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Building renewable energy and thermal energy storage system 2018

A special issue of Energies (ISSN 1996-1073). This special issue belongs to the section "A: Sustainable Energy".

Deadline for manuscript submissions: closed (20 October 2018) | Viewed by 46535

Special Issue Editors


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Guest Editor
School of Mechanical Engineering, Southwest Jiaotong University, Chengdu 610031, China
Interests: built environment for underground space; phase change materials; heat and mass transfer; solar thermal and power generation; heat pumps; refrigeration; air conditioning
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Guest Editor
1. Centre for Sustainable Energy Technologies, Energy and Environment Institute, University of Hull, Hull HU6 7RX, UK
2. Center of Intelligent Acoustics and Immersive Communications, Northwestern Polytechnical University, 127 Youyi West Road, Xi’an 710072, China
Interests: solar thermal and power technologies and systems; PV/thermal; heating; cooling; energy efficiency; heat and mass transfer
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Owing to the continuously growing energy demands in buildings, the renewable energy applied in buildings, and related research, have attracted more and more public attention. Currently, buildings consume one third of the total energy supply in developed countries and one quarter in developing countries. Both reducing building energy demands and effectively utilizing renewable energy in buildings are considered to be principal routes towards low energy and sustainable buildings. Due to the instability of the renewable energy supply, thermal energy storage technologies are also crucial to the widespread application of renewable energy in buildings.

As one of the most important renewable energy, solar energy technologies have been investigated for many years. Solar thermal (ST) technology, solar photovoltaic (PV) technology and Photovoltaic/thermal (PV/T) technology are regarded as the most feasible renewable solutions for building applications. ST technology, which is the most mature technology among all currently available solar energy technologies, has a much higher solar conversion efficiency and shorter payback time. Although, currently, PV installations in buildings are still small-scale, PV technology has already developed into a mature technology, both technically and commercially. With continuously technical advances, reduced costs and legal policies in renewable energies, the applications of PV technology will continue to grow quickly and will eventually become an important electrical energy supplier in the world. PV/T technology, which can simultaneously generate electricity and heat, takes advantages of both PV and solar thermal technologies. Due to its higher overall solar conversion efficiency and more effective use of space, the market potential of PV/T technology is expected to be higher than individual PV and solar thermal technologies.

Ground coupled heat pump (GCHP) technology has been increasingly attracting attentions as a renewable energy technology of high energy efficiency and its environmentally-friendly mechanism for space cooling and heating. The most important component of the GCHP system is the ground heat exchangers (GHEs). Compared to other types of GHEs, vertical GHEs have more benefits, such as the smaller space taken for installation and superior energy efficiency. Heat transfer analysis of vertical GHEs has always been a key issue in designing GCHP systems. In addition, another key issue for GCHP systems is that the heat rejected into the ground is usually not equal to that absorbed from the ground, which will cause heat accumulation or heat attenuation in the ground. One of the cost-effective solutions is to promote GSHP systems in so-called hybrid GSHP systems. The design and applications of hybrid GSHP systems have become a special interest in the research of GCHP technologies.

Thermal energy storage (TES) technologies, including seasonal and short-term storage technologies, are considered to be important means to solve the problems of instability in renewable energy supply and the mismatching between building energy demands and a renewable energy supply. Phase change materials (PCMs), which are widely used in various thermal energy storage systems, are particularly attractive materials due to their high energy storage densities and stable phase change temperatures. However, research work is required to improve the thermal properties of PCMs, such as low thermal conductivity and high super-cooling degree, to increase the overall heat transfer efficiency. Furthermore, investigation of new PCM materials is very important for the development of effective latent thermal storage. Additionally, good design and control strategies for PCM units are crucially important for promoting the applications of PCMs in thermal storage energy systems.

We invite researchers to contribute original research articles, as well as review articles. Your contributions will promote public understanding of the operational principles of various building-applicable renewable energy technologies and thermal energy storage systems. We are particularly interested in articles presenting novel materials, new method and theories, or innovative aspects in practical applications that can help to enhance the efficiency and reduce the costs of building renewable energy and latent heat thermal storage systems. Potential topics include, but are not limited to:

  • Solar thermal systems: Domestic hot water, space heating and cooling
  • Photovoltaic and building integrated photovoltaic (BIPV) technologies
  • Photovoltaic/Thermal technologies
  • Heat transfer of GHEs
  • Design and operation strategy of hybrid GSHP
  • Heat transfer in PCMs and enhancement techniques
  • Characterization and development of new PCMs
  • Thermal energy storage systems in buildings
  • Thermal management system using PCMs
  • Integration methods and application of building renewable energy and heat storage system in buildings

Prof. Dr. Yanping Yuan
Prof. Dr. Xudong Zhao
Guest Editors

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Keywords

  • renewable energy
  • ground source heat pump
  • solar thermal
  • solar power
  • PV
  • PV/T
  • heat storage
  • latent heat
  • thermal management
  • PCMs
  • integration
  • building

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Published Papers (11 papers)

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Research

17 pages, 1537 KiB  
Article
An Efficient Energy Management Approach Using Fog-as-a-Service for Sharing Economy in a Smart Grid
by Adia Khalid, Sheraz Aslam, Khursheed Aurangzeb, Syed Irtaza Haider, Mahmood Ashraf and Nadeem Javaid
Energies 2018, 11(12), 3500; https://doi.org/10.3390/en11123500 - 14 Dec 2018
Cited by 37 | Viewed by 4379
Abstract
An unprecedented opportunity is presented by smart grid technologies to shift the energy industry into the new era of availability, reliability and efficiency that will contribute to our economic and environmental health. Renewable energy sources play a significant role in making environments greener [...] Read more.
An unprecedented opportunity is presented by smart grid technologies to shift the energy industry into the new era of availability, reliability and efficiency that will contribute to our economic and environmental health. Renewable energy sources play a significant role in making environments greener and generating electricity at a cheaper cost. The cloud/fog computing also contributes to tackling the computationally intensive tasks in a smart grid. This work proposes an energy efficient approach to solve the energy management problem in the fog based environment. We consider a small community that consists of multiple smart homes. A microgrid is installed at each residence for electricity generation. Moreover, it is connected with the fog server to share and store information. Smart energy consumers are able to share the details of excess energy with each other through the fog server. The proposed approach is validated through simulations in terms of cost and imported electricity alleviation. Full article
(This article belongs to the Special Issue Building renewable energy and thermal energy storage system 2018)
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25 pages, 4285 KiB  
Article
Financing the Renovation of the Cypriot Building Stock: An Assessment of the Energy Saving Potential of Different Policy Scenarios Based on the Invert/EE-Lab Model
by Marina Economidou, Paolo Zangheri, Andreas Müller and Lukas Kranzl
Energies 2018, 11(11), 3071; https://doi.org/10.3390/en11113071 - 7 Nov 2018
Cited by 10 | Viewed by 3720
Abstract
Despite various government policies promoting energy efficiency in buildings over the last 15 years, Cyprus is still associated with a large untapped energy efficiency potential in this sector. The impact of different policy scenarios on future energy needs of the building sector in [...] Read more.
Despite various government policies promoting energy efficiency in buildings over the last 15 years, Cyprus is still associated with a large untapped energy efficiency potential in this sector. The impact of different policy scenarios on future energy needs of the building sector in Cyprus is explored by first reviewing the current status of the building stock in Cyprus and existing national landscape of energy efficiency policies. Various new policies are then proposed to complement the existing framework and help exploit further the potential. Using the Invert/EE-Lab model, three policy scenarios extending to 2050 are assessed with the aim to estimate the energy efficiency potential of the Cypriot building sector and identify policy solutions to harness this potential. The energy consumed for heating, cooling, hot water, and lighting in the entire Cypriot building stock is expected to drop by up to 16% in 2050 compared to the baseline scenario. Under the most ambitious scenario, nearly 60% of the building stock in 2050 will be energy efficient, consuming less than half of the energy used by the average building stock in 2012. Taking into account the modelling results, recommendations on how to improve the financial landscape in buildings until 2050 are presented. Full article
(This article belongs to the Special Issue Building renewable energy and thermal energy storage system 2018)
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17 pages, 3057 KiB  
Article
Monitoring Data Study of the Performance of Renewable Energy Systems in a Near Zero Energy Building in Spain: A Case Study
by Javier M. Rey-Hernández, Eloy Velasco-Gómez, Julio F. San José-Alonso, Ana Tejero-González, Sergio L. González-González and Francisco J. Rey-Martínez
Energies 2018, 11(11), 2979; https://doi.org/10.3390/en11112979 - 1 Nov 2018
Cited by 18 | Viewed by 4281
Abstract
The building sector is responsible for a substantial part of the energy consumption and corresponding CO2 emissions. The European Union has consequently developed various directives, among which the updated Energy Performance of Buildings Directive 2018/844/EU stands out, aiming at minimizing the energy [...] Read more.
The building sector is responsible for a substantial part of the energy consumption and corresponding CO2 emissions. The European Union has consequently developed various directives, among which the updated Energy Performance of Buildings Directive 2018/844/EU stands out, aiming at minimizing the energy demand in buildings, improving the energy efficiency of their facilities and integrating renewable energies. The objective of the present study was to develop an analysis on the energy performance, related CO2 emissions and operating costs of the renewable energy technologies implemented within a multipurpose near Zero Energy Building (nZEB). The target building is an existing nZEB called LUCIA, located in Valladolid (Spain). Monitoring data provides the required information on the actual needs for electricity, cooling and heating. It is equipped with solar energy photovoltaic systems, a biomass boiler and a geothermal Earth to Air Heat Exchanger (EAHX) intended for meeting the ventilation thermal loads. All systems studied show favourable performances, but depend significantly on the particular characteristics of the building, the control algorithm and the climate of the location. Hence, design of these strategies for new nZEBs must consider all these factors. The combined use of the PhotoVoltaic PV System, the biomass and the EAHX reduces the CO2 emissions up to 123 to 170 tons/year in comparison with other fuels, entailing economic savings from the system operation of up to 43,000–50,000 €/year. Full article
(This article belongs to the Special Issue Building renewable energy and thermal energy storage system 2018)
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32 pages, 12812 KiB  
Article
Healthy Climate and Energy Savings: Using Thermal Ceramic Panels and Solar Thermal Panels in Mediterranean Housing Blocks
by Víctor Echarri-Iribarren, Carlos Rizo-Maestre and Fernando Echarri-Iribarren
Energies 2018, 11(10), 2707; https://doi.org/10.3390/en11102707 - 11 Oct 2018
Cited by 11 | Viewed by 4110
Abstract
Radiant surface conditioning systems based on capillary tube mats not only provide high standards of comfort, but they also generate substantial energy savings. These systems allow for using renewable energies such as solar thermal panels because they function with water at moderate temperatures—lower [...] Read more.
Radiant surface conditioning systems based on capillary tube mats not only provide high standards of comfort, but they also generate substantial energy savings. These systems allow for using renewable energies such as solar thermal panels because they function with water at moderate temperatures—lower in winter and higher in summer—compared to fan-coil systems or hot water radiator systems. Moreover, in summer, they can be combined with solar cooling systems based on lithium chloride or absorption systems based on lithium bromide, which enable the cooling of water at 15–16 °C by means of solar thermal panel energy collection. This further reduces the annual energy. The purpose of this study was to examine the application of thermal ceramic panels (TCP) containing prolipropylen (PPR) capillary tube mats, in residential buildings in the Spanish Mediterranean. The water distribution system was set up individually from a heat pump and was combined with a community system of solar thermal panels. After monitoring a home over a complete one-year cycle, the annual energy demand was quantified through simulations, based on both the radiant system and the VRV system, as well as in combination with a thermal solar panel system. TCP panels reduced the annual energy demands by 31.48%, and the additional investment cost of €11,497 could be amortized over 23.31 years. The combination of TCP panels with 18.5 m2 of solar thermal panels reduced the annual energy demand by 69.47%, and the investment of €20,534 of additional cost could be amortized over 15.67 years. The energy consumptions of installation elements were also comparatively quantified. Full article
(This article belongs to the Special Issue Building renewable energy and thermal energy storage system 2018)
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14 pages, 3320 KiB  
Article
Thermal Performance of Dwellings with Rooftop PV Panels and PV/Thermal Collectors
by Saad Odeh
Energies 2018, 11(7), 1879; https://doi.org/10.3390/en11071879 - 19 Jul 2018
Cited by 14 | Viewed by 4338
Abstract
To improve the energy efficiency of dwellings, rooftop photovoltaic (PV) technology is proposed in contemporary designs; however, adopting this technology will add a new component to the roof that may affect its thermal balance. This paper studies the effect of roof shading developed [...] Read more.
To improve the energy efficiency of dwellings, rooftop photovoltaic (PV) technology is proposed in contemporary designs; however, adopting this technology will add a new component to the roof that may affect its thermal balance. This paper studies the effect of roof shading developed by solar PV panels on dwellings’ thermal performance. The analysis in this work is performed by using two types of software packages: “AccuRate Sustainability” for rating the energy efficiency of a residential building design, and “PVSYST” for the solar PV power system design. AccuRate Sustainability is used to calculate the annual heating and cooling load, and PVSYST is used to evaluate the power production from the rooftop PV system. The analysis correlates the electrical energy generated from the PV panels to the change in the heating and cooling load due to roof shading. Different roof orientations, roof inclinations, and roof insulation, as well as PV dwelling floor areas, are considered in this study. The analysis shows that the drop in energy efficiency due to the shaded area of the roof by PV panels is very small compared to the energy generated by these panels. The analysis also shows that, with an increasing number of floors in the dwelling, the effect of shading by PV panels on thermal performance becomes negligible. The results show that insensitivity of the annual heating and cooling load to the thermal resistance of rooftop solar systems is only because the total thermal resistance is dominated by roof insulation. Full article
(This article belongs to the Special Issue Building renewable energy and thermal energy storage system 2018)
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14 pages, 6990 KiB  
Article
Experimental Assessment of the Energy Performance of a Double-Skin Semi-Transparent PV Window in the Hot-Summer and Cold-Winter Zone of China
by Wei Wang, Wei Zhang, Lingzhi Xie, Yupeng Wu, Hao Tian and Lin Zheng
Energies 2018, 11(7), 1700; https://doi.org/10.3390/en11071700 - 1 Jul 2018
Cited by 10 | Viewed by 3015
Abstract
The energy performance of the semi-transparent PV (STPV) window was carried out in a hot-summer and cold-winter zone of China. Semi-transparent PV (STPV) windows generate electric, reduce the heating load and aim to utilize daylighting efficiently. In order to analyze the energy performance [...] Read more.
The energy performance of the semi-transparent PV (STPV) window was carried out in a hot-summer and cold-winter zone of China. Semi-transparent PV (STPV) windows generate electric, reduce the heating load and aim to utilize daylighting efficiently. In order to analyze the energy performance of semi-transparent windows, a comparison test rig was set up which includes two test rooms of the same size. One room was installed with the STPV window and the other with a conventional window. The lighting, thermal, and electrical performance of STPV window was tested and compared with those of conventional window in the same ambient environment. It was observed that the maximum power generation of the STPV (a-SiGe) window was 33.3 W/m2 on a typical sunny day. Compared with the conventional windows, the average solar heat gain (SHGC) and Uvalue of STPV windows were 0.15 and 1.6, respectively, which is better than those of conventional window. On a sunny day, the Useful Daylighting Illuminance (UDI) of the test room was up to 52.2% better than the UDI of the conventional room. The results could support the application of photovoltaic technology in buildings in Southwest China. Full article
(This article belongs to the Special Issue Building renewable energy and thermal energy storage system 2018)
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19 pages, 9274 KiB  
Article
Heat and Mass Transfer Behavior Prediction and Thermal Performance Analysis of Earth-to-Air Heat Exchanger by Finite Volume Method
by Qinggong Liu, Zhenyu Du and Yi Fan
Energies 2018, 11(6), 1542; https://doi.org/10.3390/en11061542 - 13 Jun 2018
Cited by 15 | Viewed by 3714
Abstract
A comprehensive numerical study on coupled heat and mass transfer in an earth-to-air heat exchanger (EAHE) is conducted by self-complied program based on the finite volume method. The soil thermal and moisture coupled characteristics in the vicinity of the pipe and the thermal [...] Read more.
A comprehensive numerical study on coupled heat and mass transfer in an earth-to-air heat exchanger (EAHE) is conducted by self-complied program based on the finite volume method. The soil thermal and moisture coupled characteristics in the vicinity of the pipe and the thermal performance of the EAHE are evaluated by a two-dimensional simulation model. The model of the EAHE is verified by the experimental data, which achieved a good agreement with each other. The numerical results show that there is an obvious moisture peak in the radial direction, and the peak position radially moves away from the wall of the pipe over time. It is also found that the thermal performance of the heat and mass transfer model in soil is better than the pure heat conduction model. Full article
(This article belongs to the Special Issue Building renewable energy and thermal energy storage system 2018)
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19 pages, 5386 KiB  
Article
Study of Power Quality at the Point of Common Coupling of a Low Voltage Grid and a Distributed Generation System of 7.8 kWp in a Tropical Region
by Agustín Valverde Granja, Teófilo Miguel De Souza, Pedro Magalhães Sobrinho and Daniel Felipe Arévalo Santos
Energies 2018, 11(6), 1539; https://doi.org/10.3390/en11061539 - 13 Jun 2018
Cited by 9 | Viewed by 3102
Abstract
In this paper we analyze an experimental 1000 kWh/month distributed generation system in a tropical region connected to a point of common coupling in a low voltage grid that was characterized according to NTC 5001. This photovoltaic system has 7.8 kWp and uses [...] Read more.
In this paper we analyze an experimental 1000 kWh/month distributed generation system in a tropical region connected to a point of common coupling in a low voltage grid that was characterized according to NTC 5001. This photovoltaic system has 7.8 kWp and uses 30 polycrystalline silicon-panels of 260 Wp each. Its maximum energy produced was 850 kWh/month, equivalent to 72.65% of the installed capacity. Finally, there was an increase of 2% with respect to the minimum voltage value that was recorded. The voltage unbalance decreases between 3.5 and 70% and voltage harmonics in each line increased by 7% on line U1, 0.8% on U2, 3% on U3 and current harmonics have a 22% increase. Likewise, the total active and reactive power were increased by 58% and 42% respectively, and the thermography study allowed to establish a temperature increase at the point of common coupling of 7.5%. Therefore, it is expected that this paper can serve as a reference for the application of Colombian law 1715 in solar energy. Full article
(This article belongs to the Special Issue Building renewable energy and thermal energy storage system 2018)
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18 pages, 3063 KiB  
Article
Feasibility Study of Self-Sufficient Solar Cooling Façade Applications in Different Warm Regions
by Alejandro Prieto, Ulrich Knaack, Thomas Auer and Tillmann Klein
Energies 2018, 11(6), 1475; https://doi.org/10.3390/en11061475 - 6 Jun 2018
Cited by 7 | Viewed by 3431
Abstract
Small-scale systems and integrated concepts are currently being explored to promote the widespread application of solar cooling technologies in buildings. This article seeks to expand application possibilities by exploring the feasibility of solar cooling integrated façades, as decentralized self-sufficient cooling modules on different [...] Read more.
Small-scale systems and integrated concepts are currently being explored to promote the widespread application of solar cooling technologies in buildings. This article seeks to expand application possibilities by exploring the feasibility of solar cooling integrated façades, as decentralized self-sufficient cooling modules on different warm regions. The climate feasibility of solar electric and solar thermal concepts is evaluated based on solar availability and local cooling demands to be met by current technical possibilities. Numerical calculations are employed for the evaluation, considering statistical climate data; cooling demands per orientation from several simulated scenarios; and state-of-the-art efficiency values of solar cooling technologies, from the specialized literature. The main results show that, in general, warm-dry climates and east/west orientations are better suited for solar cooling façade applications, compared to humid regions and north/south orientations. Results from the base scenario show promising potential for solar thermal technologies, reaching a theoretical solar fraction of 100% in several cases. Application possibilities expand when higher solar array area and lower tilt angle on panels are considered, but these imply aesthetical and constructional constraints for façade design. Finally, recommendations are drafted considering prospects for the exploration of suitable technologies for each location, and façade design considerations for the optimization of the solar input per orientation. Full article
(This article belongs to the Special Issue Building renewable energy and thermal energy storage system 2018)
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21 pages, 35495 KiB  
Article
In Situ Experiment and Numerical Model Validation of a Borehole Heat Exchanger in Shallow Hard Crystalline Rock
by Mateusz Janiszewski, Enrique Caballero Hernández, Topias Siren, Lauri Uotinen, Ilmo Kukkonen and Mikael Rinne
Energies 2018, 11(4), 963; https://doi.org/10.3390/en11040963 - 17 Apr 2018
Cited by 9 | Viewed by 5751
Abstract
Accurate and fast numerical modelling of the borehole heat exchanger (BHE) is required for simulation of long-term thermal energy storage in rocks using boreholes. The goal of this study was to conduct an in situ experiment to validate the proposed numerical modelling approach. [...] Read more.
Accurate and fast numerical modelling of the borehole heat exchanger (BHE) is required for simulation of long-term thermal energy storage in rocks using boreholes. The goal of this study was to conduct an in situ experiment to validate the proposed numerical modelling approach. In the experiment, hot water was circulated for 21 days through a single U-tube BHE installed in an underground research tunnel located at a shallow depth in crystalline rock. The results of the simulations using the proposed model were validated against the measurements. The numerical model simulated the BHE’s behaviour accurately and compared well with two other modelling approaches from the literature. The model is capable of replicating the complex geometrical arrangement of the BHE and is considered to be more appropriate for simulations of BHE systems with complex geometries. The results of the sensitivity analysis of the proposed model have shown that low thermal conductivity, high density, and high heat capacity of rock are essential for maximising the storage efficiency of a borehole thermal energy storage system. Other characteristics of BHEs, such as a high thermal conductivity of the grout, a large radius of the pipe, and a large distance between the pipes, are also preferred for maximising efficiency. Full article
(This article belongs to the Special Issue Building renewable energy and thermal energy storage system 2018)
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12 pages, 2315 KiB  
Article
Flat Concentrator Photovoltaic System with Lateral Displacement Tracking for Residential Rooftops
by Ngoc Hai Vu and Seoyong Shin
Energies 2018, 11(1), 114; https://doi.org/10.3390/en11010114 - 3 Jan 2018
Cited by 6 | Viewed by 5628
Abstract
We present a design for a flat concentrating photovoltaic (CPV) system that requires only lateral displacement for sun-tracking, intended for residential rooftop applications. Compared with flat-plate photovoltaics (PVs), CPV technology is essential for reducing the use of semi-conductor materials, which also enables cheaper [...] Read more.
We present a design for a flat concentrating photovoltaic (CPV) system that requires only lateral displacement for sun-tracking, intended for residential rooftop applications. Compared with flat-plate photovoltaics (PVs), CPV technology is essential for reducing the use of semi-conductor materials, which also enables cheaper solar power generation. Existing CPV designs are more bulky and complex than traditional PV panel techniques and are therefore better suited to solar farms than rooftop use. In this study, we explore an alternate approach, employing a mirror-coated lenslet array, to demonstrate a flat CPV system for rooftop installation. This mirror-coated lenslet array collects solar radiation and concentrates it with a very short focal length. The lateral movement of lenslet focal points according to a changing incident angle of sunlight allows for the use of a lateral displacement tracking mechanism. A square array of solar cells integrated on a transparent sheet is placed on top of a mirror-coated lenslet array to collect focused sunlight and convert it to electricity. The proposed CPV panel can be achieved with a 35 mm thickness. Simulation models were developed using commercial optical design software (LightTools). The simulation demonstrates an optical efficiency of up to 89.5% when the concentration ratio of the system is fixed to 50×. The simplicity of the structure enables cheaper mass production. Our quest for a lateral displacement sun-tracking mechanism also shows that the system has a high tolerance, thereby enabling cost savings by replacing a highly precise, active sun-tracking system with a lower-accuracy system. The presented flat CPV is a strong candidate for a low-cost, high-efficiency solar energy system that can be installed on the rooftops of residential buildings to deliver energy savings. Full article
(This article belongs to the Special Issue Building renewable energy and thermal energy storage system 2018)
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