scholarly journals Modeling and Simulation Performance Evaluation of a Proposed Calorimeter for Testing a Heat Pump System

Energies ◽  
2019 ◽  
Vol 12 (23) ◽  
pp. 4589 ◽  
Author(s):  
Amoabeng ◽  
Lee ◽  
Choi

The energy consumption for heating and cooling in the building sector accounts for more than one-third of total energy used worldwide. In view of that, it is important to develop energy efficient cooling and heating systems in order to conserve energy in buildings as well as reduce greenhouse gas emissions. In both commercial and residential buildings, the heat pump has been adopted as an energy efficient technology for space heating and cooling purposes as compared to conventional air conditioning systems. However, heat pumps undergo standard testing, rating, and certification procedures to ascertain their system performance. Essentially, the calorimeter for testing heat pumps has two test chambers to serve as a heat source and heat sink to control and maintain the test conditions required to simulate the heat pump indoor and outdoor units, simultaneously. In air-to-air heat pump units, the conventional calorimeter controls the air temperature and humidity conditions in each test chamber with separate air handling units consisting of a refrigerator, heater, humidifier, and supply fan, which results in high energy consumption. In this study, using dynamic modeling and simulation, a new calorimeter for controlling air conditions in each test chamber is proposed. The performance analysis based on simulation results showed that the newly proposed calorimeter predicted at least 43% energy savings with the use of a heat recovery unit and small refrigerator capacity as compared to the conventional calorimeter that utilized a large refrigerator capacity for all the weather conditions and load capacities that we investigated.

HortScience ◽  
1994 ◽  
Vol 29 (4) ◽  
pp. 249a-249
Author(s):  
Eric A. Lavoie ◽  
Damien de Halleux ◽  
André Gosselin ◽  
Jean-Claude Dufour

The main objective of this research was to produce a simulated model that permitted the evaluation of operating costs of commercial greenhouse tomato growers with respect to heating methods (hot air, hot water, radiant and heat pumps) and the use of artificial lighting for 1991 and 1992. This research showed that the main factors that negatively influence profitability were energy consumption during cold periods and the price of tomatoes during the summer season. The conventional hot water system consumed less energy than the heat pump system and produced marketable fruit yields similar to those from the heat pump system. The hot water system was generally more profitable in regards to energy consumption and productivity. Moreover, investment costs were less; therefore, this system gives best overall financial savings. As for radiant and hot air systems, their overall financial status falls between that of the hot water system and the heat pump. The radiant system proved to be more energy efficient that the hot air system, but the latter produced a higher marketable fruit yield over the 2-year study.


2020 ◽  
Vol 216 ◽  
pp. 01125
Author(s):  
Mexriya Koroly ◽  
Anvar Anarbaev ◽  
Alisher Usmanov ◽  
Kuvondyk Soliev

In this paper, there is analyzed the results of exergy economic optimization of heat-cooling supply in building by using the solar heat pump system. It is possible to realize a system having high reliability in operation of the system. The solar heat pump system according to the present technical decision has high energy efficiency while ensuring reliability, and is useful as a domestic air conditioning and heating water heater. It can also be applied to uses such as industrial heating and cooling devices.


Energies ◽  
2019 ◽  
Vol 12 (13) ◽  
pp. 2496 ◽  
Author(s):  
Laura Carnieletto ◽  
Borja Badenes ◽  
Marco Belliardi ◽  
Adriana Bernardi ◽  
Samantha Graci ◽  
...  

The design of ground source heat pumps is a fundamental step to ensure the high energy efficiency of heat pump systems throughout their operating years. To enhance the diffusion of ground source heat pump systems, two different tools are developed in the H2020 research project named, “Cheap GSHPs”: A design tool and a decision support system. In both cases, the energy demand of the buildings may not be calculated by the user. The main input data, to evaluate the size of the borehole heat exchangers, is the building energy demand. This paper presents a methodology to correlate energy demand, building typologies, and climatic conditions for different types of residential buildings. Rather than envelope properties, three insulation levels have been considered in different climatic conditions to set up a database of energy profiles. Analyzing European climatic test reference years, 23 locations have been considered. For each location, the overall energy and the mean hourly monthly energy profiles for heating and cooling have been calculated. Pre-calculated profiles are needed to size generation systems and, in particular, ground source heat pumps. For this reason, correlations based on the degree days for heating and cooling demand have been found in order to generalize the results for different buildings. These correlations depend on the Köppen–Geiger climate scale.


Author(s):  
Jenny Chu ◽  
Cynthia A. Cruickshank

Heat pumps are commonly used for space-heating and cooling requirements. The combination of solar thermal and heat pump systems as a single solar-assisted heat pump (SAHP) system is a promising technology for offsetting domestic hot water, space-heating and cooling loads more efficiently. Task 44 of the Solar Heating and Cooling Programme of the International Energy Agency is currently investigating ways to optimize SAHP systems for residential use. This paper presents a review of past and current work conducted on SAHP systems. Specifically, the key performance data from many studies are highlighted and different system configurations are compared in order to establish insight towards which system configurations are suitable for the Canadian residential sector. It was found that the most suitable configuration for Canadian residential buildings depend on a combination of factors which may include occupant behavior, building characteristics, operation parameters, system components, the performance criteria of interest and climate. A large variety of configurations and parameters exist for SAHP systems and this made analyzing a specific system, comparing differing systems and establishing an optimal design fairly difficult. It was found that different authors used various different performance criterions and this inconsistency also added to the difficulty of comparing the studies of different systems. Overall, a standard performance criterion needs to be established for SAHP systems in order to meaningfully compare different configurations and determine optimal configurations for certain requirements.


2021 ◽  
Author(s):  
Maudud Hassan Quazi

This objective of this project is to determine the energy and environmental potential of distributed common loop water source heat pump system in a near or net-zero commercial office building, which has simultaneous heating and cooling load in winter and shoulder seasons. It is expected that the perimeter zones will have heating demand during those months, while the core zones will have consistent cooling demand throughout the year. The motive is to reclaim the rejected heat from the cooling operation and transfer it to the zones requiring heating. The building under study is a 60,000 ft2 three storey commercial office building, which has private offices along the perimeter, and open work area in the core. In the first part of the analysis, the base building has been modelled and simulated to the minimum requirements of ASHRAE 90.1-Energy Standard for Buildings except Low-Rise Residential Buildings using simulation software eQuest 3.65. The Heating Ventilation and Airconditioning (HVAC) system used is four-pipe fan coil system serving individual zones. The fan coil units use a centralized natural gas boiler and a variable capacity centrifugal chiller as external source of heating and cooling respectively. The base case consumes a total of 524.54 x 1000 kWh of electricity and 1,056 million Btu of natural gas annually. The second part is the modelling and simulation of a proposed case, which uses the same building envelope, occupancy, lighting and equipment as the base case. The HVAC system used is a distributed common loop heat pump system connected to a cooling tower for heat rejection, and a condensing boiler for heat addition. During the occupied hours, when simultaneous cooling and heating loads exist in the building, the cooling zone heat pumps rejects exhaust heat into the common loop, and the heat is subsequently used by the heat pumps operating in heating mode. Using this method, the heat pump system reduces its dependence on the cooling tower and the boiler, which only operate to maintain the loop temperature in an acceptable range. There is 9,510 kWh (1.81%) increase in electricity consumption by proposed case comparing to the base building. Natural gas consumption has been reduced by 353.65 million Btu (33.48%). Annual utility bill has increased by $1,483.00 which is 1.88% higher than the base case. 15.7 tonnes of greenhouse gas can be reduced if the proposed case is adopted.


2021 ◽  
Vol 65 (1) ◽  
pp. 83-92
Author(s):  
Valeria Todeschi ◽  
Simone Beltramino ◽  
Bernadette El Jamous ◽  
Guglielmina Mutani

Nowadays, energy consumption in buildings is one of the fundamental drivers to control greenhouse gas emissions and environmental impact. In fact, the air quality of urban environments can cause two main phenomena in metropolitan areas: urban heat island and climate changes. The aim of this work is to showcase how different building variables can impact the residential building’s space heating and cooling energy consumption. Buildings energy-related variables can be fundamental viewpoints to improve the energy performance of neighborhoods, especially in future urban planning. This work examines four neighborhoods in the city of Turin (IT): Arquata, Crocetta, Sacchi, and Olympic Village characterized by different morphologies and building typologies. In each neighborhood, residential building was grouped according to orientations and construction periods. A sensitivity analysis was applied by analysing six building variables: infiltration rate, window-to-wall ratio, and windows, walls, roofs, and floor thermal transmittances. The energy consumption for space heating and cooling of residential buildings and local climate conditions were investigated using CitySim Pro tool and ENVI-met. The challenge of this work is to identify the building variables that most influence energy consumption and to understand how to promote high-energy efficiency neighborhoods: the goal is to identify the “ideal” urban form with low consumption and good comfort conditions in outdoor urban environments. The results of this work show a significant connection between the energy consumption and the six analyzed building variables; however, this relationship also depends on the shape and orientation of the neighborhood.


Buildings ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 356
Author(s):  
Fujen Wang ◽  
Kusnandar ◽  
Hungwen Lin ◽  
Minghua Tsai

With the cost of energy rising, the value of conservation grows. Interest in energy efficiency could be a sound investment or a necessary public policy. Heat pump systems provide economical alternatives of recovering heat from different sources for use in various applications. The objective of this study is to present the strategic approach on the energy efficient analysis of the water heating system retrofitted by applying a heat pump system in the dormitory of a university. Energy savings were determined by comparing field measurements of water consumption, water temperature and power consumption of the overall system before (electric resistance heating system) and after (heat pump heating system) the implementation of this project. Furthermore, the building energy simulation code (eQuest) has been applied to verify and predict the long-term energy consumption for both water heating systems. The results from energy modelling revealed the good agreement for energy simulation and field measurement data and the improvement of energy efficiency and energy savings could be achieved satisfactorily by retrofitting of a heat pump system. The energy conversion efficiency of hot water for energy consumption at 0.63 (Mcal/Mcal) could be achieved after the application of heat pump water heating system. It also presented the annual saving about USD 20,000 (NTD 600,000) for the dorm by using a heat pump heating system under the electrical billing rate of Taiwan.


2021 ◽  
Vol 246 ◽  
pp. 06009
Author(s):  
Janne Hirvonen ◽  
Juha Jokisalo ◽  
Risto Kosonen

Most Finnish residential buildings have been built before ventilation heat recovery options became mandatory. Exhaust air heat pumps are an effective way to reduce emissions, but they cannot cover all heating demand. Ground-source heat pumps can be designed to meet all loads, but they require corresponding amounts of space both above and below ground. This simulation study combines residential ventilation and sewage waste heat with a ground-source heat pump system to improve system sustainability and cost-effectiveness. A hybrid waste heat and ground-source heat pump system was shown to have 20% lower life cycle costs compared to a pure ground-source heat pump system. It also maintained sustainable ground temperature levels over the long term, while reducing above-ground space requirements by 95%.


2021 ◽  
Author(s):  
Maudud Hassan Quazi

This objective of this project is to determine the energy and environmental potential of distributed common loop water source heat pump system in a near or net-zero commercial office building, which has simultaneous heating and cooling load in winter and shoulder seasons. It is expected that the perimeter zones will have heating demand during those months, while the core zones will have consistent cooling demand throughout the year. The motive is to reclaim the rejected heat from the cooling operation and transfer it to the zones requiring heating. The building under study is a 60,000 ft2 three storey commercial office building, which has private offices along the perimeter, and open work area in the core. In the first part of the analysis, the base building has been modelled and simulated to the minimum requirements of ASHRAE 90.1-Energy Standard for Buildings except Low-Rise Residential Buildings using simulation software eQuest 3.65. The Heating Ventilation and Airconditioning (HVAC) system used is four-pipe fan coil system serving individual zones. The fan coil units use a centralized natural gas boiler and a variable capacity centrifugal chiller as external source of heating and cooling respectively. The base case consumes a total of 524.54 x 1000 kWh of electricity and 1,056 million Btu of natural gas annually. The second part is the modelling and simulation of a proposed case, which uses the same building envelope, occupancy, lighting and equipment as the base case. The HVAC system used is a distributed common loop heat pump system connected to a cooling tower for heat rejection, and a condensing boiler for heat addition. During the occupied hours, when simultaneous cooling and heating loads exist in the building, the cooling zone heat pumps rejects exhaust heat into the common loop, and the heat is subsequently used by the heat pumps operating in heating mode. Using this method, the heat pump system reduces its dependence on the cooling tower and the boiler, which only operate to maintain the loop temperature in an acceptable range. There is 9,510 kWh (1.81%) increase in electricity consumption by proposed case comparing to the base building. Natural gas consumption has been reduced by 353.65 million Btu (33.48%). Annual utility bill has increased by $1,483.00 which is 1.88% higher than the base case. 15.7 tonnes of greenhouse gas can be reduced if the proposed case is adopted.


Author(s):  
Shui Yuan ◽  
Michel Grabon

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.


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