Engineering Commons^™

Model-Based Analysis Of Electric Drive Options For Medium-Duty Parcel Delivery Vehicles, Robb A. Barnitt, Aaron D. Brooker, Laurie Ramroth

Publications (T)

Medium-duty vehicles are used in a broad array of fleet applications, including parcel delivery. These vehicles are excellent candidates for electric drive applications due to their transient-intensive duty cycles, operation in densely populated areas, and relatively high fuel consumption and emissions. The National Renewable Energy Laboratory (NREL) conducted a robust assessment of parcel delivery routes and completed a model-based techno-economic analysis of hybrid electric vehicle (HEV) and plug-in hybrid electric vehicle (PHEV) configurations. First, NREL characterized parcel delivery vehicle usage patterns, most notably daily distance driven and drive-cycle intensity. Second, drive-cycle analysis results framed the selection of drive cycles used …

College Of Engineering Senior Design Competition Fall 2010, University Of Nevada, Las Vegas

Fred and Harriet Cox Senior Design Competition Projects

Part of every UNLV engineering student’s academic experience, the senior design project stimulates engineering innovation and entrepreneurship. Each student in their senior year chooses, plans, designs, and prototypes a product in this required element of the curriculum. A capstone to the student’s educational career, the senior design project encourages the student to use everything learned in the engineering program to create a practical, real world solution to an engineering challenge.

The senior design competition helps to focus the senior students in increasing the quality and potential for commercial application for their design projects. Judges from local industry evaluate the projects …

Economic Analysis Of A Brackish Water Photovoltaic-Operated (Bwro-Pv) Desalination System, Ali Al-Karaghouli, Lawrence L. Kazmerski

Publications (E)

The photovoltaic (PV)-powered reverse-osmosis (RO) desalination system is considered one of the most promising technologies in producing fresh water from both brackish and sea water, especially for small systems located in remote areas. We analyze the economic viability of a small PV-operated RO system with a capacity of 5 m³/day used to desalinate brackish water of 4000 ppm total dissolve solids, which is proposed to be installed in a remote area of the Babylon governorate in the middle of Iraq; this area possesses excellent insolation throughout the year. Our analysis predicts very good economic and environmental benefits of …

Hrc Enews — 2010 Fall, Megan K. Svarz

Publications (HRC)

This issue contains staff accomplishments and announcements, event listings, and a "new faces" listing for new staff, affiliates, and researchers.

User's Guide To Mbc3: Multi-Blade Coordinate Transformation Code For 3-Bladed Wind Turbine, G. S. Bir

Publications (E)

The dynamics of wind turbine rotor blades are conventionally expressed in rotating frames attached to the individual blades. The tower-nacelle subsystem though, sees the combined effect of all rotor blades, not the individual blades. Also, the rotor responds as a whole to excitations such as aerodynamic gusts, control inputs, and tower-nacelle motion—all of which occur in a nonrotating frame. Multi-blade coordinate transformation (MBC) helps integrate the dynamics of individual blades and express them in a fixed (nonrotating) frame. MBC involves two steps: transforming the rotating degrees of freedom and transforming the equations of motion. Reference 1 details the MBC operation. …

Green Power Marketing In The United States: A Status Report (2009 Data), Lori Bird, Jenny Sumner

Publications (E)

This report documents green power marketing activities and trends in the United States. Aggregate green power sales data for all voluntary purchase markets across the United States are presented for 2009. The data presented in this report are based primarily on figures provided to NREL by utilities and independent renewable energy marketers. Because data cannot be obtained from all market participants, the estimates presented here likely represent an underestimate of the market size. Key trends identified in this year’s report include:
• In 2009, total retail sales of renewable energy in voluntary markets exceeded 30 million MWh, an increase of …

Development Of Streamflow Projections Under Changing Climate Conditions Over Colorado River Basin Headwaters, W. P. Miller, Thomas C. Piechota, S. Gangopadhyay, T. Pruitt

Civil and Environmental Engineering and Construction Faculty Research

The current drought over the Colorado River Basin has raised concerns that the US Department of the Interior, Bureau of Reclamation (Reclamation) may impose water shortages over the lower portion of the basin for the first time in history. The guidelines that determine levels of shortage are affected by forecasts determined by the Colorado Basin River Forecast Center (CBRFC). While these forecasts by the CBRFC are useful, water managers within the basin are interested in long-term projections of streamflow, particularly under changing climate conditions. In this study, a bias-corrected, statistically downscaled dataset of projected climate is used to force a …

Further Developments On The Geothermal System Scoping Model, Mark Antkowiak, Rosemary Sargent, Jesse W. Geiger

Publications (E)

The fields of well construction and engineering, power plant construction and engineering, and reservoir engineering often proceed independently of one another. Yet the subsystems of a geothermal plant with which each of these fields is concerned need to be integrated in order to create a viable geothermal power system and make enhanced (or engineered) geothermal systems (EGS) a technical and an economic reality. Furthermore, each of these subsystems need to be examined in the context of the overall power system to aid with plant construction, and–more salient to the U.S. Department of Energy–to help determine best investment of research dollars. …

Hrc Enews — 2010 Summer, Megan K. Svarz

Publications (HRC)

This issue contains staff accomplishments and announcements, event listings, and a "new faces" listing for new staff, affiliates, and researchers.

College Of Engineering Senior Design Competition Spring 2010, University Of Nevada, Las Vegas

Fred and Harriet Cox Senior Design Competition Projects

Each student in his or her senior year chooses, plans, designs, and prototypes a product in this required element of the curriculum. The senior design project encourages the student to use everything learned in the engineering program to create a practical, real-world solution to an engineering challenge.

A highlight of the year-long senior design project is the senior design competition. This competition, which usually takes place the week before finals each semester, helps focus the senior students on increasing the quality and potential for commercial application for their design projects.

Judges from local industry evaluate the projects on innovation, commercial …

Hrc Enews — 2010 Spring, Megan K. Svarz

Publications (HRC)

This issue contains staff accomplishments and announcements, event listings, a "new faces" listing for new staff, affiliates, and researchers, and an "of interest" section.

The Impacts Of Emergency Vehicle Signal Preemption On Urban Traffic Speed, Hualiang (Harry) Teng, Valerian Kwigizile, Gang Xie, Mohamed S. Kaseko, A. Reed Gibby

Civil and Environmental Engineering and Construction Faculty Research

We used GPS data from paratransit vehicles to evaluate the impact of emergency vehicles on urban traffic speeds. The results indicate that speed variance is significantly higher during emergency preemption and the mean speeds of traffic flowing in the same direction as the emergency vehicle and on crossing streets are lower during preemption than during normal conditions. Regression results indicate that traffic on major arterials and traffic in the opposite direction of the emergency vehicle tend to have higher speed during signal preemption. Signal preemption during peak periods and duration of preemption had a significant negative impact on traffic speeds. …

Solar Power And The Electric Grid, Energy Analysis, Nrel Energy Analysis

Publications (E)

In today’s electricity generation system, different resources make different contributions to the electricity grid. This fact sheet illustrates the roles of distributed and centralized renewable energy technologies, particularly solar power, and how they will contribute to the future electricity system. The advantages of a diversified mix of power generation systems are highlighted.

Barrier Coatings For Thin Film Solar Cells: Final Subcontract Report, L. C. Olsen

Publications (E)

This program has involved investigations of the stability of CdTe and copper-indium-gallium-diselenide (CIGS) solar cells under damp heat conditions and effects of barrier coatings. CdTe and CIGS cells were subjected to environmental conditions characterized by 60ºC and 90% relative humidity (60/90), and to some extent 85ºC and 85 % relative humidity (85/85). Barrier coating technology developed at PNNL for OLEDs was used to investigate approaches to encapsulation of the two types of thin film solar cells. Moisture barriers consisting of multi-layer coatings involving alternating layers of polymer and aluminum oxide were deposited directly onto the front surface of CIGS cells …

Consortia Focused On Photovoltaic R&D, Manufacturing, And Testing: A Review Of Existing Models And Structures, Charlie Coggeshall, Robert M. Margolis

Publications (E)

As the U.S. Department of Energy's (DOE's) Solar Energy Technologies Program prepares to initiate a new cost-shared research and development (R&D) effort on photovoltaic (PV) manufacturing, it is useful to review the experience to date with consortia focused on PV R&D, manufacturing, and testing. Information was gathered for this report by conducting interviews and accessing Web sites of 14 U.S. consortia and four European consortia, each with either a primary focus on or an emerging interest in PV technology R&D, manufacturing, or testing. Additional input was collected from several workshops held by the DOE and National Academy of Sciences (NAS) …

Random Approach To Optimization Of Overlay Public-Resource Computing Systems, Grzegorz Chmaj, Krzysztof Walkowiak

Electrical & Computer Engineering Faculty Research

The growing need for computationally demanding systems triggers the development of various network-oriented computing systems organized in a distributed manner. In this work we concentrate on one kind of such systems, i.e. public-resource computing systems. The considered system works on the top of an overlay network and uses personal computers and other relatively simple electronic equipment instead of supercomputers. We assume that two kinds of network flows are used to distribute the data in the public-resource computing systems: unicast and peer-to-peer. We formulate an optimization model of the system. After that we propose random algorithms that optimize jointly the allocation …

The Value Of Concentrating Solar Power And Thermal Energy Storage, Ramteen Sioshansi, Paul Denholm

Publications (E)

This paper examines the value of concentrating solar power (CSP) and thermal energy storage (TES) in four regions in the southwestern United States. Our analysis shows that TES can increase the value of CSP by allowing more thermal energy from a CSP plant’s solar field to be used, by allowing a CSP plant to accommodate a larger solar field, and by allowing CSP generation to be shifted to hours with higher energy prices. We analyze the sensitivity of CSP value to a number of factors, including the optimization period, price and solar forecasting, ancillary service sales, capacity value and dry …

Doe Request For Information (Rfi) De-Foa-0000153 Pv Manufacturing Initiative: Summary Report, National Renewable Energy Laboratory

Publications (E)

Clean Cities hosts a collection of tools on the exploring concepts for a “PV Manufacturing Initiative” to facilitate the development of a strong photovoltaic (PV) manufacturing industry in the United States. As an integral part this effort, and to inform the creation of a new funding opportunity in this area, DOE sought feedback from the PV industry.

This document summarizes the results of the PV Manufacturing Request for Information (RFI), DE-FOA-0000153. (See Attachment 1.) The RFI was posted on http://www.grants.gov on 4 September 2009 and the NREL Web site on 9 September 2009. Respondents were asked to submit RFI inputs …

Technology Improvement Pathways To Cost-Effective Vehicle Electrification: Preprint, A. Brooker, M. Thornton, J. Rugh

Publications (T)

Electrifying transportation can reduce or eliminate dependence on foreign fuels, emission of green house gases, and emission of pollutants. One challenge is finding a pathway for vehicles that gains wide market acceptance to achieve a meaningful benefit. This paper evaluates several approaches aimed at making plug-in electric vehicles (EV) and plug-in hybrid electric vehicles (PHEVs) cost-effective including opportunity charging, replacing the battery over the vehicle life, improving battery life, reducing battery cost, and providing electric power directly to the vehicle during a portion of its travel. Many combinations of PHEV electric range and battery power are included. For each case, …

Integrated Vehicle Thermal Management For Advanced Vehicle Propulsion Technologies: Preprint., K. Bennion, M. Thornton

Publications (T)

A critical element to the success of new propulsion technologies that enable reductions in fuel use is the integration of component thermal management technologies within a viable vehicle package. Vehicle operation requires vehicle thermal management systems capable of balancing the needs of multiple vehicle systems that may require heat for operation, require cooling to reject heat, or require operation within specified temperature ranges. As vehicle propulsion transitions away from a single form of vehicle propulsion based solely on conventional internal combustion engines (ICEs) toward a wider array of choices including more electrically dominant systems such as plug-in hybrid electric vehicles …

The Role Of Energy Storage With Renewable Electricity Generation, Paul Denholm, Erik Ela, Brendan Kirby, Michael Milligan

Publications (E)

Renewable energy sources, such as wind and solar, have vast potential to reduce dependence on fossil fuels and greenhouse gas emissions in the electric sector. Climate change concerns, state initiatives including renewable portfolio standards, and consumer efforts are resulting in increased deployments of both technologies. Both solar photovoltaics (PV) and wind energy have variable and uncertain (sometimes referred to as “intermittent”) output, which are unlike the dispatchable sources used for the majority of electricity generation in the United States. The variability of these sources has led to concerns regarding the reliability of an electric grid that derives a large fraction …

Analysis Of Hybrid Hydrogen Systems: Final Report, J. Dean, R. Braun, D. Munoz, M. Penev, C. Kinchin

Publications (E)

This project examined biomass pathways for hydrogen production and how they can be hybridized to support renewable electricity generation. The project considered many potential hybrid systems before narrowing the focus to two. The systems were studied in detail for process feasibility and economic performance. The best-performing system was estimated to produce hydrogen at a cost ($1.67/kg) within range of the Department of Energy target for central biomass-derived hydrogen production, while also providing value-added energy services to the electric grid.

2008 Solar Technologies Market Report, U.S. Department Of Energy

Publications (E)

This report focuses on the U.S. solar electricity market, including photovoltaic (PV) and concentrating solar power (CSP) technologies. The report provides an overview of global and U.S. installation trends. It also presents production and shipment data, material and supply chain issues, and solar industry employment trends. It also presents cost, price, and performance trends; and discusses policy and market drivers such as recently passed federal legislation, state and local policies, and developments in project financing. The final chapter provides data on private investment trends and near-term market forecasts.

Nrel: A Year In Clean Energy Innovations: A Review Of Nrel's Feature Stories, National Renewable Energy Laboratory

Publications (E)

The National Renewable Energy Laboratory (NREL) is the nation’s primary laboratory for renewable energy and energy efficiency research and development.

NREL’s mission and strategy are focused on advancing the U.S. Department of Energy’s and our nation’s energy goals. The laboratory’s scientists and researchers support critical market objectives to accelerate research from scientific innovations to market-viable alternative energy solutions. At the core of this strategic direction are NREL’s research and technology development competencies. These areas span from understanding renewable resources for energy, to the conversion of these resources to renewable electricity and fuels, and ultimately to the use of renewable electricity …

Wind Powering America: Fy09 Activities Summary, National Renewable Energy Laboratory

Publications (E)

The Wind Powering America FY09 Activities Summary reflects the accomplishments of state Wind Working Groups, WPA programs at the National Renewable Energy Laboratory, and partner organizations.

Hrc Enews — 2010 Winter, Megan K. Svarz

Publications (HRC)

This issue contains staff accomplishments and announcements, event listings, a "new faces" listing for new staff, affiliates, and researchers, and an "on the move" section listing new developments.

Real-Time On-Board Object Tracking For Cooperative Flight Control, Ajay Kumar Mandava, Emma Regentova, Henry Selvaraj

Electrical & Computer Engineering Faculty Research

One of possible cooperative Situations for flights could be a scenario when the decision on a new path is taken by A Certain fleet member, who is called the leader. The update on the new path is Transmitted to the fleet members via communication That can be noisy. An optical sensor can be used as a back-up for re-estimating the path parameters based on visual information. For A Certain topology, the issue can be solved by continuous tracking of the leader of the fleet in the video sequence and re-adjusting parameters of the flight, accordingly. To solve such a problem …

Giant Raman Enhancement On Nanoporous Gold Film By Conjugating With Nanoparticles For Single-Molecule Detection, Lihua Qian, Biswajit Das, Yan Li, Zhilin Yang

Electrical & Computer Engineering Faculty Research

Hot spots have the contradictively geometrical requirements for both the narrowest interstices to provide strong near-field coupling, and sufficient space to allow entrance of the analytes. Herein, a two-step method is employed to create hot spots within hybrid nanostructures, which consist of self-supported nanoporous gold films with the absorbed probes and subsequent nanoparticle conjugates without surface agents or mechanical motion. The molecules confined into 1 nm interstice exhibit 2.9 × 10⁷ times enhancement in Raman scattering compared to pure nanoporous gold. Giant enhancement primarily results from strong near-field coupling between nanopore and nanoparticle, which is theoretically confirmed by finite-difference …

On The Effect Of Hydrodynamic Slip On The Polarization Of A Nonconducting Spherical Particle In An Alternating Electric Field, Hui Zhao

Mechanical Engineering Faculty Research

The polarization of a charged, dielectric, spherical particle with a hydrodynamically slipping surface under the influence of a uniform alternating electric field is studied by solving the standard model (the Poisson–Nernst–Planck equations). The dipole moment characterizing the strength of the polarization is computed as a function of the double layer thickness, the electric field frequency, the particle’s surface charge, and the slip length. Our studies reveal that two processes contribute to the dipole moment: ion transport inside the double layer driven by the electric field and the particle’s electrophoretic motion. The hydrodynamic slip will simultaneously impact both processes. In the …

Electro-Osmotic Flow Over A Charged Superhydrophobic Surface, Hui Zhao

Mechanical Engineering Faculty Research

Bubbles can be trapped inside textured structures such as grooves, forming a superhydrophobic surface. A superhydrophobic surface has a large effective hydrodynamic slip length compared to a smooth hydrophobic surface and holds the promise of enhancing electrokinetic flows that find many interesting applications in microfluidics. However, recent theoretical studies suggested that electro-osmotic flows over a weakly charged superhydrophobic surface

the zeta potential of the surface is smaller than the thermal potential (25 mV) can only be enhanced when liquid-gas interfaces are charged [T. M. Squires, Phys. Fluids 20, 092105 (2008); Bahga et al., J. Fluid Mech. 644, 245 (2010)]. So …