Model development and numerical analysis of a vertical falling film absorption heat pump

Performance analysis and optimization for a novel air-source gas-fired absorption heat pump

Performance analysis on compression-assisted absorption heat transformer: A new low-temperature heating system with higher heating capacity under lower ambient temperature

A solar-air source heat pump with thermosiphon to efficiently utilize solar energy

TRNSYS simulation software was used to modify a validated Air Source Heat Pump (ASHP) model in an Archetype Sustainable House (ASH) in Toronto. In this model, a Building Integrated Photovoltaic-Thermal Collector (BIPV/T) was coupled with ASHP. The PV/T system arrangement was considered as a part of the south-oriented roof of the house. The warm air generated in the BIPV/T collector was considered the source of the heat pump for heat production. The coupling of BIPV/T and ASHP enables a highly efficient heating system in harsh winter conditions. The developed TRNSYS model of the house along with integrated PV/T system with ASHP was simulated for the whole year to predict the hourly outlet air temperature, thermal energy and electricity obtained from the PV/T array. The results from the simulation were used to estimate the saving in energy and cost as well as to predict the electricity related GHG emission reduction potential from the PV panels. Monthly greenhouse gas (GHG) emission credit from PV production based on hourly GHG emission factor was obtained; the results showed that annual GHG emission due to electricity demand by the ASHP was reduced by 225 kg CO2 (19.3%) when the heat pump was integrated with the PV/T array. Also, in this study, the annual electricity cost credit from PV production based on Time-of-Use (TOU) and the reduction in electricity cost of the heat pump when connected with PV/T systems was calculated and compared with the cost of working the heat pump alone. The results show that there is a saving of $500 in annual electricity bills and GHG emission credit of 862.6 kg CO2 from renewable electricity generation.

Feasibility Analysis of Building Heating System Based on Thermal-Economical Evaluation

Research and application of park multi-source synergistic and complementary heating system and its coordinated control method

Long-term energy and exergy analysis of heat pumps with different types of ground and air heat exchangers

On the value of combined heat and power (CHP) systems and heat pumps in centralised and distributed heating systems: Lessons from multi-fidelity modelling approaches

The impact of climate change on air source heat pumps

Heating performance of a vapor compression heat pump cascaded with a thermoelectric heat pump

Heat pump systems are promising technologies for current and future buildings and this research presents the performance of air source heat pump (ASHP) system. The system was monitored, analysed and simulated using TRNSYS software. The experimental data were used to calibrate the simulation model of ASHP. The specific climate conditions are evaluated in the model. It was noticed for the heating mode that the coefficient of performance (COP) varied from 1.98 to 3.05 as the outdoor temperature changed from –7.0 ºC to +5.0 ºC, respectively. TRNSYS simulations were also performed to predict seasonal performance factor of the ASHP for Vilnius city. It was identified that seasonal performance prediction could be approximately 15% lower if frost formation effects are not included to air-water heat pump simulation model.

In South Africa, there is an ongoing constraint on the electricity supply at the national grid to meet the demand. Eskom is implementing various measures such as the Integrated Demand Management and the promotion and encouragement of the use of energy efficient devices like an Air Source Heat pump (ASHP) water heater to replace the high electrical energy consuming conventional geysers for sanitary hot water production. The ASHP water heater market is fast gaining maturity. A critical mathematical model can lead to performance optimization of the systems that will further result in the conservation of energy and significant reduction in global warming potential. The ASHP water heater comprises of an ASHP unit and a hot water storage tank. In this study, a data acquisition system (DAS) was designed and built which monitored the energy used by the geyser and the whole building, the temperature at the evaporator, condenser, tank outlet hot water, tank inlet cold water, the ambient temperature and relative humidity in the vicinity of the ASHP evaporator. It is also worthy to mention that the DAS also included to a flow meter and two additional temperature sensors that measured the volume of water heated and inlet and outlet water temperature of the ASHP. This work focused on using the mathematical equation for the Coefficient of Performance (COP) of an ideal Carnot’s heat pump (CHP) water heater to develop basic computation in M-file of MATLAB software in order to model the system based on two reservoir temperatures: evaporator temperatures (Tevp) of 0°C to 40°C (approximated to ambient temperature, Ta) and condenser temperatures (TCon) set at 50°C, 55°C and 60°C (approximated to the hot water set temperature of 50°C, 55°C and 60°C) respectively. Finally, an analytical comparison of a CHP water heater to the practical ASHP water heater was conducted on a hot water set point temperature of 55°C. From the modelling results, it can be deduced that at 0°C Tevp, the COP was 5.96 and 2.63 for CHP and ASHP water heater respectively, at a hot water set temperature of 55°C. Above 20°C Tevp, the rate of change of COP increased exponentially for the ideal CHP system, but was constant at 0.01/°C for the practically modelled ASHP water heater.

The demand for air conditioning in Southeast Asia has increased in recent years owing to rapid economic growth in the region. On the other hand, power generation still relies on fossil fuels. A ground source heat pump (GSHP) is an alternative to reducing the energy required for cooling and heating in many countries. The use of a GSHP in a tropical climate like Southeast Asia is mainly for cooling (i.e., heat rejection), and the temperature differences between soil background and atmosphere are low throughout the year. This paper addresses the potential use of GSHP in Southeast Asia based on short-term performance data. Four GSHP systems have been installed in Thailand and Vietnam. Data gathered from the short-term operations provides important insights on GSHP performance. A comparison with an air source heat pump (ASHP) indicates that a GSHP installed at the Bangkok, using two vertical ground heat exchangers (GHEs), achieves a maximum of 33% electricity reduction. Similarly, GSHPs installed at the Saraburi site using horizontal GHEs achieves a maximum of 18.5% and 40.3% less electricity during highest and lowest temperature seasons, respectively, compared with an ASHP. The results also show that parallel–series arrangement improves the thermal performance than those of series–parallel arrangements. Considering the wide temperature climate range of Hanoi, a GSHP can also be used for heating purposes during a short winter period. While the short-term results discussed in this paper suggest the potential use of GSHP in Southeast Asia, further long-term analysis, cost evaluations and system optimization are required.

With the establishment of 3060 double carbon target, higher requirements are put forward for clean energy heating of new buildings in China. Among them, air source heat pump has entered the public’s field of vision with its characteristics of cleanness, environmental protection and high operating efficiency. With the development of heat pump technology, air-source heat pump can run stably at -25°C, and Zhangjiakou, which is located in a cold area, can also use air-source heat pump as the heat source of office buildings. At the same time, the economic analysis shows that the building heating cost of air source heat pump heating system is more economical and energy-saving than that of new central heating system.

Renewable energy systems have received considerable attention as a sustainable technology in the building sector. Specifically, the use of ground-source heat pump (GSHP) and air-source heat pump (ASHP) for heating and cooling of buildings is increasing rapidly, and the combination with photovoltaic (PV) systems and heat pump systems provide energy savings and environmental benefits. This study investigates the feasibility of replacing conventional heating and cooling systems in a multifamily, residential building with GSHP and ASHP systems and their combination with PV. The integration of PV with GSHP and ASHP systems presents an opportunity for increased solar energy usage resulting in a reduction of electricity demanded and a reduction of emissions of greenhouse gases. To analyze different heat pumps systems with and without PV, system modeling and computer simulations are performed with RETScreen Expert software.A multifaceted verification and validation study is conducted for the system model and computer simulation. The important objective of this part of the study is to understand and develop confidence for modelling individual studies in RETScreen Expert software. To accomplish this, RETScreen Expert is used for modeling and simulating the performance of PV systems in several geographical locations, including Fort Wayne, IN. A comparison is made to performance predictions from System Advisory Model (SAM) software. In addition, a study is done to compare predictions from both software to previously published data.In the further phase of the study, eQUEST software, a tool for building energy simulation is used to predict outputs such as electricity consumption, heating loads, and cooling loads for the multifamily residential building considered in this study. These outputs, as well as, building parameters are used as inputs to RETScreen Expert. Since, this study focuses on modeling and simulating the heating and cooling systems coupled with PV for feasibility analysis, only a few minor modifications to the eQUEST default settings are made.The outputs from eQUEST are used as inputs to RETScreen Expert and analysis of ASHP and GSHP systems, as well as their combination with a PV system are performed. The results include the technical performance and financial model of each system, which can be used to indicate feasibility. The results show that both GSHP and ASHP systems are environmentally friendly and reduce energy consumption. These systems are economically feasible, with payback periods of under 10 years, when electricity prices are high. When combined technology is preferred, PV-GSHP systems are more environmentally friendly and have fuel savings far better than any other proposed systems. But the feasibility of the both the GSHP and PV-GSHP systems strongly depends on loop installation cost.