Full Report





Welcome to the chargeBlue Full technical report. You can use the links on the left to navigate through particular sections of our report. Or, you can click on the link below to download the full report to navigate via your pdf reader. Thanks for showing interest in chargeBlue, and don't hesitate to contact any of us via email if you have any questions.




1.1 Cover Page
1.2 Abstract
1.3 Introduction
1.4 Background
1.5 Impact Statement
1.6 Technical Description
1.7 Time Line
1.8 Distribution of Effort
1.9 Deliverables
1.10 Future Work
1.11 References
1.12 Budget / Parts List
1.13 Acknowledgements
1.14 Biographical Sketches
1.15 Reflection
Appendix A
Appendix B



1.1 Cover Page



chargeBlue
Jordon Catron(jordan.catron@uky.edu)
Ryan Copple(ryan.copple@uky.edu))
Alexa Eggert(alexa.eggert@uky.edu)
Jordon Catron(jordan.catron@uky.edu)
Matthew Layson(malays2@uky.edu)
Jim Wang(default.mp3@uky.edu)
Christina Yeoman(christina.yeoman@uky.edu)
Faculty Advisor
Dr. Donald Colliver(dcolliver@uky.edu)
Class Advisor
Dr. Regina Hannemann(regina.hannemann@uky.edu)




2011-04-21


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1.2 Abstract



The chargeBlue project aims to create an easily expandable 2.3kW net metered photovoltaic array, with advanced data acquisition devices, that feeds into the power grid, while also outputting data about the array and the power generated via a graphical interface that could be accessed on the Internet. The creation of such an array would be a small start to offset the carbon footprint of the university directly, and the modularity of the design would allow the university to expand the array (and thus further reduce the carbon footprint) whenever funding allows. The graphical online interface would allow a highly visible and easy to comprehend flow of data to be viewed by the general public, which would help further the university’s goals of environmental sustainability. The interface would both help educate the public about solar energy, while also creating an easy way to compile raw data on the performance of the array itself. The advanced data acquisition system, coupled with the unusually articulate mounting ystem, would also allow the usage of the array itself as an educational tool for the university, giving raw, local data about the abilities of solar energy in the state of Kentucky, thus providing students with an opportunity to experiment with the various configurations of solar first-hand.


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1.3 Intoduction



The idea of using solar cells to create power is a fairly young field, although men such as Einstein, Hertz, and Fritts were generating ideas about this innovative means of obtaining power long before their time. In 1953, Dr. Dan Trivich of Wayne State University began making efficiency calculations based on the spectrum of the sun. And, in 1954, Bell Laboratories was formed, which produced a silicon solar cell with 4% efficiency. Throughout the next 20 years, there were more installations of solar cells, an increase in efficiency, and less dollar amount per watt. In 1973, the University of Delaware built "Solar One," one of the world’s first photovoltaic powered residences, which was a PV/thermal hybrid. Shortly thereafter, The U.S. Department of Energy launched the Solar Energy Institute laboratory created for harnessing power from the sun. Years later, in 2000, the International Space Station began installing solar panels on the largest solar array deployed into space.

With the rise in concern about the environmental impact of human-generated energy, there has been a shift in focus from traditional fossil fuel usage to renewable sources, including solar. Constant advances in the field of photovoltaics have driven costs down, to that point that consumers are now able to potentially harness the power of the sun in order to generate their own electricity.


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1.4 Background



The genesis of this project grew from the discussion between Dr. Colliver, one of the leading solar experts at the University of Kentucky, and Shane Tedder, who was the Sustainability Coordinator in the Office of Residence Life at the University of Kentucky. The University of Kentucky is one of the largest institutions within the state of Kentucky. While there have been several projects aimed at creating a more environmentally sound campus, such as the “S•KY BLUE” solar house, the “Gardenstop” green bus stop, the “Gato del Sol 4” solar car, etc., almost none of these, besides the new Davis Marksbury Building, have a direct impact on the day to day operations of the university. What makes this even more pressing is the issue that much of the power that drives the grid that the university is connected to is derived from coal, one of the most environmentally damaging sources of fuel. The discussion started with the idea of adding a charging station to the Solar House project for an electric car, such as the new Chevy Volt or Nissan LEAF. Further discussion led to the more practical idea of a solar charger for the Physical Plant Department’s golf carts.

In researching the aforementioned idea, the concept of net metering was explored.  Net metering is essentially a way of being credited for the energy one generates by tying an energy generating device into the power grid.  This concept allows for great flexibility in the location of the solar array because the energy can technically be used anywhere there is access to an electrical outlet. Therefore, the cart charging concept was scrapped, and replaced with a small array that was tied directly to the grid to allow net metering. The array would also be equipped with monitoring systems, which would thus allow acquisition of the raw electric generation data, which in turn could be used as a hands-on educational tool for the University.

A website was also mandated, as a way to provide further visibility about solar energy, and to create an educational component that would accessible to the general public. Some of the more basic generation data would also be displayed on the website, to give a real-world example of solar in action. Thus, the website would serve both as an education tool and as a means to advocate renewable energy, solar in particular.

Thus, overall, the project was not conceived to save the University of Kentucky money on electricity, but as an educational tool, a proof of concept, and as a way to advocate the usage of renewables.

In the long run, the goal of the project, as stated in the final few paragraphs above, did not change. The second semester was spent finalizing the panel selection, and ultimately ordering the panels through Dr. Colliver. This was also done in conjunction with ordering the microinverters. During the time the orders were going through, the mounting was the team’s main concern. With the majority of the design going through Jordan and Dr. Colliver the design was altered numerous times, ultimately coming up with what is seen below. The University was taking care of the mounting hardware, with the team purchasing the supplies. This was done during the first few weeks of April, leaving the last few weeks of April for work on connecting the website to the array for real time data.


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1.5 Impact Statement



With the growing concern about the environmental impact of extensive fossil fuel usage, renewable energy sources have grown rapidly in importance. Once a merely a niche item relegated to powering calculators and space vehicles, photovoltaics have grown rapidly to become a potentially viable source of energy generation for the electric grid. Therefore, the creation of this small array would serve to help the University of Kentucky advocate the usage of renewable energy, while simultaneously cutting down on the usage of electricity generated by coal. It would also give the University a power educational tool, as it the design of the array allows for variations in some of the most important parameters in photovoltaic collector mounting. It also provides a proof-of-concept to the University for building arrays relying on the relatively new microinverter technology.

1.5.1 Financial Impact
1.5.2 Manufacturability
1.5.3 Social Impact
1.5.4 Environmental Impact
1.5.5 Relevant Standards





1.5.1 Financial Impact

With the current cost of photovoltaic technology, the array is not competitive from a purely budgetary point of view, particularly in Kentucky, considering the low cost of coal and its overwhelming usage on the Kentucky gird, providing over 90% of the power generated [1]. However, there are a myriad of outside factors that could easily make a solar array far more competitive for the average consumer looking to install solar on their home or business. These include numerous state and Federal tax incentives, rebates offered by utilities, reselling of the electricity generated, etc.

One of the standard ways of determining the financial feasibility of a project is to calculate its net present worth, which the difference between the present worth of benefits and the present worth of cost [2].
  • Overall budget of 11000 USD for a 2.3 kilowatt array
    • 7000 USD on panels
    • 2000 USD on inverters
    • 2000 USD on mounting
  • 30% of price of installation Federal tax credit [8]
    • This tax credit was established by the Energy Policy Act of 2005, and allows a taxpayer to claim a credit of 30% of qualified expenditures, such as labor costs for on-site preparation, assembly or original system installation, wiring costs, etc. For any system assembled after 2008, there is no limit on the amount of the credit. This incentive expires in 2017. Interestingly, this system does not have to be installed on a home that is the taxpayer’s principal residence.
  • 500 USD Kentucky state tax credit [9]
    • This tax credit offers a taxpayer to claim 3 USD per watt of DC power generated; however, it is capped 500 USD, and since
      3 USD⁄Watt x 2300 = 6900 USD
      such a system would only receive the 500 USD. This system must be installed at the taxpayer’s principal residence.
  • An inflation rate of 3.0%
    • This was taken from general knowledge, as 3.0% inflation is an oft-quoted number. Calculations of the actual inflation from 2001 to 2010 using the Consumer Price Index for urban consumers as calculated by the Bureau of Labor and Statistics show the inflation rate varying from -0.356% to 4.239%, with most annual rates between 2.5% to 3.5% [3]. One can calculate the rough inflation from year to year by the following formula:
      inflation = (CPIlater year-CPIearlier year)⁄CPIearlier year x 100
  • Kentucky residential electricity rate of 0.0852 USD per kilowatt-hour [4]
    • This is actually somewhat of a worse-case scenario for solar, as Kentucky has historically had some of the lowest electricity prices in the United States. It would be very easy for the price of electricity in Kentucky to rise significantly, if carbon taxes are passed. Another factor that could drive up price significantly is that many of the baseload coal plants in Kentucky are approaching the end of their project lifespans; building new baseload plants would be a very capital-intensive project, and it would be quite possible for utilities to raise their prices to help fund these new plants.
  • Solar Renewable Energy Credit (SREC), which represent 1 megawatt-hour of electricity produced, sells for 225 USD each [5]
    • SREC Prices (USD)FebruaryMarchApril
      Delaware 2011226100
      Maryland In-State 2010320
      Maryland In-State 2011275276
      Massachusetts 2010515570
      New Jersey 2010640640620.5
      New Jersey 2011640640640
      Ohio In-State 2010399400
      Ohio Out-of-State 2010250210
      Ohio Out-of-State 2011225
      Pennsylvania 2010200176
      Pennsylvania 2011200181100
      Washington, D.C. 2010199.99


      Of course, as more and more states attempt to fulfill their renewable energy mandates, there could potentially be more demand for SRECs, which could easily drive prices up while stabilizing the market.
  • 20 year length of analysis
    • A 20 year length of analysis was chosen as this is almost the universal length of the warranty on photovoltaic panels. Inverters, on the other hand, tend to have a warranty of 10 years. Anecdotally, there have been reports that quality panels can operate with acceptable efficiencies well past 20 years.
  • Array generates 2950 kilowatt-hours per year
    • This number was generated by PVSyst for a system utilizing Kyocera KD230GX-LFB panels, set at a 38° angle facing true south, for environmental data for Lexington, Kentucky. This would actually be considered a bit of a worse-case scenario, considering Kentucky’s unsuitability for solar, particularly when compared to the American Southwest.


The sale of SRECs would generate this much income:
225 USD⁄1 MWh X 1 MWh⁄1000 kWh X 2950 KWh⁄1 year = 663.75 USD per year

Net-metering would generate this much income:
0.0852 USD⁄kWh X 2950 MWh⁄1 year = 251.34 USD

Thus, the net present benefit of the system can be calculated using the uniform series present worth equation [6]:
P = A[(1+i)n-1⁄i(1+i)n ]

Where A is the set yearly income, i is the interest rate, n is the number of time unites that analysis will cover, and P is the net present worth. Therefore, the system would be creating this much benefit:
(663.75+251.34) X [(1+0.03)20-1⁄0.03(1+0.03)20] = 13614.23 USD

The cost of the array, after the discounts, on the other hand, would be:
11000 x 0.7 - 500 = 7200 USD

Thus, the system has a net present worth of:
13614.23 - 7200 = 6414.23 USD

One could also view this has having the following benefit-cost ration [7]:
benefit⁄cost = 13614.23⁄7200 ≈ 1.89

A non-negative net present worth and a benefit-cost ratio exceeding 1.0 both suggest that this would be a sound investment to make from a purely financial point of view. This analysis assumes that there is no need to replace any parts over the lifetime of the system; on the flip side, it also ignores any possible salvage value the system would have at the end of the analysis. It also excludes operating and maintenance (O&M) costs, as such expenditures should be minimal, as the only real regular maintenance that must be done is the cleaning of the panels.

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1.5.2 Manufacturability


Manufacturability is defined as the extent to which a good can be manufactured with relative ease at minimum cost and maximum reliability [10].  With this concept in mind, the mounting for the solar array was designed to be broken up into several different sections.  Rather than having one large foundation fabricated that would span a width of over thirty feet, three separate foundations were made up and then pieced together with various nuts, bolts and steel plates.   The rest of the racking system consists of several individual components as well.  These pieces are light enough that the entire structure can be assembled and secured on site.  This prevents the average fabricator or installer from having issues with moving the components from one place to the other.

The mounting was also designed to make the possibility of future expansion rather simplistic.   All of the components needed to mount one additional panel can be fabricated as designed with the exception of reducing the width of the main base beam to a width which accommodates one panel only.   This allows the array to be expanded up to the full width of the deck in the future if so desired.
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1.5.3 Social Impact


This social initiative brings the project at the fingertips of curious individuals who are seeking to understand why and how the project developed. With the help of about and design pages, the website can portray more accurately the purpose of the project. A gallery of photos taken throughout the duration of the project allows viewers to feel they have been with us from the beginning, giving them a step by step instruction kit to design their own panel system. The social website also reflects real-time data from the panels and displays it in an easy to read format that illustrates critical information such as instantaneous power, power over time, and per panel output.

Another social aspect of the chargeBlue project is the Facebook page that represents the team’s mission. On most of the major pages of the website, Facebook plug-ins link the chargeBlue website to its Facebook page that allows viewers to “like” the project and help promote the projects existence and goals. The Facebook page is a great way to promote the name and mission of the project to a large amount of people quickly, giving each person a taste for the purpose of chargeBlue.
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1.5.4 Environmental Impact


While popular knowledge has deemed the various renewable energy generation technologies to be zero-emissions, even cursory analysis of the environmental impact of anthropogenic means of energy production will show that this is not the case. Photovoltaic solar energy is, of course, no different.

While it is quite true that one could state that there are no emissions from the operation of photovoltaic devices, this is quite a different statement than one stating that there are no emissions created all from the usage of photovoltaic devices. The main considerations in an analysis on the environmental impact of photovoltaics are heavy metal discharge (primarily during operations and at end-of-life disposal) and the energy used for the manufacturing of PV.

For the most part, the greatest concern for PV in terms of heavy metal discharge is the emission of cadmium, as it is a key component in thin-film cadmium telluride (CdTe) PV technology. This in turn can be divided into two distinct ways of discharge: direct, which involves the release of cadmium directly from the manufacturing of CdTe PV, and indirect, which is the amount of Cd that would be released due to the generation of electricity used to manufacture the CdTe PV, which would be applicable to all PV technologies. For CdTe PV modules with a 30 year lifespan, 9% efficiency, and an average production of 1800 kWh per m^2 per year, such a module would probably generate about 0.02 grams of Cd per GWh of capacity; this would include emission of Cd from mining, smelting, purification, and synthesis to CdTe, along with possible accidental release due to structural failure of a CdTe panel [11]. Compare that to the estimated 2 to 7 grams of Cd per GWh of capacity for a coal plant [12]. As this project is does not utilize thin-film CdTe, the Cd emissions would probably be even less.

Most other heavy metals that might be discharged would be for indirect discharge, and would be heavily dependent on the energy source used to manufacture the PV panels. The only real possible constant between panels would be the possibility of lead (Pb) emissions, as this is a common additive in glass; however, most solar glass often uses much less Pb than most construction-grade glass [13], so this may be a moot concern.

By far, the greatest environmental impact of using PV technology is the large amount of energy used in order to manufacture the panels. The creation of ultrapure silicon is a very energy intensive process, with almost half of the energy consumed used to produce a PV module being devoted to making the Si feedstock, while another fourth is dedicated to creating the Si ingots and transforming that into a wafer [14]. The actual production of the cell, the module assembly, and the creation of the frame takes up the final fourth; the frame is actually a relatively significant source of energy consumption, as aluminum smelting is a relatively energy intensive progress.

Thus, it would take approximately 4000 megajoules of energy in order to create 1 square meter of polycrystalline silicon PV [14], which equates to 1111 kWh of energy. Thus, for the array that chargeBlue is building, the following energy pay-back time was calculated:
1111 kWh⁄m2 x area of panels x number of panels ⁄ annual output of array = 1111 kWh⁄m2 x 1.6m2x10 ⁄ 2950 kWh⁄year ≈ 6 years

Also directly tied to the electricity used during the manufacturing of the PV panels the question of greenhouse gas emissions from the power generation used during manufacturing. PV has far less greenhouse gas emissions in a cradle to grave analysis than coal and natural gas generation, but is general higher than wind and nuclear [15]. Of course, this is highly dependent on the generation source for the manufacturer of the PV panels. The Kyocera KD230GX was manufactured in California, which relies heavily on natural gas (60% of the electricity generated), along with some hydroelectric, nuclear, and various renewable energy technologies (wind and geothermal) [16]. Natural gas used in combined cycle gas turbines releases approximately 400 grams of CO2 per kWh of electricity generated, nuclear approximately 8, and wind approximately 11 [14]; assuming that natural gas was the sole supplier to energy to the production of the solar panels used, the following amount of CO2 emissions was calculated:
1111 kWh⁄m2 x area of panels x number of panels x 400 grams of CO2⁄kWh
≈ 7.8 short tons of CO2

Of course, such a number represents a worse-case scenario for manufacturing in California. Assuming a 20 year lifespan of the system, and the previously calculated annual output of the array, the system would be essentially putting out this much CO2 emissions:
7110.4 kg of CO2⁄20 years x 2950 kWh⁄year = 0.205 kg of CO2 per kWh = 120.5 grams of CO2 per kWh

One should note that this number is actually substantially higher than what was calculated by some studies, which show the number to be as low as 35 grams of CO2 per kWh, albeit if the panels were manufactured in Europe [14]. Compared to the estimated 1000 grams of CO2 per kWh for coal [14], which is Kentucky’s primary energy source, and one can see that solar, while not without emissions, is substantially better than coal, or even natural gas.

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1.5.5 Relevant Standards

Every project in senior design is supposed to teach the student and the groups some things about real life. In life you do not have an assignment with clear-cut instructions and there are going to be worldly things that everyone has to think about in regards to themselves, others, the company, and the impact it has. We are given a taste of this with our senior design projects. In our project especially, there are a lot of standards we have to follow, and these are outlined – although not so simply – in the National Electrical Code. With an electrical project such as ours it is vital that anyone who comes into contact with the device is safe, as well as the surrounding area. There is a whole section in the National Electrical Code that is specific to the use of Photovoltaic Systems. This section is under Article 690 and is fourteen pages long. Each section of the code in 690 talks about different aspects of the array and how it will be wired, grounded, amongst other things. Section IV states all of the regulations that must be followed regarding the details of the wires. It states that the wires must be reachable so that they can be replaced if need be. Because of this, the wires must also be flexible so that the array can be moved and the angles can be changed. This article in itself has been a major factor in our design for the mounting hardware because the panels need to be able to move freely and still be connected to each micro inverter and ultimately the EOS box.  Not only are these wires of concern but also those that will ground the whole array in case of overload. Each of these aspects is very important, especially at the stage of our project that we are in, mounting and assembly.

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Technical Descriptions


1.6.1 Electrical Systems 1.6.2 Mechanical Systems


1.6.1 Electrical Systems

    1.6.1.1 Basic Description

     The diagram on the preceding page describes the basic electrical layout of the system. The collectors chosen are ten Kyocera KD230GX-LFB 230 Watt panels. They are of a polycrystalline silicon composition [17]. Each panel’s DC output feeds into an Enphase M190 inverter as shown in Figure 1.

    Enphase Energy M190 Micro-Inverter (Figure 1)


    The inverters are daisy-chained together with the final output connected to “Inverter 1.” At this final output, a breakout cable is used. Four wires are used in the 208V three phase setup: L1, L2, L3, and Neutral. The line to line voltage is approximately 208V and the line to neutral voltage is approximately 120V.

    L1, L2, and L3 are then fed through an AC Disconnect switch and into the building’s power panel. This circuit will be protected by a 15A, 3-pole breaker. The neutral line is directly connected. Data from the Enphase micro-inverters is carried on the neutral line. The Enphase Envoy unit shown in Figure 2, connected to a 120V outlet, polls the micro-inverters for output data. This unit is connected to the internet via an Ethernet cable. The Envoy uploads data to Enphase’s servers to be monitored remotely from the internet.


    Enphase Envoy Communications Gateway (Figure 2)


    Notice the accommodation in the schematic for the EOS data acquisition system. Each panel’s output is routed through the measurement system. Although it will be discussed in more detail later, a figure is given to explain the path of the wires.

    Micro-inverters were chosen for many reasons. They include: an easily scalable system, better efficiency, and partial shading performance.

    A traditional centrally inverted system involves PV panels placed in series. Each string may be connected in parallel to another string or directly to the inverter input. The quantity of panels on each string is determined by the inverter’s voltage range on its inputs. Any reduction or addition of panels results in having to redesign the number of panels on each string and re-configuring any strings in parallel with that string. If the voltage range is not optimal with the changed configuration, a new inverter may need to be selected.

    Better efficiency is also achieved since each panel’s maximum power point (MPPT) is adjusted individually.  The manufacturer estimates a 5-25% increase in energy harvest [18].  Performance in the event of shading due to shadows or debris is also enhanced. When panels are connected in series, the diodes in each panel are configured such that all panels produce at the lowest voltage in the string. This can decimate the output efficiency.  If one panel of ten in our system (10% of the array) is completely obscured, the array will lose only 10% of its output. This is in great contrast to the 50% loss in output in a central inverter setup [19].

    Unfortunately, there is a drawback: there is only one company actually producing micro-inverters at this time. Enphase Energy has a de facto monopoly on its efficient form of data acquisition from its inverters. Thus, all information access requires a yearly subscription. Only extremely limited data is available without this subscription. Even with the subscription, the energy production data cannot be exported in any form. The company’s Acceptable Use Policy specifically prohibits any attempt to “...access any Website or any web page thereof by any means other than the interface that is provided by Enphase Energy… [20].” This led us to seek a secondary monitoring system, which will be discussed next.

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    1.6.1.2 EOS Monitoring System


     Rationale for Implementation
    The chargeBlue team decided to install the EOS monitoring system which will track and report critical data in real-time. This data will be displayed on the chargeBlue website for public viewing and stored on a local server for in depth analysis. The EOS system can determine if a single panel is under performing relative to other panels and alert the system manager of possible panel failure.

    How the EOS Integrates into the Existing System
    The EOS system consists of data acquisition modules that are connected between the solar panels and the per panel inverters. These modules have DC shunts which measure voltage and current directly from the panels. A web server communications box will gather the voltage and current readings from the data acquisition modules and calculate the instantaneous power produced. The calculation will be stored in the communication box for future reference and pushed to the public website. At any time, the system manager can review the data stored on the server. Data can be displayed by minute, hour, day, month, and year. Graphs can show power produce by each panel and compared over time.

    The Web Server
    The web server is a crucial part of the EOS system. This devices communicates directly with the data acquisition units which are connected to each panel and allows system mangers to access the information via the Internet.


    The Web Server (Figure 3)


    Coms (2,3,4): Connections to the EOS VMU-M units for collecting data per panel.
    LAN Port: Internet. Allows system manager to view data in real-time. Also for initial configuration.
    VGA: Allows system managers to connect a monitor for real-time display.
    Power Supply: 120V power connection for the web server.

    EOS Graphs
    The EOS web server can display the amount of power each panel generates onto one graph for easy comparison. This allows system managers to identity if one panel is not producing the correct amount of power relative to other panels.


    EOS Graphs (Figure 4)


    EOS Enclosure
    The EOS system needs to be enclosed in a structure that is weather resistant but allows for the connections of each panel, AC power, Ethernet communication, and Irradiance sensor. The NEMA 3R enclosures from Automation Direct is a good choice for this EOS system.


    EOS Enclosure (Figure 5)


    The Enclosure box will also need two, ten terminal strips for connecting each of the panels to the EOS system. Like wise din railing will be needed for mounting the VMUs to the enclosure box.

    EOS Box Diagram The box diagram shows a high level connection between panels, VMU’s, terminals, and the network.


    EOS Box Diagram (Figure 6)


    EOS Line Schematic
    The line schematic gives a specific view where each lines connects in the box.


    EOS Line Schematic (Figure 7)


    EOS Financial Impact on the Project
    The EOS systems is a rather costly commercial grade data acquisition solution. For the average homeowner, such a system would most likely be seen as overkill; therefore, the general net present value calculations would not include this in the overall cost. The EOS system is being utilized under the consideration that the array being built is being used primarily as an educational, secondarily as an advocacy tool, and maximization of renewable energy created as a tertiary goal.

    EOS Wire Sizing
    The addition of the EOS system adds 20 current-carrying conductors: one from each panel and another returning to each respective inverter. To keep costs manageable, we must not employ USE-2 wire implemented in both the panel leads and inverter leads in the run to the EOS Array panel. Thus, each conductor will be connected to a THHW specification wire for the “long run.” This wire is not certified for UV exposure, so it will be run inside Electrical Metallic Tubing (EMT). At points in the conduit, there may be as many as 20 wires. In order to determine the wire gauge needed, several calculations were performed.

    Determining Wire Current
    First, we must determine the actual current travelling through each wire. Using Article 690.8(A)(1), we may consider the current in each wire to be 125% of the rated short circuit current of the photovoltaic module [21]. From the datasheet of the Kyocera KD-230GX-LFB, the short circuit is 8.36A. Thus, we will consider the current in each conductor to be 8.36A x 1.25 = 10.45A

    Adjusting for Wire Bundling
    Table 310.16 of the National Electrical Code describes the allowable ampacities of insulated conductors in bundles of 3 or less in temperatures of 60 degrees through 90º C [22]. Given our 20 wire bundle, we need an adjustment factor. This is given in Table 310.15(B)(2)(a).  For 10-20 current carrying conductors, the ampacity for a given wire type must be reduced by 50%. [23]

    Adjusting for Temperature
    Wire ampacity is given in Table 310.16 for THHW wire rated to 90º C.  Each gauge’s ampacity must be adjusted for ambient temperature. The correction factors are also listed in Table 310.16. A suggested maximum ambient temperature for Lexington, KY may be found in the 2009 ASHRAE Handbook – Fundamentals [25]. The maximum average dry-bulb temperature was found to be 33.8º C. We must now compensate for temperature rise in conduit exposed to direct sunlight on a rooftop. For conduit less than ½ inch above the roof’s surface, Table 310.15(B)(2)(c) says that 33 degrees C must be added to the ambient temperature.[24] Thus, the ambient temperature used to choose the ampacity correction factor will be 33.8 + 33 = 66.8ºC.

    Final Calculation
    For 20 bundled THHW conductors rated at 90º C, we will choose 10 AWG wire. The calculation is shown below.
    For 10 AWG THHW 90º C wire, the given ampacity is 40A. Bundling 20 wires together leads to a reduction of 50% 40A x 0.5 = 20A
    The adjusted ambient temperature is 66.8º C, which corresponds to a correction factor of 0.58. 20A x 0.58A = 11.6A. Given the maximum current of 10.45A, 10 AWG THHW 90 wire will suit this application.

    Conduit Sizing
    Since a wire gauge has been chosen, we may now determine the conduit size required to carry twenty 10 AWG THHW wires. Table C.1 shows the maximum number of conductors in electrical metallic tubing (EMT). Up to twenty-four 10 AWG THHW conductors may be carried in 1½ inch conduit [26].  

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    1.6.1.3 Performance Simulation
    PVSyst is an industry-standard whole-system simulation program. It can be configured for in-depth (extremely complex) performance simulations or somewhat more basic ones [27]. In the course of our project, it was used to simulate various panels with a micro-inverter configuration.

    A typical panel was simulated in a 2.3kW array aimed due South and titled at 38 degrees. Yearly power output was calculated using NREL’s 30-year weather data for Lexington in combination with panel and inverter efficiencies [28].

    Five 230W panels were initially selected from companies with proven industry records. They were:

    Schott POLY 230 - Poly Si
    SolarWorld Sunmodule Plus SW230 - Mono Si
    Kyocera KD230GX-LPB - Poly Si
    Sharp ND-U230C1 - Poly Si
    Sharp NU-U230F3 - Mono Si


    Each was simulated in PVSyst under the given test parameters. This was simple, as the PVSyst database contained current data for each panel. For one year, the power output for each 2.3kW array was:

    Kyocera KD230GX-LPB - 2954 kWh
    Schott POLY 230 -  2943 kWh
    SolarWorld Sunmodule Plus SW230 - 2931 kWh
    Sharp NU-U230F3 - 2877 kWh
    Sharp ND-U230C1 - 2846 kWh


    The Kyocera KD230GX-LPB was a clear winner, as it was the best performer and the cheapest panel in the group.

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    1.6.1.4 Design Changes
    Originally, our advisor had believed the electrical tie-in to the building needed to be 208V single phase. Much work was put into configuring the Enphase micro-inverters into this configuration and finalizing that design. Later, we were told the building needed a 3-phase tie-in.

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1.6.2 Mechanical Systems

    1.6.2.1 Site Selection Process
    There are a number of factors that were taken into consideration when searching for the ideal location for the chargeBlue solar array.  The site would need to exhibit most, if not all, of the following characteristics: a flat surface or roof with a south-facing slant, minimal shading, minimal susceptibility to theft/vandalism, area for future expansion, and easy accessibility for team members and maintenance personnel.

    The initial array location was the roof of the Peterson Building found between South Upper Street and South Limestone Street.  This location, however, was eventually deemed unsuitable due to factors such as an inapt geographical orientation and several nearby sources of shading and harmful debris.  As a result, the team proceeded to visit various regions throughout UK’s campus in search of an ideal location.  Other proposed sites included the bus stop in the Blue Lot outside of Commonwealth Stadium as well as the roof of Nutter Field House.  The bus stop was eventually nullified due to surrounding landscape which would cause a great deal of shading.    It was also a relatively low altitude location which would have left the array susceptible to theft and/or vandalism.  The roof of Nutter Field House was found to have a roof which slanted in the eastern and western directions.  An ideal roof location would either be flat or have a portion which slanted to the South, allowing for maximum average sun exposure throughout the day.

    After nearly a month of searching, the roof of the Barnhart Building was proposed as a potential location.  The team congregated with their advisor and decided that the location possessed each of the five core characteristics that the team desired in a location.  Hence, the Barnhart building became the new home for the chargeBlue solar array.

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    1.6.2.2 Site Survey
    The roof of the Barnhart Building is home to the solar lab.  This space is owned by the advisor of the chargeBlue team.  The exact coordinates of the array are 38.03° N Latitude, 84.51° W Longitude [30].  The blue rectangle seen below in Figure 8 shows the exact position of the array.


    Charles E. Barnhart Building (Figure 8)


    The angular position of the sun or specific location from true North in a clockwise direction is known as the azimuth angle. The ideal angle for a fixed array in the northern hemisphere is 180°, or true South.  The azimuth angle of the chosen location for the array is 199.8° [32], deviating 19.8° West from the South.  However, studies have shown that a collector can deviate as much as 22.5° from South with less than a 2% reduction in annual collection at latitudes of up to 45° [31].  Given the latitude of this location, the array is positioned for excellent solar radiation exposure.

    A collector’s tilt angle also plays an important role in how much radiation can be absorbed.   For a fixed array in the northern hemisphere, the site selected should allow for collectors to be tilted upward at roughly the degree of latitude of their geographic location.  Due to varying solar altitudes of the sun throughout the different seasons, it is ideal to allow for tilt angles to vary at least +/- 15°.  The chargeBlue array has been designed to allow a 38° (latitude) tilt angle as well as the +/-15° to compensate for the seasons.  

    An on-site view of the location can be seen in Figure 9 and 10 below.


    (Figure 9)



    (Figure 10)


    The array was designed to become an extension of the deck seen in the figure.  Due to the gravel/tar makeup of the roof, several location design specifications were implemented in order to keep human and equipment contact with the roof at a minimum.  These location-specific specs are as follows:

    • Mounting shall be self-sustainable from the deck only.
    • All panels shall be adjustable from the deck
    • No persons/maintenance personnel shall be required to step foot onto the roof other than during initial installation
    • All wiring, conduit, etc. shall run along the deck edge and/or mounting


    These specs added greatly to the degree of complexity of the racking system.  Keeping these specifications in mind, numerous dimensions were taken with a measuring tape and used as guidelines in the mounting design process.

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    1.6.2.3 Racking System Design
    Other specifications were involved in addition to the location-specifics mentioned above.   These were as follows:

    • Each panel shall tilt independently from one another
    • Each panel can be adjusted to a tilt angle between 0° and 90°
    • The entire system must withstand all possible static and dynamic loads


    After multiple revisions of the initial design concept, a general consensus was reached by the team and a computer-aided-design program was used to construct a scale model of the racking.   A picture of the fully assembled racking system can be seen below in Figure 11. Each individual component involved in the design can be seen in Appendix A.  


    Racking System (Figure 11)


    The entire system is fabricated with various forms of modified square and rectangular steel tubing. Due to the high price of galvanization, each component has been painted in order to protect it from rusting due to rain, snow, frost, etc.       

    The foundation of the racking is composed of three pieces of 4”x2”x1/4” rectangular square tubing.   The left, center and right pieces are cut to lengths of 12’, 12’4”, and 12’2”, respectively for a total width of 36’ 6”.  These pieces connect to the pillar supports underneath the deck with ¾” bolts.  All other components of the system rely on these members as a foundation.       

    Each horizontal slider section is composed of a 4”x2”x1/4” rectangular square tube at a length of 6’.  Four slider guides have been welded to each of these.  See the slider section of Appendix A.   for a visual representation.  These guides are 1/4” thick and have been cut to lengths and widths of 5’6”x3/4”.  These provide a track for the C bracket to slide back and forth on with ease.  A steel plate has been welded to the end of the slider which connects to a mating plate on the other side of the base beam with 3/8” bolts.  Each plate is 6” square and has a thickness of 3/8”.       

    Each horizontal slider also has a 2” square upright welded to it.  These are each 5’1.5” in length and have a wall thickness of 1/8”.  These provide the vertical slide guide and support for the panel rack.       

    The panel racks are fabricated with 1.25”x1.25”x1/8” square steel tubing.  These are welded together to make a rectangle with a length and width of 5’5.5”x3’4”.  Each solar panel is attached to its own panel rack.       

    Each panel rack is secured to the upright via an L bracket and mate.  The brackets are made from 3/16” steel.  The brackets are placed around the upright and secured in position with 5/16” bolts.  The panel rack is also attached to this bracket with bolts of the same diameter.       

    The C brackets connect the bottom of the panel rack to the horizontal slider.  These are composed of ¼” thick steel.  They are connected to the rack via 5/16” stainless steel bolts and are free to slide up and down the horizontal when the upright brackets are not secured.

    The racking system has been designed to withstand both the static and dynamic loads that will be encountered.  The static load comprising of the system itself and the weight of the panels is approximately 1633.84 lbs.  The system has also been designed to withstand the designated wind speed of 90 mph and snow load for Fayette County of 15 lbs/ft2 as set by the Kentucky Building Code [29].  

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1.7 Time Line



Time FrameTask to Complete
Late OctoberPitch final proposal to sustainability, Meeting date TBD by Sustainability
November 1120 Minute Video: Design Review
Mid-NovemberDeliver Final Price List
Late-NovemberPresent Prototype Web Interface
December 7Executive Summary
December 10Prototype Construction Blueprint

Fall Semester Time Line (Table 1)

Time FrameTask to Complete
Late JanuaryDecision to use Microinverters
Early FebruaryPanel Selection Complete
Late March/Early AprilHardware and Mounting Design Complete
Late AprilInstall panels, connect to EOS Box, finish website
21 AprilFinish Final Report
29 AprilSenior Design Day
Spring Semester Time Line (Table 2)


Delays
There were various delays that were encountered throughout the project, some more serious than others. The first delay to occur was the issue of location; without a location, there was a possibility of the project not moving forward at all. However, there was no easy way to find a place on campus that was relatively visible (for the public relations aspect of the project) that was also facing the correct direction to maximize irradiance. There were difficulties with potential paperwork and administration politics that made various areas unsuitable, and in the end, a less visible location was chosen in order to minimize the amount of paperwork and possible delays.

The first substantial delay from a system design point of view was created from the fact that there was much controversy about the first choice of solar panels, the Yingli YL23P-29bs. While they were superb performance on aper, with an unmatched price point, Dr. Colliver expressed reservations about using panels from a relatively unknown company. While Yingli was one of the fastest growing PV panel manufacturers, they had not been in the market long enough to make an accurate assessment about the quality of their panels, nor of their ability to fulfill their warranty claims. Thus, an exhaustive panel analysis was undertaken, and eventually a much more established manufacturer was selected: Kyocera’s KD230GX-LFB.

The next serious issue faced was that of the inverter selection. While the original plans called for a standard central inverter solution, research and Dr. Colliver’s suggestions lead the team to look at a relatively unorthodox solution: microinverters. While the benefits of the microinverter system are numerous, there were also several drawbacks, the main two being lack of output options and proprietary monitoring systems. The lack of output options meant that there was difficulty determining what model to utilize, as there was no designated model for 208W single phase, as it was believed was the system on the roof of the Barnhart building. Thus, there was much consultation with Enphase, currently the only manufacturer of microinverters, about the suitability of the system. At the same time, the proprietary data acquisition system meant that there could be no local data acquisition system possible; in, all data had to come from Enphase, who provided rather limited data to begin with. Most third-party data acquisition units were designed to work for central inverter systems, and could not be easily adapted to the microinverter system. As the data acquisition was a key component of the project, and the electrical output problem was also running into issues to solve, there was serious consideration of going back to the central inverter system. However, in the end, it was discovered that the roof was actually 230W three phase, and that the funds for a more expensive data acquisition system had been secured, so the Enphase M190 was selected in the end.

The mounting system has long been delayed over and over again, due to the fact that it was a mechanical structure being designed by an electrical engineer. Many of the delays could be attributed to the simple fact that the team had no prior experience at all in mechanical engineering, and thus had to learn on the fly as to what was acceptable and what was not. This issue was compounded by the fact that there were unique specifications being called for on the mounting system, such as the ability to give the panels a full 90° of rotation. However, the team was able to slowly, but surely, fulfill the requirements for the mounting system, while also keeping it robust and relatively economical.

The website suffered similarly, with consistent delays, linked mainly to the fact that there was trouble finding an adequate data acquisition system. While Enphase offered a turnkey solution for the average user wishing to display the basic information about their array, this was not an option for the team, as specific and detailed data not reliant on a third-party was desired. With that requirement, it proved difficult to build a website, when one of the key components was missing. Eventually, a website was constructed, set up so that that once a data acquisition system was in place, it would be relatively easy to display and graph in the information captured.


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1.8 Distribution of Effort



Alexa Eggert: At the beginning of the project, Alexa was supposed to be in charge of the National Electrical Code and figuring out everything there was to know about net metering. As time progressed, she volunteered to take on responsibilities; she helped out with the website and writing content for it as well as taking on the social networking aspects, which was asked of us during the fall senior design day. Looking back on the whole project, she kept up with the responsibilities listed above, as well as adding the responsibility of being the team lead. Most of the semester was spent keeping everyone in line and on task. As the project progressed more papers were due and more things were expected out of the group as a whole. Trying to set a manageable time table that everyone can keep is difficult but with everyone’s help was achieved. She finished up reports and helped Christina and Ryan finish up the website.

Jordan Catron:  Jordan was in charge of the of design and construction of the racking system for the solar array.   Being an electrical engineer, this task proved to be quite challenging.  He was responsible for deciding what materials to use and making sure the system could withstand the various static and dynamic loads it would encounter. Once a design was solidified, he constructed a model using a computer-aided design system where every dimension was exactly to scale.  He then provided drawings of each individual component as well as a bill of materials to the manufacturer for fabrication.  

Ryan Copple: The initial design, construction, and some content curation of the chargeBlue website was tasked to Ryan. His work included the creation of the Home, About, Design, Gallery, Team, Location, and Sponsor pages. He also recoded the main CSS doc for better formatting on the website. Ryan also researched throughout the year different data acquisition systems which would be implemented into the solar project. The data collection system gathers information such as the real-time instantaneous power and displays the data in the form of graphs per panel.

Matt Layson: He designed the overall system. This included panel selection, system performance simulation, inverter selection, conductor sizing, vendor communication, in-depth research, schematic drafting and initial cost analysis. His cost analysis role was later shifted to a special emphasis on code compliance.

Jim Wang: Worked mostly with to help secure funding for the project. After funding was established, he moved onto economic and environmental analysis of the system.

Christina Yeoman: She started as working with Jordan on the mounting of the project, which both were able to come to a sound decision, with drafted models. Then, once the idea of having an educational interface was presented, Christina took over the reins of the website in that area. She has researched on various parts of the project when needed, and has been working to create the most sound website, which anyone can use to duplicate the teams project.


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1.9 Deliverables



The entire project was mapped out by a course syllabus that indicated when certain parts of the project would be due. During the Fall Semester many presentations were due to prove that work had been done on the project and that a clear understanding was there about what the project’s goal was. Along with these presentations a poster was due at the end of the semester with an update on where the project was after one semester’s work. The same applies to the second semester where one video was due indicating the situation the team was in, as well as some papers that could be used in future deliverables. Finally, at the end of the semester, at Senior Design Day, another poster will be due along with the final product of the project.

The final outcome will be a solar array on top of the Barnhart building that will send live data through the EOS system to the website: www.uky.edu/chargeblue. This website will allow for anyone to learn about solar power and how these arrays are implemented, as well as obtain up to minute data about our particular array.


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1.10 Future Work



Future expansion of the array is expected, in order to maximize usage of the Barnhart building’s rooftop. It is expected that the array would keep the same basic configuration, albeit with possible differences in panel selection. Eventually, the array may reach 8 to 10 kW generation capacity. Other than that, there is minimal future work that would be possible.


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1.11 References



[1] Energy Information Administration. (2011-04-04). Kentucky: Overview [Online]. Available: http://www.eia.gov/state/state-energy-profiles.cfm?sid=KY
[2] D. G. Newnan et al., “Present Worth Analysis” in Engineering Economic Analysis, 9th ed. New York: Oxford, 2004, ch. 5, sec. 3, pp. 151.
[3] Bureau of Labor Statistics. (2011-04-14). Databases & Tools: Top Picks [Online]. Available: http://data.bls.gov/cgi-bin/surveymost?bls
[4] Energy Information Administration. (2011-04-04). Kentucky: Overview [Online]. Available: http://www.eia.gov/state/state-energy-profiles.cfm?sid=KY
[5] SRECTrade. (2011-04-14). SREC Market Prices [Online]. Available: http://www.srectrade.com/srec_prices.php
[6] D. G. Newnan et al., “More Interest Formulas” in Engineering Economic Analysis, 9th ed. New York: Oxford, 2004, ch. 4, sec. 1, pp. 90.
[7] D. G. Newnan et al., “Economic Analysis in the Public Sector” in Engineering Economic Analysis, 9th ed. New York: Oxford, 2004, ch. 16, sec. 1, pp. 490.
[8] Database of State Incentives for Renewables and Efficiency. (2011-04-14). Residential Renewable Energy Tax Credit [Online]. Available: http://www.dsireusa.org/incentives/incentive.cfm?Incentive_Code=US37F&re=1&ee=1
[9] Database of State Incentives for Renewables and Efficiency. (2011-04-14). Renewable Energy Tax Credit (Personal) [Online]. Available: http://www.dsireusa.org/incentives/incentive.cfm?Incentive_Code=KY28F&re=1&ee=1
[10] "What is manufacturability? definition and meaning, Business Dictionary." BusinessDictionary.com - Online Business Dictionary. WebFinance, Inc, n.d. Web. 20 Apr. 2011. Available: http://www.businessdictionary.com/definition/manufacturability.html
[11] V. M. Fthenakis et al., "Emissions from Photovoltaic Life Cycles," Environmental Science & Technology, vol. 42, pp. 2168-2174, Jan. 2008.
[12] PISCES database for US power plants and US coal; Electric Power Research Institute: Palo Alto, CA, 2002.
[13] M. J. de Wild-Scholten, et al., “Implications of European Environmental Legislation for Photovoltaic Systems,” in 20th European Photovoltaic Solar Energy Conference, Barcelona, June 6–10, 2005.
[14] E. A. Alsema & M. J. de Wild-Scholten, “Environmental impacts of crystalline silicon photovoltaic module production,” in Materials Research Society Fall 2005 Meeting, Boston, MA, November, 2005.
[15] T. W. Zhang & D. A. Dornfield, “A Cradle to Grave Framework for Environmental Assessment of Photovoltaic Systems,” in 2010 IEEE International Symposium in Sustainable Systems and Technology, Arlington, VA, May 17–19, 2010
[16] U.S. Energy Information Administration, “Annual Electric Generator Report,” Department of Energy, Washington, D.C., March, 2010
[17] Kyocera, “Kyocera KD Module Specifications,” KD230GX-LFB datasheet, 2010.
[18] "Products Overview." Enphase Energy. Enphase Energy, 2010. Web. 30 Nov 2010. Available: http://www.enphaseenergy.com/products/index.cfm
[19] Muenster, Ralf. "Shade Happens." RenewableEnergyWorld.com  2 Feb. 2009. Web. 3 Dec 2010.   Available: http://www.renewableenergyworld.com/rea/news/article/2009/02/shade-happens-54551
[20] "Terms." Enphase Energy. Enphase Energy, 2011. Web. 18 Apr 2011. Available: http://www.enphaseenergy.com/acceptable_use
[21] “Article 690 – Solar Photovoltaic Systems” in National Electrical Code, 51st ed., Nat. Fire Protection Assoc., Quincy, MA, 2007, p.70-579.
[22] “Article 310 – Conductors for General Wiring” in National Electrical Code, 51st ed., Nat. Fire Protection Assoc., Quincy, MA, 2007, p.70-148.
[23] Ibid., 70-146.
[24] Ibid., 70-147.
[25] “Appendix: Design Conditions for Selected Locations” in 2009 ASHRAE Handbook – Fundamentals (SI Edition), Amer. Soc. of Heating, Refrigerating and Air-conditioning Engineers, Inc., Atlanta, GA, 2009, p. 14.22.
[26] “Annex C” in National Electrical Code, 51st ed., Nat. Fire Protection Assoc., Quincy, MA, 2007, p.70-704.
[27] "PVSyst: Software for Photovoltaic Systems." University of Geneva. University of Geneva, 2011. Web. 18 Apr 2011. Available: http://www.pvsyst.com
[28] “National Solar Radiation Database: TMY2 Files.” National Renewable Energy Laboratory: Renewable Research Data Center. NREL, 2011. Web. 18 Apr 2011. Available: http://rredc.nrel.gov/solar/old_data/nsrdb/tmy2/State.html
[29] Walden, Judith G.. The Kentucky building code  . 9th ed. Frankfort, Ky.: Dept. of Housing, Buildings, and Construction, 2007. Print.
[30] "Google Maps." Google Maps. N.p., n.d. Web. 18 Apr. 2011. Available: http://maps.google.com/maps?hl=en&tab=wl
[31] Messenger, Roger A., and Jerry Ventre. Photovoltaic systems engineering  . 3rd ed. Boca Raton, FL: CRC Press/Taylor & Francis, 2010. Print.
"Satellite Look Angles Satellite Heading Calculator ." Sadoun Satellite Sales. N.p., n.d. Web. 18 Apr. 2011. Available: http://www.sadoun.com/Sat/Installation/Satellite-Heading-Calculator.htm>


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1.12 Budget / Parts List



ItemCost per Unit (USD)UnitsTotal Cost (USD)
Kyocera KD230GX-LFB575105750
Enphase M190183101830
Enphase Envoy3421342
Enphase Envoy Subscription (5 years)1110110
Square D switch46146
EOS Array200012000
EOS Box700017000
Racking (Mounting Structure)2000N/A2000
Wiring & Conduit2000N/A2000
Total15328 USD


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1.13 Acknowledgements



chargeBlue would like to acknowledge and thank Student Sustainability Council and Student Government Association for their financial contributions as well as their cooperation in this project. We would also like to thank Dr. Donald Colliver for his time, guidance, and effort as our project advisor, and Dr. Regina Hannemann for her guidance as class advisor. We would also thank Dr. Ingrid St. Omer for her insights, and Mr. Shane Tedder for his support.


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1.14 Biographical Sketches



Alexa Eggert is a senior in Computer Engineering at the University of Kentucky. During the last four years she has taken an interest in wireless communications as well as the processes involved in MEMS. Upon graduation in May 2011 she will be commissioned as a 2nd Lieutenant in the United States Air Force where she will be a Developmental Engineer with an emphasis in computers.

Jordan Catron is majoring in Electrical Engineering at the University of Kentucky. He is currently employed at Lexmark International where he works as an Electrical Hardware Engineering Student. His main focus is on electronics with a current emphasis on sensor implementation.

Ryan Copple is a senior of Electrical Engineering at the University of Kentucky and is a previous employee of the UK Center for Visual and Virtual Environments. During his work at UK, Ryan developed skills relating to automation, computer interfacing, and micro-controls. Within the last year Ryan co-founded a local start-up company specializing in touchscreen way-finding technology.

Matt Layson is a senior in Electrical Engineering at the University of Kentucky. He has strong interest in RF engineering and renewable energy. He has worked as an intern for 2 years in military avionics, circuit protection, and product testing.

Jim Wang is majoring in Electrical Engineering at the University of Kentucky, and minoring in Mathematics, with a planned graduation date of 2011-05.

Christina Yeoman will graduate in May of 2011 with a degree in Computer Engineering as well as three minors in Computer Science, Spanish, and Mathematics. She has three and a half years of work experience as an intern for Lexmark International, Inc. While employed at Lexmark, she was also a member of Phi Sigma Rho and Delta Epsilon Iota. In the remaining year of her undergraduate career, she has been the Vice-Chair of IEEE at UK, as well as the starter of WECE (Women in Electrical and Computer Engineering). In the future, she plans on being a professor. Her interest area is in Power and Energy. She intends on receiving her Masters in that field of study.


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