37 Evaluation and Improvement Proposals for a Business Facility …
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Fig. 37.7 Energy utilization rate of each energy and the whole system
37.3.4 Performance Evaluation of the Entire System
In Fig. 37.7 we show the calculation method of the energy utilization rate and we
present the energy utilization rate of the whole system by month. The formula for
calculating energy efficiency is shown in Eq. 37.2. The result showed that the energy
utilization factor in summer is low, and it can be observed that the amount of heat
extraction from the ground heat is largest. This is considered to be due to the decrease
in the COP of the geothermal heat pump in addition to the increase in the power
consumption.
E =
P
P c + Q
(37.2)
E: Energy utilization rate [%]
P: Output [MJ]
P c: Power consumption [MJ]
Q: Heat input [MJ]
37.4 System Improvement Proposal
37.4.1 Factor Analysis of Air Conditioning Malfunction
of Store C
In the summer of 2018, the air conditioning system malfunctioned in store C. Furthermore, the store’s thermal environment could not be maintained. At the same time,
the temperature in Honjo City at that time has exceeded 40 °C. The geothermal