A LITERATURE REVIEW ON LOW QUALITY WASTE HEAT … · 2018-12-22 · Heat recovery heat pumps have been designed to recover condenser waste heat by using water-cooled condensers to

A LITERATURE REVIEW ON LOW–QUALITY WASTE HEAT RECOVERY IN

RESIDENTIAL AND COMMERCIAL SETTINGS

BY

EMMANUEL OMERE

THESIS

Submitted in partial fulfillment of the requirements

for the degree of Master of Science in Mechanical Engineering

in the Graduate College of the

University of Illinois at Urbana-Champaign, 2016

Urbana, Illinois

Adviser:

Professor Anthony Jacobi

ii

Abstract

Increasing demand for energy saving technologies has led to substantial interest in

waste heat recovery systems. This interest is reflected in rapid growth in the rate of

publication of related technical articles. The purpose of this literature review is to

evaluate proposed low quality waste heat recovery systems in residential and commercial

settings. The basics and limitations of these systems are outlined with attention directed

towards identifying new systems with promise.

iii

Table of Contents

Introduction.……………………………………………………………………………... 1

Definition of Concept.…………………………………………………………………… 2

Conventional Heat Exchanger Heat Recovery.………………………..………………… 2

Novel Heat Exchanger Heat Recovery…………………...……………………………… 3

Conventional Heat Pump Heat Recovery.……………………………..………………… 6

Novel Heat Pump Heat Recovery…………………...………………...………………… 7

Conventional Hybrid Heat Recovery.………………………..…………………………. 16

Novel Hybrid Heat Recovery…………………...………………………………………. 16

Conclusions.…………………………………………………………………………….. 19

References...…………………………………………………………………………….. 21

1

Introduction

Economic growth has led to expansion of building sectors, increasing building

energy consumption in the process. About 48% of consumable energy was utilized by the

residential and commercial sector of the U.S. in 2014 [29]. Most of this energy is used for

space heating, water heating, and air conditioning. In 2009, The U.S. Energy Information

Administration stated that these needs consume 65% of energy use in residences [30].

The remaining 35% was expended by appliances, electronics, and lighting. Increased

energy costs and concerns with environmental impacts drive continued efforts to improve

end-use energy efficiency. Waste heat recovery may be an important part of these efforts

to reduce primary energy consumption. However, the initial cost of heat recovery

systems, skilled labor required for installation, and space limitations within residential

and commercial settings hinder the advancement and expansion of waste heat recovery.

For residential and commercial systems, it is practical to purchase systems that

are very dependable, hence the acquisition of separate components for water heating and

space temperature conditioning is favored over integrated heat recovery systems that

could have an impact on every building in the residential and commercial sector.

However, with novel ways to recover some of the energy, benefits will be significant.

The main objective of this study is to conduct a thorough and critical review of low-

temperature waste heat recovery in residential and commercial settings. Current

applications of waste heat recovery will be identified, and the potential of emerging

systems assessed.

2

Definition of Concept

In residential and commercial settings, most waste-heat recovery efforts focus on

discarded heat from drains, the condenser of heat pumps, and a few key appliances. Heat

pumps and heat exchangers can be used to recover heat from wastewater. Using a heat

pump, wastewater could provide a heat source for the evaporator. Alternatively, using a

heat exchanger, wastewater could be used to preheat tap water. In appliances like clothes

dryers or dishwashers, instead of discarding heated fluids (air or water) to the

environment, a heat exchanger could be used to recover some of the waste heat. Recovery

of condenser waste heat is carried out in a heat pump when the operating function of the

heat pump is space cooling. The three forms of waste heat recovery in residential and

commercial settings are heat exchanger, heat pump, and hybrid waste heat recovery.

Hybrid waste heat recovery is a combination of heat exchanger and heat pump heat

recovery.

Conventional Heat Exchanger Heat Recovery

Heat exchanger heat recovery is an obvious form of waste heat recovery. It is

generally inexpensive, and requires the least space. Not functioning as a component of a

refrigeration cycle, these systems have been designed to recover waste heat exclusively

from drains. They preheat water using single pass counter flow heat exchangers [1][7].

Wong et al concluded that a horizontal heat exchanger in a shower drain could save

between 4% and 15% of energy consumed on hot water showers annually [1]. Leidl et al

3

stated that vertical heat exchangers could recover between 52% and 72% of the heat from

shower wastewater [7]. These values are believed to be relative to the temperature of tap

water, so could be interpreted as heat exchanger efficiency. A reason behind the vertical

counter flow heat exchanger’s superior efficiency to its horizontal counterpart is

discussed on page 8. Novel heat exchanger waste heat recovery systems comprise heat

exchangers designs deviating from the canonical, with the resolution to optimize cost or

effectiveness. There are other novel heat exchanger heat recovery systems with

applications within appliances.

Novel Heat Exchanger Heat Recovery

The main objective of Paepe et al was to develop a prototype to recover warm

wastewater out of one dishwasher cycle and use it as a heat source for tap water to be

used in the subsequent cycle that requires hot water [3]. A quasi-steady calculation model

was developed for the proposed swirl inlet system to be used for heat recovery.

Experimental results validated the developed model. Using a tube length of 15 m inside a

5.5-liter tank, heat recovery of 25% was achieved. With payback on initial investment of

6 years, the swirl inlet filling system was determined to be an economical means to

exchange heat between tap water and wastewater for a dishwasher. Figure 1 shows the

proposed prototype.

4

Figure 1: Principal design of the recovery system for a dishwasher and the swirl

inlet system [3]

The main objective of Guo et al was to determine the energy savings potential of

a heat exchanger particularly designed to recover waste heat from the shower drainage

[9]. Unlike other drain heat exchangers, in this device, wastewater preheats tap water

twice before it reaches the water heater. The device performance was obtained through

experimentation. This system recovers more than 50% of waste heat. Figure 2 shows the

designed heat exchanger.

Figure 2: Schematic diagram of waste heat recovery device [9]

5

A lot of residences are space constrained, therefore a convenient location for the

placement of a waste heat recovery heat exchanger is beneath the shower stall / bath tub.

Unless the apartment is on the ground floor, a horizontally oriented counter flow heat

exchanger is a more suitable fit than its vertical counterpart. The authors of this paper

proposed a design that optimizes horizontal counter flow heat exchangers in order to

make them just as effective as vertical counter flow heat exchangers [14]. McNabola et al

improved the horizontal counter flow heat exchanger by optimizing film flow heat

transfer, which is the fundamental characteristic behind high efficiency heat transfer in

vertical counter flow heat exchangers. Furthermore, this system is cost effective since

plastic pipes were used for the wastewater tubing as opposed to copper in vertical counter

flow heat exchangers. CFD simulations were proven to accurately predict experimental

results before system optimization was carried out using CFD. CFD optimization shows

that this system can recover waste heat at efficiencies above 50%. Figure 3 shows the

cross section of the proposed heat exchanger.

Figure 3: Cross section of the proposed drain waste heat recovery device [14]

6

Conventional Heat Pump Heat Recovery

Heat recovery heat pumps have been designed to recover condenser waste heat by

using water-cooled condensers to produce hot water. Jiang, and Jie et al designed systems

for all combinations of space heating, space cooling, and water heating [4][25]. These

heat pumps have five functions: space cooling, space cooling and water heating, space

heating, space heating and water heating, and water heating. Because space heating and

water heating at the same time requires a heating capacity that may overwhelm the heat

pump in the winter, due to low ambient temperature heat sources, some heat pumps were

designed to perform only four of the five combinations previously mentioned [6][11][18];

the space heating and water heating function being excluded. Other heat pumps have

been designed solely for water heating [13][19]. Baek et al used the wastewater from

saunas and public baths in a hotel as a heat source for a heat pump water heater that

maintains a coefficient of performance between 4.5 and 5 throughout the year [13].

For regular heat pump waste heat recovery systems, the coefficient of

performance of the heat pump rises, and then falls, during any operating mode that

includes water heating. The coefficient of performance rises initially because condenser

waste heat is being used to heat water. However, the temperature differential between

water and condensing refrigerant eventually decreases such that the heating capacity and

cooling capacity of the heat pump drop as well. Consequently, the coefficient of

performance of the system drops. The heat pump performance is not stable. Another issue

that arises with regular air-source heat pump heat recovery systems is the low speed of

production of hot water, especially in the winter when ambient temperatures are low.

7

Even when hot water is produced and stored, because there is no heater in the water tank

to maintain water temperature, heat is lost when the need for hot water is not urgent.

Heat pump waste heat recovery systems could be novel for design modifications

that result cost-effectiveness, steady performance, water heating speed increase, hot water

storage enhancement, multiple heat source incorporation, or condenser waste heat

utilization for purposes other than water heating. Heat pump water heaters are stable

when they employ air-cooled condensers that are operated as the heating capacity of the

water-cooled condenser drops. Using wastewater-source evaporators solely, in parallel

with, or in series with air-source evaporators could enhance the performance of the heat

pump in the winter, speeding up water heating. Besides ensuring that energy expended on

heating is not wasted, optimizing hot water storage will ensure hot water is always be

readily available.

Novel Heat Pump Heat Recovery

Deng et al investigated the energy saving potential of split-type residential air

conditioners used for clothes drying through condenser waste heat in tropical and sub

tropical regions [5]. The system performance was obtained through experimentation. This

energy consumption by this unit is 1.2 % that of an electric tumbler dryer. This energy

consumed is used to increase the condenser fan speed so that the original condenser

airflow rate, without with loaded drying rack, is maintained. Deng only provided a

schematic of the experimental set up for the residential air conditioner (RAC), which is

shown in figure 4.

8

Figure 4: Schematic diagram of the laboratory experiment rig [5]

Devised for year round operation, Shao et al proposed a heat pump that has been

designed for various combinations of space heating, space cooling, and water heating

[12]. This system comprises a reheater that absorbs heat into domestic water from

superheated refrigerant, and a preheater that absorbs heat into domestic water from

subcooled refrigerant. The performance of this system is stable because reheaters and

preheaters are used for water heating, as opposed to the system condenser. Additionally,

in order to prevent the problem of insufficient hot water in the winter, water can be

pumped from the tank and stored in the reheater, keeping it heated and available when the

need arises. The system performance was determined using a simulation model of an

inverter air conditioner. Working purely as a water heater, a COP of 4 is attained

compared to 1 for an electric water heater. This system has 31.1% energy saving

compared to a heat pump plus electric water heating system per year. It has an annual

9

performance factor of 3.201 compared to 2.207 of a heat pump plus electric water heater.

Figure 5 shows the proposed heat pump system.

Figure 5: Schematic diagram of the heat pump system [12]

Liu et al discussed the use of wastewater source only or both wastewater and air

sources in order to optimize heat pump heat recovery for heating in residences [15].

During winter, due to low ambient temperatures, wastewater source alone is best for the

heat pump. Otherwise, engaging wastewater and air sources in parallel yields the best

heating capacity and coefficient of performance of the system compared to using both

heat sources in series or alone. Unlike in the hot water supply only mode where two heat

exchangers are used to heat up water, in the space heating plus hot water supply mode,

the smaller of the two heat exchangers is used for water heating, and the remaining heat

from the refrigerant is used for space heating. This is an alternative to increasing

compressor speed during peak load periods, which increases power input. In hot water

supply mode only, the coefficient of performance and heating capacity of the system

steadily drops with increase in water temperature. In space heating plus hot water supply

mode, the system performance is much more stable despite water temperature rise

because refrigerant heat is released to the space, though a drop in coefficient of

10

performance and heating capacity is noticeable still. Figure 6 shows the proposed heat

pump system.

Figure 6: Schematic diagram of the multifunctional heat pump system [15]

Liu et al discussed the use of wastewater source only or both wastewater and air

sources in order to optimize heat pump heat recovery for cooling in residences [16]. An

air heat exchanger is placed in series after the water heat exchanger for hot water

production because it is required in order to produce water at up to 49°C. This air heat

exchanger was run in both forced and natural convection. The natural convection mode

produced hot water faster. The measured system performance was obtained through

experimentation. Figure 7 shows the proposed heat pump system.

11


In this paper, the transient operating characteristics of a heat pump water heater in

single stage and cascade mode was investigated through dynamic experiments and

analysis [17]. In the water heater, Wu et al have placed phase change materials within the

storage tank of the heat pump. With phase change materials in the hot water storage tank,

water can stay at higher temperatures for longer. Hence, there is less heat loss when hot

water is not being used and off electricity peak periods when the heat pump may not be in

use. Cascade mode has a higher coefficient of performance in cold ambient temperatures

and single stage mode performs better in warmer ambient temperatures. The critical point

to switch between both modes depends on ambient temperature and hot water

temperature. The coefficient of performance for the single stage mode ranges between 1.5

and 3.05 for ambient air conditions of -7°C and 20°C respectively. For the cascade mode,

12

and the same ambient temperatures, coefficient of performance ranges between 1.74 and

2.55. Figure 8 shows the proposed heat pump system.


A heat pump water heater designed by Huang et al to produce hot water rapidly

by using a mechanical heat-sensitive device made from shape memory alloy was

introduced [20]. In this system, a supply tank comprising a water-cooled condenser and a

holding tank for storing hot water was proposed in order to separate water into smaller

portions so it can be heated to desirable temperatures much quicker. The shape memory

alloy valve connecting both tanks opens when water temperature in the supply tank

exceeds 50°C. The measured system performance was obtained through experimentation.

This system does not need an auxiliary water heater in cold ambient conditions since is it

has fast temperature response. For ambient temperatures between 6°C and 38°C, the

13

temperature response speed is 0.714°C/min and 0.483°C/min in the supply and holding

tanks respectively, before the shape memory alloy valve opens. After it opens, the

temperature response speed increases to 1.234°C /min and 1.1°C /min for the supply and

holding tanks respectively. This heat pump water heater is also energy efficient; using a

maximum of 0.016KW/l, while a regular electric system uses 0.06kW/l of energy to heat

water up to 55°C. Figure 9 shows the proposed heat pump system.


Because hot water demand is not stable, Gu et al proposed a heat pump water

heater enhanced with phase change materials of lower and higher melting points designed

to store latent and sensible heat respectively [22]. These materials store condenser waste

heat that is utilized when there is demand for hot water. The phase change material

commonly used is paraffin wax, and it has been applied to this system. Typically,

paraffin wax has low resistance when absorbing heat, thus it experiences large

14

temperature rise. On the other hand, when releasing heat, paraffin has high heat transfer

resistance. It does not transfer as much heat to water as is required. Furthermore, it

experiences a sharp decline in temperature when heat is being transferred to water.

Experiments were carried out to determine how much additive to be added to technical

grade paraffin wax such that it can satisfy household temperature demand. Paraffin wax

with 40% liquid paraffin as the additive was used for heat recovery because it is an

economical option. The performance of this system is stable since a cooling tower is used

when the accumulators cannot take all the heat out of the refrigerant. When hot water is

required, tap water flows through the accumulators containing phase change material and

can reach between 40°C and 45°C on exiting the accumulators. An auxiliary electric

heater is used if further heating is required. Figure 10 shows the proposed heat pump

system.

Figure 10: Schematic diagram of the air conditioning system with thermal energy

recovery devices [22]

15

Bertsch et al proposed a heat pump water heater designed to perform efficiently in

extremely cold weather conditions, supplying water at 50°C in ambient conditions as low

as -30°C [28]. In warmer ambient temperatures, single stage mode is used, and the two-

stage mode is used in cold ambient temperatures due to the resulting increase in heating

capacity. An economizer within the heat pump cycle is used to prevent the compressor

temperature from rising too high and to improve coefficient of performance by

subcooling refrigerant exiting the condenser before it enters the expansion valve. As

opposed to a conventional heat pump, which has a coefficient of performance less than 2

in the winter, this system has a coefficient of performance of at least 2.3 in extremely

cold weather. Figure 11 shows the proposed heat pump system.

Figure 11: Two-stage cycle with closed economizer [28]

16

Conventional Hybrid Heat Recovery

Utilizing wastewater as a heat source, a heat exchanger comprising wastewater

can be used to preheat tap water, and after exiting the heat exchanger, the remaining heat

in the wastewater can serve as the heat source for a heat pump designed for further tap

water heating through condenser waste heat [10][23][24][26]. Sun et al applied this form

of waste heat recovery to a barber’s shop and reduced the yearly cost of water heating by

93.7% [10]. Liu et al proposed this system for water heating in public shower facilities

with a gas boiler used for auxiliary heating in the event that the hot water produced by the

heat pump is insufficient [23]. The gas boiler replaced the ubiquitous auxiliary electric

heater because it produced fewer emissions. In the event that wastewater is not available,

Zeshao et al designed a system that uses either or both wastewater and air heat sources in

the heat pump [24]. Hybrid systems provide heated water at higher temperatures and have

higher heat pump coefficient of performance [26]. Novel hybrid waste heat recovery

systems comprise designs with resolution to optimize heat recovery in a manner similar

to heat exchanger and heat pump waste heat recovery systems.

Novel Hybrid Heat Recovery

Because ambient conditions are unstable (due to varying seasonal weather

conditions), Wei et al have proposed shower wastewater as the heat source for a heat

pump water heater [8]. A shell and tube heat exchanger for transferring heat from

wastewater to tap water is also part of the design. This system is unique because tap

17

water is split into two streams to be heated separately by the heat pump condenser and the

heat exchanger. Both streams are eventually mixed. No water storage tank is required;

hence this system is likely to satisfy space requirements. Furthermore, the performance of

this system is stable because tap water constantly runs across the condenser; therefore the

heating capacity of the condenser is optimum, and varies slightly depending on the

effects of ambient conditions on tap water. A mathematical set of equations developed to

model the physics of every component of the system was solved using MATLAB. The

optimized coefficient of performance of the heat pump is 4.97. Figure 12 shows the

proposed hybrid system.

Figure 12: Schematic of the heat pump bath water heating system [8]

Wang et al discussed the use of wastewater and air heat sources for a

multifunction heat pump designed for space cooling and water heating [27]. Wastewater

is a reliable heat source in the winter when ambient air temperatures are low. Besides

having no valves, hence reducing cost, this system can produce hot water above 36°C just

13 seconds after being turned on in the summer. This work is novel because it has an

optimized cycle. A heat exchanger has been placed after the water evaporator to further

heat up refrigerant entering the compressor by using refrigerant exiting the condenser.

18

Consequently, refrigerant exiting the condenser is sub-cooled, improving system

performance. The measured system performance was obtained through experimentation.

The coefficient of performance of this system ranges between 3.69 and 5.70. The

payback time on initial investment is 5.5 years. Figure 13 shows the proposed hybrid

system.

Figure 13: Schematic diagram of the multifunctional heat pump [27]

19

Conclusions

A literature review of low temperature waste heat recovery in residential

and commercial settings was conducted. Heat discarded via drains and the

condenser of heat pumps were identified as the main sources of waste heat, and the

potential of emerging systems that have been proposed for heat recovery was

assessed. In order to support future research, the main conclusions that can be

drawn from this study are listed as follows:

- The most efficient form of waste heat recovery is hybrid waste heat recovery.

Heat exchanger heat recovery is the cheapest and requires the least space.

- For drains, heat exchangers in the horizontal orientation better satisfy space

constraints. They can be designed and optimized to perform just as well as

heat exchangers in the vertical orientation.

- Unless an economizer or air-cooled condenser is included in a heat pump

cycle to further cool refrigerant exiting the water-cooled condenser being

used to heat water, which recirculates from a tank, the performance of the

heat pump will not be stable.

- Wastewater as the heat source for a heat pump can ensure reliable year

round performance. For cascade air-source heat pumps, the single stage

mode is used in warmer ambient temperatures, and switched to the two-

stage mode in the winter due to the resulting increasing in heat capacity.

20

- The use of phase change materials to store thermal energy ensures the

availability of water at high temperatures for longer periods of time after hot

water has been produced.

21

References

[1] L.T. Wong, K.W. Mui, Y. Guan, Shower water heat recovery in high-rise residential

buildings of Hong Kong, Applied Energy, Volume 87, Issue 2, February 2010, Pages

703-709, ISSN 0306-2619, http://dx.doi.org/10.1016/j.apenergy.2009.08.008.

(http://www.sciencedirect.com/science/article/pii/S0306261909003225)

[2] H.I. Abu-Mulaweh, Design and performance of a thermosiphon heat recovery system,

Applied Thermal Engineering, Volume 26, Issues 5–6, April 2006, Pages 471-477, ISSN

1359-4311, http://dx.doi.org/10.1016/j.applthermaleng.2005.08.003.


[3] M De Paepe, E Theuns, S Lenaers, J Van Loon, Heat recovery system for

dishwashers, Applied Thermal Engineering, Volume 23, Issue 6, April 2003, Pages 743-

756, ISSN 1359-4311, http://dx.doi.org/10.1016/S1359-4311(03)00016-4.


[4] Huimin Jiang, Yiqiang Jiang, Yang Wang, Zuiliang Ma, Yang Yao, An experimental

study on a modified air conditioner with a domestic hot water supply (ACDHWS),

Energy, Volume 31, Issue 12, September 2006, Pages 1789-1803, ISSN 0360-5442,

http://dx.doi.org/10.1016/j.energy.2005.07.004.


[5] Shiming Deng, Hua Han, An experimental study on clothes drying using rejected heat

(CDURH) with split-type residential air conditioners, Applied Thermal Engineering,

Volume 24, Issues 17–18, December 2004, Pages 2789-2800, ISSN 1359-4311,

http://dx.doi.org/10.1016/j.applthermaleng.2004.03.016.


[6] Jie Ji, Tin-tai Chow, Gang Pei, Jun Dong, Wei He, Domestic air-conditioner and

integrated water heater for subtropical climate, Applied Thermal Engineering, Volume

23, Issue 5, April 2003, Pages 581-592, ISSN 1359-4311,

http://dx.doi.org/10.1016/S1359-4311(02)00228-4.


[7] Chantelle M. Leidl, W. David Lubitz, Comparing domestic water heating

technologies, Technology in Society, Volume 31, Issue 3, August 2009, Pages 244-256,

ISSN 0160-791X, http://dx.doi.org/10.1016/j.techsoc.2009.06.005.

(http://www.sciencedirect.com/science/article/pii/S0160791X09000591)

[8] Wei Chen, Shiqiang Liang, Yongxian Guo, Keyong Cheng, Xiaohong Gui, Dawei

Tang, Investigation on the thermal performance and optimization of a heat pump water

heater assisted by shower waste water, Energy and Buildings, Volume 64, September

2013, Pages 172-181, ISSN 0378-7788, http://dx.doi.org/10.1016/j.enbuild.2013.04.021.


http://www.sciencedirect.com/science/article/pii/S0306261909003225






http://www.sciencedirect.com/science/article/pii/S0160791X09000591


22

[9] Yong-xian Guo, Ying-lin Cai, Shi-qiang Liang, Wei Chen, Experimental Study on a

Shower Waste Water Heat Recovery Device in Buildings, Applied Mechanics and

Materials, Volume 226 - 228, November 2012, Pages 2402 – 2406.

[10] Fangtian Sun, Na Wang, Yunze Fan, Deying Li, Research on Waste Heat Recovery

in Drain Water of Barbershop, Applied Mechanics and Materials, Volume 204 - 208,

October 2012, Pages 4229 – 4233.

[11] Guangcai Gong, Wei Zeng, Liping Wang, Chih Wu, A new heat recovery technique

for air-conditioning/heat-pump system, Applied Thermal Engineering, Volume 28, Issues

17–18, December 2008, Pages 2360-2370, ISSN 1359-4311,


(http://www.sciencedirect.com/science/article/pii/S135943110800046X)

[12] Shuangquan Shao, Wenxing Shi, Xianting Li, Jie Ma, A new inverter heat pump

operated all year round with domestic hot water, Energy Conversion and Management,

Volume 45, Issues 13–14, August 2004, Pages 2255-2268, ISSN 0196-8904,

http://dx.doi.org/10.1016/j.enconman.2003.10.013.


[13] N.C. Baek, U.C. Shin, J.H. Yoon, A study on the design and analysis of a heat pump

heating system using wastewater as a heat source, Solar Energy, Volume 78, Issue 3,

March 2005, Pages 427-440, ISSN 0038-092X,

http://dx.doi.org/10.1016/j.solener.2004.07.009.

(http://www.sciencedirect.com/science/article/pii/S0038092X04002014)

[14] Aonghus McNabola, Killian Shields, Efficient drain water heat recovery in

horizontal domestic shower drains, Energy and Buildings, Volume 59, April 2013, Pages

44-49, ISSN 0378-7788, http://dx.doi.org/10.1016/j.enbuild.2012.12.026.


[15] Xiaoyu Liu, Siu-Kit Lau, Haorong Li, Optimization and analysis of a multi-

functional heat pump system with air source and gray water source in heating mode,

Energy and Buildings, Volume 69, February 2014, Pages 1-13, ISSN 0378-7788,

http://dx.doi.org/10.1016/j.enbuild.2013.09.039.


[16] Xiaoyu Liu, Long Ni, Siu-Kit Lau, Haorong Li, Performance analysis of a multi-

functional heat pump system in cooling mode, Applied Thermal Engineering, Volume 59,

Issues 1–2, 25 September 2013, Pages 253-266, ISSN 1359-4311,



[17] Jianghong Wu, Zhaoguang Yang, Qinghao Wu, Yujuan Zhu, Transient behavior and

dynamic performance of cascade heat pump water heater with thermal storage system,

Applied Energy, Volume 91, Issue 1, March 2012, Pages 187-196, ISSN 0306-2619,

http://www.sciencedirect.com/science/article/pii/S135943110800046X


http://www.sciencedirect.com/science/article/pii/S0038092X04002014




23

http://dx.doi.org/10.1016/j.apenergy.2011.09.020.


[18] Jie Ji, Gang Pei, Tin-tai Chow, Wei He, Aifeng Zhang, Jun Dong, Hua Yi,

Performance of multi-functional domestic heat-pump system, Applied Energy, Volume

80, Issue 3, March 2005, Pages 307-326, ISSN 0306-2619,



[19] J.J. Guo, J.Y. Wu, R.Z. Wang, S. Li, Experimental research and operation

optimization of an air-source heat pump water heater, Applied Energy, Volume 88, Issue

11, November 2011, Pages 4128-4138, ISSN 0306-2619,



[20] B.J. Huang, J.H. Wang, J.H. Wu, P.E. Yang, A fast response heat pump water heater

using thermostat made from shape memory alloy, Applied Thermal Engineering, Volume

29, Issue 1, January 2009, Pages 56-63, ISSN 1359-4311,



[21] Xuelai Zhang, Shuxuan Yu, Mei Yu, Yuanpei Lin, Experimental research on

condensing heat recovery using phase change material, Applied Thermal Engineering,

Volume 31, Issues 17–18, December 2011, Pages 3736-3740, ISSN 1359-4311,



[22] Zhaolin Gu, Hongjuan Liu, Yun Li, Thermal energy recovery of air conditioning

system––heat recovery system calculation and phase change materials development,

Applied Thermal Engineering, Volume 24, Issues 17–18, December 2004, Pages 2511-

2526, ISSN 1359-4311, http://dx.doi.org/10.1016/j.applthermaleng.2004.03.017.


[23] Lanbin Liu, Lin Fu, Shigang Zhang, The design and analysis of two exhaust heat

recovery systems for public shower facilities, Applied Energy, Volume 132, 1 November

2014, Pages 267-275, ISSN 0306-2619,



[24] Chen ZeShao, Tao WenQuan, Zhu YanWen, Hu Peng, Performance analysis of air-

water dual source heat pump water heater with heat recovery, Science China

Technological Science, Volume 55, August 2012, Pages 2148 - 2156, ISSN 1674-7321,

http://dx.doi.org/10.1007/s11431-012-4905-7.

[25] Changyong Cho, Jong Min Choi, Experimental investigation of a multi-function heat

pump under various operating modes, Renewable Energy, Volume 54, June 2013, Pages








24

253-258, ISSN 0960-1481, http://dx.doi.org/10.1016/j.renene.2012.07.017.


[26] Ali Kahraman, Alaeddin Celebi, Investigation of the performance of a heat pump

using waste water as a heat source, Energies, volume 2, August 2009, Pages 697-713.

[27] Handong Wang, Qin Wang, Guangming Chen, Experimental performance analysis

of an improved multifunctional heat pump system, Energy and Buildings, Volume 62,

July 2013, Pages 581-589, ISSN 0378-7788,

http://dx.doi.org/10.1016/j.enbuild.2013.04.001.


[28] Stefan S. Bertsch, Eckhard A. Groll, Two-stage air-source heat pump for residential

heating and cooling applications in northern U.S. climates, International Journal of

Refrigeration, Volume 31, Issue 7, November 2008, Pages 1282-1292, ISSN 0140-7007,

http://dx.doi.org/10.1016/j.ijrefrig.2008.01.006.


[29] U.S. Energy Information Administration. Consumption & Efficiency. 25 6 2015. 1 7

2015 http://www.eia.gov/consumption/.

[30] U.S. Energy Information Administration. Today In Energy. 7 3 2013. 1 7 2015

http://www.eia.gov/todayinenergy/detail.cfm?id=10271.




http://www.eia.gov/consumption/

http://www.eia.gov/todayinenergy/detail.cfm?id=10271

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