-
Experiment and Simulation Study on Silicon Oil Immersion Cooling Densely-Packed Solar Cells Under High Concentration Ratio
Xue Kang,
Yiping Wang,
Ganchao Xin,
Xusheng Shi
Issue:
Volume 5, Issue 3, June 2016
Pages:
90-96
Received:
16 May 2016
Published:
19 May 2016
Abstract: In order to solve the heat dissipation problem of densely-packed solar cells in high concentration photovoltaic (HCPV) system, a new cooling method of using silicon oil directly immerse the solar cells was proposed. The heat transfer performance of silicon oil immersion cooling the densely-packed solar cells with and without fin structure was investigated through experiment and simulation methods. The results of heat transfer performance of solar cells without fin structure showed that the simulated data was consistent well with data of experiment and the temperature could be lowered down in the operation range of solar cell. Furthermore, the heat transfer performance of solar cells with fin structure was researched using the model under different silicon oil inlet temperatures, inlet flow rates and the flow pressure drop was measured. The results indicated that the solar cells temperature declined and distributed well with silicon oil inlet flow rate increasing but the solar cells temperature raised linearly with silicon oil inlet temperature increasing. The optimized parameters of cooling receiver with fin structure were that: height of fin was 14 mm, number of fin was 50 and the thickness of substrate was 1.5 mm, with which the large amount of heat of densely-packed solar cells under high concentration ratio could be well controlled and make sure the power generation of HCPV system was high efficient.
Abstract: In order to solve the heat dissipation problem of densely-packed solar cells in high concentration photovoltaic (HCPV) system, a new cooling method of using silicon oil directly immerse the solar cells was proposed. The heat transfer performance of silicon oil immersion cooling the densely-packed solar cells with and without fin structure was inves...
Show More
-
Modelling and Analysis of Thermoelectric Generation of Materials Using Matlab/Simulink
K. P. V. B. Kobbekaduwa,
N. D. Subasinghe
Issue:
Volume 5, Issue 3, June 2016
Pages:
97-104
Received:
19 May 2016
Published:
19 May 2016
Abstract: This paper presents several models and implementations on measuring the thermoelectric behaviour of an unknown material using Matlab/Simulink. The proposed models are designed using Simulink block libraries and can be linked to data obtained from an actual experimental setup. This model is unique, as it also contains an implementation that can be used as a laboratory experiment to estimate the thermal conductivity of the unknown material thus, making it easy to use for simulation, analysis and efficiency optimization of novel thermoelectric material. The model was tested on a natural graphite sample with a maximum output voltage of 0.74mV at a temperature difference of 25.3K. Thus, according to the collected data, an experimental mean value of 68W/m.K was observed for the thermal conductivity while the Seebeck coefficient had a mean value of -3.1µV/K. Hence, it is apparent that this model would be ideal for thermoelectric experimentation in a laboratory based environment especially as a user interface for students.
Abstract: This paper presents several models and implementations on measuring the thermoelectric behaviour of an unknown material using Matlab/Simulink. The proposed models are designed using Simulink block libraries and can be linked to data obtained from an actual experimental setup. This model is unique, as it also contains an implementation that can be u...
Show More
-
Numerical Analysis of Integrated Phase Change Material in Solar Water Heating Systems
Samuel Sami,
Orlando Copado
Issue:
Volume 5, Issue 3, June 2016
Pages:
105-112
Received:
5 May 2016
Accepted:
26 May 2016
Published:
6 June 2016
Abstract: A mathematical model based upon the conservation and heat transfer equations has been developed to predict the thermal behavior of integrated phase change material in solar collector during thermal storage. The model includes fusion of the phase change material as well as sensible heat. The thermal behavior of the phase change material during charging and discharging have been studied numerically, and analyzed under different conditions. Comparisons were made against experimental data for validation of the predictive model. The model fairly predicted experimental data obtained at various inlet conditions.
Abstract: A mathematical model based upon the conservation and heat transfer equations has been developed to predict the thermal behavior of integrated phase change material in solar collector during thermal storage. The model includes fusion of the phase change material as well as sensible heat. The thermal behavior of the phase change material during charg...
Show More
-
Energy- and Indoor-Related Information for Office Occupants: What do They Really Want
Sami Karjalainen,
Janne Peltonen
Issue:
Volume 5, Issue 3, June 2016
Pages:
113-120
Received:
6 June 2016
Published:
7 June 2016
Abstract: A number of studies have shown that feedback on users’ own energy consumption can be effective in reducing household energy consumption. Almost all the studies on presenting energy feedback relate to in-home displays and domestic environments, only a few concern other contexts. Building automation systems in modern office buildings collect a large amount of energy- and indoor-related measurements. In this study, the primary interest lies in how energy- and indoor-related measurements could be used to increase energy awareness and occupant satisfaction. The purpose of this work is to study the preferences of office occupants and to find out what kind of information they are interested in. A questionnaire was delivered to two buildings in Finland. The total number of respondents was 151. The results show that the respondents were more interested in receiving indoor-related information than energy-related information. They were especially interested in knowing the room temperature in their own office. Almost half of them were not interested in energy-related information since they chose none of the energy-related options. The most effective ways to increase energy conservation in offices are discussed.
Abstract: A number of studies have shown that feedback on users’ own energy consumption can be effective in reducing household energy consumption. Almost all the studies on presenting energy feedback relate to in-home displays and domestic environments, only a few concern other contexts. Building automation systems in modern office buildings collect a large ...
Show More
-
Usage Patterns of Air Conditioning System for Typical Types of Occupants and Their Interactive Features in Residential Buildings – A Case Study in Hangzhou, China
Minyan Lu,
Shuqin Chen,
Fei Fang,
Hong Zhang,
Xiyong Zhang,
Yangyang Pan,
Peltonen Janne
Issue:
Volume 5, Issue 3, June 2016
Pages:
121-128
Received:
11 June 2016
Published:
12 June 2016
Abstract: The usage pattern related to air conditioning (AC) can significantly influence the energy consumption of residential buildings in HSCW zone. A survey, consisting of the general information about the household and building characteristics, occupant behavior of controlling AC and occupants’ reactions to others’ requirements, has been carried out in Hangzhou in order to develop the database of AC usage patterns in this district, analyze the characteristics of AC usage of typical types of occupants (including children and teenagers, youth, middle age and elder) and their interactive features. The survey results indicate that in contrast to the children and teenagers, the elders prefer a relatively high outdoor temperature to start using AC, as well as the setting temperature. Meanwhile, the majority of them use the AC for a shorter time compared to other three types of occupants. At the same time, youth and middle-aged people would like to use AC for a long time and maintain a medium temperature and. Besides, these four typical occupants have a similar attitude on the operating of AC when there is someone else in the same space. Over 75% of respondents take others’ feeling into consideration and share their opinions with their family members regarding turning on/off the AC and the setting temperature, which may change the operation patterns of AC.
Abstract: The usage pattern related to air conditioning (AC) can significantly influence the energy consumption of residential buildings in HSCW zone. A survey, consisting of the general information about the household and building characteristics, occupant behavior of controlling AC and occupants’ reactions to others’ requirements, has been carried out in H...
Show More
-
Non-intrusive Appliance Load Monitoring (NIALM) System with the Possibility for Users to Follow the Consumption of Individual Electricity Appliances from the Calendar
Issue:
Volume 5, Issue 3, June 2016
Pages:
129-132
Received:
11 June 2016
Published:
12 June 2016
Abstract: This paper presents a technical system, which uses the non-intrusive appliance load monitoring (NIALM) method. The solution enables the end user to observe the electricity consumption of the individual appliances. By dividing electricity consumption to individual appliances, it improves the users’ understanding of the overall energy use of the building. This way the owner of the building is able to intervene better with the energy consumption of the building. Observation of the electricity appliances is performed in a web application in a user interface calendar view.
Abstract: This paper presents a technical system, which uses the non-intrusive appliance load monitoring (NIALM) method. The solution enables the end user to observe the electricity consumption of the individual appliances. By dividing electricity consumption to individual appliances, it improves the users’ understanding of the overall energy use of the buil...
Show More
-
Techno-Economic Assessment of Installing a Reliable Renewable Energy System for Electric Power Generation at Koforidua Polytechnic
Isaac Kwasi Yankey,
Samuel Kwofie,
Godfred Kwame Abledu
Issue:
Volume 5, Issue 3, June 2016
Pages:
133-140
Received:
14 May 2016
Accepted:
28 May 2016
Published:
13 June 2016
Abstract: Ghana has been experiencing a lot of power outages over the years, mainly due to the heavy reliance on hydroelectric power plants, poor maintenance culture for existing plants as well as rising energy demand for development. These shortages have hindered the smooth running of businesses and academic institutions in the country. Institutions therefore operate with Genset for 12 hours with huge operational cost. This work therefore seeks to technically and economically assess a reliable alternative power supply for Koforidua Polytechnic. The building used in this assessment is the engineering block, which has five (5) floors with a total energy consumption of 227.520kWh/day for lights and fans. Homer software for micro grid and distributed generation power system design and optimization (NREL Homer) was used to do the optimization and sensitivity analysis with daily average electric demand of 9.48kW and peak power of 26.7kW with July, August and December having the highest mean values. The designed Photovoltaic (PV) system consists of 70kW monocrystalline PV modules of 250 Wp at a system voltage of 12V with 111 batteries and 17kW converter. The levelized Net Cost to install a renewable energy system (PV) divided by its expected time energy output of electricity from the optimized system at an annual real interest rate of ten (10%) percent is GHȻ2.38/kW. For the PV system designed to reach “Grid Parity”, the levelized cost of energy is estimated to be GHȻ2.03/kW with an annual real interest rate of six (6%) percent.
Abstract: Ghana has been experiencing a lot of power outages over the years, mainly due to the heavy reliance on hydroelectric power plants, poor maintenance culture for existing plants as well as rising energy demand for development. These shortages have hindered the smooth running of businesses and academic institutions in the country. Institutions therefo...
Show More
