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Since the development and optical study of conjugated (conducting) polymers it has become apparent that chain conformation and aggregation at the molecular scale result in complex heterogeneous nanostructured bulk materials for which a detailed insight into morphological, spectroscopic as well as optoelectronic properties and mechanisms is overwhelmingly difficult to obtain. Nanoparticles composed of the conjugated polymer poly (MEH-PPV) and nanocomposite nanoparticles consisting of MEH-PPV doped with 1-(3-methoxycarbonylpropyl)-1-phenyl-C61 (PCBM) were prepared as model systems to study these materials at the length scale of one to a few domains. The MEH-PPV and PCBM doped nanoparticles were analyzed by single imaging/particle spectroscopy (SPS) and revealed molecular scale information on the structure-property relationships of these composite materials. The data obtained from SPS were investigated in terms of spectral difference between doped and undoped nanoparticles. The doped nanoparticles are blue shifted by approximately 5-10 nm, have an additional blue shoulder, and show different vibronic structure than the undoped nanoparticles. Specifically, relative intensity of the 0-1 transition is lower than for the undoped nanoparticles. These data are indicative of differences in molecular order between both nanoparticle systems, detected at the molecular scale. In addition, the effect of electrical fields present in devices on the interfacial charge transfer properties was evaluated. Furthermore, these nanoparticles were incorporated into the lipid nanotubes to study the diffusion process of the single MEH-PPV nanoparticles inside the lipid nanotubes. Our data shows a clear proof of concept that diffusion of nanoparticles inside the hollow lipid nanotubes can be studied on a single particle basis, which will allow us to study diffusion processes quantitatively and mechanistically within the framework of developing a biocompatible drug and gene delivery platform.

The growing popularity of photovoltaic (PV) generation systems leads to an increase in the number of residential and commercial grid-tied PV systems that interconnect to the distribution circuit. This affects the characteristics of the distribution circuit; for example, the assumption that the voltage profile of a radial line decreases down-stream becomes invalid because of the addition of the PV system on the line. This poses new challenges when setting the parameters of voltage regulating devices. Add to that the fact that PV systems are intermittent, especially on cloudy days, which make the line even more difficult to regulate, and the number of switching occurrences of the regulating devices increases, thus accelerating wear-and-tear to the utility’s equipment. The objective of this thesis is to develop an index which qualitatively indicates the impact of PV system(s) on operation, efficiency, reliability, and lifetime of voltage regulation equipment. Tests on the proposed index will be performed on several cases including circuits containing state-of-the art methods that integrate PV systems with minimum impact to utility equipment. Investigation of methods to further mitigate equipment wear by selecting the best interconnect point on the circuit will also be conducted to test the proposed index. The development and validation of the proposed index will entail power system modeling and simulation of distributed generation using PSCAD. The proposed index resulted from this study will provide a useful tool to allow utility companies pick the optimum locations for distributed generation to minimize their negative impact on the distribution lines as well as to determine the need for extra mitigation equipment.

Lack of access to information on the cost and timeframe for the permitting and interconnection of distributed renewable energy generation facilities may hinder renewable energy capacity development. This issue is examined within the specific context of solar photovoltaic systems developed for participation in the Feed-in Tariff (FIT) program hosted by the Marin Energy Authority (MEA). A guide on the permitting and interconnection of solar PV generators for participation in the program was produced for the host agency. This guide seeks to assist property owners and solar developers in overcoming existing informational challenges. By providing an overview of the procedural requirements and process, as well as reference tools that highlights helpful resources and documents, the guide provides readers with an introductory tool for overcoming existing non-market barriers to participation in the MEA FIT program. In addition, a Recommendations Report has also been produced to provide the MEA with a discussion of existing procedural challenges faced by program participants. This report, which details the issues identified by those stakeholders that participated in the development of the guide, concludes with a series of recommended actions that the MEA may take to enhance the ability of potential FIT participants to accurately estimate and plan for the costs and timeframes associated with permitting a solar PV facility.

As the ‘green’ energy movement continues to gain momentum, photovoltaic generation is becoming an increasingly popular source for new power generation. The primary focus of this paper is to demonstrate the benefits of close-to real-time cloud sensing for Photovoltaic generation. In order to benefit from this close-to real-time data, a source of cloud cover information is necessary. This paper looks into the potential of point insolation sensors to determine overhead cloud coverage. A look into design considerations and economic challenges of implementing such a monitoring system is included. The benefits of cloud location sensing are examined using computer simulations to target important time-scales and options available to plant operators. Finally, the economics of advanced forecasting options will be examined in order to determine the benefit to plant operators.

CONSTRUCTING AND OPTIMIZING A SINGLE WAFER SOLAR CELL ARRAY IN THE MICROFABRICATION LAB AT CALIFORNIA POLYTECHNIC STATE UNIVERSITY AT SAN LUIS OBISPO Solar cells are more and more becoming a significant source of energy in the world today. They are used to power entire buildings as well as small devices and everything in between, and are utilized all around the world. Smaller solar devices, such as hearing aid battery chargers, cost a lot of money relative to the monetary wealth in third-world countries. For this purpose, a less expensive, more efficient solar cell array should be developed. This study contains research that details all aspects of how solar cells work. It also details three years’ worth of studies at California Polytechnic State University (Cal Poly) that attempt to fabricate a solar cell array on a single wafer. Two tests were carried out that will help determine the optimal attributes of the solar cells. The first compared a solar cell made on a 10 µm thick silicon on insulator (SOI) wafer to solar cells made with the exact same masks on a 500 µm thick wafer. The thicker solar cell had 2.5 times the maximum power as the SOI solar cell. Aspects of the solar cell that would need to be improved are: increase thickness to between 70-100 µm from the SOI thickness, texture the front surface, add a passivation layer on the front surface, decrease the contact resistance for the metal electrodes, and add in a rear reflector. The next test was all about analyzing the metal contacts and interconnects. Ten gold-silver filled epoxy-gold bonds were constructed and measured ten times each, giving a grand mean between 10 and 11 Ω. Another short test was run with a commercial solar cell to characterize the change in power based on the series resistance. It was discovered that the both the epoxy and the gold add too much to the resistance. To fix this, a silver solder-like paste and a thicker contact metal should be used. There is also a derivation that details the design of a top contact layer that optimizes the finger spacing and finger width based on other solar cell factors. With the materials available at Cal Poly, a solar cell array can be fabricated on a single wafer. When accounting for the materials and processes available to the scientific community as a whole, a very effective and efficient solar cell can be fabricated.

Applications, converter topologies, and control schemes are examined for superconductive magnetic energy storage (SMES) systems. Diurnal load leveling for electric utilities and compensation for fluctuations in photovoltaic (PV) power generation are the primary applications discussed. It is demonstrated that a SMES system implemented with standard AC/DC converters offers energy storage capacity large enough, and dynamic response fast enough, to compensate for PV fluctuations due to changes in weather conditions. The method of control is developed so that the charging and discharging of the SMES system are changed in response to PV fluctuations, and the combined SMESIPV power output is smooth and controllable. An innovative control scheme is introduced for SMES that can simultaneously regulate real power and voltage independently without hardware modifications to the standard ACIDC bridge arrangement normally used for coordinated control of real and reactive power. The combination of SMES and PV systems could benefit from DCIDC converters that take advantage of the DC nature of both. It is established that DClDC converters can respond with sufficient speed to handle variations in PV power. A converter topology is devised where two DC/DC converters in cascade effectively maintain a PV array at its maximum power point and simultaneously control a SMES system to compensate for PV fluctuations. An alternative cascade configuration of an AC/DC converter with a DCIDC converter is proposed that could significantly reduce the reactive power requirements and improve the operational characteristics of a large scale SMES system connected to the utility grid. / Master of Science

This thesis proposes a new maximum power point tracking (MPPT) method for photovoltaic (PV) systems using Kalman filter. The Perturbation & Observation (P&O) method is widely used due to its easy implementation and simplicity. The P&O usually requires a dithering scheme to reduce noise effects, but the dithering scheme slows the tracking response time. Tracking speed is the most important factor for improving efficiency under frequent environmental change. The proposed method is based on the Kalman filter. An adaptive MPPT algorithm which uses an instantaneous power slope has introduced, but process and sensor noises disturb its estimations. Thus, applying the Kalman filter to the adaptive algorithm is able to reduce tracking failures by the noises. It also keeps fast tracking performance of the adaptive algorithm, so that enables using the Kalman filter to generate more powers under rapid weather changes than using the P&O. For simulations, a PV system is introduced with a 30kW array and MPPT controller designs using the Kalman filter and P&O. Simulation results are provided the comparison of the proposed method and the P&O on transient response for sudden system restart and irradiation changes in different noise levels. The simulations are also performed using real irradiance data for two entire days, one day is smooth irradiance changes and the other day is severe irradiance changes. The proposed method has showed the better performance when the irradiance is severely fluctuating than the P&O while the two methods have showed the similar performances on the smooth irradiance changes. / Master of Science

In several areas around the world, clean water is a precious asset that at anytime, and mainly due to circumstances of weather and climate, can become scarce. Mainly in the dry and remote places, people suffer with lack of water. A solution for this suffering can be a water desalination system, which makes water potable and usable for industry. That solution inherently, brings the problem of power requirement, which is sometimes arduous to accomplish in such remote areas of difficult access and long distances to overcome to build the infrastructure required to operate an electric power plant. Texas and the USA also face this scenario for many regions, for which the government has been creating some programs and driving forward incentives, looking for solutions to support water desalination. Water desalination has future applications for municipalities water-consuming or for arid and remote regions, as well as for industries that rely on heavy water usage, such as natural gas drilling operations, for which millions of gallons are trucked overland to the site and also hauled away afterwards, when the waste water produced must be treated. This thesis created the concept of autonomy for water desalination plants replacing the actual power supply from fossil fuel to a renewable source from wind or sun, giving capacity to them to produce its own electricity to operate as an autonomous unit, as demonstrated in the business case done for the Brownsville water desalination facility.