System design and case study of graded heating by groundsource water

To fully use the high temperature groundsource water and the nonuniform indoor thermal environment, proposes a graded heating system utilizing groundsource water. Part of the groundsource water is directly used to heat the building envelope while the other part is used by heat pump to deal with the residual heating load. Selects a building with typical glass curtain wall in Beijing, with groundsource heat pump as an example, constructs the heat transfer numerical calculation model and calculation method of energy consumption and analyses the hourly system performance in the whole heating season. The results show that the graded heating system can increase the window temperature about 2.3 ℃ and reduce 16.8% of the cumulative heating load and 33.1% of the peak heating load. The energysaving rate is as high as 13.0% because of the direct use of groundsource water without energy consumption. The initial cost will not be increased while the operation cost can be saved. The performance would be even better if the ambient temperature is lower.