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1 – 10 of 269Akbar Alidadi Shamsabadi, Mehdi Jahangiri, Tayebeh Rezaei, Rouhollah Yadollahi Farsani, Ali Seryani and Siavash Hakim
In this study, a solar water heating system along with a seasonal thermal energy storage and a heat pump is designed for a villa with an area of 192 m2 in Tehran, the capital of…
Abstract
Purpose
In this study, a solar water heating system along with a seasonal thermal energy storage and a heat pump is designed for a villa with an area of 192 m2 in Tehran, the capital of Iran.
Design/methodology/approach
According to the material and the area of the residential space, the required heating of the building was calculated manually and then the thermodynamic analysis of the system and simulation was done in MATLAB software. Finally, regarding the waste of system, an efficient solar heating system, providing all the required energy to heat the building, was obtained.
Findings
The surface area of the solar collector is equal to 46 m2, the capacity of the tank is about 2,850 m3, insulation thickness stands at 55 cm and the coefficient of performance in required heat pump is accounted to about 9.02. Also, according to the assessments, the maximum level of received energy by the collector in this system occurs at a maximum temperature of 68ºC.
Originality/value
To the best of the authors’ knowledge, in the present work, for the first time, using mathematical modeling and analyzing of the first and second laws of thermodynamics, as well as using of computational code in MATLAB software environment, the solar-assisted ground source heat pump system is simulated in a residential unit located in Tehran.
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The purpose of this paper is to describe how, in the recent attempts to stimulate alternative energy sources for heating and cooling of buildings, emphasis has been put on…
Abstract
Purpose
The purpose of this paper is to describe how, in the recent attempts to stimulate alternative energy sources for heating and cooling of buildings, emphasis has been put on utilisation of the ambient energy from ground source heat pump systems (GSHPs) and other renewable energy sources.
Design/methodology/approach
Exploitation of renewable energy sources and particularly ground heat in buildings can significantly contribute towards reducing dependency on fossil fuels. This paper highlights the potential energy saving that could be achieved through use of ground energy source. It also focuses on the optimisation and improvement of the operation conditions of the heat cycles and performances of the direct expansion (DX) GSHP.
Findings
It is concluded that the direct expansion of GSHP are extendable to more comprehensive applications combined with the ground heat exchanger in foundation piles and the seasonal thermal energy storage from solar thermal collectors.
Originality/value
The paper highlights the energy problem and the possible saving that can be achieved through the use of the GSHP systems and discusses the principle of the ground source energy, varieties of GSHPs, and various developments.
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Uroš Stritih, Halime Paksoy, Bekir Turgut, Eneja Osterman, Hunay Evliya and Vincenc Butala
Bilateral project with Slovenia and Turkey with the title thermal energy storage for efficient utilization of solar energy was the basis for this paper. The paper aims to discuss…
Abstract
Purpose
Bilateral project with Slovenia and Turkey with the title thermal energy storage for efficient utilization of solar energy was the basis for this paper. The paper aims to discuss this issue.
Design/methodology/approach
The paper is the review of solar thermal storage technologies with examples of use in Slovenia and Turkey.
Findings
The authors have found out that compact and cost effective thermal energy storage are essential.
Research limitations/implications
Research on the field of thermal energy storage in Slovenia and Turkey is presented.
Practical implications
The paper presents solar systems in Slovenia and Turkey.
Originality/value
The paper gives information about the sustainable energy future on the basis of solar energy.
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Åsa Grytli Tveten, Jon Gustav Kirkerud and Torjus Folsland Bolkesjø
This study aims to investigate the effects of thermal–hydro interconnection on the revenues, market value and curtailment of variable renewable energy (VRE). The increasing market…
Abstract
Purpose
This study aims to investigate the effects of thermal–hydro interconnection on the revenues, market value and curtailment of variable renewable energy (VRE). The increasing market shares of VRE sources in the Northern European power system cause declining revenues for VRE producers, because of the merit-order effect. A sparsely studied flexibility measure for mitigating the drop in the VRE market value is increased interconnection between thermal- and hydropower-dominated regions.
Design/methodology/approach
A comprehensive partial equilibrium model with a high spatial and temporal resolution is applied for the analysis.
Findings
Model simulation results for 2030 show that thermal–hydro interconnection will cause exchange patterns that to a larger extent follow VRE production patterns, causing significantly reduced VRE curtailment. Wind value factors are found to decrease in the hydropower-dominated regions and increase in thermal power-dominated regions. Because of increased average electricity prices in most regions, the revenues are, however, found to increase for all VRE technologies. By only assuming the planned increases in transmission capacity, total VRE revenues are found to increase by 3.3 per cent and VRE electricity generation increases by 3.7 TWh.
Originality/value
The current study is, to the authors' knowledge, the first to analyze the effect of interconnection between thermal- and hydropower-dominated regions on the VRE market value, and the authors conclude that this is a promising flexibility measure for mitigating the value-drop of VRE caused by the merit-order effect. The study results demonstrate the importance of taking the whole power system into consideration when planning future transmission capacity expansions.
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Esteban Zalamea León, Rodrigo García Alvarado, Reinaldo Sánchez Arriagada and Sergio Baeriswy
The roofs of houses located at middle latitudes receive significant solar radiation useful to supply their own energy demands and to feed back into the urban electricity network…
Abstract
The roofs of houses located at middle latitudes receive significant solar radiation useful to supply their own energy demands and to feed back into the urban electricity network. However, solar panels should be properly integrated into roofs. This study analyzed roof geometry and integrated solar performance of Photovoltaic, thermal-photovoltaic, and hybrid solar collection technologies on dwelling cases selected from a sample of recent housing developments in Concepción, Chile. Hour-by-hour energy generation estimates and comparisons with demand levels were calculated for representative days during seasons of maximum, minimum as well as mid-season. These estimates took into account the roof tilt and orientation effects also. Trnsys@ software was used to determine electricity supply and F-Chart tool for thermal energy supply. The results show five times more panels can be placed on the largest and most regular shaped roof sections than on those with the smallest and most irregular shapes. The house model with the largest roof section can provide up to six times more energy than the model with the smallest second roof section in different seasons and systems. This paper thus provides new findings on the performance of solar technologies when related to home energy demands and roof geometry.
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Roy Botman and Jos van Schijndel
The purpose of this paper is to present a tool for simulating heat sharing opportunities between multiple buildings.
Abstract
Purpose
The purpose of this paper is to present a tool for simulating heat sharing opportunities between multiple buildings.
Design/methodology/approach
The approach is based on a building simulation model, HAMBase, in combination with an analytical programming code using MatLab.
Findings
The tool provides a quick insight in possibilities for district heat sharing. It is able to operate without using too many parameters. From the results, it can be derived that storage tanks provide a great advantage in performance over the direct heat demand and supply method.
Research limitations/implications
The main limitations are as follows: the used models are based on assumptions plus values derived from literature and a verification that is based on energy balance rules; and the MatLab code is verified by checking for possible errors, but is not completely validated.
Originality/value
The main value of the work is that the presented methodology behind the tool is generally applicable and implementable in other models.
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Stephen Loh Tangwe, Michael Simon and Edson L. Meyer
This paper aims to show that by using air source heat pump (ASHP) water heater in the residential sector, the energy consumption from sanitary hot water production can be reduced…
Abstract
Purpose
This paper aims to show that by using air source heat pump (ASHP) water heater in the residential sector, the energy consumption from sanitary hot water production can be reduced by more than 50 per cent. Hence, this study quantitatively and qualitatively confirms that domestic ASHP water heater is a renewable and energy efficient device for sanitary hot water production.
Design/methodology/approach
Design and building of a data acquisition system comprises a data logger, power meters, flow meters, temperature sensors, ambient and relative humidity sensor and an electronic input pulse adapter to monitor the ASHP water heater performance. All the sensors are accommodated by the U30-NRC data logger. The temperature sensors are installed on the inlet pipe containing a flow meter and the outlet pipe of the ASHP unit, the vicinity of both evaporator and expel cold air. An additional temperature sensor and a flow meter that cater for hot water drawn off measurements are incorporated into the data acquisition system (DAS).
Findings
The result from a specific monitoring split type ASHP water heater gives an average daily coefficient of performance (COP) of 2.36 and the total electrical energy of 4.15 kWh, and volume of hot water drawn off was 273 L. These results were influenced by ambient temperature and relative humidity.
Research limitations/implications
The cost involved in purchasing the entire sensors and data logger limits the number and categories of ASHP water heaters whose performance were going to be monitored. Pressure sensors were excluded in the data acquisition system.
Practical implications
The data acquisition system can easily be designed and the logger can also be easily programed. Hence, no high technical or computer skills are needed to install the DAS and to be able to read out the results.
Social implications
Hence, the data acquisition system can be installed on the entire domestic Eskom roll out air source heat pump water heaters to effectively determine the coefficient of performance and demand reductions.
Originality/value
This DAS is the first of its kind to be built in South Africa to be used to determine the performance of an ASHP water heater with high accuracy and precision. DAS is also robust.
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Anna Wieprzkowicz and Dariusz Heim
The purpose of this paper is to investigate energy performance of thermal insulation modified by phase change materials (PCM). Special attention was paid to the problem of proper…
Abstract
Purpose
The purpose of this paper is to investigate energy performance of thermal insulation modified by phase change materials (PCM). Special attention was paid to the problem of proper performance assessment of such components by computational techniques and methods of its evaluation.
Design/methodology/approach
Analysis was conducted on the basis of the results obtained using the dynamic building simulation technique performed by ESP-r software. Two cases of insulation components enhanced by a layer: characterised by increased latent heat capacity were analysed and compared. Results were investigated in terms of thermal comfort and energy efficiency, using evaluation methods from literature and new, original indicators proposed by authors.
Findings
The analysis revealed that performance of insulation enhanced by PCM is very dynamic and highly sensitive to changeable weather conditions. Thus, there is a strong need for the development of the assessment methods and guidelines for the performance of such components with changeable physical properties.
Practical implications
The methodology and the results reported in this paper could be used as a guideline for further parametric studies and optimisation tasks. Further development of phase change insulation can substantially change the existing approach to the building energy performance.
Originality/value
The paper introduces a new approach of the assessment of insulation components modified by PCM and highlights the dynamic characteristics of its performance.
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Colin D. A. Porteous and Rosalie Menon
Taking its cue from the UK government's declaration that every new home should be ‘zero-carbon’ by 2016, this paper explores how close a flexible, prototype-housing model might…
Abstract
Taking its cue from the UK government's declaration that every new home should be ‘zero-carbon’ by 2016, this paper explores how close a flexible, prototype-housing model might come to meeting this target (accepting that there is currently some ambiguity between the respective official ‘zero-carbon’ definitions regarding off-site renewable supply). The prime aim is to design economically (affordable by housing associations) to the European ‘passive house’ standard of no more than 15 kWh/m2 for space heating and a maximum total consumption of 70 kWh/m2 adding in hot water and electricity. The model also prioritizes generous access to sunlight and daylight, as well as realistic levels of air change in a low-volume, intensively occupied scenario. Associated aims are: a) to meet thermal loads without use of fossil fuels such as gas or oil; and b) to employ architecturally integrated active solar thermal and electrical arrays to respectively meet at least one third of the water heating and electrical loads. Micro-wind generation is excluded from the study as too site-dependent. A subsidiary agenda is to achieve a flexible plan in terms of orientation and access, and to provide utility facilities that support the environmental strategy (e.g. drying clothes without compromising energy use or air quality). The paper goes on to address equivalent prospects for retrofit, briefly discusses institutional and other barriers to achievement, and muses on how much of the balance of the electrical demand can be met renewably in Scotland in the near future.
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