Sewage and rubbish stations: PV generation systems are usually used to supply the power. If the wind energy is available, the wind energy generation system or the solar wind hybrid system can also be joined. To turns down the
investment of electricity networks, the gird-off PV generation system, grid-off wind energy generation system or grid-off solar wind hybrid generation system should be selected as soon as possible. Only the scenic spots in cities should be taken the grid-connected generation system because there are more domestic sewage and more domestic garbage.