NOVELTY - The unit has solar power batteries (3) e.g. polysilicon solar power batteries, arranged on trestle decks (18), and a power feeding net (11) fixed with a high voltage transmission tower (12) via high voltage transmission wires (10). Salt resistance vegetables (14) transplanted from warm houses (13) are cultivated on a costal mudflat (16) i.e. bedstraw. The net transmits unwanted solar power sent by trestle solar power stations (17) to costal cities, and sends power for a plantation under a bridge when the warm houses, a lift pump (15) and lightening facilities (9) are in need of electricity.    USE - Power supply unit for a coastal mudflat trestle solar power station for a salt resistance vegetables plantation under a bridge in a costal city (all claimed).    ADVANTAGE - The unit enables solar power batteries to generate direct current by solar energy, and allows the direct current to be converted into low voltage alternating current after inputting in a photovoltaic interconnected inverter, and part of the low voltage alternating current is output from the power distribution part for supplying power to the warm house and the lift pump to cultivate salt resistance vegetables in the plantation under the bridge. The unit allows the remaining part of the low voltage alternating current to be inverted to high voltage alternating current and to be input in the power feeding net of the high voltage transmission tower.    DETAILED DESCRIPTION - The solar power batteries are selected from a group consisting of monocrystalline silicon solar power batteries, polysilicon solar power batteries, amorphous silicon film solar power batteries, polysilicon film solar power batteries, copper indium gallium compound film solar power batteries, organic solar power batteries, plastic solar power batteries, and sensitizing nano grain solar power batteries.    DESCRIPTION OF DRAWING(S) - The drawing shows a schematic view of a power supply unit.    Solar power batteries (3)    Lightening facilities (9)    High voltage transmission wires (10)    Power feeding net (11)    High voltage transmission tower (12)    Warm houses (13)    Salt resistance vegetables (14)    Lift pump (15)    Costal mudflat (16)    Trestle solar power stations (17)    Trestle decks (18)