29 Influence of Thermal Conductivity and Subsurface Temperature …
445
The rated coefficients of performance (COP) of GSHP and ASHP were determined using a technical data book of the manufacturer. Furthermore, the thermal
conductivity value was set at 1.82 W/m·K based on the result of the thermal response
test (TRT) conducted in Bangkok (Uchida and Fujii 2018). The subsurface temperature was set at 28 °C based on the hearing investigation to the pilot study research
group (Chokchai et al. 2018).
According to the simulation, the annual electricity consumption load of GSHP
was approximately 400 MWh, while that of ASHP was approximately 600 MWh.
Therefore, the annual electricity consumption load of GSHP was 33% lower than
that of ASHP.
29.3.3 Life-Cycle Inventory Analysis
Life-cycle inventory analysis was conducted following the guidelines for the lifecycle assessment of GSHP (Ministry of the Environment, Japan 2012).
The functional unit was set as one-year’s operation of heat pump on the
architecture model which was designed at the “3.1 simulation of cooling load”.
The system boundary was set as the entire life-cycle, from the manufacturing to
the disposal stages. Figure 29.1 shows the system boundary of life-cycle inventory
analysis. The installation stage of ASHP did not include the construction material
manufacturing, waste transportation, and waste intermediate treatment processes,
since those processes were assumed to be occurred during the construction of ground
heat exchanger.
The lifetime of ground heat exchanger was set at 50 years, and that of other
equipment was set at 20 years. The operation period of GSHP was set at 50 years
in accordance with the lifetime of ground heat exchanger. On the other hand, the
operation period of ASHP was set at 20 years.
The process data list which are required for the analysis were determined by
following the guidelines (Ministry of the Environment, Japan 2012). The process
data list and data source are shown in Table 29.3. Each process data was set as the
amount of one-year in accordance with the functional unit. All equipment materials
were the latest models as of 2017, and it was assumed that those manufactured in
Japan were used in Thailand.
IDEA v2 (National Institute of Advanced Industrial Science and Technology,
Japan Environmental Management Association for Industry 2017), inventory
database for LCA in Japan, which was replaced with the power supply configuration
in Thailand, was used for background data.
Lastly, LC–CO 2 , LC–NO X , and LC–SO 2 were obtained from multiplying the
process and foreground data.
445
The rated coefficients of performance (COP) of GSHP and ASHP were determined using a technical data book of the manufacturer. Furthermore, the thermal
conductivity value was set at 1.82 W/m·K based on the result of the thermal response
test (TRT) conducted in Bangkok (Uchida and Fujii 2018). The subsurface temperature was set at 28 °C based on the hearing investigation to the pilot study research
group (Chokchai et al. 2018).
According to the simulation, the annual electricity consumption load of GSHP
was approximately 400 MWh, while that of ASHP was approximately 600 MWh.
Therefore, the annual electricity consumption load of GSHP was 33% lower than
that of ASHP.
29.3.3 Life-Cycle Inventory Analysis
Life-cycle inventory analysis was conducted following the guidelines for the lifecycle assessment of GSHP (Ministry of the Environment, Japan 2012).
The functional unit was set as one-year’s operation of heat pump on the
architecture model which was designed at the “3.1 simulation of cooling load”.
The system boundary was set as the entire life-cycle, from the manufacturing to
the disposal stages. Figure 29.1 shows the system boundary of life-cycle inventory
analysis. The installation stage of ASHP did not include the construction material
manufacturing, waste transportation, and waste intermediate treatment processes,
since those processes were assumed to be occurred during the construction of ground
heat exchanger.
The lifetime of ground heat exchanger was set at 50 years, and that of other
equipment was set at 20 years. The operation period of GSHP was set at 50 years
in accordance with the lifetime of ground heat exchanger. On the other hand, the
operation period of ASHP was set at 20 years.
The process data list which are required for the analysis were determined by
following the guidelines (Ministry of the Environment, Japan 2012). The process
data list and data source are shown in Table 29.3. Each process data was set as the
amount of one-year in accordance with the functional unit. All equipment materials
were the latest models as of 2017, and it was assumed that those manufactured in
Japan were used in Thailand.
IDEA v2 (National Institute of Advanced Industrial Science and Technology,
Japan Environmental Management Association for Industry 2017), inventory
database for LCA in Japan, which was replaced with the power supply configuration
in Thailand, was used for background data.
Lastly, LC–CO 2 , LC–NO X , and LC–SO 2 were obtained from multiplying the
process and foreground data.