F. Reis, M. C. Brito, V. Corregidor, J. Wemans, and G. Sorasio, "Modeling the performance of low concentration photovoltaic systems," Solar Energy Materials and Solar Cells, vol. 94, no. 7, pp. 1222–1226, Jul. 2010. doi: 10.1016/j.solmat.2010.03.010[edit | edit source]
A theoretical model has been developed to describe the response of V-trough systems in terms of module temperature, power output and energy yield using as inputs the atmospheric conditions. The model was adjusted to DoubleSun® concentration technology, which integrates dual-axis tracker and conventional mono-crystalline Si modules. The good agreement between model predictions and the results obtained at WS Energia laboratory, Portugal, validated the model. It is shown that DoubleSun® technology increases up to 86% the yearly energy yield of conventional modules relative to a fixed flat-plate system. The model was also used to perform a sensitivity analysis, in order to highlight the relevance of the leading working parameters (such as irradiance) in system performance (energy yield and module temperature). Model results show that the operation module temperature is always below the maximum working temperature defined by the module manufacturers.
G. M. Tina and P. F. Scandura, "Case study of a grid connected with a battery photovoltaic system: V-trough concentration vs. single-axis tracking," Energy Conversion and Management, vol. 64, pp. 569–578, Dec. 2012. doi: 10.1016/j.enconman.2012.05.029[edit | edit source]
Photovoltaic systems (PVSs) combined with either some form of storage, such as a battery energy storage system (BESS), or direct load control, can play a crucial role in achieving a more economical operation of the electric utility system while enhancing its reliability with additional energy sources. At the same time, it is also important to use cost-effective PV solutions. In this context, a low-concentration PVS (CPVS) is analysed as a feasible alternative. This paper, present a case study of a complex PVS, composed of two PVSs, a storage system (BEES) and an inverter that allows the system to operate in both the island and grid-connected modes. The first PVS, is a 2.76-kWp single-axis tracking system (azimuth) with modules facing south and tilted 30°, while the second PVS is a dual-axis tracking system, rated 860 Wp, consisting of a concentrator at the flat mirrors. The system is installed on the roof of the main building of the "ITIS Marconi" school (Italy). A detailed description of the system is provided, and preliminary operating data are presented and discussed. The efficiencies of the PV systems are calculated and measured to evaluate the cost effectiveness of a low-concentration system.
Compound Parabolic Concentrators (CPC)[edit | edit source]
The Compound Parabolic Concentrator (CPC) is a nonimaging optical-design concept that allows maximum concentration of incident energy onto a receiver. This design incorporates a trough-like reflecting wall by which radiation is concentrated to the maximum allowed by physical principles of optics.
A. Rabl, N. B. Goodman, and R. Winston, "Practical design considerations for CPC solar collectors," Solar Energy, vol. 22, no. 4, pp. 373–381, Jan. 1979. doi: 10.1016/0038-092X(79)90192-0[edit | edit source]
Several practical problems are addressed which arise in the design of solar collectors with compound parabolic concentrators (CPC's). They deal with the selection of a receiver type, the optimum method for introducing a gap between receiver and reflector to minimize optical and thermal losses, and the effect of a glass envelope around the receiver. This paper also deals with the effect of mirror errors and receiver misalignment, and the effect of the temperature difference between fluid and absorber plate. The merits of a CPC as a second stage concentrator are analyzed.
T. Tao, Z. Hongfei, H. Kaiyan, and A. Mayere, "A new trough solar concentrator and its performance analysis," Solar Energy, vol. 85, no. 1, pp. 198–207, 2011. doi: 10.1016/j.solener.2010.08.017[edit | edit source]
- A solar concentrator system consisting of a CPC, a secondary reflection plane mirror, and a parabolic trough concentrator.
The operation principle and design method of a new trough solar concentrator is presented in this paper. Some important design parameters about the concentrator are analyzed and optimized. Their magnitude ranges are given. Some characteristic parameters about the concentrator are compared with that of the conventional parabolic trough solar concentrator. The factors having influence on the performance of the unit are discussed. It is indicated through the analysis that the new trough solar concentrator can actualize reflection focusing for the sun light using multiple curved surface compound method. It also has the advantages of improving the work performance and environment of high-temperature solar absorber and enhancing the configuration intensity of the reflection surface.
N. Sarmah, B. S. Richards, and T. K. Mallick, "Evaluation and optimization of the optical performance of low-concentrating dielectric compound parabolic concentrator using ray-tracing methods," Applied Optics, vol. 50, no. 19, p. 3303, Jul. 2011.doi: 10.1364/AO.50.003303[edit | edit source]
Presented a detailed design concept and optical performance evaluation of stationary dielectric asym-metric compound parabolic concentrators (DiACPCs) using ray-tracing methods. Three DiACPC designs,DiACPC-55, DiACPC-66, and DiACPC-77, of acceptance half-angles (0° and 55°), (0° and 66°), and (0° and77°), respectively, are designed in order to optimize the concentrator for building façade photovoltaicapplications in northern latitudes (>55°N). The dielectric concentrator profiles have been realizedvia truncation of the complete compound parabolic concentrator profiles to achieve a geometric concen-tration ratio of 2.82. Ray-tracing simulation results show that all rays entering the designed concentra-tors within the acceptance half-angle range can be collected without escaping from the parabolic sidesand aperture. The maximum optical efficiency of the designed concentrators is found to be 83%, whichtends to decrease with the increase in incidence angle. The intensity is found to be distributed at thereceiver (solar cell) area in an inhomogeneous pattern for a wide range of incident angles of direct solarirradiance with high-intensity peaks at certain points of the receiver. However, peaks become moreintense for the irradiation incident close to the extreme acceptance angles, shifting the peaks to the edgeof the receiver. Energy flux distribution at the receiver for diffuse radiation is found to be homogeneouswithin �12% with an average intensity of 520 W/m2.
M. A. Schuetz, K. A. Shell, S. A. Brown, G. S. Reinbolt, R. H. French, and R. J. Davis, "Design and Construction of a ~7x Low-Concentration Photovoltaic System Based on Compound Parabolic Concentrators," IEEE Journal of Photovoltaics, vol. 2, no. 3, pp. 382–386, Jul. 2012. doi: 10.1109/JPHOTOV.2012.2186283[edit | edit source]
Reports on the design, construction, and initial performance measurements of a low-concentration photovoltaic system based on compound parabolic concentrators (CPCs). The system is approximately a 7× concentration system and uses commercially available laser groove buried contact monocrystalline silicon photovoltaic cells. The CPCs are fabricated using a second-surface aluminized acrylic mirror with proven weather durability. The asymmetric CPC optical design was driven by a balance between concentration factor, thermal issues, and optical angle of acceptance and was thoroughly evaluated by optical ray tracing. The design was targeted for a single-axis tracking system, with extruded aluminum heat sinks doubling as structural components. We fabricated a 120-cell (10 × 12) prototype array, and over three months of operation, we estimated an approximate peak total system power efficiency of 7.9%, limited mostly by the CPC optical efficiency (∼55%) and the cell conversion efficiency. We discuss several issues regarding system performance, reliability, and cost.
N. Sellami and T. K. Mallick, "Optical efficiency study of PV Crossed Compound Parabolic Concentrator," Applied Energy, vol. 102, pp. 868–876, Feb. 2013. doi: 10.1016/j.apenergy.2012.08.052[edit | edit source]
- Uses a ray-tracing method to design and optimize three stationary dielectric asymmetric compound parabolic concentrators (DiACPCs) with acceptance half-angles of (0°/55°), (0°/66°) and (0°/77°), respectively to optimize in order to optimize the designs of concentrator applications in northern latitudes (>55 °N)
- Concludes that Energy flux distribution at the receiver for diffuse radiation is found to be homogeneous
H. Ali and P. Gandhidasan, "Performance Evaluation of Photovoltaic String with Compound Parabolic Concentrator," Journal of Clean Energy Technologies, vol. 3, no. 3, pp. 170–175, 2015. doi: 10.7763/JOCET.2015.V3.190[www.jocet.org/papers/190-R032.pdf][edit | edit source]
Photovoltaic (PV) system is used to directly converting the solar energy into the electrical energy. Compound Parabolic Concentrator (CPC) is a non-imaging concentrator which is considered in this study for reducing the cost of electrical energy. Two configurations are numerically studied namely one with simple typical flat PV string and the other PV string with CPC. The truncated CPC with concentration ratio of 2.3 and an acceptance angle of 41.75° is considered in the analysis of PV string with CPC (PV-CPC). Transient System Simulation Software (TRNSYS) is used for the evaluation of PV cell performance with and without CPC. The mathematical model for PV and PV-CPC is developed for the performance estimation of thermal and electrical characteristic of the system. Engineering Equation Solver (EES) code is written to solve the mathematical model and is linked with TRNSYS for simulation. The simulation is carried out for the average day of the months of June and December for Riyadh city. Results indicated that the use of the CPC increases the absorbed energy and electrical power output of PV system. The electrical power of PV string increases almost 35% when CPC is used with PV compared to simple typical flat PV string.
Booster reflectors[edit | edit source]
H. Tabor, "Mirror boosters for solar collectors," Solar Energy, vol. 10, no. 3, pp. 111–118, Jul. 1966. doi: 10.1016/0038-092X(66)90025-9[edit | edit source]
Fixed flat-plate collectors produce outputs on clear days that are low and peaky: the addition of side mirrors to increase the amount of radiation reaching the collector increases the yield and permits higher temperatures of operation. By considering direct and diffuse components of sunlight separately and the geometry of the system, the instantaneous increase due to the mirrors can be determined and integrated graphically over the whole day. As indicated in an earlier paper, the retention efficiency N is a more basic characteristic of collectors than the collection efficiency η even though they are related by η = (αβ) N. Because (αβ) varies during the day the concept of "filtered" sunshine is introduced. This permits treating the collector or, if (αβ) were constant but using a modified or filtered sunshine input curve, large changes in (αβ) can be accommodated without having to use a different filter characteristic. The Shuman case of side mirrors on the north and south edges of a collector is discussed in detail: the yield is increased but is very peaky. An alternative system uses an east-facing mirror placed on the west edge of the collector in the forenoon, which is transferred (manually) at noon to be west facing on the east edge. This system produces about the same amount of boost as the Shuman case but the output is approximately rectangular. Several configurations and transposition systems are given: one has been used in a turbine power installation.
M. Rönnelid, B. Karlsson, P. Krohn, and J. Wennerberg, "Booster reflectors for PV modules in Sweden," Prog. Photovolt: Res. Appl., vol. 8, no. 3, pp. 279–291, May 2000. doi: 10.1002/1099-159X(200005/06)8:3<279::AID-PIP316>3.0.CO;2-#[edit | edit source]
The performance of photovoltaic modules with planar booster reflectors with variable length and tilts for Swedish conditions is analysed. It is shown that a stationary flat booster reflector can increase the annual output of the module in the order of 20–25%, provided that the influence of short lateral length of the reflector and temperature rise can be limited. The principal difference between using modules with crystalline silicon cells or thin film modules is discussed and numerical examples together with experimental results are given. The electrical coupling of rows in a PV module and/or the electrical coupling of modules in a PV installation are important when booster reflectors are used. If horizontal rows of cells in a module are parallel coupled, the module better utilises radiation reflected from a booster reflector in front than if the rows are coupled in series. Low serial resistance, low module temperature and small edge effects, i.e. not too short lateral length of the booster reflector, are important to achieve good performance of modules with booster reflectors.
H. Tanaka, "Solar thermal collector augmented by flat plate booster reflector: Optimum inclination of collector and reflector," Applied Energy, vol. 88, no. 4, pp. 1395–1404, Apr. 2011. doi: 10.1016/j.apenergy.2010.10.032[edit | edit source]
Reports a theoretical analysis of a solar thermal collector with a flat plate top reflector. The top reflector extends from the upper edge of the collector, and can be inclined forwards or backwards from vertical according to the seasons. Its theoretically predicted the daily solar radiation absorbed on an absorbing plate of the collector throughout the year, which varies considerably with the inclination of both the collector and reflector, and is slightly affected by the ratio of the reflector and collector length. It is found the optimum inclination of the collector and reflector for each month at 30°N latitude. An increase in the daily solar radiation absorbed on the absorbing plate over a conventional solar thermal collector would average about 19%, 26% and 33% throughout the year by using the flat plate reflector when the ratio of reflector and collector length is 0.5, 1.0 and 2.0 and both the collector and reflector are adjusted to the proper inclination.
Advantage of corrugated reflectors[edit | edit source]
M. RÖNNELID and B. KARLSSON, "THE USE OF CORRUGATED BOOSTER REFLECTORS FOR SOLAR COLLECTOR FIELDS," Solar Energy, vol. 65, no. 6, pp. 343–351, Apr. 1999. doi:10.1016/S0038-092X(99)00009-2[edit | edit source]
The use of booster reflectors in front of solar collectors is an established technique for increasing the irradiation onto solar collectors. By using corrugated instead of flat booster reflectors it is possible to increase the annual irradiation onto the collector plane, thereby maximising the annual output from the collector–reflector arrangement. The paper includes a description of a ray tracing program which calculates the annual optical performance of a collector–booster reflector system with different V-corrugated reflectors. Calculations based on Swedish solar radiation data show that the use of a booster reflector with varying V-corrugations along the reflector, instead of a flat booster reflector, can increase the annual reflected direct radiation on to the collector by 10%. This is estimated to result in a 3% increase in the annual collector output. The ray-tracing calculations are compared with measurements of the reflection characteristics of single V-shaped reflector arrangements.
B. Perers, B. Karlsson, and M. Bergkvist, "Intensity distribution in the collector plane from structured booster reflectors with rolling grooves and corrugations," Solar Energy, vol. 53, no. 2, pp. 215–226, Aug. 1994.doi: 10.1016/0038-092X(94)90485-5[edit | edit source]
While testing different reflector materials for external reflectors for solar collector arrays, it was found that standard rolled aluminium and corrugated aluminium materials could perform almost as well as mirror-like materials. A ray tracing model was developed to calculate the intensity in the collector plane for solar radiation from reflector materials with grooves or corrugations. Laboratory measurements, for reflector samples, with a specially designed spectral scatterometer were used to determine the angular intensity distribution of the reflected radiation. Calculations with the model using measured intensity distributions show that the scatter from aluminium materials with rolling grooves will be directed close to the specular direction and along an almost circular arc in the collector plane. The intensity in the collector plane will be redistributed slightly upward or downward depending on the season and time of day; therefore, both an increase and decrease in average intensity can occur during the year relative to a mirror-like material with the same total reflectance. For rolled aluminium, a small performance improvement can be achieved compared to a mirror reflector with equal total reflectance. Corrugated surfaces will yield a significant increase in average intensity onto the collector aperture at times when the radiation from a mirror-like reflector would otherwise be lost above the collector.
Tracking Systems[edit | edit source]
Solar tracking systems are actuator devices employed to concentrate reflectors towards the Sun's direction. Concentrators should be able to direct the sunlight precisely onto solar cells with the aid of these devices. Single axis systems can turn the panels around the centre axis while Dual axis tracking is used to position a mirror and concentrate incoming radiation along a fixed axis towards a stationary receiver.
A. K. Agarwal, "Two axis tracking system for solar concentrators," Renewable Energy, vol. 2, no. 2, pp. 181–182, Apr. 1992. doi: 10.1016/0960-1481(92)90104-B[edit | edit source]
A two axis tracking system is described for the focussing of sunlight in paraboloid-type solar reflectors used in solar thermal devices like solar cookers. This system consists of wormgear drives and four bar type kinematic linkages for effortless and accurate focussing of reflectors at low cost.
J. C. Arboiro and G. Sala, "'Self-learning Tracking': a New Control Strategy for PV Concentrators," Prog. Photovolt: Res. Appl., vol. 5, no. 3, pp. 213–226, May 1997. doi: 10.1002/(SICI)1099-159X(199705/06)5:3<213::AID-PIP171>3.0.CO;2-7[edit | edit source]
Usually the tracking system is not given much importance when designing a photovoltaic (PV) concentrator, partly because the intensive work carried out on this subject has provided it with a false sense of maturity. However, only a few tracking systems have ever been successfully implemented in practical concentrators and many systems never worked in spite of the perfect theoretical design. In this paper we present a review of the experience in tracking systems from the Institute of Solar Energy. This experience runs in parallel with the evolution and development of such systems. It starts with the SANDIA experience in 1977 and moves on to discussing the problems and lessons learned with both open and closed loop systems in the Ramón Areces project (1978). After a brief description of self-aligning systems, we finish by discussing a new approach to tracking: the self-learning concept. In this case the tracking system monitors continuously the operation current, refines constantly its knowledge of the errors and misalignments affecting tracking accuracy and performs the corrections required. The algorithm for this scheme, which has already proved reliable for operation in the EUCLIDES concentrator prototype (1995 to date), is described in some depth.
V. Poulek and M. Libra, "New solar tracker," Solar Energy Materials and Solar Cells, vol. 51, no. 2, pp. 113–120, Feb. 1998.doi : 10.1016/S0927-0248(97)00276-6[edit | edit source]
A new very simple solar tracker is described in detail in the paper as well as a tracking strategy which enables high-collectible energy surplus at medium tracking accuracy
B. J. Huang and F. S. Sun, "Feasibility study of one axis three positions tracking solar PV with low concentration ratio reflector," Energy Conversion and Management, vol. 48, no. 4, pp. 1273–1280, Apr. 2007. doi: 10.1016/j.enconman.2006.09.020[edit | edit source]
A new PV design, called "one axis three position sun tracking PV module", with low concentration ratio reflector was proposed in the present study. Every PV module is designed with a low concentration ratio reflector and is mounted on an individual sun tracking frame. The one axis tracking mechanism adjusts the PV position only at three fixed angles (three position tracking): morning, noon and afternoon. This "one axis three position sun tracking PV module" can be designed in a simple structure with low cost. A design analysis was performed in the present study. The analytical results show that the optimal stopping angle β in the morning or afternoon is about 50° from the solar noon position and the optimal switching angle that controls the best time for changing the attitude of the PV module is half of the stopping angle, i.e. θH = β/2, and both are independent of the latitude. The power generation increases by approximately 24.5% as compared to a fixed PV module for latitude ϕ < 50°. The analysis also shows that the effect of installation misalignment away from the true south direction is negligible (<2%) if the alignment error is less than 15°. An experiment performed in the present study indicates that the PV power generation can increase by about 23% using low concentration (2X) reflectors. Hence, combining with the power output increase of 24.5%, by using one axis three position tracking, the total increase in power generation is about 56%. The economic analysis shows that the price reduction is between 20% and 30% for the various market prices of flat plate PV modules.
H. Mousazadeh, A. Keyhani, A. Javadi, H. Mobli, K. Abrinia, and A. Sharifi, "A review of principle and sun-tracking methods for maximizing solar systems output," Renewable and Sustainable Energy Reviews, vol. 13, no. 8, pp. 1800–1818, Oct. 2009. doi: 10.1016/j.rser.2009.01.022[edit | edit source]
Finding energy sources to satisfy the world's growing demand is one of society's foremost challenges for the next half-century. The challenge in converting sunlight to electricity via photovoltaic solar cells is dramatically reducing $/watt of delivered solar electricity. In this context the sun trackers are such devices for efficiency improvement.The diurnal and seasonal movement of earth affects the radiation intensity on the solar systems. Sun-trackers move the solar systems to compensate for these motions, keeping the best orientation relative to the sun. Although using sun-tracker is not essential, its use can boost the collected energy 10–100% indifferent periods of time and geographical conditions. However, it is not recommended to use tracking system for small solar panels because of high energy losses in the driving systems. It is found that thepower consumption by tracking device is 2–3% of the increased energy.In this paper different types of sun-tracking systems are reviewed and their cons and pros arediscussed. The most efficient and popular sun-tracking device was found to be in the form of polar-axis and azimuth/elevation types.
C.-Y. Lee, P.-C. Chou, C.-M. Chiang, and C.-F. Lin, "Sun Tracking Systems: A Review," Sensors, vol. 9, no. 5, pp. 3875–3890, May 2009. doi: 10.3390/s90503875[edit | edit source]
The output power produced by high-concentration solar thermal and photovoltaic systems is directly related to the amount of solar energy acquired by the system, and it is therefore necessary to track the sun's position with a high degree of accuracy. Many systems have been proposed to facilitate this task over the past 20 years. Accordingly, this paper commences by providing a high level overview of the sun tracking system field and then describes some of the more significant proposals for closed-loop and open-loop types of sun tracking systems.
S. Ozcelik, H. Prakash, and R. Challoo, "Two-Axis Solar Tracker Analysis and Control for Maximum Power Generation," Procedia Computer Science, vol. 6, pp. 457–462, 2011. doi: 10.1016/j.procs.2011.08.085[edit | edit source]
Many of the solar panels throughout the world are positioned with the fixed angles. To maximize the use of the solar panel we use a solar tracker which orients itself along the direction of the sunlight. The solar tracker positions the panel in a hemispheroidal rotation to track the movement of the sun and thus increase the total electricity generation. This paper focuses on the development of new approach to control the movement of the solar panel. The purpose of this paper is to simulate and implement the most suitable and efficient control algorithm on the dual-axis solar tracker which can rotate in azimuth and elevation direction. The simulation gives the tracker angles that position the solar panel along the sun's rays such that maximum solar irradiation is absorbed by the panel.
S. I. Klychev, A. K. Fazylov, S. A. Orlov, and A. V. Burbo, "Design factors of sensors for the optical tracking systems of solar concentrators," Appl. Sol. Energy, vol. 47, no. 4, pp. 321–322, Mar. 2012. doi: 10.3103/S0003701X11040086[edit | edit source]
Basic diagrams for the sensors of the optical tracking systems of solar concentrators are considered, the design factors that determine their accuracy are analyzed, a new sensor design is suggested, and its optimal parameters are determined.
P. K. Sen, K. Ashutosh, K. Bhuwanesh, Z. Engineer, S. Hegde, P. V. Sen, and P. Davies, "Linear Fresnel Mirror Solar Concentrator with Tracking," Procedia Engineering, vol. 56, pp. 613–618, 2013. doi: 10.1016/j.proeng.2013.03.167[edit | edit source]
Solar energy is the most abundant, widely distributed and clean renewable energy resource. Since the insolation intensity is only in the range of 0.5 - 1.0 kW/m2, solar concentrators are required for attaining temperatures appropriate for medium and high temperature applications. The concentrated energy is transferred through an absorber to a thermal fluid such as air, water or other fluids for various uses. This paper describes design and development of a 'Linear Fresnel Mirror Solar Concentrator' (LFMSC) using long thin strips of mirrors to focus sunlight onto a fixed receiver located at a common focal line. Our LFMSC system comprises a reflector (concentrator), receiver (target) and an innovative solar tracking mechanism. Reflectors are mirror strips, mounted on tubes which are fixed to a base frame. The tubes can be rotated to align the strips to focus solar radiation on the receiver (target). The latter comprises a coated tube carrying water and covered by a glass plate. This is mounted at an elevation of few meters above the horizontal, parallel to the plane of the mirrors. The reflector is oriented along north-south axis. The most difficult task is tracking. This is achieved by single axis tracking using a four bar link mechanism. Thus tracking has been made simple and easy to operate. The LFMSC setup is used for generating steam for a variety of applications.
S. Yilmaz, H. Riza Ozcalik, O. Dogmus, F. Dincer, O. Akgol, and M. Karaaslan, "Design of two axes sun tracking controller with analytically solar radiation calculations," Renewable and Sustainable Energy Reviews, vol. 43, pp. 997–1005, Mar. 2015. doi: 10.1016/j.rser.2014.11.090[edit | edit source]
In order to design new PV systems that will be installed to operate in more efficient and more feasible way, it is necessary to analyze parameters like solar radiation values, the angle of incidence of the genus, temperature etc. Therefore, in this study, theoretical works have been performed for solar radiation and angle of incidence values of any location, plus an experimental study was carried out on a system tracking the sun in two axes and in a fixed system. The performed prototype is also adapted into a PV system with 4.6 kW power. Theoretical data are consistent with the data obtained from the PV system with 4.6 kW power. This study will be an important guide for the future PV power stations.
Large Scale PV systems[edit | edit source]
C. Deline, A. Dobos, S. Janzou, J. Meydbray, and M. Donovan, "A simplified model of uniform shading in large photovoltaic arrays," Solar Energy, vol. 96, pp. 274–282, Oct. 2013. doi:10.1016/j.solener.2013.07.008[edit | edit source]
Kirigami approach[edit | edit source]
Kirigami and Technology[edit | edit source]
Graham P. Collins, "Kirigami and technology cut a fine figure, together," Proceedings of the National Academy of Sciences, vol. 113, no. 2, pp. 240–241. doi:10.1073/pnas.1523311113[edit | edit source]
- Notion : Kirigami is a variant of origami, the art of paper folding. The words derive from the Japanese for cutting (kiru), folding (oru), and paper (kami).
- Aim: To discuss how this art form has emerged into science to help develop new technologies.Author aims to provide insights into collaborations leading to authentic design forms in different fields.
- Summary: 1. Kirigami pathway provides an excellent design opportunity to convert 2D forms to 3D forms just by simple folding and cutting transforms which can be applied from various scales nano to meso. 2. Kirigami way can alleviate stresses in structures leading to fracture and thus can be widely applied in 3D structures of optoelectronics and nanostructured biomedical devices. 3. This design pathway inspired people from ASU to manufacture flexible chain of Li-Ion batteries and also provided flexible design methodologies of single atom thick, out structured graphene sheets. This paper surmises current and future creative collaborations with a broader view of invocating new design principles.
T. C. Shyu, P. F. Damasceno, P. M. Dodd, A. Lamoureux, L. Xu, M. Shlian, M. Shtein, S. C. Glotzer, and N. A. Kotov, "A kirigami approach to engineering elasticity in nanocomposites through patterned defects," Nat Mater, vol. 14, no. 8, pp. 785–789, Aug. 2015. doi: 10.1038/nmat4327[edit | edit source]
Efforts to impart elasticity and multifunctionality in nanocomposites focus mainly on integrating polymeric and nanoscale components. Yet owing to the stochastic emergence and distribution of strain-concentrating defects and to the stiffening of nanoscale components at high strains, such composites often possess unpredictable strain–property relationships. Here, by taking inspiration from kirigami—the Japanese art of paper cutting— a network of notches were made in rigid nanocomposite and other composite sheets by top-down patterning techniques prevents unpredictable local failure and increases the ultimate strain of the sheets from 4 to 370%. The sheets' tensile behaviour can be accurately predicted through finite-element modelling. Moreover, in marked contrast to other stretchable conductors the electrical conductance of the stretchable kirigami sheets is maintained over the entire strain regime. The unique properties of kirigami nanocomposites as plasma electrodes open up a wide range of novel technological solutions for stretchable electronics and optoelectronic devices, among other application possibilities.
How does a Kirigami approach helps solar Photovoltaics?[edit | edit source]
A. Lamoureux, K. Lee, M. Shlian, S. R. Forrest, and M. Shtein, "Dynamic kirigami structures for integrated solar tracking," Nat Commun, vol. 6, p. 8092, Sep. 2015. doi:10.1038/ncomms9092[edit | edit source]
Optical tracking is often combined with conventional flat panel solar cells to maximize electrical power generation over the course of a day. However, conventional trackers are complex and often require costly and cumbersome structural components to support system weight. kirigami designing is used to as integral to the structure at the substrate level for GaAs. Specifically, an elegant cut pattern is made, which are then stretched to produce an array of tilted surface elements which can be controlled to within ±1°.Source angle and extent of tracking are varied and tested. The combined optical and mechanical properties of the tracking system demonstrates a mechanically robust system with optical tracking efficiencies matching conventional trackers. This design suggests a pathway towards enabling new applications for solar tracking, as well as inspiring a broader range of optoelectronic and mechanical devices.
Modelling[edit | edit source]
Link directly to Low level concentration for PV applications literature review
BDRV Based Modelling[edit | edit source]
R. W. Andrews, A. Pollard, and J. M. Pearce, "Photovoltaic system performance enhancement with non-tracking planar concentrators: Experimental results and BDRF based modelling," in Photovoltaic Specialists Conference (PVSC), 2013 IEEE 39th, 2013, pp. 0229–0234. doi: 10.1109/PVSC.2013.6744136[edit | edit source]
Non-tracking planar concentrators are a low-cost method of increasing the performance of traditional solar photovoltaic (PV) systems. In this study such an outdoor system has been shown to improve energy yield by 45% for a traditional flat glass module and by 35% for a prismatic glass crystalline silicon module. In addition, this paper presents new methodologies for properly modelling this type of system design and experimental results using a bi-directional reflectance function (BDRF) of non-ideal surfaces rather than traditional geometric optics. This methodology allows for the evaluation and eventual optimization of specular and non-specular reflectors in planar concentration systems.
Citations[edit | edit source]
