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Performance enhancement using power beaming for electric propulsion earth orbital transporters

Description: An electric propulsion Earth orbital transport vehicle (EOTV) can effectively deliver large payloads using much less propellant than chemical transfer methods. By using an EOTV instead of a chemical upper stage, either a smaller launch vehicle can be used for the same satellite mass or larger satellite can be deployed using the same launch vehicle. However, the propellant mass savings from using the higher specific impulse of electric propulsion may not be enough to overcome the disadvantage of the added mass and cost of the electric propulsion power source. Power system limitations have been a major factor delaying the acceptance and use of electric propulsion. This paper outlines the power requirements of electric propulsion technology being developed today, including arcjets, magnetoplasmadynamic (MPD) thrusters, and ion engines. Power supply characteristics are discussed for nuclear, solar, and power-beaming systems. Operational characteristics are given for each, as are the impacts of the power supply alternative on the overall craft performance. Because of its modular nature, the power-beaming approach is able to meet the power requirements of all three electric propulsion types. Also, commonality of approach allows different electric propulsion approaches to be powered by a single power supply approach. Power beaming exhibits better flexibility and performance than on-board nuclear or solar power systems.
Date: August 1, 1991
Creator: Dagle, J.E.
Partner: UNT Libraries Government Documents Department

The PEGASUS Drive: A nuclear electric propulsion system for the space exploration initiative

Description: The advantages of using electric propulsion for propulsion are well-known in the aerospace community. The high specific impulse, lower propellant requirements, and lower system mass make it a very attractive propulsion option for the Space Exploration Initiative (SEI), especially for the transport of cargo. One such propulsion system is the PEGASUS Drive (Coomes et al. 1987). In its original configuration, the PEGASUS Drive consisted of a 10-MWe power source coupled to a 6-MW magnetoplasmadynamic (MPD) thruster system. The PEGASUS Drive propelled a manned vehicle to Mars and back in 601 days. By removing the crew and their associated support systems from the spacecraft and by incorporating technology advances in reactor design and heat rejection systems, a second generation PEGASUS Drive can be developed with an alpha less than two. Utilizing this propulsion system, a 400-MT cargo vehicle, assembled and loaded in low Earth orbit (LEO), could deliver 262 MT of supplies and hardware to Mars 282 days after escaping Earth orbit. Upon arrival at Mars the transport vehicle would place its cargo in the desired parking orbit around Mars and then proceed to synchronous orbit above the desired landing sight. Using a laser transmitter, PEGASUS would provide 2-MWe on the surface to operate automated systems deployed earlier and then provide surface power to support crew activities after their arrival. The additional supplies and hardware, coupled with the availability of megawatt levels of electric power on the Mars surface, would greatly enhance and even expand the mission options being considered under SEI. 9 refs., 1 fig., 1 tab.
Date: October 1, 1990
Creator: Coomes, E.P. & Dagle, J.E.
Partner: UNT Libraries Government Documents Department

Impacts of the distributed utility on transmission system stability

Description: The distributed (or dispersed) utility concept is rapidly becoming a reality in some service areas. In this framework, modular generation and storage assets along with selected demand-side management programs are used in place of the more traditional infrastructure upgrades to ensure reliable service to a group of utility customers. From among the many technical challenges associated with the proliferation of distributed resources, this paper deals with the impacts of distributed architectures upon the bulk transmission system. Bulk transmission system transient and small-signal stability are addressed through the use of extensive case studies. Planning tools and methods are discussed, and some general conclusions related to stability issues are drawn.
Date: July 1, 1995
Creator: Donnelly, M.K.; Dagle, J.E.; Trudnowski, D.J. & Rogers, G.J.
Partner: UNT Libraries Government Documents Department

High-temperature superconducting transformer evaluation

Description: The advancing development of high-temperature superconducting (HTS) materials is encouraging the evaluation of many practical applications. This paper summarizes a study that examined the future potential of HTS power transformers in the 30-MVA to 1000-MVA capacity range. Transformer performance was characterized on the basis of potentially achievable HTS materials capabilities and dominant transformer design parameters. Life-cycle costs were estimated and compared with those of conventional transformers to evaluate the economic viability and market potential of HTS designs. HTS transformers are projected to have both capital and energy cost advantages attributable to their ability to be intrinsically smaller and lighter than conventional transformers of comparable capacity.
Date: April 1, 1995
Creator: DeSteese, J.G.; Dagle, J.E. & Dirks, J.A.
Partner: UNT Libraries Government Documents Department

An integrated mission approach to the space exploration initiative will ensure success

Description: The direction of the American space program, as defined by President Bush and the National Commission on Space, is to expand human presence into the solar system. Landing an American on Mars by the 50th anniversary of the Apollo 11 lunar landing is the goal. This challenge has produced a level of excitement among young Americans not seen for nearly three decades. The exploration and settlement of the space frontier will occupy the creative thoughts and energies of generations of Americans well into the next century. The return of Americans to the moon and beyond must be viewed as a national effort with strong public support if it is to become a reality. Key to making this an actuality is the mission approach selected. Developing a permanent presence in space requires a continual stepping outward from Earth in a logical progressive manner. If we seriously plan to go and to stay, then not only must we plan what we are to do and how we are to do it, we must address the logistic support infrastructure that will allow us to stay there once we arrive. A fully integrated approach to mission planning is needed if the Space Exploration Initiative (SEI) is to be successful. Only in this way can a permanent human presence in space be sustained. An integrated infrastructure approach would reduce the number of new systems and technologies requiring development. The resultant horizontal commonality of systems and hardware would reduce the direct economic impact of SEI while an early return on investment through technology spin-offs would be an economic benefit by greatly enhancing our international technical competitiveness. If the exploration, development, and colonization of space is to be affordable and acceptable, careful consideration must be given to such things as return on investment'' and commercial product potential'' ...
Date: October 1, 1990
Creator: Coomes, E.P.; Dagle, J.E.; Bamberger, J.A. & Noffsinger, K.E.
Partner: UNT Libraries Government Documents Department

An integrated mission planning approach for the space exploration initiative

Description: A fully integrated energy-based approach to mission planning is needed if the Space Exploration Initiative (SEI) is to succeed. Such an approach would reduce the number of new systems and technologies requiring development. The resultant horizontal commonality of systems and hardware would reduce the direct economic impact of SEI and provide an economic benefit by greatly enhancing our international technical competitiveness through technology spin-offs and through the resulting early return on investment. Integrated planning and close interagency cooperation must occur if the SEI is to achieve its goal of expanding the human presence into the solar system and be an affordable endeavor. An energy-based mission planning approach gives each mission planner the needed power, yet preserves the individuality of mission requirements and objectives while reducing the concessions mission planners must make. This approach may even expand the mission options available and enhance mission activities.
Date: January 1, 1992
Creator: Coomes, E.P.; Dagle, J.E.; Bamberger, J.A. & Noffsinger, K.E.
Partner: UNT Libraries Government Documents Department

Economic analysis of operating alternatives for the South Vandenberg Power Plant at Vandenberg Air Force Base, California

Description: Vandenberg Air Force Base (VAFB), located approximately 50 miles northwest of Santa Barbara, California, commissioned the Pacific Northwest Laboratory to conduct an economic analysis of operating alternatives of the South Vandenberg Power Plant (SVPP). Recent concern over SVPP operating and environmental costs prompted VAFB personnel to consider other means to support the Missile Operation Support Requirement (MOSR). The natural gas-fired SVPP was originally designed to support the Space Transportation System launch activities. With cancellation of this mission, the SVPP has been used to provide primary and backup electric power to support MOSR activities for the Space Launch Complexes. This document provides economic analysis in support of VAFB decisions about future operation of the SVPP. This analysis complied with the life-cycle cost (LCC) analytical approach detailed in 10 CFR 436, which is used in support of all Federal energy decisions. Many of the SVPP operational and environmental cost estimates were provided by VAFB staff, with additional information from vendors and engineering contractors. The LCC analysis consisted of three primary operating strategies, each with a level of service equal to or better than the current status-quo operation. These scenarios are: Status-quo operation where the SVPP provides both primary and backup MOSR power; Purchased utility power providing primary MOSR support with backup power provided by an Uninterruptible Power Supply (UPS) system. The SVPP would be used to provide power for long-duration power outages; Purchased utility power provides primary MOSR support with backup power provided by a UPS system. A new set of dedicated generators would provide backup power for long-duration power outages.
Date: February 1, 1993
Creator: Daellenbach, K.K.; Dagle, J.E.; Reilly, R.W. & Shankle, S.A.
Partner: UNT Libraries Government Documents Department

An integrated mission planning approach for the Space Exploration Initiative

Description: This report discusses a fully integrated energy-based approach to mission planning which is needed if the Space Exploration Initiative (SEI) is to succeed. Such an approach would reduce the number of new systems and technologies requiring development. The resultant horizontal commonality of systems and hardware would reduce the direct economic impact of SEI and provide an economic benefit by greatly enhancing our international technical competitiveness through technology spin-offs and through the resulting early return on investment. Integrated planning and close interagency cooperation must occur if the SEI is to achieve its goal of expanding the human presence into the solar system and be an affordable endeavor. An energy-based mission planning approach gives each mission planner the needed power, yet preserves the individuality of mission requirements and objectives while reducing the concessions mission planners must make. This approach may even expand the mission options available and enhance mission activities.
Date: August 1, 1992
Creator: Coomes, E.P.; Dagle, J.E.; Bamberger, J.A. & Noffsinger, K.E.
Partner: UNT Libraries Government Documents Department

End-use load control for power system dynamic stability enhancement

Description: Faced with the prospect of increasing utilization of the transmission and distribution infrastructure without significant upgrade, the domestic electric power utility industry is investing heavily in technologies to improve network dynamic performance through a program loosely referred to as Flexible AC Transmission System (FACTS). Devices exploiting recent advances in power electronics are being installed in the power system to offset the need to construct new transmission lines. These devices collectively represent investment potential of several billion dollars over the next decade. A similar development, designed to curtail the peak loads and thus defer new transmission, distribution, and generation investment, falls under a category of technologies referred to as demand side management (DSM). A subset of broader conservation measures, DSM acts directly on the load to reduce peak consumption. DSM techniques include direct load control, in which a utility has the ability to curtail specific loads as conditions warrant. A novel approach has been conceived by Pacific Northwest National Laboratory (PNNL) to combine the objectives of FACTS and the technologies inherent in DSM to provide a distributed power system dynamic controller. This technology has the potential to dramatically offset major investments in FACTS devices by using direct load control to achieve dynamic stability objectives. The potential value of distributed versus centralized grid modulation has been examined by simulating the western power grid under extreme loading conditions. In these simulations, a scenario is analyzed in which active grid stabilization enables power imports into the southern California region to be increased several hundred megawatts beyond present limitations. Modeling results show distributed load control is up to 30 percent more effective than traditional centralized control schemes in achieving grid stability.
Date: February 1, 1997
Creator: Dagle, J. E.; Winiarski, D. W. & Donnelly, M. K.
Partner: UNT Libraries Government Documents Department

Electric power substation capital costs

Description: The displacement or deferral of substation equipment is a key benefit associated with several technologies that are being developed with the support of the US Department of Energy`s Office of Utility Technologies. This could occur, for example, as a result of installing a distributed generating resource within an electricity distribution system. The objective of this study was to develop a model for preparing preliminary estimates of substation capital costs based on rudimentary conceptual design information. The model is intended to be used by energy systems analysts who need ``ballpark`` substation cost estimates to help establish the value of advanced utility technologies that result in the deferral or displacement of substation equipment. This cost-estimating model requires only minimal inputs. More detailed cost-estimating approaches are recommended when more detailed design information is available. The model was developed by collecting and evaluating approximately 20 sets of substation design and cost data from about 10 US sources, including federal power marketing agencies and private and public electric utilities. The model is principally based on data provided by one of these sources. Estimates prepared with the model were compared with estimated and actual costs for the data sets received from the other utilities. In general, good agreement (for conceptual level estimating) was found between estimates prepared with the cost-estimating model and those prepared by the individual utilities. Thus, the model was judged to be adequate for making preliminary estimates of typical substation costs for US utilities.
Date: December 1997
Creator: Dagle, J. E. & Brown, D. R.
Partner: UNT Libraries Government Documents Department

Beam-powered lunar rover design

Description: Manned exploration of our nearest neighbors in the solar systems is the primary goal of the Space Exploration Initiative (SEI). An integral part of any manned lunar or planetary outpost will be a system for manned excursions over the surface of the planet. This report presents a preliminary design for a lunar rover capable of supporting four astronauts on long-duration excursions across the lunar landscape. The distinguishing feature of this rover design is that power is provided to rover via a laser beam from an independent orbiting power satellite. This system design provides very high power availability with minimal mass on the rover vehicle. With this abundance of power, and with a relatively small power-system mass contained in the rover, the vehicle can perform an impressive suite of mission-related activity. The rover might be used as the first outpost for the lunar surface (i.e., a mobile base). A mobile base has the advantage of providing extensive mission activities without the expense of establishing a fixed base. This concept has been referred to as Rove First.'' A manned over, powered through a laser beam, has been designed for travel on the lunar surface for round-trip distances in the range of 1000 km, although the actual distance traveled is not crucial since the propulsion system does not rely on energy storage. The life support system can support a 4-person crew for up to 30 days, and ample power is available for mission-related activities. The 8000-kg rover has 30 kW of continuous power available via a laser transmitter located at the Earth-moon L1 libration point, about 50,000 km above the surface of the moon. This rover, which is designed to operate in either day or night conditions, has the flexibility to perform a variety of power-intensive missions. 24 refs.
Date: March 1, 1992
Creator: Dagle, J.E.; Coomes, E.P.; Antoniak, Z.I.; Bamberger, J.A.; Bates, J.M.; Chiu, M.A. et al.
Partner: UNT Libraries Government Documents Department

Fort Drum integrated resource assessment

Description: The US Army Forces Command (FORSCOM) has tasked Pacific Northwest Laboratory (PNL) as the lead laboratory supporting the US Department of Energy (DOE) Federal Energy Management Program's (FEMP) mission to identify, evaluate, and assist in acquiring all cost-effective energy projects at Fort Drum. This is a model program PNL is designing for federal customers served by the Niagara Mohawk Power Company (Niagara Mohawk). It will (1) identify and evaluate all electric and fossil fuel cost-effective energy projects; (2) develop a schedule at each installation for project acquisition considering project type, size, timing, capital requirements, as well as energy and dollar savings; and (3) secure 100% of the financing required to implement electric energy efficiency projects from Niagara Mohawk and have Niagara Mohawk procure the necessary contractors to perform detailed audits and install the technologies. This report provides the results of the fossil fuel and electric energy resource opportunity (ERO) assessments performed by PNL at one of Niagara Mohawk's primary federal facilities, the FORSCOM Fort Drum facility located near Watertown, New York. It is a companion report to Volume 1, the Executive Summary, and Volume 2, the Baseline Detail.
Date: December 1, 1992
Creator: Dixon, D.R.; Armstrong, P.R.; Daellenbach, K.K.; Dagle, J.E.; Di Massa, F.V.; Elliott, D.B. et al.
Partner: UNT Libraries Government Documents Department

Benefit/cost comparisons of SMES in system-specific application scenarios

Description: The inherently high storage efficiency, instantaneous dispatch capability and multi-function uses of superconducting magnetic energy storage (SMES) are attributes that give it the potential for widespread application in the electric utility industry. Opportunities appear to exist where SMES at a given location could provide multiple benefits either simultaneously or sequentially as system conditions dictate. These benefits, including diurnal storage and system stability and dynamic control enhancement, increase the application potential of SMES to a larger number of opportunities than might be justified by the value of its diurnal storage capability alone. However, the benefits an individual utility may realize from SMES applications are strongly influenced by the characteristics of the utility system, the location of the SMES unit and the timing of its installation in the system. Such benefits are typically not evaluated adequately in generic studies. This paper summarizes results of case studies performed by Pacific Northwest Laboratory (PNL) with funding provided by the Bonneville Power Administration (BPA) and the Electric Power Research Institute (EPRI). The derivation of SMES benefits and costs are described and benefit/cost (B/C) ratios are compared in system-specific scenarios of interest to BPA. Results of using the DYNASTORE production cost model show the sensitivity of B/C ratios to SMES capacity and power and to the forecast system load. Intermediate-size SMES applications which primarily provide system stability and dynamic control enhancement are reviewed. The potential for SMES to levelize the output of a wind energy complex is also assessed. Most of the cases show SMES to provide a positive net benefit with the additional, sometimes surprising indication, that B/C ratios and net present worth of intermediate-size units can exceed those of larger systems.
Date: September 1, 1992
Creator: De Steese, J.G.; Dagle, J.E.; Kreid, D.K. (Pacific Northwest Lab., Richland, WA (United States)); Haner, J.M. & Myers, W.E. (Bonneville Power Administration, Portland, OR (United States))
Partner: UNT Libraries Government Documents Department