The invention discloses a summer and winter cold and
hot water supply method for a cultivation farm. In winter, firstly, acquired
seawater and
fresh water pumped from a
fresh water well are mixed into mixed water; and secondly, after heat exchange, mixed water flows into condensers of two single-screw
water source heat pump units in parallel and is turned into cultivation hot water after absorbing heat, after waste water formed by high-temperature water after heat exchange is mixed with
fresh water pumped from the fresh
water well, mixture of the waste water and the fresh water flows into a
heat exchanger to indirectly exchange heat with water on
evaporator sides of the two
heat pump units, and circulating water in independent water systems of the
evaporator sides flows into evaporators of the
heat pump units in parallel after heat exchange to
discharge heat. In summer, acquired
seawater is mixed with fresh water pumped from the fresh
water well, and then flows into the evaporators of the two heat pump units in parallel, and required cultivation cold water can be obtained after mixture of the
seawater and the fresh water realizes heat
discharge and is cooled; and a second channel of seawater directly flows into the condensers of the two heat pump units in parallel after being pressurized by a cooling water circulating water pump, and is drained after heat is absorbed. The method is efficient and energy-saving and is low in running expense.