Optimal Supply Water Temperature Control of Water Source Heat Pump

Solar Energy ◽  
2005 ◽  
Author(s):  
M. Palahanska-Mavrov ◽  
G. Wang ◽  
M. Liu
Keyword(s):  
Potential Energy ◽  
Water Temperature ◽  
Heat Pump ◽  
Temperature Control ◽  
Energy Cost ◽  
Energy Savings ◽  
Water Source ◽  
Theoretical Models ◽  
The Impact ◽  
Supply Water

The water loop supply water temperature is the most critical control parameter for operating energy cost in water source heat pump systems. In this paper, the impact of the water loop temperature on operating energy cost is investigated for different types of buildings under different loads using theoretical models. The theoretical models and approaches are also applied to an 80,000 square feet office building to determine the building heating and cooling load, optimal supply water temperature, and potential energy cost savings based on measured supply water temperature and loop heat gain. It is concluded that the optimal supply water temperature control can significantly reduce the annual energy costs associated with compressor power and boiler energy. The potential energy savings is determined to be 24% in the application building.

Energy Analysis and Optimization of a Water-Loop Heat Pump System

2010 ◽  
Vol 2 (2) ◽  
Author(s):  
Shui Yuan ◽  
Michel Grabon
Keyword(s):  
Water Temperature ◽  
Heat Pump ◽  
Energy Savings ◽  
Water Source ◽  
Energy Performance ◽  
Heat Pumps ◽  
Pump System ◽  
Heat Pump System ◽  
Heating And Cooling ◽  
The Impact

A water-loop heat pump system consists of a set of water-source heat pumps that are connected with a closed-loop water network, which allows heat to be injected into or extracted out of the loop water. Such a configuration is able to meet simultaneous heating and cooling demands with a heat recovery capability. This paper analyzes the impact of loop water temperature on energy performance of individual heat pumps and the whole system, demonstrates that there exists a unique loop water temperature that minimizes overall power consumption of the configuration under discussion, and proposes a strategy to find the optimal temperature, which can be implemented in a real-time application. Simulations have been conducted to verify that a significant energy savings can be achieved over conventional practice.

scholarly journals Characterization of Wrapped Coil Tank Water Heater During Charging/Discharging

2017 ◽  
Author(s):  
Ahmed Elatar ◽  
Kashif Nawaz ◽  
Bo Shen ◽  
Van Baxter ◽  
Omar Abdelaziz
Keyword(s):  
Water Temperature ◽  
Heat Pump ◽  
Thermal Stratification ◽  
Water Tank ◽  
Water Heater ◽  
Water Heaters ◽  
Discharge Flow Rate ◽  
Circulation Patterns ◽  
The Impact ◽  
Supply Water

Heat pump water heaters (HPWH) are an energy efficient method for water heating compared to conventional electric water heaters. A wrapped coil around the water tank is often used as the condenser for the heat pump for such applications. Thermal stratification, caused by varying heat transfer rate from the condenser to the water depending on the phase of the refrigerant and the wrap configuration, is often observed inside the tank, especially for HPWHs using CO2 as the refrigerant. The current study investigates the impact of the charging/discharging process on thermal stratification. A series of simulations were conducted based on the draw patterns recommended by the DOE method of test for rating water heater performance. We also analyzed the water circulation patterns during charging/discharging process. The thermal stratification was adversely affected because of the circulation even when the Heat Pump (HP) was operational. It was observed that a relatively higher charge/discharge flow rate disrupts the thermal stratification quickly and thus lowers the supply water temperature. Furthermore, the duration of charging/discharging also plays an important role. It was noticed that the back flow has insignificant effect on the supply water temperature if charging/discharging time is relatively small. However, the effect was obvious for larger water draw flow rates that last for longer time.

scholarly journals Energy Conservation Potential of Economizer Controls Using Optimal Outdoor Air Fraction Based on Field Study

Energies ◽  
2020 ◽  
Vol 13 (19) ◽  
pp. 5038
Author(s):  
Goopyo Hong ◽  
Chul Kim ◽  
Jun Hong
Keyword(s):  
Energy Consumption ◽  
Energy Conservation ◽  
Temperature Control ◽  
Energy Savings ◽  
Cooling System ◽  
Energy Performance ◽  
Outdoor Air ◽  
Humid Climate ◽  
Differential Enthalpy ◽  
The Impact

In commercial buildings, HVAC systems are becoming a primary driver of energy consumption, which already account for 45% of the total building energy consumption. In the previous literature, researchers have studied several energy conservation measures to reduce HVAC system energy consumption. One of the effective ways is an economizer in air-handling units. Therefore, this study quantified the impact of the outdoor air fraction by economizer control type in cooling system loads based on actual air-handling unit operation data in a hospital. The optimal outdoor air fraction and energy performance for economizer control types were calculated and analyzed. The result showed that economizer controls using optimal outdoor air fraction were up to 45% more efficient in cooling loads than existing HVAC operations in the hospital. The energy savings potential was 6–14% of the differential dry-bulb temperature control, 17–27% of the differential enthalpy control, 8–17% of the differential dry-bulb temperature and high-limit differential enthalpy control, and 16–27% of the differential enthalpy and high-limit differential dry-bulb temperature control compared to the no economizer control. The result of this study will contribute to providing a better understanding of economizer controls in the hospital when the building operates in hot-humid climate regions.

The Combined Solar with a Dual Heat Source Heat Pump Applied in a Greenhouse Heating System - An Operation Optimization of Water Source Heat Pump

2014 ◽  
Vol 541-542 ◽  
pp. 942-948
Author(s):  
Xian Peng Sun ◽  
Zhi Rong Zou ◽  
Yue Zhang
Keyword(s):  
Heat Source ◽  
Heat Pump ◽  
Water Source ◽  
Heating System ◽  
Hot Water ◽  
Inlet Temperature ◽  
Pump System ◽  
Operation Optimization ◽  
Temperature Heat ◽  
The Impact

Based on the finite-time thermodynamic theory, an operation optimization, of water source heat pump in the combined solar with a dual heat source heat pump which is applied in a greenhouse heating system, is made. According to the ε-NTU method and entropy theory, heat exchange and balance equations are obtained. The function relationship between COP and the indoor temperature Tn, the ambient temperature Ta, low temperature heat source inlet temperature Tie and high temperature heat source inlet temperature Tic is also obtained. By means of programming, the impact of parameters on the COP and the way of regulating this water source heat pump system are presented in this article. The results show that: when a separate water source heat pump is running, by adjusting the hot water temperature and the match status of each indoor heating system, the energy-saving operation can be realized.

scholarly journals Evaluation of the potential energy savings of a centralized booster heat pump in front of conventional alternatives

Smart Energy ◽  
2021 ◽  
pp. 100056
Author(s):  
X. Masip ◽  
Carlos Prades-Gil ◽  
Emilio Navarro-Peris ◽  
J.M. Corberán
Keyword(s):  
Potential Energy ◽  
Heat Pump ◽  
Energy Savings

scholarly journals Impact of Carbon Pricing on Energy Cost Savings Resulting from Installation of Gas-Fired Absorption Heat Pump at A Library Building in Ontario

Proceedings ◽  
2019 ◽  
Vol 23 (1) ◽  
pp. 2 ◽  
Author(s):  
Altamash Ahmad Baig ◽  
Alan S. Fung
Keyword(s):  
Natural Gas ◽  
Heat Pump ◽  
Energy Cost ◽  
Energy Savings ◽  
Cost Savings ◽  
Conventional Heating ◽  
Positive Energy ◽  
Cooling Mode ◽  
Carbon Pricing ◽  
Absorption Heat Pump

This paper presents the results of analyzing the potential benefits of a natural gas-fired absorption heat pump (GAHP) for a library building in Ontario in terms of energy savings, fuel cost savings, and reduction in greenhouse gas emissions. Simulation model for the library building was created in eQUEST and calibrated using the energy consumption data from the 2012–2014. The results for energy savings were analyzed to include the effect of implementation of carbon pricing. It was concluded that because of implementation of carbon pricing, the replacement of conventional heating equipment with more efficient gas-fired heat pump would increase the monetary value of the savings achieved from reduced natural gas consumption, due to increased price of natural gas. Furthermore, due to the longer heating season in Canada and the relatively higher price of electricity compared to natural gas the gas-fired heat pump can potentially achieve positive energy cost savings when operated in both heating and cooling mode even after implementation of carbon pricing.

Performance and Benefits Evaluation of Two Water-Source Heat Pump Systems for District Heating

2012 ◽  
Vol 204-208 ◽  
pp. 4225-4228
Author(s):  
Xiao Chen ◽  
Jie Han ◽  
Jing Zeng
Keyword(s):  
Heat Pump ◽  
System Performance ◽  
Energy Savings ◽  
District Heating ◽  
Water Source ◽  
Primary Energy ◽  
Test Results ◽  
Actual Performance ◽  
Heating Source ◽  
Groundwater Heat Pump

The heating source of a district heating (DH) system in Beijing was reformed from coal boilers to a groundwater heat pump (GWHP) system and a sewage source heat pump (SSHP) system. This study aims to evaluate the actual performance and benefits of two water-source heat pump systems. We found total energy savings and primary energy saving rate due to the retrofit to be 950 tons of standard coal equivalent (TCE) every year and 34.6%, respectively. Field test results indicated the necessity of system performance improvement. Appropriate approaches to improve the system performance were discussed.

DESIGN OF AN EMBEDDED SYSTEM FOR WATER TEMPERATURE CONTROL IN A SOLAR ASSISTED HEAT PUMP

2017 ◽  
Author(s):  
Tiago de Freitas Paulino ◽  
Euler Fonseca ◽  
Antônio Maia ◽  
Luiz Machado ◽  
Ricardo Koury
Keyword(s):  
Embedded System ◽  
Water Temperature ◽  
Heat Pump ◽  
Temperature Control
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