Publications

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Design Studies for Deep-Water Floating Offshore Vertical Axis Wind Turbines

Griffith, D.T.; Barone, Matthew F.; Paquette, Joshua P.; Owens, Brian C.; Bull, Diana L.; Simao-Ferriera, Carlos S.; goupee, andrew g.; Fowler, Matt F.

Deep - water offshore sites are an untapped opportunity to bring large - scale offshore wind energy to coastal population centers. The primary challenge has been the projected high costs for floating offshore wind systems. T his work presents a comprehensive investigat ion of a new opportunity for deep - water offshore wind using large - scale vertical axis wind turbines. Owing to inherent features of this technology , t here is a potential transformational opportunity to address the major cost drivers for floating w ind using vertical axis wind turbines . T he focus of this report is to evaluate the technical potential for this new technology. The approach to evaluating this potential wa s to perform system design studies focused on improving the understanding of technical performance parameters while l ooking for cost reduction opportunities. VAWT design codes we re developed in order to perform these design studies. To gain a better understanding of the desi gn space for floating VAWT systems , a comprehensive design study of multiple rotor configuration options was carried out . Floating platforms and moorings were then sized and evaluated for each of the candidate rotor configurations . Preliminary LCOE estimates and LCOE ranges were produced based on the design stu dy results for each of the major turbine and system components . The major outcomes of this study are a comprehensive technology assessment of VAWT performance and preliminary LCOE estimates that demonstrate that floating VAWTs may have favorable performanc e and costs in comparison to conventional HAWTs in the deep - water offshore environment where floating systems are required , indicating that this new technology warrants further study .

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Electrical cable utilization for wave energy converters

Journal of Ocean Engineering and Marine Energy

Bull, Diana L.; Baca, Michael J.; Schenkman, Benjamin L.

This paper investigates the suitability of sizing the electrical export cable based on the rating of the contributing WECs within a farm. These investigations have produced a new methodology to evaluate the probabilities associated with peak power values on an annual basis. It has been shown that the peaks in pneumatic power production will follow an exponential probability function for a linear model. A methodology to combine all the individual probability functions into an annual view has been demonstrated on pneumatic power production by a Backward Bent Duct Buoy (BBDB). These investigations have also resulted in a highly simplified and perfunctory model of installed cable cost as a function of voltage and conductor cross-section. This work solidifies the need to determine electrical export cable rating based on expected energy delivery as opposed to device rating as small decreases in energy delivery can result in cost savings.

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Sandia National Laboratories Strategic Context Workshop Series 2017: National Security Futures for Strategic Thinking

Keller, Elizabeth J.; Roll, Elizabeth R.; Aamir, Munaf S.; Bull, Diana L.; Deland, Sharon M.; Haddal, Chad H.; Passell, Howard D.; Foley, John T.; Harwell, Amber S.; Otis, Monique O.; Backus, George A.; Jones, Wendell J.; Bawden, Michael G.; Craft, Richard L.; Kistin, David J.; Martin, Jeffrey B.; McNicol, Bradley R.; Vannoni, Michael G.; Trost, Lawrence C.; Tsao, Jeffrey Y.; Weaver, Karla W.

In August 2017, Sandia convened five workshops to explore the future of advanced technologies and global peace and security through the lenses of deterrence, information, innovation, nonproliferation, and population and Earth systems.

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Reducing Future International Chemical and Biological Dangers

Haddal, Chad H.; Bull, Diana L.; Hernandez, Patricia M.; Foley, John T.

The International Biological and Chemical Threat Reduction Program at Sandia National Laboratories is developing a 15 - year technology road map in support the United States Government efforts to reduce international chemical and biological dangers . In 2017, the program leadership chartered an analysis team to explore dangers in the future international chemical and biological landscape through engagements with national security experts within and beyond Sandia to gain a multidisciplinary perspective on the future . This report offers a hi gh level landscape of future chemical and biological dangers based upon analysis of those engagements and provides support for further technology road map development.

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Technology Performance Level Assessment Methodology

Roberts, Jesse D.; Bull, Diana L.; Malins, Robert J.; Costello, Ronan P.; Babarit, Aurelien B.; Nielsen, Kim N.; Ferreira, Claudio B.; Kennedy, Ben K.; Dykes, Kathryn D.; Weber, Jochem W.

The technology performance level (TPL) assessments can be applied at all technology development stages and associated technology readiness levels (TRLs). Even, and particularly, at low TRLs the TPL assessment is very effective as it, holistically, considers a wide range of WEC attributes that determine the techno-economic performance potential of the WEC farm when fully developed for commercial operation. The TPL assessment also highlights potential showstoppers at the earliest possible stage of the WEC technology development. Hence, the TPL assessment identifies the technology independent “performance requirements.” In order to achieve a successful solution, the entirety of the performance requirements within the TPL must be considered because, in the end, all the stakeholder needs must be achieved. The basis for performing a TPL assessment comes from the information provided in a dedicated format, the Technical Submission Form (TSF). The TSF requests information from the WEC developer that is required to answer the questions posed in the TPL assessment document.

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Technical Submission Form: Technical Specification of a Wave Energy Farm

Roberts, Jesse D.; Nielsen, Kim N.; Kennedy, Ben K.; Bull, Diana L.; Costello, Ronan P.; Weber, Jochem W.

The Wave - SPARC project developed the Technology Performance Level (TPL) assessment procedure based on a rigorous Systems Engineering exercise. The TPL assessment allows a whole system evaluation of Wave Energy Conversion Technology by measuring it against the requirements determined through the Systems Engineering exercise. The TPL assessment is intended to be useful in technology evaluation; in technology innovation; in allocation of public or priva te investment, and; in making equipment purchasing decisions. This Technical Submission Form (TSF) serves the purpose of collecting relevant and complete information, in a technology agnostic way, to allow TPL assessment s to be made by third party assessor s. The intended usage of this document is that the organization or people that are performing the role of developers or promoters of a particular technology will use this form to provide the information necessary for the organization or people who are perf orming the assessor role to use the TPL assessment.

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Systems Engineering Applied to the Development of a Wave Energy Farm

Roberts, Jesse D.; Bull, Diana L.; Costello, Ronan P.; Babarit, Aurelien B.; Nielsen, Kim N.; Ferreira, Claudio B.; Kennedy, Ben K.; Malins, Robert J.; Dykes, Kathryn D.; Weber, Jochem W.

A motivation for undertaking this stakeholder requirements analysis and Systems Engineering exercise is to document the requirements for successful wave energy farms to facilitate better design and better design assessments. A difficulty in wave energy technology development is the absence to date of a verifiable minimum viable product against which the merits of new products might be measured. A consequence of this absence is that technology development progress, technology value, and technology funding have largely been measured, associated with, and driven by technology readiness, measured in technology readiness levels (TRLs). Originating primarily from the space and defense industries, TRLs focus on procedural implementation of technology developments of large and complex engineering projects, where cost is neither mission critical nor a key design driver. The key deficiency with the TRL approach in the context of wave energy conversion is that WEC technology development has been too focused on commercial readiness and not enough on the stakeholder requirements and particularly economic viability required for market entry.

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Wave energy prize experimental sea state selection

Proceedings of the International Conference on Offshore Mechanics and Arctic Engineering - OMAE

Bull, Diana L.; Dallman, Ann R.

A detailed methodology was used to select the sea states tested in the final stage of the Wave Energy Prize (WEPrize), a public prize challenge sponsored by the U.S. Department of Energy [1]. The winner was selected based on two metrics: a threshold value expressing the benefit to effort ratio (ACE metric) and a second metric which included hydrodynamic performance-related quantities (HPQ). HPQ required additional sea states to query aspects of the techno-economic performance not addressed by ACE. Due to the nature of the WEPrize, limited time was allotted to each contestant for testing and thus a limitation on the total sea states was required. However, the applicability of these sea states was required to encompass seven deployment locations representative of the United States West Coast and Hawaii. A cluster analysis was applied to scatter diagrams in order to determine a subset of sea states that could be scaled to find the average annual power flux at each wave climate for the ACE metric. Four additional sea states were selected, including two highly energetic sea states and two bimodal sea states, to evaluate HPQ. These sea states offer a common experimental testing platform for performance in United States deployment climates.

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Results 26–50 of 95
Results 26–50 of 95