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Jenne, Dale S.

Publications and source records attributed to Jenne, Dale S..

Performance of reverse osmosis membrane with large feed pressure fluctuations from a wave-driven desalination system

Wave-driven desalination systems are proposed water treatment systems that involve reverse osmosis of seawater powered directly by wave motion. Such a configuration would result in drastic feed pressure fluctuations. For a technology conventionally operated with a constant feed condition, the effect of these variable pressures on membrane integrity and performance is unknown. Here, experiments were conducted with spiral wound membranes coupled to a system capable of producing feed pressure fluctuations of more than 400 psi. Feed composition included 5, 20, and 35 g/L NaCl, and a synthetic seawater at normal and 1.5x concentration. The variable feed conditions included sine-like pressure waves swings of 200-500 and 500-900 psi with frequencies of 1.25, 7.5, and 12 waves/min, and a model-generated random waveform. Between each wave experiment we performed membrane integrity tests at 650 psi and 25 g/L NaCl feed, which showed a 7.4% drop in the membrane's water permeability coefficient, an 18.4% flux decline, and more than 99% salt rejection over 1770 h of cumulative experimental time. Analysis of permeate samples showed high salt rejection. In general, variable feed pressure had no significant deleterious effect on membrane integrity or performance.

16 TIDAL AND WAVE POWER↗

Research and Development Pathways for Powering the Blue Economy with Marine Renewable Energy

As marine renewable energy technology is adapted or designed for Blue Economy end-uses, challenges unique to operation at sea and in remote coastal areas must be addressed to meet demands distinct from utility grid electricity generation. Foundational research and development with this end goal is conducted to broadly enable the initiative of Powering the Blue Economy. Determination of distinct R\&D topics is informed by pathways including an engineering design customer-driven approach and feedback from the creation and administration of prize competitions in the Blue Economy technology space. Critical research outcomes, such as determining the performance of small wave energy converters and benchmarking the reliability for power systems at sea, are among the goals of ten foundational R\&D projects currently underway.

Cavagnaro, Robert J.↗

Powering the Blue Economy: Progress Exploring Marine Renewable Energy Integration With Ocean Observations

The blue economy is a dynamic and rapidly growing movement that captures the interplay between economic, social, and ecological sustainability of the ocean and encompasses numerous maritime sectors and activities (e.g., commerce and trade; living resources; renewable energy; minerals, materials, and freshwater; and ocean health and data). The demand for ocean data to inform scientific, risk reduction, and national security needs is leading to a large increase in the number of deployed ocean observation and monitoring systems, most of which require increased power. Because ocean observation systems are often placed in remote locations, they primarily rely on energy storage (or in some cases in situ energy generation) to power instruments and equipment, which imposes limits on sampling rates, deployment times, and spatiotemporal resolution of data. The U.S. Department of Energy Water Power Technologies Office is exploring the potential for marine renewable energy (MRE) devices (largely wave and tidal energy converters) to provide power to support multiple blue economy opportunities. A portion of these opportunities focus on power at sea markets for providing power in off-grid and offshore locations to support a variety of ocean-based activities, including ocean observation and navigation, underwater vehicle charging, marine aquaculture, marine algae farming, and seawater mining. Initially, research has focused on better understanding how and where MRE can provide a consistent source of reliable power to extend ocean observing missions, including operation of autonomous underwater vehicles. Online surveys as well as phone and inperson interviews were conducted with experts in the field of ocean observing systems and observatories to gather end-user requirements, determine energy needs, identify opportunities for codevelopment, and pinpoint constraints for MRE to meet those needs. The surveys and interviews provided feedback on the potential for powering devices and vehicles using MRE, including identifying common themes and challenges that will inform foundational research and development steps needed to advance the integration of MRE with ocean observing systems. In most cases, additional power generation on the order of watts was identified as significantly beneficial to enhancing ocean observations capabilities.

marine renewable energy, powering the blue economy↗

Enabling Marine Energy Integration for Ocean Observing: Functional Requirements

Marine renewable energy (i.e., wave, tidal or ocean current, thermal gradient, and salinity gradient) or MRE can revolutionize ocean observing capabilities. Five use cases representing a range of ocean observing platforms were developed based on end-user feedback. Drawing from these use cases, common needs or functional requirements were developed to help guide the integration of MRE power delivery for ocean observation structures and functions. The functional requirements were determined from descriptions of the use cases, specifications of hardware that are used or closely associated with existing ocean observation platforms, and direct feedback from ocean observation sensor/platform developers and users. Twenty types of functional requirements were identified, including those associated with power and energy use; physical system requirements; temperature and depth; electrical, acoustic, and motion interference; and reliability. Each set of functional requirements is illustrated as features of the use cases. By defining functional requirements for MRE technology integration in ocean observing platforms, and focusing on end-user requirements, barriers to developing MRE-driven ocean observation missions can be reduced.

Cavagnaro, Robert J.↗

Powering the Blue Economy - Ocean Observing Use Cases Report

The "Powering the Blue Economy" (PBE) Report identified ocean observing and autonomous underwater vehicle (AUV) recharge as near-term markets with significant potential for marine energy integration when specified qualitative and quantitative assessment criteria were used. The ocean observing market (including AUVs) scored high relative to other markets analyzed in the PBE Report with respect to market size, marine renewable energy (MRE) compatibility with functional requirements, competitive positioning (i.e., MRE versus other power sources), path to market, and alignment to the Department of Energy Water Power Technologies Office (WPTO) and other agencies' objectives. Based on this scoring, Pacific Northwest National Laboratory (PNNL) and the National Renewable Energy Laboratory (NREL) pursued the development of five use cases that represent a spectrum of ocean observation platforms, fixed and mobile, to explore the present and future power needs that might be satisfied by marine energy. The use cases were described and analyzed for this potential by examining current missions and future needs, evaluating the mix of renewable energy sources that might satisfy those needs at sea, and understanding the overall cost drivers that might enable this application.

14 SOLAR ENERGY↗

A Detailed Wind Turbine Blade Cost Model

This technical report describes a detailed blade cost model for wind turbine blades in the range of 30 to 100 meters in length. The model estimates the bill of materials, the number of labor hours and the cycle time, and the costs related to direct labor, overhead, buildings, tooling, equipment, maintenance, and capital. The model applies to multimegawatt wind turbine blades manufactured via vacuum-assisted resin transfer molding, which is the most commonly adopted manufacturing method for modern wind turbine blades. The model is implemented both in a large Excel file and in Python. The latter is freely available in the repository of the Wind-Plant Integrated System Design and Engineering Model (WISDEM[R]) github.com/WISDEM. WISDEM is a multidisciplinary analysis and optimization design framework developed at the National Renewable Energy Laboratory. This blade cost model represents a valuable tool to run design optimization studies for wind turbines. In this report, the model is first presented with its approach and assumptions and then computes the costs of three blades, namely the 33-meter-long Wind Partnership for Advanced Component Technologies (WindPACT) study blade, the 63-meter-long International Energy Agency (IEA) Wind Task 37 land-based reference wind turbine blade, and the 100-meter-long SNL-100-03 blade developed at Sandia National Laboratories.

17 WIND ENERGY↗

Existing Ocean Energy Performance Metrics

This document summarizes existing Marine and Hydrokinetic (MHK) performance metrics known to the United States Department of Energy and national laboratories. This document was updated based on feedback from the MHK Energy community, however, this summary still may not be exhaustive. There are a wide variety of needs and uses for metrics. All stakeholders, such as developers, funding agencies, investors, and researchers, have a need for metrics and their many uses. It is evident that the sector will benefit from clear techno economic performance metrics to guide development towards success. There are international efforts underway to bring the community together to (1) understand what metrics/approaches are being used currently and (2) reach a global framework on the approach to the measurement of success. This document serves to list existing metrics known to the U.S. at the present, and is not meant to represent international efforts or consensus.

16 TIDAL AND WAVE POWER↗

Evaluation of performance metrics for the Wave Energy Prize converters tested at 1/20 th scale

It is expected that wave energy technologies will play a future role in providing clean renewable energy and diversifying energy portfolios; however, they are still at an early stage of development compared to other renewables, with varying archetypes proposed. As technologies advance toward commercialization, benchmarking is needed to quantify performance and costs. In this review, experimental datasets of Wave Energy Converter (WEC) devices tested in the final stage of the Wave Energy Prize (WEPrize) are compared and ranked using performance metrics found in the literature and those developed as WEPrize judging metrics at both U.S. and European representative wave climates. Because the WEPrize devices were tested under a set of identical sea states, which ranged from typical operating conditions to extreme storm events, consistent datasets were produced to facilitate comparison. This allows for a rare addition to the open literature on device performance trends. In addition, a reevaluation of trends established in previous power performance benchmarking studies is given. Trends found in previous studies were confirmed, except for the absorbed energy per characteristic mass metric, in which some of the WEPrize devices had higher values. Each of the metrics considered in this study has limitations due to the assumptions in simplifying the economic potential (e.g., power absorbed vs. a proxy to cost). In addition, each of these proxies is limited to the capital cost of a device, unlike the final metric used in the WEPrize, HPQ, which includes limited proxies of operational and capital expenditures, as well as array considerations. Recommendations are given for the use and potential modification of the metrics considered. Specifically, it is recommended that the ACE metric (from the WEPrize) be modified to more accurately include the other important system costs, such as the PTO and mooring, as well as installation, operation and maintenance costs.

16 TIDAL AND WAVE POWER↗

Maritime Renewable Energy Markets: Power from the Sea

Marine renewable energy (MRE) is in the early stages of contributing to the energy portfolios of the US and many other nations around the world. Although many MRE developers are designing devices that will harvest energy to contribute to the electrical grid from waves, tides, and ocean currents, a number of other promising maritime markets could be supplied with MRE power at sea. These maritime markets are often less price sensitive than utility-scale electricity markets and can handle some degree of intermittency. Some of the promising maritime markets that could benefit from co-located power generation include ocean observation nodes, underwater recharge of autonomous vehicles, desalination of seawater for remote coastal areas, offshore aquaculture, shoreline protection and electricity generation, providing electricity and freshwater following coastal emergencies, providing power to islanded and isolated communities, powering and cooling nearshore of underwater data centers, recharging of electric surface vessels, and personal charging of electronics. Pairing of MRE power generation with these and other maritime markets is in the early stages, but the potential for synergy and growth of MRE coupled to these markets is promising.

Marine renewable energy↗

Methodology to Calculate the ACE and HPQ Metrics Used in the Wave Energy Prize

The U.S. Department of Energy's Wave Energy Prize Competition encouraged the development of innovative deep-water wave energy conversion technologies that at least doubled device performance above the 2014 state of the art. Because levelized cost of energy (LCOE) metrics are challenging to apply equitably to new technologies where significant uncertainty exists in design and operation, the prize technical team developed a reduced metric as proxy for LCOE, which provides an equitable comparison of low technology readiness level wave energy converter (WEC) concepts. The metric is called 'ACE' which is short for the ratio of the average climate capture width to the characteristic capital expenditure. The methodology and application of the ACE metric used to evaluate the performance of the technologies that competed in the Wave Energy Prize are explained in this report.

17 WIND ENERGY↗