Evaluation of Heat Pump Water Heater Performance and Optimization Strategies In Cold Climates

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Total Pages : pages
Book Rating : 4.:/5 (13 download)

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Book Synopsis Evaluation of Heat Pump Water Heater Performance and Optimization Strategies In Cold Climates by : Jayson Bursill

Download or read book Evaluation of Heat Pump Water Heater Performance and Optimization Strategies In Cold Climates written by Jayson Bursill and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Cold Climates Heat Pump Design Optimization

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ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (16 download)

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Book Synopsis Cold Climates Heat Pump Design Optimization by :

Download or read book Cold Climates Heat Pump Design Optimization written by and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Heat pumps provide an efficient heating method; however they suffer from sever capacity and performance degradation at low ambient conditions. This has deterred market penetration in cold climates. There is a continuing effort to find an efficient air source cold climate heat pump that maintains acceptable capacity and performance at low ambient conditions. Systematic optimization techniques provide a reliable approach for the design of such systems. This paper presents a step-by-step approach for the design optimization of cold climate heat pumps. We first start by describing the optimization problem: objective function, constraints, and design space. Then we illustrate how to perform this design optimization using an open source publically available optimization toolbox. The response of the heat pump design was evaluated using a validated component based vapor compression model. This model was treated as a black box model within the optimization framework. Optimum designs for different system configurations are presented. These optimum results were further analyzed to understand the performance tradeoff and selection criteria. The paper ends with a discussion on the use of systematic optimization for the cold climate heat pump design.

Summer Indoor Heat Pump Water Heater Evaluation in a Hot-Dry Climate

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ISBN 13 :
Total Pages : 0 pages
Book Rating : 4.:/5 (14 download)

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Book Synopsis Summer Indoor Heat Pump Water Heater Evaluation in a Hot-Dry Climate by :

Download or read book Summer Indoor Heat Pump Water Heater Evaluation in a Hot-Dry Climate written by and published by . This book was released on 2017 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Heat pump water heaters offer a significant opportunity to improve water heating performance for the over 40% of U.S. households that heat domestic hot water using electric resistance storage water heaters. Numerous field studies have also been completed documenting performance in a variety of climates and applications. More recent evaluation efforts have focused attention on the performance of May through September 2014, with ongoing winter monitoring being sponsored by California utility partners. Summer results show favorable system performance with extrapolated annual water heating savings of 1,466 to 2,300 kWh per year, based on the observed hot water loads. Additional summer space cooling benefits savings of 121 to 135 kWh per year were projected, further increasing the water energy savings.

Laboratory Performance Evaluation of Residential Integrated Heat Pump Water Heaters

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ISBN 13 :
Total Pages : 77 pages
Book Rating : 4.:/5 (16 download)

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Book Synopsis Laboratory Performance Evaluation of Residential Integrated Heat Pump Water Heaters by :

Download or read book Laboratory Performance Evaluation of Residential Integrated Heat Pump Water Heaters written by and published by . This book was released on 2014 with total page 77 pages. Available in PDF, EPUB and Kindle. Book excerpt: This paper explores the laboratory performance of five integrated Heat Pump Water Heaters (HPWHs) across a wide range of operating conditions representative of US climate regions. HPWHs are expected to provide significant energy savings in certain climate zones when compared to typical electric resistance water heaters. Results show that this technology is a viable option in most climates, but differences in control schemes and design features impact the performance of the units tested. Tests were conducted to map heat pump performance across the operating range and to determine the logic used to control the heat pump and the backup electric heaters. Other tests performed include two unique draw profile tests, reduced air flow performance tests and the standard DOE rating tests. The results from all these tests are presented here for all five units tested. The results of these tests will be used to improve the EnergyPlus heat pump water heater for use in BEopt(tm) whole-house building simulations.

Performance Analysis of Heat Pump Water Heater Systems in Hot-humid Climates

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ISBN 13 :
Total Pages : 160 pages
Book Rating : 4.:/5 (959 download)

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Book Synopsis Performance Analysis of Heat Pump Water Heater Systems in Hot-humid Climates by : Obinna Uyanna

Download or read book Performance Analysis of Heat Pump Water Heater Systems in Hot-humid Climates written by Obinna Uyanna and published by . This book was released on 2016 with total page 160 pages. Available in PDF, EPUB and Kindle. Book excerpt: The current overdependence on fossil fuel as the means of energy generation ensures that eventually, energy and utility costs will be extremely high since these fossil materials are depletive in nature. However, the research and development of energy efficient devices offers a viable solution to this situation. One such device is the heat pump water heater (HPWH), a device that utilizes a reverse refrigeration cycle to generate domestic hot water (DHW) for residential use. The performance of HPWHs in hot-humid climates was analyzed since such areas have high solar energy concentration, especially in the summer. Although electric resistance water heaters (ER WHs) are currently the main source of DHW generation, HPWHs are believed to be the more efficient water heating option. In this work, BEopt, which is a building energy-optimization software, was used to perform simulations of HPWHs and ERWHs in two selected hot-humid climates. With certain user-defined inputs, four simulation cases were generated and tests were run that showed the performance of these water heaters. The results showed that HPWHs were immensely more efficient, having efficiencies of 3.3 and 3.56 in the two test location while ERWHs had efficiencies of 0.88 and 0.9. The results also showed a significant amount of utility savings, reduced consumed energy as well as reduced CO, emissions when compared to ERWHs. It was also shown in the results that the units with HPWHs had significantly higher cooling energy values when compared to units with ERWHs thus leading to a better space cooling and comfort level for occupants of homes on hot-humid climates.

Dynamic Modeling and Model-free Real-time Optimization for Cold Climate Heat Pump Systems

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ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (114 download)

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Book Synopsis Dynamic Modeling and Model-free Real-time Optimization for Cold Climate Heat Pump Systems by : Wenyi Wang

Download or read book Dynamic Modeling and Model-free Real-time Optimization for Cold Climate Heat Pump Systems written by Wenyi Wang and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Air source heat pump (ASHP) has been a well-received technology to provide space and/or water heating for building and industrial applications, while its efficiency and heating capacity can be severely limited when operated in cold climate. Various modifications have been proposed for cold-climate operation of ASHP over the single-stage refrigeration cycle, such as vapor injection techniques and cascade configuration. However, there has been a lack of effective control strategies for such systems to maintain the optimal energy efficiency for operations across different combinations of ambient and load conditions. Previous work has paid great efforts in model based strategies, anchored on deriving system models with simulation and experimental testing. Such approaches can be prohibitively expensive due to the inherent nonlinear nature of refrigeration systems and unmeasurable equipment degradation. This dissertation investigates on model-free control strategies for real-time efficiency optimization for several configurations of cold-climate ASHP, by use of Extremum Seeking Control (ESC). By utilizing periodic dither inputs for online gradient estimation, ESC bears significant robustness against process variation and external disturbance, which has proved to be more advantageous in handling the challenging applications like heating, ventilation and air conditioning (HVAC) systems. Three types of ASHP configurations are studied in this dissertation: the internal heat exchanger vapor injection, flash-tank vapor injection, and cascade configuration. For both vapor injection ASHP configurations, the intermediate pressure setpoint is optimized by standard ESC and Newton-based ESC based on the feedback of the total power consumption, with the constant heating load considered. For the cascade ASHP, multivariable ESC is designed to handle two operational scenarios: minimizing the total power for fixed heating capacity and maximizing the coefficient of performance (COP) for variable heating capacity. For the power based ESC, the manipulated inputs include the intermediate temperature, high temperature cycle superheat and low temperature cycle superheat; while for the COP based ESC, the high- and low-temperature cycle compressor speeds and evaporator fan mass flow rate are adopted as inputs. The proposed ESC strategies are evaluated with Modelica based dynamic simulation models of the three system configurations. Simulations have been conducted under both fixed and realistic ambient temperature profiles. The simulation results show good steady-state and transient performance of real-time efficiency optimization with the proposed strategies, in terms of tracking unknown and dynamic optimum settings.

Laboratory Performance Evaluation of Residential Integrated Heat Pump Water Heaters

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ISBN 13 :
Total Pages : 70 pages
Book Rating : 4.:/5 (13 download)

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Book Synopsis Laboratory Performance Evaluation of Residential Integrated Heat Pump Water Heaters by : Bethany Sparn

Download or read book Laboratory Performance Evaluation of Residential Integrated Heat Pump Water Heaters written by Bethany Sparn and published by . This book was released on 2011 with total page 70 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report discusses how domestic hot water heating can be a significant opportunity for energy savings. An emerging technology has recently arrived in the U.S. market: the residential integrated heat pump water heater (HPWH). A laboratory evaluation is presented of the five integrated HPWHs available in the U.S. today.

Multifamily Heat Pump Water Heater Evaluation

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ISBN 13 :
Total Pages : 0 pages
Book Rating : 4.:/5 (14 download)

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Book Synopsis Multifamily Heat Pump Water Heater Evaluation by :

Download or read book Multifamily Heat Pump Water Heater Evaluation written by and published by . This book was released on 2013 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Although heat pump water heaters (HPWHs) have gained significant attention in recent years as a high efficiency electric water heating solution for single family homes, central HPWHs for commercial or multi-family applications are not as well documented in terms of measured performance and cost effectiveness. To evaluate this technology, the Alliance for Residential Building Innovation team monitored the performance of a 10.5 ton central HPWH installed on a student apartment building at the West Village Zero Net Energy Community in Davis, California. Monitoring data collected over a 16 month period were then used to validate a TRNSYS simulation model. The TRNSYS model was then used to project performance in different climates using local electric rates. Results of the study indicate that after some initial commissioning issues, the HPWH operated reliably with an annual average efficiency of 2.12 (Coefficient of Performance). The observed efficiency was lower than the unit's rated efficiency, primarily due to the fact that the system rarely operated under steady-state conditions. Changes in the system configuration, storage tank sizing, and control settings would likely improve the observed field efficiency. Modeling results suggest significant energy savings relative to electric storage water heating systems (typical annual efficiencies around 0.90) providing for typical simple paybacks of six to ten years without any incentives. The economics versus gas water heating are currently much more challenging given the current low natural gas prices in much of the country. Increased market size for this technology would benefit cost effectiveness and spur greater technology innovation.

Multifamily Heat Pump Water Heater Evaluation

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ISBN 13 :
Total Pages : 33 pages
Book Rating : 4.:/5 (985 download)

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Book Synopsis Multifamily Heat Pump Water Heater Evaluation by : M. Hoeschele

Download or read book Multifamily Heat Pump Water Heater Evaluation written by M. Hoeschele and published by . This book was released on 2017 with total page 33 pages. Available in PDF, EPUB and Kindle. Book excerpt: Although heat pump water heaters (HPWHs) have gained significant attention in recent years as a high efficiency electric water heating solution for single family homes, central HPWHs for commercial or multi-family applications are not as well documented in terms of measured performance and cost effectiveness. To evaluate this technology, the Alliance for Residential Building Innovation team monitored the performance of a 10.5 ton central HPWH installed on a student apartment building at the West Village Zero Net Energy Community in Davis, California. Monitoring data collected over a 16 month period were then used to validate a TRNSYS simulation model. The TRNSYS model was then used to project performance in different climates using local electric rates. Results of the study indicate that after some initial commissioning issues, the HPWH operated reliably with an annual average efficiency of 2.12 (Coefficient of Performance). The observed efficiency was lower than the unit's rated efficiency, primarily due to the fact that the system rarely operated under steady-state conditions. Changes in the system configuration, storage tank sizing, and control settings would likely improve the observed field efficiency. Modeling results suggest significant energy savings relative to electric storage water heating systems (typical annual efficiencies around 0.90) providing for typical simple paybacks of six to ten years without any incentives. The economics versus gas water heating are currently much more challenging given the current low natural gas prices in much of the country. Increased market size for this technology would benefit cost effectiveness and spur greater technology innovation

West Village Community

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ISBN 13 :
Total Pages : 37 pages
Book Rating : 4.:/5 (827 download)

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Book Synopsis West Village Community by :

Download or read book West Village Community written by and published by . This book was released on 2012 with total page 37 pages. Available in PDF, EPUB and Kindle. Book excerpt: West Village, a multi-use project underway at the University of California Davis, represents a ground-breaking sustainable community incorporating energy efficiency measures and on-site renewable generation to achieve community-level Zero Net Energy (ZNE) goals. The project when complete will provide housing for students, faculty, and staff with a vision to minimize the community's impact on energy use by reducing building energy use, providing on-site generation, and encouraging alternative forms of transportation. There are two primary objectives of this research. The first is to evaluate performance and efficiency of the central heat pump water heaters as a strategy to provide efficient electric water heating for net-zero all-electric buildings and where natural gas is not available on site. In addition, effectiveness of the quality assurance and quality control processes implemented to ensure proper system commissioning and to meet program participation requirements is evaluated. Recommendations for improvements that could improve successful implementation for large-scale, high performance communities are identified.

High Efficiency Water Heating Technology Development

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ISBN 13 :
Total Pages : 43 pages
Book Rating : 4.:/5 (946 download)

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Book Synopsis High Efficiency Water Heating Technology Development by : Van D. Baxter

Download or read book High Efficiency Water Heating Technology Development written by Van D. Baxter and published by . This book was released on 2016 with total page 43 pages. Available in PDF, EPUB and Kindle. Book excerpt: DOE has supported efforts for many years with the objective of getting a water heater that uses heat pump technology (aka a heat pump water heater or HPWH) successfully on the residential equipment market. The most recent previous effort (1999-2002) produced a product that performed very well in ORNL-led accelerated durability and field tests. The commercial partner for this effort, Enviromaster International (EMI), introduced the product to the market under the trade name Watter$aver in 2002 but ceased production in 2005 due to low sales. A combination of high sales price and lack of any significant infrastructure for service after the sale were the principal reasons for the failure of this effort. What was needed for market success was a commercial partner with the manufacturing and market distribution capability necessary to allow economies of scale to lead to a viable unit price together with a strong customer service infrastructure. General Electric certainly meets these requirements, and knowing of ORNL s expertise in this area, approached ORNL with the proposal to partner in a CRADA to produce a high efficiency electric water heater. A CRADA with GE was initiated early in Fiscal Year, 2008. GE initially named its product the Hybrid Electric Water Heater (HEWH).

Performance Evaluation of Add-on Heat Pump Water Heater Systems and Their Impacts on Utility Loads

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ISBN 13 :
Total Pages : 376 pages
Book Rating : 4.:/5 (643 download)

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Book Synopsis Performance Evaluation of Add-on Heat Pump Water Heater Systems and Their Impacts on Utility Loads by : Eric Gay

Download or read book Performance Evaluation of Add-on Heat Pump Water Heater Systems and Their Impacts on Utility Loads written by Eric Gay and published by . This book was released on 2010 with total page 376 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Building in Hot and Humid Regions

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Publisher : Springer
ISBN 13 : 9811375194
Total Pages : 219 pages
Book Rating : 4.8/5 (113 download)

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Book Synopsis Building in Hot and Humid Regions by : Napoleon Enteria

Download or read book Building in Hot and Humid Regions written by Napoleon Enteria and published by Springer. This book was released on 2019-04-26 with total page 219 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents an in-depth analysis covering climatic and weather conditions, house and building development history, construction methods and technologies, and environmental conditions. It provides relevant house and building information and highlights recent advances in hot and humid regions, as well as developments in other regions that are relevant to hot and humid climates. The countries in hot and humid regions, which include the tropical countries, the Middle Eastern countries around the Mediterranean, and many countries of Central Asia and Africa, are home to some of the most challenging conditions in the world in terms of house and building design and construction, and in terms of maintaining indoor thermal comfort and air quality in an energy-efficient way. The book’s respective chapters, prepared by expert contributors, cover essential concepts, designs, and construction methodologies for houses and commercial buildings. As such, the book offers a valuable resource for undergraduate and graduate students in architecture and engineering, house and building designers, and building sciences researchers. Building contractors, manufacturers and distributors of building equipment and devices, and government policymakers and legislators will also benefit from the information provided in this book.

Field Performance of Heat Pump Water Heaters in the Northeast

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ISBN 13 :
Total Pages : 0 pages
Book Rating : 4.:/5 (14 download)

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Book Synopsis Field Performance of Heat Pump Water Heaters in the Northeast by :

Download or read book Field Performance of Heat Pump Water Heaters in the Northeast written by and published by . This book was released on 2016 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Heat pump water heaters (HPWHs) are finally entering the mainstream residential water heater market. Potential catalysts are increased consumer demand for higher energy efficiency electric water heating and a new Federal water heating standard that effectively mandates use of HPWHs for electric storage water heaters with nominal capacities greater than 55 gallons. When compared to electric resistance water heating, the energy and cost savings potential of HPWHs is tremendous. Converting all electric resistance water heaters to HPWHs could save American consumers 7.8 billion dollars annually ($182 per household) in water heating operating costs and cut annual residential source energy consumption for water heating by 0.70 quads. Steven Winter Associates, Inc. embarked on one of the first in situ studies of these newly released HPWH products through a partnership with two sponsoring electric utility companies, National Grid and NSTAR, and one sponsoring energy efficiency service program administrator, Cape Light Compact. Recent laboratory studies have measured performance of HPWHs under various operating conditions, but publically available field studies have not been as available. This evaluation attempts to provide publicly available field data on new HPWHs by monitoring the performance of three recently released products (General Electric GeoSpring(TM), A.O. Smith Voltex(R), and Stiebel Eltron Accelera(R) 300). Fourteen HPWHs were installed in Massachusetts and Rhode Island and monitored for over a year. Of the 14 units, ten were General Electric models (50 gallon units), two were Stiebel Eltron models (80 gallon units), and two were A.O. Smith models (one 60-gallon and one 80-gallon unit).

Heat Pump Water Heater Technology Assessment Based on Laboratory Research and Energy Simulation Models

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ISBN 13 :
Total Pages : 34 pages
Book Rating : 4.:/5 (794 download)

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Book Synopsis Heat Pump Water Heater Technology Assessment Based on Laboratory Research and Energy Simulation Models by :

Download or read book Heat Pump Water Heater Technology Assessment Based on Laboratory Research and Energy Simulation Models written by and published by . This book was released on 2012 with total page 34 pages. Available in PDF, EPUB and Kindle. Book excerpt: This paper explores the laboratory performance of five integrated Heat Pump Water Heaters (HPWHs) across a wide range of operating conditions representative of US climate regions. Laboratory results demonstrate the efficiency of this technology under most of the conditions tested and show that differences in control schemes and design features impact the performance of the individual units. These results were used to understand current model limitations, and then to bracket the energy savings potential for HPWH technology in various US climate regions. Simulation results show that HPWHs are expected to provide significant energy savings in many climate zones when compared to other types of water heaters (up to 64%, including impact on HVAC systems).

NREL Tests Integrated Heat Pump Water Heater Performance in Different Climates (Fact Sheet).

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ISBN 13 :
Total Pages : 1 pages
Book Rating : 4.:/5 (873 download)

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Book Synopsis NREL Tests Integrated Heat Pump Water Heater Performance in Different Climates (Fact Sheet). by :

Download or read book NREL Tests Integrated Heat Pump Water Heater Performance in Different Climates (Fact Sheet). written by and published by . This book was released on 2012 with total page 1 pages. Available in PDF, EPUB and Kindle. Book excerpt: This technical highlight describes NREL tests to capture information about heat pump performance across a wide range of ambient conditions for five heat pump water heaters (HPWH). These water heaters have the potential to significantly reduce water heater energy use relative to traditional electric resistance water heaters. These tests have provided detailed performance data for these appliances, which have been used to evaluate the cost of saved energy as a function of climate. The performance of HPWHs is dependent on ambient air temperature and humidity and the logic controlling the heat pump and the backup resistance heaters. The laboratory tests were designed to measure each unit's performance across a range of air conditions and determine the specific logic controlling the two heat sources, which has a large effect on the comfort of the users and the energy efficiency of the system. Unlike other types of water heaters, HPWHs are both influenced by and have an effect on their surroundings. Since these effects are complex and different for virtually every house and climate region, creating an accurate HPWH model from the data gathered during the laboratory tests was a main goal of the project. Using the results from NREL's laboratory tests, such as the Coefficient of Performance (COP) curves for different air conditions as shown in Figure 1, an existing HPWH model is being modified to produce more accurate whole-house simulations. This will allow the interactions between the HPWH and the home's heating and cooling system to be evaluated in detail, for any climate region. Once these modeling capabilities are in place, a realistic cost-benefit analysis can be performed for a HPWH installation anywhere in the country. An accurate HPWH model will help to quantify the savings associated with installing a HPWH in the place of a standard electric water heater. In most locations, HPWHs are not yet a cost-effective alternative to natural gas water heaters. The detailed system performance maps that were developed by this testing program will be used to: (1) Target regions of the country that would benefit most from this technology; (2) Identify improvements in current systems to maximize homeowner cost savings; and (3) Explore opportunities for development of advanced hot water heating systems.

NEEA Heat Pump Water Heater Field Study Report

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ISBN 13 :
Total Pages : 56 pages
Book Rating : 4.:/5 (957 download)

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Book Synopsis NEEA Heat Pump Water Heater Field Study Report by : Fluid Market Strategies

Download or read book NEEA Heat Pump Water Heater Field Study Report written by Fluid Market Strategies and published by . This book was released on 2013 with total page 56 pages. Available in PDF, EPUB and Kindle. Book excerpt: "This report focuses on the detailed metering findings on 30 homes selected to evaluate the operation of Northern Climate Specification qualified Tier 2 Heat Pump Water Heaters (HPWHs). Overall in-field metering results suggest that units installed in conditioned spaces with warmer ambient air temperatures demonstrate higher Coefficient of Performance (COP) on average. Furthermore, the field study confirms that HPWHs are an efficient technology. Incorporating this information into future planning and program design efforts will help ensure future use of the technology"--Publisher's description (viewed August 19, 2016).