Engineering Commons^™

Automated Solar-Powered Chicken Coop Door, Brenna Yagade

Computer Engineering

The purpose of this project was to plan, design, and build an automated, low power system to open and close a chicken-coop door, which is powered through a solar panel.

Minimizing Sheet Resistance Of Organic Photovoltaic Cell Top Contact Electrode Layer: Silver Nanowire Concentration Vs. Conductive Polymer Doping Concentration, Caitlyn Cook

Materials Engineering

The top contact electrode layers of nine organic photovoltaic cells were prepared with two varying factors: three Silver nanowire (AgNW) densities deposited on a conductive polymer doped with three concentrations. Silver’s low sheet resistance of 20-Ω/sq is hypothesized to lower the sheet resistance of the anode layer and thus enhance the overall efficiency of the cell. Four-point probe measurements indicated that increasing AgNW density in the top contact electrode layer of an organic photovoltaic cell significantly reduces sheet resistance from 52.2k-Ω/sq to 18.0 Ω/sq. Although an increase in doping concentration of the conductive polymer reduced sheet resistance in low AgNW …

Solar Decathlon Instrumentation And Controls, Timothy Ambrose, Mateo Begue, Andrew Elliott

Mechanical Engineering

The Instrumentation and Controls team has designed a control and instrumentation system for the 2015 Cal Poly Solar Decathlon house that will monitor temperature, humidity, and energy usage throughout the house and control the phase change material duct. It will relay information to the user through a tablet application developed by the Computer Science team. The team has also designed a lighting control scheme for use with Lutron’s HomeWorks QS lighting control system.

Solar Evaporative Fan Coil Unit, Jeremy Dickson, Sam Budnick, Kyle Kluever

Mechanical Engineering and Technology Senior Projects

The purpose of any engineering project is to anticipate a need and meet that need through prediction analysis and design. Over 70% of the nation’s energy is consumed by building infrastructure such as HVAC systems, electrical, etc. HVAC systems use boilers to generate hot water or steam to heat buildings and chillers to provide cold water for cooling. The overall solar evaporative fan coil unit project involves the design and construction of a system that will heat and cool air using a solar collector and an evaporative chiller. This report covers the design and construction of the evaporative chiller specifically. …

Hybrid Fuzzy-Pid Controller For Buck-Boost Converter In Solar Energy-Battery Systems, Karime Farhood Hussein

Masters Theses

In the present work, we propose a hybrid fuzzy PID control system to prevent overshoot and oscillations in DC-DC buck-boost converter for solar-battery system. We design and simulate a PID, a Fuzzy logic controller, and hybrid fuzzy PID control system to stabilize the output voltage of the buck-boost converter. The performance results using dynamic response of all of these controllers in terms of rise time, overshoot, peak time, and voltage oscillation are presented. The simulation results support the validity and advantages of the hybrid method.

Power Sharing Among Multiple Solar Photovoltaic (Pv) Systems In A Radial Distribution Feeder, Brian K. Perera, Philip Ciufo

Dr Philip Ciufo

With an increasing penetration of solar photovoltaic (PV) systems, power distribution grids are becoming more susceptible to network voltage rise. As per applicable standards for grid-integrated PV systems, a PV system must be automatically disconnected from the grid when the terminal voltage of the PV system exceeds a defined maximum voltage. With this directive, in certain situations, PV systems connected at nodes at which the voltage sensitivity is high, may be disconnected from the grid while PV systems connected at less sensitive nodes are continuing to operate. In such a situation, owners whose PV systems are connected at nodes at …

Solar Pv And Battery Storage Integration Using A New Configuration Of A Three-Level Npc Inverter With Advanced Control Strategy, Hamid Teymour Ghasemabadi, Danny Soetanto, Kashem M. Muttaqi, Philip Ciufo

Dr Philip Ciufo

In this paper, a novel configuration of a three-level neutral-point-clamped (NPC) inverter that can integrate solar photovoltaic (PV) with battery storage in a grid-connected system is proposed. The strength of the proposed topology lies in a novel, extended unbalance three-level vector modulation technique that can generate the correct ac voltage under unbalanced dc voltage conditions. This paper presents the design philosophy of the proposed configuration and the theoretical framework of the proposed modulation technique. A new control algorithm for the proposed system is also presented in order to control the power delivery between the solar PV, battery, and grid, which …

Point Of Common Coupling (Pcc) Voltage Control Of A Grid-Connected Solar Photovoltaic (Pv) System, Brian K. Perera, Philip Ciufo, Sarath Perera

Dr Philip Ciufo

In future low voltage grids, with multiple inverter interfaced sources connected, voltage regulation may become a necessary task. The potential exists for inverter interfaced sources to be deployed to regulate the voltage at the point of common coupling (PCC) of each inverter interfaced sources. The PCC voltage regulation is attainable with inverter interfaced sources by dynamically controlling the amount of reactive power injected to the power distribution grid by individual systems. In the current research, a closed-loop controller is proposed to regulate the PCC voltage of a solar photovoltaic (PV) system that is connected to a single-phase power distribution feeder …

Smart Solar Oven, Aaron Gragg

Computer Engineering

Though solar oven technology provides a green and cost effective means of cooking, it is often not adopted because it fails to meet the demands of speed and reliability that are commonplace in our society. This project explores the modification of a traditional box solar to meet these demands by allowing the oven to report temperature to a user’s phone as well as orient itself towards the sun throughout the day.

Syllabus: Solar Energy Systems And Building Design, Ho-Sung Kim

Sustainability Education Resources

This course introduces the fundamental concepts of solar building design and energy systems. Through project based study and possible field visits, students will explore the theory, technologies, applications, and benefits of solar design of buildings and discover how to utilize solar energy systems for residential and commercial buildings. Students will be required to research and document technology and complete a semester case study project in which they will examine various energy conservation aspects and economics underlying solar energy systems.

A Bi-Layer Tio2 Photoanode For Highly Durable, Flexible Dye-Sensitized Solar Cells, Jianjian Lin, Yong Peng, Alexander Pascoe, Fuzhi Huang, Yi-Bing Cheng, Yoon-Uk Heo, Andrew Nattestad, Wanchul Seung, Sung Kyun Kim, Hoon Joon Yoon, Sang Woo Kim, Yusuke Yamauchi, S X. Dou, Jung Ho Kim

Australian Institute for Innovative Materials - Papers

Low-temperature processing of dye-sensitized solar cells (DSCs) [B. Oregan, M. Grätzel, Nature, 1991, 353, 737] is crucial to enable their commercialization with low-cost plastic substrates. Much of the previous work in this area has focused on mechanical compression of premade particles on plastic substrates; however, many reported that this technique did not yield sufficient interconnections for high charge carrier transport. Herein, we present bi-layer photoanodes that incorporate microstructured TiO₂ sea-urchin-like assemblies, composed of high-aspect-ratio single crystalline nanoribbons, i.e., two-dimensional subunits, which were deposited onto a nanoparticle layer (commercial P25), with a 5.6% conversion efficiency realized. We demonstrate that …

Enhanced Electron Lifetime Of Cdse/Cds Quantum Dot (Qd) Sensitized Solar Cells Using Znse Core-Shell Structure With Efficient Regeneration Of Quantum Dots, Rasin K. Ahmed, Long Zhao, Attila J. Mozer, Geoffrey D. Will, John M. Bell, Hongxia Wang

Australian Institute for Innovative Materials - Papers

Research on development of efficient passivation materials for high performance and stable quantum dot sensitized solar cells (QDSCs) is highly important. While ZnS is one of the most widely used passivation material in QDSCs, an alternative material based on ZnSe which was deposited on CdS/CdSe/TiO₂ photoanode to form a semi-core/shell structure has been found to be more efficient in terms of reducing electron recombination in QDSCs in this work. It has been found that the solar cell efficiency was improved from 1.86% for ZnSe0 (without coating) to 3.99% using 2 layers of ZnSe coating (ZnSe2) deposited by successive ionic …

An Intermediate Band Dye-Sensitised Solar Cell Using Triplet-Triplet Annihilation, Catherine Simpson, Tracey M. Clarke, Rowan W. Macqueen, Yuen Yap Cheng, Adam J. Trevitt, Attila J. Mozer, Pawel W. Wagner, Timothy W. Schmidt, Andrew Nattestad

Australian Institute for Innovative Materials - Papers

A new mechanism of charge photogeneration is demonstrated for the first time, based on organic molecular structures. This intermediate band approach, integrated into a dye-sensitised solar cell configuration is shown to generate charges upon illumination with low energy photons. Specifically 610 nm photoexcitation of Pt porphyrins, through a series of energy transfer steps and triplet-triplet annihilation, excites a higher energy absorption onset molecule, which is then capable of charge injection into TiO2. Transient absorption measurements reveal further detail of the processes involved.

Community Energy Storage For Neutral Voltage Rise Mitigation In Four-Wire Multigrounded Lv Feeders With Unbalanced Solar Pv Allocation, Md Jan E Alam, Kashem M. Muttaqi, Danny Sutanto

Faculty of Engineering and Information Sciences - Papers: Part A

The traditional neutral voltage problem in low-voltage (LV) four-wire multigrounded distribution networks can be aggravated due to an unbalanced allocation of one-phase photovoltaic (PV) units. Inherent limitations restrict the performance of the traditional strategies to mitigate the combined effect of load and PV unbalance. To overcome the shortcoming of traditional approaches, a new dynamic mitigation approach using community energy storage (CES) is proposed in this paper. A power balancing algorithm is developed to perform the balancing operation while minimizing power drawn from the CES. A charge/discharge control strategy is developed that will continuously balance and dynamically adjust the power exchange …

Performance Analysis And Modelling Of Hybrid Photovoltaic-Thermal Solar Panels, Nicole C. Annis

Doctoral Dissertations

A photovoltaic-thermal (PVT) panel was constructed, tested, and modelled using both MATLAB and TRNSYS. During the experimental testing, which took place on the Missouri University of Science and Technology campus in Rolla, Missouri; two identical PVT panels were tested alongside two PV panels to gather an electrical baseline for comparison. Approximately 69 days’ worth of data were of data were collected during the summer of 2014. The PV electrical, PVT electrical, PVT thermal and PVT combined (electrical and thermal) efficiencies were 3.5-5.6%, 3.4-5.4%, 20.9-11.6%, and 24.3-17.0%, respectively.

A MATLAB program was developed using existing equations for one-dimensional, quasi-steady model of …

Absorption Enhancement In Double-Sided Nanocone Hole Arrays For Solar Cells, Xu Zhang, Yanguang Yu, Jiangtao Xi, Yile Wang, Xiao-Hong Sun

Faculty of Engineering and Information Sciences - Papers: Part A

Enhancing light absorption in thin-film silicon solar cells is important for improving light harvesting efficiency and reducing manufacture cost. In this paper, we introduce a double-sided nanocone hole (NCH) array structure for solar cells by extending a model suggested by Wang et al (2012 Nano Lett. 12 1616). The top-sided NCH structure is mainly used for increasing the antireflection of incident light, and the bottom-sided NCH structure for enhancing light trapping in the near-infrared spectrum. The theoretical analysis is performed on the proposed structure, from which the optimal geometric parameters of the structure are determined. The performance analysis shows that …

Using Solar Photovoltaic Thermal Collectors In Phase Change Materials Enhanced Buildings For Thermal Performance Management, Zhenjun Ma, Wenye Lin, Mohammed I. Sohel

Faculty of Engineering and Information Sciences - Papers: Part A

This paper presents the investigation of using air-based solar photovoltaic thermal (PVT) collectors in phase change materials (PCMs) enhanced buildings for effective thermal management. PVT collectors are used to generate electricity and provide low grade heating energy to buildings for winter space heating. PCMs are either integrated into building walls to increase the local thermal mass or used as a temporary centralized thermal storage to store the low grade thermal energy derived from the PVT collectors. The thermal performance of buildings due to the integration of the PVT collectors and PCMs is tested and evaluated through computer simulations. It is …

A Versatile Binder-Free Tio2 Paste For Dye-Sensitized Solar Cells, Jeremy H. Yune, Inna Karatchevtseva, P Evans, Klaudia K. Wagner, Matthew J. Griffith, David L. Officer, Gerry Triani

Australian Institute for Innovative Materials - Papers

In this study, binder-free TiO₂ colloidal pastes have been prepared using a variety of heterocyclic bases with diverse characteristics to produce robust photoanodes for dye-sensitized solar cells (DSSC) from a single cast film thickness of 5 micron. The influence of the base on the electrode structure and film morphology, including its electron donor characteristics are investigated after low temperature thermal treatment and high temperature sintering. The results show that quinoline in the TiO₂ paste is retained within the electrode structure in comparison to piperidine and pyridine after a short thermal treatment of 150 °C for 15 minutes. The …

Enhanced Electron Lifetimes In Dye-Sensitized Solar Cells Using A Di-Chromophoric Porphyrin: The Utility Of Inter-Molecular Forces, Long Zhao, Pawel W. Wagner, Holly Van Der Salm, Keith C. Gordon, Shogo Mori, Attila J. Mozer

Australian Institute for Innovative Materials - Papers

Electron lifetimes in dye-sensitized solar cells employing a porphyrin dye, an organic dye, a 1:1 mixture of the two dyes and a di-chromophoric dye design consisting of the two dyes using a non-conjugated linker were measured, suggesting that the dispersion force of the organic dyes has a significant detrimental effect on the electron lifetime and that the di-chromophoric design can be utilized to control the effect of the dispersion force.

Increased Upconversion Performance For Thin Film Solar Cells: A Trimolecular Composition, Yuen Yap Cheng, Andrew Nattestad, Tim F. Schulze, Rowan W. Macqueen, Burkhard Fückel, Klaus Lips, Gordon G. Wallace, Tony Khoury, Maxwell J. Crossley, Timothy W. Schmidt

Australian Institute for Innovative Materials - Papers

Photochemical upconversion based on triplet-triplet annihilation (TTA-UC) is employed to enhance the short-circuit currents generated by two varieties of thin-film solar cells, a hydrogenated amorphous silicon (a-Si:H) solar cell and a dye-sensitized solar cell (DSC). TTA-UC is exploited to harvest transmitted sub-bandgap photons, combine their energies and re-radiate upconverted photons back towards the solar cells. In the present study we employ a dual-emitter TTA-UC system which allows for significantly improved UC quantum yields as compared to the previously used single-emitter TTA systems. In doing so we achieve record photo-current enhancement values for both the a-Si:H device and the DSC, surpassing …

Mesoporous Hierarchical Anatase For Dye-Sensitized Solar Cells Achieving Over 10% Conversion Efficiency, Jianjian Lin, Yoon-Uk Heo, Andrew Nattestad, Yusuke Yamauchi, S X. Dou, Jung Ho Kim

Australian Institute for Innovative Materials - Papers

Interest in both one-dimensional and hierarchical architectures of metal oxide semiconductors has intensified within the field of materials science over recent years. Herein, a new mesoporous anatase TiO₂ architecture that combines these two concepts, as it is composed of individual, high-aspect-ratio, nanoribbon-like components, was synthesized via a facile hydrothermal method without any surfactant or template. An 8.3% solar-to-electric conversion efficiency was obtained when these structures were used in photoanodes for dye-sensitized solar cells, which are superior to commercial state-of-the-art TiO₂ (6.6%), due to enhanced dye loading and efficient light scattering. To further improve the light scattering effect, a …

N719- And D149-Sensitized 3d Hierarchical Rutile Tio2 Solar Cells - A Comparative Study, Jianjian Lin, Yoon-Uk Heo, Andrew Nattestad, Mohammed Shahabuddin, Yusuke Yamauchi, Jung Ho Kim

Australian Institute for Innovative Materials - Papers

Poor dye loading on rutile TiO₂ is one of the chief reasons for lower solar-to-electric conversion efficiency (η) in dye-sensitized solar cells (DSCs), compared to their anatase based counterparts. Previously, we showed that similar light harvesting for both rutile and anatase was realized by using a metal-free organic indoline dye, D149 [Sci. Rep., 2014, 4, 5769]. This was in contrast to the bulk of previous studies, which employed ruthenium based N719, leading to significant differences in light harvesting. To date, there has been no report directly comparing N719 and D149 for rutile based DSCs. In this work, three-dimensional hierarchical …

Boosting The Efficiency Of Quantum Dot Sensitized Solar Cells Up To 7.11% Through Simultaneous Engineering Of Photocathode And Photoanode, Yang Bai, Chao Han, Xinqi Chen, Hua Yu, Xu Zong, Zhen Li, Lianzhou Wang

Australian Institute for Innovative Materials - Papers

We demonstrate a new strategy of boosting the efficiency of quantum dot sensitized solar cells (QDSSCs) by engineering the photocathode and photoanode simultaneously. Nanostructured photocathodes based on non-stoichiometric Cu_2-xSe electrocatalysts were developed via a simple and scalable approach for CdS/CdSe QDs co-sensitized solar cells. Compared to Cu₂S CE, remarkably improved photovoltaic performance was achieved for QDSSCs with Cu_2-xSe CEs. The superior catalytic activity and electrical conductivity of Cu_2-xSe CEs were verified by the electrochemical impedance spectra and Tafel-polarization measurements. To maximize the efficiency enhancement, the photoanodes were optimized by introducing a pillared …

Trap-Assisted Transport And Non-Uniform Charge Distribution In Sulphur-Rich Pbs Colloidal Quantum Dot-Based Solar Cells With Selective Contacts, Victor Malgras, Guanran Zhang, Andrew Nattestad, Tracey M. Clarke, Attila J. Mozer, Yusuke Yamauchi, Jung Ho Kim

Australian Institute for Innovative Materials - Papers

This study reports evidences of dispersive transport in planar PbS colloidal quantum dots heterojunction-based devices as well as the effect of incorporating a MoO3 hole selective layer on the charge extraction behavior. Steady state and transient characterization techniques are employed to determine the complex recombination processes involved in such devices. The addition of a selective contact drastically improves the device efficiency up to 3.15 % (especially through the photocurrent and series resistance) and extends the overall charge lifetime by suppressing the main first-order recombination pathway observed in device without MoO3. The lifetime and mobility calculated for our sulphur-rich PbS-based devices …

Stand-Alone Solar-Pv Hydrogen Energy Systems Incorporating Reverse Osmosis, Daniel Clarke

Theses: Doctorates and Masters

The world’s increasing energy demand means the rate at which fossil fuels are consumed has increased resulting in greater carbon dioxide emissions. For many small (marginalised) or coastal communities, access to potable water is limited alongside good availability of renewable energy sources (solar or wind). One solution is to utilise small-scale renewably powered stand-alone energy systems to help supply power for everyday utilities and to operate desalination systems serving potable water (drinking) needs reducing diesel generator dependence. In such systems, on-site water production is essential so as to service electrolysis for hydrogen generation for Proton Exchange Membrane (PEM) fuel cells. …