoltaic (pv) grid power station can not run. However, if the grid inverter is intelligent network micro inverter ( Hybrid grid and off-grid inverter) Instead, power station can be run normally. The energy generated during the day, then, how to use the stored up for the night? It need to add the controller and battery. During the day, the controller will generate electrical energy stored in the storage battery, photovoltaic (pv) in the evening, the controller release of energy stored in the storage battery used for lighting. Second, off-grid photovoltaic power station which is also called independent photovoltaic power station. It is a independent of the power grid operation of power systems. It is mainly composed of solar panels, storage batteries, charge and discharge controller, inverter and other parts. Solar panels generate electricity directly into the battery and storage. When electrical need power supply, battery of direct current flows through the inverter, and converted into 220 v ac, this is a repeated charge and discharge cycle. Due to the power system is not subject to regional restriction, widely used and can only be installed in a sunny place to use, very suitable for no power grid, a lonely island, fishing boat, such as outdoor breeding base in remote areas. , also can be used as a frequent power outages areas of emergency power generation equipment.