444
Y. Shimada et al.
Table 29.1 The
specifications of architecture
model and simulation cooling
load
Purpose of building
Supermarket
Building area (m 2 )
1600 (Square shape)
Number of floors
2
Total floor area (m 2 )
3200
Height of building (m)
14
U-Value (W/m 2 K) Outer wall
1.04
Ceiling
1.30
Roof
0.63
Floor
1.30
Cooling load
Maximum (kW) 426
Annual average
(kW)
231
Annual (MWh)
1180
29.3.2 System Designing and Electricity Consumption
In order to predict the energy consumption during the operation stage, the annual electricity consumption load was calculated per hour using the “GroundClub” simulation
software for GSHP (Nagano et al. 2006; Katsura et al. 2008).
An ASHP was selected as the comparison target, and its annual electricity
consumption load was calculated by “GroundClub”. Table 29.2 shows the specifications of GSHP and ASHP considered in this research.
The type of ground heat exchanger was the closed loop type with double U-tube.
The total length of ground heat exchanger (heat exchange well) was designed so that
the 90th percentile value of the heat pump inlet water temperature was 38 °C or less,
as that of atmospheric temperature was approximately 33 °C (Crawley et al. 2000).
This is based on the finding that the efficiency of a water source heat pump exceeds
that of an air source heat pump when the heat pump inlet water temperature exceeds
the atmospheric temperature by 5 °C (Yasukawa et al. 2009). The depth of each wells
was set at 50 m based on the geological survey (Yasukawa et al. 2009).
Table 29.2 The specifications of the GSHP and ASHP
Type of heat pump
GSHP
ASHP
Heat pump rated cooling COP
4.5
2.4
Calculated system COP
2.9
1.98
Type of ground heat exchanger
Double U-tube
–
Total length of the ground heat exchanger (m)
12,500
–
Subsurface temperature (°C)
28
–
Ground thermal conductivity (W/mK)
1.82
–
Ground heat capacity (kJ/m 3 K)
2600
–
Y. Shimada et al.
Table 29.1 The
specifications of architecture
model and simulation cooling
load
Purpose of building
Supermarket
Building area (m 2 )
1600 (Square shape)
Number of floors
2
Total floor area (m 2 )
3200
Height of building (m)
14
U-Value (W/m 2 K) Outer wall
1.04
Ceiling
1.30
Roof
0.63
Floor
1.30
Cooling load
Maximum (kW) 426
Annual average
(kW)
231
Annual (MWh)
1180
29.3.2 System Designing and Electricity Consumption
In order to predict the energy consumption during the operation stage, the annual electricity consumption load was calculated per hour using the “GroundClub” simulation
software for GSHP (Nagano et al. 2006; Katsura et al. 2008).
An ASHP was selected as the comparison target, and its annual electricity
consumption load was calculated by “GroundClub”. Table 29.2 shows the specifications of GSHP and ASHP considered in this research.
The type of ground heat exchanger was the closed loop type with double U-tube.
The total length of ground heat exchanger (heat exchange well) was designed so that
the 90th percentile value of the heat pump inlet water temperature was 38 °C or less,
as that of atmospheric temperature was approximately 33 °C (Crawley et al. 2000).
This is based on the finding that the efficiency of a water source heat pump exceeds
that of an air source heat pump when the heat pump inlet water temperature exceeds
the atmospheric temperature by 5 °C (Yasukawa et al. 2009). The depth of each wells
was set at 50 m based on the geological survey (Yasukawa et al. 2009).
Table 29.2 The specifications of the GSHP and ASHP
Type of heat pump
GSHP
ASHP
Heat pump rated cooling COP
4.5
2.4
Calculated system COP
2.9
1.98
Type of ground heat exchanger
Double U-tube
–
Total length of the ground heat exchanger (m)
12,500
–
Subsurface temperature (°C)
28
–
Ground thermal conductivity (W/mK)
1.82
–
Ground heat capacity (kJ/m 3 K)
2600
–