The utility model discloses a temperature lowering pot for a heat energy utilization system. The side wall of one side of the temperature lowering pot is connected with a water inlet pipe of the temperature lowering pot and a back flushing water outlet pipe, and the side wall of the other side of the temperature lowering pot is connected with an overflow pipe; the bottom of the temperature lowering pot is connected with a blowdown pipe of the temperature lowering pot, the top of the temperature lowering pot is connected with a bleeder pipe, and a bleeder valve is arranged on the bleeder pipe; the side wall of the inner part of the temperature lowering pot is connected with a partition board; the connecting position of the overflow pipe and the temperature lowering pot is positioned on one side of the partition board, and the connecting position of the water inlet pipe of the temperature lowering pot and the temperature lowering pot and the connecting position of the back flushing water outlet pipe and the temperature lowering pot are positioned on the other side of the partition board. Through the adoption of the temperature lowering pot disclosed by the utility model, the lower temperature of back flushing water in a water softener can be used for lowering the temperature of waste water in the temperature lowering pot. The partition board and relevant structures can enable the waste water with relative high temperature in the temperature lowering pot not to overflow out of the temperature lowering pot immediately, instead, the waste water of which the temperature is naturally lowered on one side of overflowing is extruded out firstly, and the temperature of the waste water discharged out of the temperature lowering pot is further lowered.