Design & Models[edit | edit source]
Abstract: The purpose of this paper is to provide a technical and economic evaluation of the value of the RepRap as an entry-level 3-D printer in the developing world and provide a cost effective solar photovoltaic (PV) racking solution to better serve the developing world and aid in the acceleration of their economic and socioeconomic growth. A customizable open-source PV racking concept is designed, prototyped for three types of modules, constructed into systems, and outdoor tested under extreme conditions for one year. An economic analysis is provided along with a technical evaluation of the system, which found the proposed racking system can be successfully printedwith RepRap 3-D printers and saves between 85% and 92% fromcommercially available alternatives depending on the plastic used for printing. In addition, the plastic parts proved able to withstand some of the harshest outdoor conditions and due to the free and open-source nature of the designs, it allows the system to be adapted to custom applications in any region in the world more easily than any commercial alternatives. The results indicate that the 3-D printable X-wire solar photovoltiac racking system has the potential to aid in the acceleration of solar deployment in the developing world by providing a low cost PV racking solution.
- "X-Wire" PLA (83% savings) & HDPE (92% savings) backets + wiring (10, 20 deg)
- Recyclebot + waste plastic option
- Winter cond. Tested; economically compared to UNIRAC RM
- Strength of Al vs. PLA
- 3D printed V = 80% reduction of racking cost
Total U.S. Cost Evaluation of Low-Weight Tension-Based Photovoltaic Flat-Roof Mounted Racking[edit | edit source]
Abstract: The economics in the U.S. of solar photovoltaic (PV) systems is changing rapidly as the cost per unit power of PV modules has dropped quickly. These costs reductions have two important results: marked decrease in levelized cost of electricity (LCOE) into ranges competitive or better than traditional electricity-generation technologies and the economic role of racking has been gaining prominence relative to that of modules. As the relative importance of costs of PV racking has been marginal historically, there has been relatively little progress on reducing the materials and costs associated with it, which has caused racking to contribute to a significant portion of costs of entire PV systems. In order to overcome this challenge this study investigates a novel low-weight PV racking system for commercial rooftops based on crossed cables (X-wires) and compares it to racking systems already available on the market on capital costs, labor costs for installation, and technical specifications such as adaptability and power packing factor. The results of over 80% cost reduction and 33% increase in power density are presented and conclusions are drawn about the potential for tension-based racking systems to further reduce total PV systems costs on commercial flat roof tops resulting in LCOE savings of $0.01-$0.02/kWh.
- Focus on module cost reduction overshadows racking improvements (until now)
- First time paper on cost analysis of pv racking
- Design related to previous paper (3D printed + wire)
- 80% savings, increase of 33% power density; savings $0.01-$0.02/kWh
- potential PV rooftop installs hindered by over-designed racking & costs.
- cost analysis of design from X-wires design found in "3-D printing solar photovoltaic racking in developing world" paper above
Design of Post-Consumer Modification of Standard Solar Modules to Form Large-Area Building-Integrated Photovoltaic Roof Slates[edit | edit source]
Abstract: Building-integrated photovoltaic (BIPV) systems have improved aesthetics but generally cost far more than conventional PV systems because of small manufacturing scale. Thus, in the short and medium term, there is a need for a BIPV mounting system that utilizes conventional modules. Such a design is provided here with a novel modification of conventional photovoltaic (PV) modules to allow them to act as BIPV roofing slates. The open-source designs for the mechanical components necessary to provide the post-consumer conversion for a conventional PV module are provided, and prototypes are fabricated and installed on a mock roof system along with control modules mounted conventionally. The approximately U.S.$22/module BIPV roof-mounted system is direct mounted on the roof to eliminate the need for roofing shingles or other coverings, which effectively provides a 20% total cost reduction from conventional racking systems that demand a roof to mount upon without considering the savings from the rack itself. The results of the outdoor system testing found no water leaks. An increased operating temperature was observed, which would reduce the output from a silicon-based PV module by less than 10%. The results found significant potential for this design to further reduce total PV systems costs.
- PV modules drop US $0.50/W [1,2], LC pv electricity 6 cents/kWh 
- This design is USD22/module = 20% savings (vs conventional racking; 90% vs BIPV)
- Financing increasing accesibility [7–12].
- Some HOA ban PV 
- Smart BIPV expensive; design uses conventional module instead
- Avg op temp PV 50c; STC 25c; BIPV temp increase observed -sensor location
- See losses based on racking system, cooling/airflow (<10% reduced output in this case)
- open-source design of post-consumer modification of standard solar modules to form large-area BIPV.
- SMEs & mfg
- Data can be used life cycle cost analysis -need cost of materials and time of assembly/install.
Distributed manufacturing with 3-D printing: a case study of recreational vehicle solar photovoltaic mounting systems[edit | edit source]
Abstract: For the first time, low-cost open-source 3-D printing provides the potential for distributed manufacturing at the household scale of customized, high-value, and complex products. To explore the potential of this type of ultra-distributed manufacturing, which has been shown to reduce environmental impact compared to conventional manufacturing, this paper presents a case study of a 3-D printable parametric design for recreational vehicle (RV) solar photovoltaic (PV) racking systems. The design is a four-corner mounting device with the ability to customize the tilt angle and height of the standoff. This enables performance optimization of the PV system for a given latitude, which is variable as RVs are geographically mobile. The open-source 3-D printable designs are fabricated and analyzed for print time, print electricity consumption, mechanical properties, and economic costs. The preliminary results show distributed manufacturing of the case study product results in an order of magnitude reduction in economic cost for equivalent products. In addition, these cost savings are maintained while improving the functionality of the racking system. The additional electrical output for a case study RV PV system with improved tilt angle functionality in three representative locations in the U.S. was found to be on average over 20% higher than that for conventional mass-manufactured racking systems. The preliminary results make it clear that distributed manufacturing - even at the household level - with open-source 3-D printers is technically viable and economically beneficial. Further research is needed to expand the results of this preliminary study to other types of products.
- Transport major portion of env impact. Sources: (Zhu and Sarkis 2006; Pearce et al 2007; Cholette and Venkat 2009; Meisterling et al. 2009; Winnebeck 2011)
- 3D printers as environmentally sustainable due to this. Cites (Kreiger and Pearce 2013a, b)
- Terminology Open-Source self-replicating rapid prototypers (RepRap)
- Explains RepRaps
- Open-source approach to PV (Buitenhuis and Pearce 2012)
- Many PV on thingverse (Makerbot Thingverse 2012a, b, 2013a)
- Cost per watt dropped 80% in past 5 years (Barbose et al 2012)
- 3d printed plastic as opposed to aluminum on RVs.
- Benefit of angle customization for RV (Lewis 2987; Shu et al 2006; Calabro 2009; Mehleri et al 2010)
- Aluminum expensive (Renvu 2014)
- Paper summary: novel 3d printable design with angle adjustment tested in 3 locations.
- Methods starts discussing where stress occurs due to a bending moment
- Goes through calculation of this to derive design parameters
- Chose ABS plastic to resist environmental effects (Davis et al 2004)
- Printed parts can be treated with acetone
- Relative cost of racking inv. Proportional to PV size p.4
- Pearce 2002 on the intrinsic sustainability of PV
- King et al. 2014 on solar powered reprap
- Results: traditional aluminum total $75.23 total, 37.6 c/watt (Northern Arizona Wind & Sun 2014)
- 3D-Printed $7.21 total, 3.6 c/watt
- Added benefit of tilt-ability
- Added benefit of making system smaller
- Studies needed for longevity
- Not taken into account: RepRap unit and human labor.
- Assumption that reprap already owned personally for other household products
- Assumption that downloading stl file and using open source software is easy to use and user can walk away during printing
- Further study needed for LCA
PV Cell Technology, Tests, Design[edit | edit source]
Advances in Solar Photovoltaic Technology: An Applications Perspective[edit | edit source]
Abstract: Advances in photovoltaic module technology, inverters, system installation practices, and design standards are improving the performance of PV systems and have led to PV becoming established as a strongly competitive energy source for off-grid energy applications. PV is also on the cusp of becoming competitive in grid connected configurations and is currently experiencing strong growth in this type of application. Substantially reduced PV module cost and higher module efficiency compared to products of just a decade ago are playing a key role in this expansion. The introduction of modern inverters that are more efficient, have higher reliability, and improved utility system interface features are also facilitating market growth. In addition, experience gained from hundreds of thousands of PV installations over the past decade, as well as a maturing base of PV service providers, system integrators, and new industry design standards has led to improved designs and economies in the installation of PV systems. Overall, PV energy costs have fallen by a factor of about 2 over the past decade and the prospects for continued improvement are strong. This presentation reviews advances in PV technology and the role they are playing in its expansion.
- 15-40%/decade growth of PV usage globally @ 20-40 cents/kw-hr (1,2)
- Module cost = 25-50% of total cost
- Module density affects cost via BOS
- Increased cell efficiency (better PV technology) = <modules, <BOS (i.e. racking, installation, amplification accessories etc.)
- Racking adv: non- penetrating roof retrofit, labor free install, wind resistant & PV as multiple use (i.e. shade, BIPV) + 2ndary benefits (i.e. HVAC costs).
- Fed & state sponsored wind loading testing
- Table: value of PV advancements as reduction in "effective cost"
- $2.5-6/W cost of pv module + 6-12 with install at time of paper (2004)
- Lowering cost not dependent only on PV cell adv.
Dynamic thermal model of solar PV systems under varying climatic conditions[edit | edit source]
- Electrical performance depends on temperature and thus climate (Nagae et al., 2006)
- Temp inv proportional to output voltage => produced power (Skoplaki et al., 2008)
- Previous studies model temp based on env (Schott, 1985; Servant, 1985; Malik and Damit, 2003; Nordmann and Clavadetscher, 2003; Krauter, 2004; Franghiadakis and Tzanetakis, 2006; Mattiei et al., 2006; Chenni et al., 2007; Durisch et al., 2007, and Topic et al., 2007)
- These assume steady state
- Can't assume this during rapid fluctuation of irradiance (Jones and Underwood, 2001)
- Must take into account thermal mass of unit
- Paper extends previous thermal mass modeling work (Jones and Underwood, 2001; Notton et al., 2005; Mattiei et al., 2006; Balog et al., 2009; Armstrong and Hurley, 2010; Caluianu and Ba˘lta˘re_u, 2012, and Tsai and Tsai, 2012)
- Summary: paper presents dynamic thermal model of heat transfer mechanism and validated with experimental data from Tampere, Finland (Torres Lobera and Valkealahti, 2012)
- Displays energy balance equation (solar radiation in – power output – heat loss – time derivative of temperature times specific heat =0)
- Provides expressions for variables
- Specific heat of module is derived as sum depending on dimensions, density, and material of component parts
- Goes through more thermos derivation
- End of section 2 results in a time varying equation without analytical solution
- Analysis used three winter days and three summer days
- Discusses model results. Better agreement in winter than in summer-states more variability in summer.
- Also mentions heating of the back of the module at different times of day and not being measured separately increasing error of measurement
- Then goes into sensitivity analysis
A simple correlation for the operating temperature of photovoltaic modules of arbitrary mounting[edit | edit source]
Abstract: Following a brief discussion regarding the operating temperature of commercial grade silicon photovoltaic (PV) cells/modules and its effect upon the performance of free-standing one-sun PV installations, a simple semi-empirical explicit correlation for PV cell temperature and the corresponding efficiency form are proposed for modules of arbitrary mounting. To this end, a dimensionless mounting parameter, o, is introduced rendering the correlations suitable for systems like building-integrated photovoltaic (BIPV) array generators. The implications of ignoring radiation and free-convection are quantified and a comparison is made with analogous relations in the literature.
- Temperature affects operation by affecting electrical parameters (voltage and current)
- Temperature depends on angle of incidence
- Derives expression for efficiency as a function of temperature compared to a reference temperature and efficiency
- To lower temperature modules are designed to transport heat away from the panel, including through the mounting frame
- At steady state this just transports heat to surface to release as convection and radiation
- Derives equation for operating temperature based on thermal and physical properties, solar source and weather, and wind heat transfer
- Develops a model with assumption that both sides of module experience same ambient temperature which is based on assumption of free standing module and not BIPV
- Highly dependent on module area and angle of incidence, thus rigorous tests should be done to determine NOCT (Nominal Operating Cell Temperature)
- Decision of proper velocity affects the operating temperature of the module
- Convection must be taken into account as well
Investigation of the energy output from PV racks based on using different tracking systems in Amman-Jordan[edit | edit source]
Abstract: Solar energy is the promising renewable energy candidate in Jordan to cover the energy needs and to replace the traditional production ways of energy. The average solar radiation in Jordan is in between 4 and 8 KWh/m2 which make Jordan is a suitable location for solar investment. For that studying the possible ways to maximize solar energy production from the PV system is essential. This study comes to compare the outputs of solar panel racks driven by the horizontal single-axis tracker (HSAT), the vertical single-axis tracker (VSAT), and the altazimuth dual-axis trackers (AADAT), as well as that of a fixed solar panel rack.
- Study compares horizontal single-axis tracker (HSAT), vertical single-axis tracker (VSAT), and altazimuth dual-axis tracker (AADAT)
- P3 "…capacity of XX…"
- Uses Energy-3D simulation to analyze different tracking methods
- Derives tilt angle expression
- Compares fixed panel to various tracking methods and to each other
- incomplete study/paper
Performance Comparison of a BIPV Roofing Tile System in Two Mounting Configurations[edit | edit source]
Abstract: This paper examines the performance of a building integrated photovoltaic (BIPV) roofing system commonly available to residential markets. In particular polycrystalline Si PV roofing tiles were integrated with concrete roofing tiles in two mounting configurations being used by roofing contractors. In the first configuration the tiles were directly mounted to the roof sheeting allowing little to no airflow under the PV modules. In the second configuration furring strips were attached to the roof deck to create a counter-batten system to which the roofing and PV tiles mount. This counter-batten system provides an air gap between the roof deck and the PV/concrete tiles which allows for convective cooling. A complete data acquisition system was applied to both mounting configurations and they were monitored for a summer period in Golden, Colorado. A performance comparison is presented for the systems while both are gauged against freestanding rack-mounted polycrystalline Si PV modules. As expected, modules mounted directly to the deck operated at higher temperatures and produced less power than those on a counter-batten system while both systems operated at higher temperatures than rack mounted modules.
A Proposed Method of Photovoltaic Solar Array Configuration Under Different Partial Shadow Conditions[edit | edit source]
Abstract: The benefit of improving the efficiency of photovoltaic (PV) solar system has come into view because of increasing the demand for electricity, especially in the urban areas. However, these PV solar systems are vulnerable to the mismatch operating conditions. Under such conditions, the performance of solar cells has decreased rapidly since the nonuniform insolation hitting the cells and with different values. Then this leads to cause rapidly decreasing in the output power value and maximum power point, beside to hot spot points that may be occurring in the solar cell which finally leads to damage these cells. This paper proposes an optimal connection of substrings with different value of shadow conditions, based on a thorough configuration that can significantly reduce that nonuniform condition loss. The refinement over existing photovoltaic (PV) solar array interconnections is proven by extensive simulation results by using MATLAB SIMULINK. doi:10.4028/www.scientific.net/AMR.983.307.
Optimal Hybrid Array Configuration Scheme to Reduce Mismatch Losses of Photovoltaic System[edit | edit source]
Abstract: This paper proposes a hybrid array configuration technique to reduce mismatch losses in the photovoltaic (PV) array under partial shading condition. The reduction in PV array output power does not depend linearly on the shaded PV module, instead it is highly dependent on the extent of mismatch. The extend of mismatch depends upon several factors like type of configuration, array size and shading patterns. Here, different array configuration techniques like series-parallel (SP), total-cross-tied (TCT), bridge-linked (BL), honey-Comb (HC) along with a new hybrid array configuration technique have been discussed to contemplate the effects of mismatch conditions. A comparative analysis is being accomplished using different irradiance test conditions for determining the configuration having lowest amenability to power loss under mismatch condition. doi:10.1109/ICECCT.2017.8117990.
Optimal Configuration for Design of Stand-Alone PV System[edit | edit source]
Abstract: This paper presents a design for a stand-alone photovoltaic (PV) system to provide the required electricity for a single residential household in rural area in Jordan. The complete design steps for the suggested household loads are carried out. Site radiation data and the electrical load data of a typical household in the considered site are taken into account during the design steps. The reliability of the system is quantified by the loss of load probability. A computer program is developed to simulate the PV system behavior and to numerically find an optimal combination of PV array and battery bank for the design of stand-alone photovoltaic systems in terms of reliability and costs. The program calculates life cycle cost and annualized unit electrical cost. Simulations results showed that a value of loss of load probability LLP can be met by several combinations of PV array and battery storage. The method developed here uniquely determines the optimum configuration that meets the load demand with the minimum cost. The difference between the costs of these combinations is very large. The optimal unit electrical cost of 1 kWh for LLP = 0.049 is $0.293; while for LLP 0.0027 it is $0.402. The results of the study encouraged the use of the PV systems to electrify the remote sites in Jordan. doi:10.4236/sgre.2012.32020
- Structural Loading
- Wind loads
- Debris accumulation
- Fire Hazards
- Electrical Hazards
- Best Practices
- Hazard Gap Analysis
Model of Loss Mechanisms for Low Optical Concentration on Solar Photovoltaic Arrays with Planar Reflectors[edit | edit source]
Abstract: The use of low optical concentration with planar reflectors represents a relatively simple method for improving solar photovoltaic (PV) specific efficiency. A coupled optical and thermal model was developed to determine the effects on yearly performance of a planar concentrator on array-scale solar PV installations. This model accounts for i) thermal, ii) angle of incidence, iii) reflectivity, and iv) string mismatch loss mechanisms in order to enable informed design of low optical concentration systems. A case study in Canada is presented using the model and the simulation results show that a planar reflector system installed on a traditional crystalline silicon-based PV farm can produce increases in electrical yield from 23-34% compared to a traditional optimized system and thus represents a potential method of achieving practical gains in PV system yield.
- Low optical concentration + planar reflector => improve specific efficiency
- More detailed model takes into account thermal, angle of incidence, reflectivity, and string mismatch loss mechanisms
- Case study in Canada using model
- Electrical yield increase 23-34%
- Cost of module is half cost of total system => make efficient use of PV system to reduce cost
- Metric: specific efficiency (SE) = produced energy per installed rated power
- Comparison to stationary solar array, low SE low balance of systems (BOS), low O&M cost
- Tracking has higher SE, higher initial BOS, continuing O&M cost
- Optical concentration, higher SE. Solar insolation falling around system concentrated onto system
- Low concentration systems, increase incident insolation <10X
- Includes three kinds: compound parabolic, V-trough, flat planar
- Flat planar increase concentration and relatively inexpensive
- Conventional northern hemisphere array: east-west rows of southern facing panel
- At solar noon energy not captured in spaces between arrays. Solution: solar concentrators
- More detailed model of planar concentrators to analyze loss mechanisms
- Assumption: can be modeled in 2d
- For PV tech or module independence, electrical output of system not calculated
- Insolation calculated
- System oriented at optimal angle
- Developed in matlab
- 5 cases depending on shading
- Factors taken into account for modeling: total insolation on panel surface, angle of incidence, panel temperature, spectral distribution, string mismatch, reflection loss
- Temp decreases voltage (21) JJ Wysocki, P Rappaport, Effect of temperature on photovoltaic solar energy conversion. Journal of Applied Physics, 31(3):571–578, 2009 Long term degradation if temp exceeds a limit (22) A Royne, CJ Dey, DR *Mills, Cooling of photovoltaic cells under concentrated illumination: a critical review. Solar Energy Materials and Solar Cells 86(4):451–483,2005
- AOI losses due to reflection. Relationship of angle to efficiency based on test at Sandia labs and modeled by a 6th degree polynomial
- String mismatch: non uniform sell insolation. Due to variation in manufacture tolerance, environmental stress, and shadowing.
- Shading can have significant effects and even lead to module failure
- Tilt angles varied from 20 to 90 degrees
- AOI losses respond to panel angle and row spacing
Abstract: A non-sun-tracking concentrating solar module is described that is designed to achieve photovoltaic (PV) systems with higher generation power density. The proposed concentrating module consists of a solar panel having a higher tilt angle than that of a conventional one and with a solar reflector placed in front of the solar panel on a downward inclination angle towards the panel. As a result of this configuration, the solar panel receives reflected as well as direct sunlight so that maximum irradiance and short-circuit current were increased. This configuration is expected to reduce the area required for solar panels, resulting in lower cost PV system. Non-sun tracking
- Designed to achieve higher generation power density
- Changes in angle and addition of a mirror to result in smaller PV panels lowering costs
- Concentration without lenses or tracking which are expensive
- Higher tilt angle of any solar panel plus a horizontal mirror
- Characteristic tests tested in artificial sunlight in a lab and actual sunlight outside
- Tested for effects of inclination angle
Wind Loads & Tests[edit | edit source]
Wind Design Practice and Recommendations for Solar Arrays on Low-Slope Roofs[edit | edit source]
Abstract: Currently, ASCE standards do not provide specific guidance on wind loads for solar arrays of photovoltaic panels, in terms of either prescriptive design or requirements for wind tunnel testing. Guidance is needed, particularly for arrays of low-profile tilted panels on flat or low-slope roofs, because they are markedly different aerodynamically from structures currently addressed in the building code. This paper presents recommendations for the structural design of these solar arrays for wind-loading. Recommendations include (1) categorizing solar array support-systems according to their height above the building roof and how they distribute forces to the roof, (2) developing pressure coefficients that are applicable to structurally interconnected roof-bearing support systems, (3) considering load cases that include uniform wind pressure on the array and nonuniform (gust) patterns, (4) determining appropriate stiffness and boundary conditions for structural analysis, and (5) use of testing to verify behavior and calibrate analytical models. DOI: 10.1061/(ASCE)ST.1943-541X.0000806
Wind Loads on Low-Profile, Tilted, Solar Arrays Placed on Large, Flat, Low-Rise Building Roofs[edit | edit source]
Abstract: The author examined wind loads on low-profile, roof-mounted solar arrays, placed on large, low-rise buildings with nearly flat roofs by using scale models in a boundary layer wind tunnel. The author also examined the effects of building size and array geometry on enveloping curves of area-averaged pressure coefficients, typical of use for design. It was found that wind loads on the array increase with building size; normalizing the effective wind area by the building wall size leads to enveloping curves that collapse onto a single curve for each array geometry. For tilt angles less than 10°, there is an approximate linear increase in the pressure coefficients as the tilt angle increases. For arrays with tilt angles of 10° or more, the wind loads do not depend significantly on the tilt angle and are relatively constant. Roof zones for wind loads on solar arrays are larger than roof zones for bare roofs and depend on the array tilt angle. DOI: 10.1061/(ASCE)ST.1943-541X.0000825
Use of the Wind Tunnel Test Method for Obtaining Design Wind Loads on Roof-Mounted Solar Arrays[edit | edit source]
Abstract: ASCE 7 does not provide design wind loads for roof-mounted solar panels. This paper discusses the use of the wind tunnel test method, called Method 3 in ASCE 7-05, which was originally intended for obtaining design wind loads for individual buildings. Because roof-mounted solar arrays are generally mounted in many configurations on many buildings of many different shapes, additional requirements are necessary to use Method 3 in this situation. The paper describes these additional requirements. DOI: 10.1061/(ASCE)ST.1943-541X.0000654
Wind loading characteristics of solar arrays mounted on flat roofs[edit | edit source]
Abstract: With the increasing use of solar photovoltaics, wind-induced loads on rooftop solar arrays have become a problem. A series of wind tunnel experiments have been performed to evaluate wind loads on solar panels on flat roofs, mainly focusing on module forces calculated from area-averaged net pressures on solar modules of a standard size. In order to investigate the module force characteristics at different locations on the roof, solar array models, which were fabricated with pressure taps installed as densely as possible, were moved from place to place. Design parameters including tilt angle and distance between arrays, and building parameters including building depth and parapet height, have also been considered. The results show that unfavorable negative module force coefficients for single-array cases are much larger than those for multi-array cases; tilt angle and distance between arrays increase negative module forces; effects of building depth and parapet height on negative module forces are not obvious; and recommendation values in JIS C 8955 Standard correctly estimate negative mean module force coefficients but not peak values. https://doi.org/10.1016/j.jweia.2013.08.014Get rights and content
Wind Turbulence and Load Sharing Effects on Ballasted Roof-Top Solar Arrays[edit | edit source]
Abstract: This collection contains 106 papers presented at the ATC & SEI Conference on Advances in Hurricane Engineering, held in Miami, Florida, October 24-26, 2012. When Hurricane Andrew wreaked havoc on South Florida and Louisiana 20 years ago, the engineering community learned a great deal about how powerful storms affect the built environment. These papers demonstrate the application of lessons learned to reduce losses from subsequent hurricanes and to make communities more resilient to natural hazards.
- Wittbrodt, Ben, and Pearce, Joshua M. "3-D Printing Solar Photovoltaic Racking in Developing World." Energy for Sustainable Development, vol. 36, Elsevier Inc., Feb. 2017, pp. 1–5, doi:10.1016/j.esd.2016.08.001.
- Wills, Rosalie, et al. Best Practices for Commercial Roof-Mounted Photovoltaic System Installation. Springer, 2015.
- Andrews, Rob W., Nabeil Alazzam and Joshua M. Pearce. Model of Loss Mechanisms for Low Optical Concentration on Solar Photovoltaic Arrays with Planar Reflectors. Ontario: Queen's University, n.d.
- Matsushima, Toshio, Tatsuyuki Setaka and Seiichi Muroyama. "Concentrating solar module with horizontal reflectos." Solar Energy Materials & Solar Cells (2003): 603-612.