scholarly journals A Compact and Fast Temperature-Response Heat Pump Water Heater

Author(s):  
B. J. Huang ◽  
F. H. Lin

A compact and fast temperature-response heat pump water heater was designed using multiple tanks and a sequential control device. The supply tank was heated as a priority by a freon-line switching device to increase the temperature recovery speed. A dual-tank prototype with 100-liter capacity was built and tested. The experimental results show that the time for temperature recovery of the supply tank from 42°C to 54°C reaches 10–20 minutes and COP reaches 2.0–3.0 during various seasons. The prototype tests show that an energy saving around 50%–70% as compared to the electrical water heater can be obtained. The hot water discharge efficiency of the heat pump is 0.912.

2016 ◽  
Author(s):  
Gabriel Agila ◽  
Guillermo Soriano

This research develops a detailed model for a Water to Water Heat Pump Water Heater (HPWH), operating for heating and cooling simultaneously, using two water storage tanks as thermal deposits. The primary function of the system is to produce useful heat for domestic hot water services according to the thermal requirements for an average household (two adults and one child) in the city of Quito, Ecuador. The purpose of the project is to analyze the technical and economic feasibility of implementing thermal storage and heat pump technology to provide efficient thermal services and reduce energy consumption; as well as environmental impacts associated with conventional systems for residential water heating. An energy simulation using TRNSYS 17 is carried to evaluate model operation for one year. The purpose of the simulation is to assess and quantifies the performance, energy consumption and potential savings of integrating heat pump systems with thermal energy storage technology, as well as determines the main parameter affecting the efficiency of the system. Finally, a comparative analysis based on annual energy consumption for different ways to produce hot water is conducted. Five alternatives were examined: (1) electric storage water heater; (2) gas fired water heater; (3) solar water heater; (4) air source heat pump water heater; and (5) a heat pump water heater integrated with thermal storage.


Author(s):  
Jielin Luo ◽  
Qin Wang ◽  
Zhen Zhao ◽  
Kaiyin Yang ◽  
Guangming Chen ◽  
...  

Abstract Considering the issues of environmental pollution and energy efficiency, heat pumps are gradually replacing traditional coal combustion for heating at low ambient temperatures. In this paper, eco-friendly CO2/HCs with large temperature glides are applied in a single-stage recuperative heat pump water heater. Its heating performance is theoretically investigated under the working condition of producing circulating hot water in typical winter of northern China, with medium temperature difference between supply/return water and large temperature difference between air inlet and water inlet. Due to its simple structure, low initial investment and high efficiency, its potential for producing circulating hot water is demonstrated. Exergy analyses are conducted to reveal the significant influence of the exergy losses of heat exchanger on system performance. For specified CO2/HC, optimal COP is obtained through global optimization of cycle pressures and mixture concentration. The heating performances of different CO2/HCs are compared, among which CO2/R600 and CO2/R600a behave better. Meanwhile, a typical vapor-injection cycle is used to demonstrate priorities on the heating performance of this recuperative cycle, in which the COP of recuperative cycle using CO2/R600 is more than 3.4% higher than that of the vapor-injection cycle. The results obtained in this paper provide a simple and efficient solution for producing circulating hot water at low ambient temperatures.


Author(s):  
Yahya I. Sharaf-Eldeen ◽  
Craig V. Muccio ◽  
Eric Gay

This work involves measurements, analyses, and evaluations of the performance of add-on, Heat Pump Water Heater (HPWH) systems in residential and small commercial applications. Two air-source Heat Pump (HP) systems rated at 7,000- and 12,000-BTU (2.051- and 3.517-kWh), were utilized in this work. The two HPs were retrofitted to two 50-gallon (189.3 liters) electric-resistance storage water-heaters with their electric heating elements removed. A third, standard electric water-heater (EWH), was used for comparison. The testing set-up was fully instrumented for measurements of pertinent parameters, including inlet and outlet water temperatures, inlet and outlet air temperatures of the HPs, temperature and humidity of the air in the surrounding space, volume of water draws out of the storage heater tanks, as well as electric energy consumptions of the systems. Several performance measures were used in this work, including the Coefficient of Performance (COP), which is a measure of the instantaneous energy output in comparison with the energy input; Energy Factor (EF), which is an average measure of the COP taken over extended periods of time; and the First Hour Rating (FHR), which is a measure of the maximum volume of hot water that a storage type water-heater can supply to a residence within an hour. The results obtained clearly indicate that, HPWH systems are much more efficient as compared to standard EWHs. While the average value of the EF for a standard EWH is close to 1.0, the HPWH systems yield EFs averaging more than 2.00, resulting in annual energy savings averaging more than 50%. The results also showed that, HPWH systems are effective at reducing utility peak demand-loads, in addition to providing substantial cost savings to consumers.


2021 ◽  
Author(s):  
Afarin Amirirad

Considering the large energy consumption of conventional water heaters in residential buildings, the performance of a new type of water heater has been characterized through conducting experiments and numerical modelling. The specific water heater investigated in this work benefits from heat absorption from the indoor air, denoted as the air source heat pump water heater (ASHPWH), and is located in the Archetype Sustainable Twin House B in Toronto. The experiments have been conducted under three different indoor conditions associated with temperature and humidity. The coefficient of performance (COP), which quantifies the ratio of heating capacity to the consumed power of ASHPWH, ranges between 1.5 and 5, depending on the indoor dry bulb and water inlet temperatures. A TRNSYS model of ASHPWH has been constructed based on the obtained experimental results and has subsequently been integrated with a TRNSYS model of the Archetype Sustainable House (ASH). The numerical results were verified with the experimental data. The model results suggests that after employing ASHPWH, the domestic hot water energy consumption reduces by 60.3% and 53.2% compared to the electric water heater in summer and winter respectively. Due to the energy absorption of ASHPWH from the indoor environment, the heating load of the ASH house increases while its cooling load decreases. Furthermore, the annual electricity consumption of the ASH house due to the required heating and cooling as well as the domestic hot water demand is reduced by 21.3%. Finally, as a consequence of employing ASHPWH, the energy cost and GHG emission were reduced respectively by 22% and 21.7%. By investigating the system in four other Canadian cities, it appears that Vancouver and Edmonton would have the maximum and minimum energy savings respectively.


2021 ◽  
Author(s):  
Afarin Amirirad

Considering the large energy consumption of conventional water heaters in residential buildings, the performance of a new type of water heater has been characterized through conducting experiments and numerical modelling. The specific water heater investigated in this work benefits from heat absorption from the indoor air, denoted as the air source heat pump water heater (ASHPWH), and is located in the Archetype Sustainable Twin House B in Toronto. The experiments have been conducted under three different indoor conditions associated with temperature and humidity. The coefficient of performance (COP), which quantifies the ratio of heating capacity to the consumed power of ASHPWH, ranges between 1.5 and 5, depending on the indoor dry bulb and water inlet temperatures. A TRNSYS model of ASHPWH has been constructed based on the obtained experimental results and has subsequently been integrated with a TRNSYS model of the Archetype Sustainable House (ASH). The numerical results were verified with the experimental data. The model results suggests that after employing ASHPWH, the domestic hot water energy consumption reduces by 60.3% and 53.2% compared to the electric water heater in summer and winter respectively. Due to the energy absorption of ASHPWH from the indoor environment, the heating load of the ASH house increases while its cooling load decreases. Furthermore, the annual electricity consumption of the ASH house due to the required heating and cooling as well as the domestic hot water demand is reduced by 21.3%. Finally, as a consequence of employing ASHPWH, the energy cost and GHG emission were reduced respectively by 22% and 21.7%. By investigating the system in four other Canadian cities, it appears that Vancouver and Edmonton would have the maximum and minimum energy savings respectively.


Author(s):  
H. I. Abu-Mulaweh

Heat pump water heater was designed and a prototype was developed and constructed. The performance of the heat pump water heater prototype is described by presenting some experimental test data. The experimental measurements include temperature, flow rates, and power consumption. The testing procedure consisted of evaluating the recovery rate and the coefficient of performance (COP) of the system. The results strongly indicate that heat pump water heater system design is very practical and it provides the consumer with a more efficient hot water heater alternative.


2015 ◽  
Vol 797 ◽  
pp. 185-191
Author(s):  
Arkadiusz Gużda ◽  
Norbert Szmolke

The article compares two means for domestic hot water production (DHW) for a detached house that is using gas boiler with a closed combustion chamber and air source heat pump water heater (ASHPWH). An analysis of domestic hot water production using an air source heat pump was made taking into account coefficient of performance listed according to the new BS EN 16147 standard. The analysis of outlay related to the investment and operating costs was also performed. Ultimately, the more profitable choice for domestic hot water production was made.


2010 ◽  
Vol 156-157 ◽  
pp. 1161-1164
Author(s):  
Ye Feng Liu ◽  
Guo Dong Gong ◽  
Xi Chen

The advantages of CO2 Heat Pump water heater include: CO2 is one of natural refrigerants and does not affect the global environment as many other HFCs refrigerants; CO2 heat pump water heater can produce hot water up to 90 ,which is higher than HFCs heat pump water heater(about 55 ).So the application of CO2 Heat Pump water heater is potential. But the Working pressure of CO2 Heat Pump Water Heater is about 9~12Mpa and is 3-5times of HFCs heat pump water heater’. Gas cooler is one of important part for CO2 heat pump water heater, and it must meet the needs of not only pressurization but also heat transfer. So it is important to design gas cooler correctly. In the paper, one system of CO2 Trans-critical Cycle Heat Pump Water Heater is designed, and double-pipe gas cooler is designed The heat transfer characteristics of CO2 in gas cooler with water in double-pipe heat exchanger was experimentally investigated. Experimental results showed that the gas cooler can meet the need of trans-critical CO2 cycle heat pump water heater. All the work is valuable for the application of CO2 heat pump water heater.


Author(s):  
Andriyan Andriyan ◽  
Urip Prayogi ◽  
Dwisetiono Dwisetiono

Kebutuhan air panas di kapal merupakan salah satu fasilitas yang harus didapatkan oleh ABK (Anak Buah Kapal) selama menjalankan tugasnya di kapal. KM. Meratus Karimata merupakan salah satu kapal yang menyediakan air panas sebagai fasilitas untuk ABK. Sistem pemanas pada kapal ini masih menggunakan sistem pemanas EHHW (Electric Heating Hot Water) yang kemudian akan dirubah dengan sistem HPWH (Heat Pump Water Heater). Kebutuhan air panas ini didasari oleh MLC (Marine Labour Convention) mengenai penyediaan recreational facilities pada akomodasi deck. Penyediaan air panas ini perlu dilakukan perhitungan dan perancangan, yang pertama dilakukan yaitu perhitungan seluruh komponen penunjang pendistribusian. Kemudian didapatkan data kebutuhan pompa dengan daya 0.504 Kw, valve, keran shower, keran wastafel, sambungan pipa, dan pipa SCH 40 dengan diameter ¾” dan 1”. Setelah itu dilakukan desain perancangan dengan menggunakan bantuan software. Setelah dilakukan perancangan, lalu dilakukan perhitungan biaya komponen dengan rincian harga valve Rp 10.129.000, pipa Rp 5.186.000, sambungan pipa Rp 1.751.000, pompa supplay Rp 1.150.000, HPWH 95.300.000. Harga dari EHHW dan HPWH ini terdapat selisih Rp 21.300.000 dimana lebih mahal HPWH. Tetapi dalam perhitungan konsumsi bahan bakar lebih hemat HPWH dengan data konsumsi bahan bakar HPWH 0,11 liter/jam dengan biaya Rp 1.249/jam, sedangkan konsumsi bahan bakar untuk EHHW 0,77 liter/jam dengan biaya Rp 10.116/jam.


Sign in / Sign up

Export Citation Format

Share Document