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Federal government, utility, manufacturer: A unique partnership for comprehensive water efficiency

Description: A partnership among the Federal government, a utility, and water efficient equipment manufacturers was developed in response to the Executive Order 12902, Energy and Efficiency in Federal Facilities, where water conservation is still a fairly undeveloped part of resource conservation in the Federal government. The Department of Energy`s Federal Energy Management Program (with the National Renewable Energy Laboratory) managed the project, bringing together the Environmental Protection Agency, General Services Administration and Bureau of Reclamation with Denver Water and four water use equipment manufacturers to install and test water-saving indoor and outdoor technologies at the Denver Federal Center. This paper will describe the process used to form this partnership and document the results and its potential impact.
Date: October 1, 1995
Creator: Mayo, K.
Partner: UNT Libraries Government Documents Department

Photovoltaic Cz Silicon Module Improvements

Description: Work focused on reducing the cost per watt of Cz silicon photovoltaic modules under Phase II of Siemens Solar Industries' DOE/NREL PVMaT 4A subcontract is described in this report. New module designs were deployed in this phase of the contract, improvements in yield of over 10% were realized, and further implementation of Statistical Process Control was achieved during this phase. Module configurations representing a 12% cost reduction per watt were implemented in small scale production under Phase II of this contract. Yield improvements are described in detail, yield sensitivity to wafer thickness is quantified, and the deployment of SPC in critical process steps is reported here.
Date: September 1, 1998
Creator: Jester, T. L.
Partner: UNT Libraries Government Documents Department

Virtual environmental applications for buried waste characterization technology evaluation report

Description: The project, Virtual Environment Applications for Buried Waste Characterization, was initiated in the Buried Waste Integrated Demonstration Program in fiscal year 1994. This project is a research and development effort that supports the remediation of buried waste by identifying and examining the issues, needs, and feasibility of creating virtual environments using available characterization and other data. This document describes the progress and results from this project during the past year.
Date: May 1, 1995
Partner: UNT Libraries Government Documents Department

Fatigue of Composite Material Beam Elements Representative of Wind Turbine Blade Substructure

Description: The database and analysis methods used to predict wind turbine blade structural performance for stiffness, static strength, dynamic response,and fatigue lifetime are validated through the design, fabrication, and testing of substructural elements. We chose a test specimen representative of wind turbine blade primary substructure to represent the spar area of a typical wind turbine blade. We then designed an I-beam with flanges and web to represent blade structure, using materials typical of many U.S.-manufactured blades. Our study included the fabrication and fatigue testing of 52 beams and many coupons of beam material. Fatigue lifetimes were consistent with predictions based on the coupon database. The final beam specimen proved to be a very useful tool for validating strength and lifetime predictions for a variety of flange and web materials, and is serving as a test bed to ongoing studies of structural details and the interaction between manufacturing and structural performance. Th e beam test results provide a significant validation of the coupon database and the methodologies for predicting fatigue of composite material beam elements.
Date: January 11, 1998
Creator: Mandell, J. F.; Samborsky, D. D.; Combs, D. W.; Scott, M. E. & Cairns, D. S. (Department of Chemical Engineering, Montana State University)
Partner: UNT Libraries Government Documents Department

Vibration Testing

Description: This sheet describes a mobile test van which allows engineers to conduct vibration testing on wind turbines anywhere in US. It houses a computer system and test equipment (96 accelerometers, shaker system, etc.).
Date: June 1, 1996
Partner: UNT Libraries Government Documents Department

Biofacts: Fueling a stronger economy. Renewable fuel solutions for petroleum refineries

Description: The DOE Biofuels Program is investigating processes to condition synthesis gas (syngas) produced from the gasification of biomass, coke, waste oils, and other inexpensive feedstocks and low-cost by-products. Syngas technologies offer refiners economical, flexible solutions to the challenges presented by today`s market forces and regulatory environment, such as: increasingly stringent environmental regulations that dictate the composition of petroleum products; increasingly sour crudes; increased coke production and hydrogen use resulting from heavier crude; increased disposal cost for coke and residuals oils; and decreasing hydrogen supply resulting from decreased catalytic reforming severity--a necessity to comply with requirements for reduced aromatic content. Most importantly, refiners can use the DOE syngas processes to upgrade refinery residuals and coke, which minimizes environmental problems and maximizes profitability. DOE`s solution also offers refiners the flexibility to economically supplement petroleum feedstocks with a wide variety of locally available renewable feedstocks that can be fed into the gasifier--feedstocks such as energy crops, municipal solid wastes, many industrial wastes, and agricultural by-products.
Date: July 1, 1995
Partner: UNT Libraries Government Documents Department

CleanFleet. Final report: Volume 7, vehicle emissions

Description: Measurements of exhaust and evaporative emissions from Clean Fleet vans running on M-85, compressed natural gas (CNG), California Phase 2 reformulated gasoline (RFG), propane gas, and a control gasoline (RF-A) are presented. Three vans from each combination of vehicle manufacturer and fuel were tested at the California Air Resources Board (ARB) as they accumulated mileage in the demonstration. Data are presented on regulated emissions, ozone precursors, air toxics, and greenhouse gases. The emissions tests provide information on in-use emissions. That is, the vans were taken directly from daily commercial service and tested at the ARB. The differences in alternative fuel technology provide the basis for a range of technology options. The emissions data reflect these differences, with classes of vehicle/fuels producing either more or less emissions for various compounds relative to the control gasoline.
Date: December 1, 1995
Partner: UNT Libraries Government Documents Department

Wind turbine trailing-edge aerodynamic brake design

Description: This report describes the design of a centrifugally actuated aerodynamic-overspeed device for a horizontal-axis wind turbine. The device will meet the following criteria; (1) It will be effective for airfoil angles of attack 0{degrees} to 45{degrees}. (2) It will be stowed inside the blade profile prior to deployment. (3) It will be capable of offsetting the positive torque produced by the overall blade. (4) Hinge moments will be minimized to lower actuator loads and cost. (5) It will be evaluated as a potential power modulating active rotor-control system. A literature review of aerodynamic braking devices was conducted. Information from the literature review was used to conceptualize the most effective devices for subsequent testing and design. Wind-tunnel test data for several braking devices are presented in this report. Using the data for the most promising configuration, a preliminary design was developed for a MICON 65/13 wind turbine with Phoenix 7.9-m rotor blades.
Date: January 1, 1996
Creator: Quandt, G.
Partner: UNT Libraries Government Documents Department

Wind turbine trailing edge aerodynamic brakes

Description: Five trailing-edge devices were investigated to determine their potential as wind-turbine aerodynamic brakes, and for power modulation and load alleviation. Several promising configurations were identified. A new device, called the spoiler-flap, appears to be the best alternative. It is a simple device that is effective at all angles of attack. It is not structurally intrusive, and it has the potential for small actuating loads. It is shown that simultaneous achievement of a low lift/drag ratio and high drag is the determinant of device effectiveness, and that these attributes must persist up to an angle of attack of 45{degree}. It is also argued that aerodynamic brakes must be designed for a wind speed of at least 45 m/s (100 mph).
Date: April 1, 1995
Creator: Migliore, P G; Miller, L S & Quandt, G A
Partner: UNT Libraries Government Documents Department

Analysis of the fuel economy benefit of drivetrain hybridization

Description: Parallel- and series-configured hybrid vehicles likely feasible in next decade arc defined and evaluated using NREL's flexible ADvanced VehIcle SimulatOR ADVISOR. Fuel economics of these two diesel-powered hybrid vehicles are compared to a comparable-technology diesel- powered internal-combustion-engine vehicle. Sensitivities of these fuel economies to various vehicle and component parameters are determined and differences among them are explained. The fuel economy of the parallel hybrid defined here is 24% better than the internal- combustion-engine vehicle and 4% better than the series hybrid.
Date: January 1, 1997
Creator: Cuddy, M.R. & Wipke, K.B.
Partner: UNT Libraries Government Documents Department

Forest Products: Acoustic Humidity Sensor

Description: The new acoustic sensor, designed as a humidity-control system for the paper and textile industries, can both eliminate overdrying and improve product quality by measuring humidity precisely. This new fact sheet explains how the process works.
Date: January 29, 1999
Creator: Poole, L. & Recca, L.
Partner: UNT Libraries Government Documents Department

Fifth annual report to congress. Federal alternative motor fuels programs

Description: This report presents the status of the US Department of Energy`s alternative fuel vehicle demonstration and performance tracking programs being conducted in accordance with the Energy Policy and Conservation Act. These programs comprise the most comprehensive data collection effort ever undertaken on alternative transportation fuels and alternative fuel vehicles. The report summarizes tests and results from the fifth year. Electric vehicles are not included in these programs, and the annual report does not include information on them. Since the inception of the programs, great strides have been made in developing commercially viable alternative fuel vehicle technologies. However, as is the case in the commercialization of all new technologies, some performance problems have been experienced on vehicles involved in early demonstration efforts. Substantial improvements have been recorded in vehicle practicality, safety, and performance in real-world demonstrations. An aspect of particular interest is emissions output. Results from light duty alternative fuel vehicles have demonstrated superior inservice emissions performance. Heavy duty alternative fuel vehicles have demonstrated dramatic reductions in particulate emissions. However, emissions results from vehicles converted to run on alternative fuel have not been as promising. Although the technologies available today are commercially viable in some markets, further improvements in infrastructure and economics will result in greater market expansion. Information is included in this report on light and heavy duty vehicles, transit buses, vehicle conversions, safety, infrastructure support, vehicle availability, and information dissemination.
Date: September 1, 1996
Partner: UNT Libraries Government Documents Department

An examination of loads and responses of a wind turbine undergoing variable-speed operation

Description: The National Renewable Energy Laboratory has recently developed the ability to predict turbine loads and responses for machines undergoing variable-speed operation. The wind industry has debated the potential benefits of operating wind turbine sat variable speeds for some time. Turbine system dynamic responses (structural response, resonance, and component interactions) are an important consideration for variable-speed operation of wind turbines. The authors have implemented simple, variable-speed control algorithms for both the FAST and ADAMS dynamics codes. The control algorithm is a simple one, allowing the turbine to track the optimum power coefficient (C{sub p}). The objective of this paper is to show turbine loads and responses for a particular two-bladed, teetering-hub, downwind turbine undergoing variable-speed operation. The authors examined the response of the machine to various turbulent wind inflow conditions. In addition, they compare the structural responses under fixed-speed and variable-speed operation. For this paper, they restrict their comparisons to those wind-speed ranges for which limiting power by some additional control strategy (blade pitch or aileron control, for example) is not necessary. The objective here is to develop a basic understanding of the differences in loads and responses between the fixed-speed and variable-speed operation of this wind turbine configuration.
Date: November 1, 1996
Creator: Wright, A.D.; Buhl, M.L. Jr. & Bir, G.S.
Partner: UNT Libraries Government Documents Department

Some preliminary results from the NWTC direct-drive, variable-speed test bed

Description: With the remarkable rise in interest in variable-speed operation of larger wind turbines, it has become important for the National Wind Technology Center (NWTC) to have access to a variable-speed test bed that can be specially instrumented for research. Accordingly, a three-bladed, 10-meter, downwind, Grumman Windstream machine has been equipped with a set of composite blades and a direct-coupled, permanent-magnet, 20 kilowatt generator. This machine and its associated control system and data collection system are discussed. Several variations of a maximum power control algorithm have been installed on the control computer. To provide a baseline for comparison, several constant speed algorithms have also been installed. The present major effort is devoted to daytime, semi-autonomous data collection.
Date: October 1, 1996
Creator: Carlin, P.W. & Fingersh, L.J.
Partner: UNT Libraries Government Documents Department

Case studies of energy efficiency financing in the original five pilot states, 1993-1996

Description: The purpose of this report is to document progress in state-level programs in energy efficiency financing programs that are linked with home energy rating systems. Case studies are presented of programs in five states using a federal pilot program to amortize the costs of home energy improvements. The case studies present background information, describe the states` program, list preliminary evaluation data and findings, and discuss problems and solution encountered in the programs. A comparison of experiences in pilot states will be used to provide guidelines for program implementers, federal agencies, and Congress. 5 refs.
Date: May 1, 1997
Creator: Farhar, B. C.; Collins, N. E. & Walsh, R. W.
Partner: UNT Libraries Government Documents Department

Reducing VMTs through Transit-On-Demand with GPS and satellite communications

Description: As a partial solution to the problem of increasing foreign petroleum imports,urban congestion, and air pollution from automobiles, NREL researchers have successfully demonstrated a transportation concept called Transit-On-Demand (TOD). TOD uses the global positioning system (GPS) to locate all vehicles in a fleet, two-way communications between the vehicles and a central computer-server, and advanced dispatching and routing software to control the movement of vehicles within the fleet. Reducing the vehicle-miles-travelled (VMTs) through implementing efficient transportation systems such as TOD, results in less energy being required for transportation and a decrease in the amount of required imported petroleum. Through development of an advanced world wide web site and use of the new Java{trademark} Internet programming language, the demonstration allows visitors to the web site to see updates of vehicle position on a map every 20 seconds,while effectively minimizing the internet bandwidth required. The project demonstrates how a fixed-route, fixed- schedule shuttle can be converted to be demand-responsive to more effectively move people from where they are to where they want to be at the time they want to travel.
Date: October 1, 1996
Creator: Wipke, K.B.
Partner: UNT Libraries Government Documents Department

Aluminum: Aluminum Scrap Decoater

Description: NICE3 and the Philip Services Corporation are cost-sharing a demonstration project to decoat metal using indirect-fired controlled-atmosphere (IDEX) kilns, which can both process solid organics such as rubber and plastics, and minimize dust formation and emission of volatile organic compounds. The publication explains how this cost-effective, two-step system operates.
Date: January 29, 1999
Creator: Blazek, S.
Partner: UNT Libraries Government Documents Department

Deploying anaerobic digesters: Current status and future possibilities

Description: Unmanaged pollutants from putrescible farm, industrial, and municipal wastes degrade in the environment, and methane emitted from their decomposition may contribute to global climate change. Under modern environmental regulations, these wastes are becoming difficult to dispose of using traditional means. One waste management system, anaerobic digestion or AD, not only provides pollution prevention but can also convert a disposal problem into a new profit center. This report is drawn from a special session of the Second Biomass Conference of the Americas. Selected papers are indexed separately for inclusion in the Energy Science and Technology Database.
Date: January 1, 1996
Creator: Lusk, P.; Wheeler, P. & Rivard, C.
Partner: UNT Libraries Government Documents Department

Development of a photovoltaic module energy ratings methodology

Description: The National Renewable Energy Laboratory has begun work on developing a consensus-based approach to rating photovoltaic modules. This new approach was intended to address the limitations of the defacto standard module power rating at standard test conditions. Using technical input from a number of sources, and under the guidance of an industry-based technical review committee, the approach described in this paper was developed. The Module Energy Rating (MER) consists of 10 estimates of how much energy a single typical module of a particular type will produce in one day, one for each of 5 different weather/location combinations and 2 load-types. This paper presents an overview of the procedures required to generate an MER for any particular module type.
Date: May 1, 1995
Creator: Kroposki, B.; Mrig, L.; Whitaker, C. & Newmiller, J.
Partner: UNT Libraries Government Documents Department

The future of amorphous silicon photovoltaic technology

Description: Amorphous silicon modules are commercially available. They are the first truly commercial thin-film photovoltaic (PV) devices. Well-defined production processes over very large areas (>1 m{sup 2}) have been implemented. There are few environmental issues during manufacturing, deployment in the field, or with the eventual disposal of the modules. Manufacturing safety issues are well characterized and controllable. The highest measured initial efficiency to date is 13.7% for a small triple-stacked cell and the highest stabilized module efficiency is 10%. There is a consensus among researchers, that in order to achieve a 15% stabilized efficiency, a triple-junction amorphous silicon structure is required. Fundamental improvements in alloys are needed for higher efficiencies. This is being pursued through the DOE/NREL Thin-Film Partnership Program. Cost reductions through improved manufacturing processes are being pursued under the National Renewable Energy Laboratory/US Department of Energy (NREL/DOE)-sponsored research in manufacturing technology (PVMaT). Much of the work in designing a-Si devices is a result of trying to compensate for the Staebler-Wronski effect. Some new deposition techniques hold promise because they have produced materials with lower stabilized defect densities. However, none has yet produced a high efficiency device and shown it to be more stable than those from standard glow discharge deposited material.
Date: June 1, 1995
Creator: Crandall, R. & Luft, W.
Partner: UNT Libraries Government Documents Department

Power Flow Management in a High Penetration Wind-Diesel Hybrid Power System with Short-Term Energy Storage

Description: This paper is intended as an introduction to some of the control challenges faced by developers of high penetration wind-diesel systems, with a focus on the management of power flows in order to achieve precise regulation of frequency and voltage in the face of rapidly varying wind power input and load conditions. The control algorithms presented herein are being implemented in the National Renewable Energy Laboratory (NREL) high penetration wind-diesel system controller that will be installed in the village of Wales, Alaska, in early 2000.
Date: July 29, 1999
Creator: Drouilhet, S. M.
Partner: UNT Libraries Government Documents Department