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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 613 records · Page 34
All sourcesNASA NTRSDOE OSTI
DOE OSTI2013

Proton Beam Therapy and Accountable Care: The Challenges Ahead

Purpose: Proton beam therapy (PBT) centers have drawn increasing public scrutiny for their high cost. The behavior of such facilities is likely to change under the Affordable Care Act. We modeled how accountable care reform may affect the financial standing of PBT centers and their incentives to treat complex patient cases. Methods and Materials: We used operational data and publicly listed Medicare rates to model the relationship between financial metrics for PBT center performance and case mix (defined as the percentage of complex cases, such as pediatric central nervous system tumors). Financial metrics included total daily revenues and debt coverage (daily revenues − daily debt payments). Fee-for-service (FFS) and accountable care (ACO) reimbursement scenarios were modeled. Sensitivity analyses were performed around the room time required to treat noncomplex cases: simple (30 minutes), prostate (24 minutes), and short prostate (15 minutes). Sensitivity analyses were also performed for total machine operating time (14, 16, and 18 h/d). Results: Reimbursement under ACOs could reduce daily revenues in PBT centers by up to 32%. The incremental revenue gained by replacing 1 complex case with noncomplex cases was lowest for simple cases and highest for short prostate cases. ACO rates reduced this incremental incentive by 53.2% for simple cases and 41.7% for short prostate cases. To cover daily debt payments after ACO rates were imposed, 26% fewer complex patients were allowable at varying capital costs and interest rates. Only facilities with total machine operating times of 18 hours per day would cover debt payments in all scenarios. Conclusions: Debt-financed PBT centers will face steep challenges to remain financially viable after ACO implementation. Paradoxically, reduced reimbursement for noncomplex cases will require PBT centers to treat more such cases over cases for which PBT has demonstrated superior outcomes. Relative losses will be highest for those facilities focused primarily on treating noncomplex cases.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2012

Microporous Separators for Fe/V Redox Flow Batteries

The Fe/V redox flow battery has demonstrated promising performance that is advantageous over other redox flow battery systems. The less oxidative nature of the Fe(III) species enables use of hydrocarbon - based ion exchange membranes or separators. Daramic(reg. sign) microporous polyethylene separators were tested on Fe/V flow cells using the sulphuric/chloric mixed acid - supporting electrolytes. Among them, Daramic(reg. sign) C exhibited good flow cell cycling performance with satisfactory repeatability over a broad temperature range of 5 - 50 degrees C. Energy efficiency (EE) of C remains above 67% at current densities of 50 - 80 cm{sup -2} in the temperature range from room temperature to 50 degrees C. The capacity decay problem could be circumvented through hydraulic pressure balancing by applying different pump rates to the positive and negative electrolytes. Stable capacity and energy were obtained over 40 cycles at room temperature and 40 degrees C. These results manifest that the extremely low-cost separators ($10/cm2) are applicable in the Fe/V flow battery system at an acceptable sacrifice of energy efficiency. This stands for a remarkable breakthrough in significant reduction of the capital cost of the Fe/V flow battery system, and is promising to promote its market penetration in grid stabilization and renewable integration.

25 ENERGY STORAGE↗
DOE OSTI2012

Large Hybrid Energy Systems for Making Low CO2 Load-Following Power and Synthetic Fuel

Hybrid energy systems using nuclear heat sources can economically produce load-following electrical power by exploiting the surplus generation capacity available at night or seasonally to make synthetic fuel. Vehicle fuel is the only current energy use large enough to absorb all the energy capacity that might be diverted from the power industry, and its ease of storage obviates problems with discontinuous synfuel production. The potential benefits and challenges of synfuels integration are illustrated by the production of methanol from natural gas (as a source of carbon) using steam from a light water nuclear power reactor which is assumed to be available in accord with a year's worth of power demand data. Methanol's synthesis process is easily adapted to using 300 C heat from a light water reactor and this simple compound can be further processed into gasoline, biodiesel, or dimethyl ether, fuels which can be used with the current vehicle fleet. A supplemental feed to the methanol process of natural gas (for energy) allows operation at constant full rate when the nuclear heat is being used to produce electrical power. The higher capital costs of such a system are offset by a lower cost of heat and power production from a large base load type of plant and by reduced costs associated with much lower CO2 emissions. Other less tangible economic benefits of this and similar hybrid systems include better use of natural resource for fuels and greater energy services security from the domestic production of vehicle fuel.

02 PETROLEUM↗
DOE OSTI2010

OPTIMIZATION OF LONG RURAL FEEDERS USING A GENETIC ALGORITHM

This paper describes the optimization of conductor size and the voltage regulator location and magnitude of long rural distribution lines. The optimization minimizes the lifetime cost of the lines, including capital costs and losses while observing voltage drop and operational constraints using a Genetic Algorithm (GA). The GA optimization is applied to a real Single Wire Earth Return (SWER) network in regional Queensland and results are presented.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2014

Unraveling chaotic attractors by complex networks and measurements of stock market complexity

We present a novel method for measuring the complexity of a time series by unraveling a chaotic attractor modeled on complex networks. The complexity index R, which can potentially be exploited for prediction, has a similar meaning to the Kolmogorov complexity (calculated from the Lempel–Ziv complexity), and is an appropriate measure of a series' complexity. The proposed method is used to research the complexity of the world's major capital markets. None of these markets are completely random, and they have different degrees of complexity, both over the entire length of their time series and at a level of detail. However, developing markets differ significantly from mature markets. Specifically, the complexity of mature stock markets is stronger and more stable over time, whereas developing markets exhibit relatively low and unstable complexity over certain time periods, implying a stronger long-term price memory process.

97 MATHEMATICS AND COMPUTING↗
DOE OSTI2015

Carbon-ion cancer therapy shows promise

Radiation-resistant tumors are targets for heavy-ion particles. But high capital costs have prevented construction of treatment facilities in the US.

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTAN↗
DOE OSTI2012

Absorber Alignment Measurement Tool for Solar Parabolic Trough Collectors: Preprint

As we pursue efforts to lower the capital and installation costs of parabolic trough solar collectors, it is essential to maintain high optical performance. While there are many optical tools available to measure the reflector slope errors of parabolic trough solar collectors, there are few tools to measure the absorber alignment. A new method is presented here to measure the absorber alignmentin two dimensions to within 0.5 cm. The absorber alignment is measured using a digital camera and four photogrammetric targets. Physical contact with the receiver absorber or glass is not necessary. The alignment of the absorber is measured along its full length so that sagging of the absorber can be quantified with this technique. The resulting absorber alignment measurement provides criticalinformation required to accurately determine the intercept factor of a collector.

14 SOLAR ENERGY↗
DOE OSTI2014

Sci—Fri PM: Topics — 03: The Global Task Force on Radiotherapy for Cancer Control: Core Investments

The Union for International Cancer Control (UICC) is a membership-based, non-governmental organization with a mandate to “…to unite the cancer community to reduce the global cancer burden, to promote greater equity, and to integrate cancer control into the world health and development agenda.” COMP is an associate member of the UICC. It is well recognized by the UICC that there are major gaps between high, and low and middle income countries, in terms of access to cancer services including access to radiation therapy. In this context, the UICC has developed a Global Task Force on Radiotherapy for Cancer Control with a charge to answer a single question: “What does it cost to close the gap between what exists today and reasonable access to radiotherapy globally?” The Task Force consists of leaders internationally recognized for their radiation treatment related expertise (radiation oncologists, medical physicists, radiation therapists) as well as those with global health and economics specialization. The Task Force has developed three working groups: (1) to look at the global burden of cancer; (2) to look at the infrastructure requirements (facilities, equipment, personnel); and (3) to consider outcomes in terms of numbers of lives saved and palliated patients. A report is due at the World Cancer Congress in December 2014. This presentation reviews the infrastructure considerations under analysis by the second work group. The infrastructure parameters being addressed include capital costs of buildings and equipment and operating costs, which include human resources, equipment servicing and quality control, and general overhead.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2023

Renewable Energy Potential Model: Geothermal Supply Curves

The Renewable Energy Potential (reV) model is a geospatial platform for estimating technical potential and developing renewable energy supply curves, initially developed for wind and solar technologies. The model evaluates deployment constraints, considering land use, environmental, and cultural factors, and estimates the distance to existing grid features to connect future plants (Maclaurin et al., 2021). A pressing deficiency in the reV model, however, is representation of geothermal electricity generation technologies. To address this gap, we developed a novel geothermal generation module for reV that allows for representation and analysis at the same level of detail as other renewable technologies. The included paper describes our process for evaluating data sources for the modeling, and presents five preliminary reV geothermal results. More specifically, we present two sets of resource data that represent upper and lower bounds for geothermal potential. We then present several sensitivity runs using the upper bound resource data; the results are encouraging that levelized cost of electricity (LCOE) can be reduced by optimizing the location and estimated capacity of the spatially diverse geothermal resource while considering the distance to existing grid infrastructure. Our preliminary supply curves and levelized cost of electricity (LCOE) results provided here should be considered with care due to the high uncertainty in geothermal resource potential data. We present median LCOE values for the conterminous U.S. for three scenarios: two hydrothermal (3.5km depth, USGS heat flow & SMU temperatures respectively) and one EGS (4.5km depth, SMU temperatures). The capital and operating costs for each respective technology are modeled. We also compare results using two different resource data sources.

15 GEOTHERMAL ENERGY↗
DOE OSTI2024

Pilgrim Hot Springs: GEOPHIRES Inputs and Outputs for Direct-Use Geothermal District Heating and Cooling

This dataset includes files for a techno-economic analysis conducted using the GEOPHIRES simulator to examine the feasibility of expanding a larger district heating site in a remote location: Pilgrim Hot Springs, Alaska. Files included here are GEOPHIRES inputs and outputs for five different scenarios with varying demand, cycle, and system design characteristics to analyze. Also included is the link to the GEOPHIRES GitHub, as well as a link to the dataset that contains the energy modelling used to determine the heating demand for the district. For a list of the differences between scenarios, see the included "Input Overview.txt" file. Fields included in the input files are: subsurface technical parameters, surface technical parameters, financial parameters, capital and O&M parameters, as well as simulation parameters. The output files are case reports that summarize all equipment, reservoir characteristics, costs, and heating profiles.

15 GEOTHERMAL ENERGY↗
DOE OSTI2018

Triton: Survivability Enhancement of a Multi-Mode Point Absorber

This submission includes final project deliverables for DE-FOA-0001310. The overall goal of the project was to design and validate a survival mode for the Triton WEC that allows for a reduction in peak loads, while simultaneously allowing for a reduction of capital cost due to the elimination of overdesign to account for uncertainty. In addition, the project sought to carefully understand performance of the design without survival mode engaged under extreme wave conditions so as to better understand how system loads vary and hence determine conditions where survival mode needs to be engaged, thereby allowing for an optimum balance between maximum power capture and acceptable risk within the capabilities of the design.

16 TIDAL AND WAVE POWER↗
DOE OSTI2010

H2A Biomethane Model Documentation and a Case Study for Biogas From Dairy Farms

The new H2A Biomethane model was developed to estimate the levelized cost of biomethane by using the framework of the vetted original H2A models for hydrogen production and delivery. For biomethane production, biogas from sources such as dairy farms and landfills is upgraded by a cleanup process. The model also estimates the cost to compress and transport the product gas via the pipeline toexport it to the natural gas grid or any other potential end-use site. Inputs include feed biogas composition and cost, required biomethane quality, cleanup equipment capital and operations and maintenance costs, process electricity usage and costs, and pipeline delivery specifications.

09 BIOMASS FUELS↗
DOE OSTI2011

CNCC Craig Campus Geothermal Project: 82-well closed loop GHP well field to provide geothermal energy as a common utilitiy for a new community college campus

Colorado Northwestern Community College (CNCC) is working collaboratively with recipient vendor Chevron Energy Solutions, an energy services company (ESCO), to develop an innovative GHP project at the new CNCC Campus constructed in 2010/2011 in Craig, Colorado. The purpose of the CNCC Craig Campus Geothermal Program scope was to utilize an energy performance contracting approach to develop a geothermal system with a shared closed-loop field providing geothermal energy to each building's GHP mechanical system. Additional benefits to the project include promoting good jobs and clean energy while reducing operating costs for the college. The project has demonstrated that GHP technology is viable for new construction using the energy performance contracting model. The project also enabled the project team to evaluate several options to give the College a best value proposition for not only the initial design and construction costs but build high performance facilities that will save the College for many years to come. The design involved comparing the economic feasibility of GHP by comparing its cost to that of traditional HVAC systems via energy model, financial life cycle cost analysis of energy savings and capital cost, and finally by evaluating the compatibility of the mechanical design for GHP compared to traditional HVAC design. The project shows that GHP system design can be incorporated into the design of new commercial buildings if the design teams, architect, contractor, and owner coordinate carefully during the early phases of design. The public also benefits because the new CNCC campus is a center of education for the much of Northwestern Colorado, and students in K-12 programs (Science Spree 2010) through the CNCC two-year degree programs are already integrating geothermal and GHP technology. One of the greatest challenges met during this program was coordination of multiple engineering and development stakeholders. The leadership of Principle Investigator Pres. John Boyd of CNCC met this challenge by showing clear leadership in setting common goals and resolving conflicts early in the program.

15 GEOTHERMAL ENERGY↗
DOE OSTI2011

Methodology for Scaling Fusion Power Plant Availability

Normally in the U.S. fusion power plant conceptual design studies, the development of the plant availability and the plant capital and operating costs makes the implicit assumption that the plant is a 10th of a kind fusion power plant. This is in keeping with the DOE guidelines published in the 1970s, the PNL report1, "Fusion Reactor Design Studies - Standard Accounts for Cost Estimates. This assumption specifically defines the level of the industry and technology maturity and eliminates the need to define the necessary research and development efforts and costs to construct a one of a kind or the first of a kind power plant. It also assumes all the "teething" problems have been solved and the plant can operate in the manner intended. The plant availability analysis assumes all maintenance actions have been refined and optimized by the operation of the prior nine or so plants. The actions are defined to be as quick and efficient as possible. This study will present a methodology to enable estimation of the availability of the one of a kind (one OAK) plant or first of a kind (1st OAK) plant. To clarify, one of the OAK facilities might be the pilot plant or the demo plant that is prototypical of the next generation power plant, but it is not a full-scale fusion power plant with all fully validated "mature" subsystems. The first OAK facility is truly the first commercial plant of a common design that represents the next generation plant design. However, its subsystems, maintenance equipment and procedures will continue to be refined to achieve the goals for the 10th OAK power plant.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗
DOE OSTI2011

Impact of Large Scale Energy Efficiency Programs On Consumer Tariffs and Utility Finances in India

Large-scale EE programs would modestly increase tariffs but reduce consumers' electricity bills significantly. However, the primary benefit of EE programs is a significant reduction in power shortages, which might make these programs politically acceptable even if tariffs increase. To increase political support, utilities could pursue programs that would result in minimal tariff increases. This can be achieved in four ways: (a) focus only on low-cost programs (such as replacing electric water heaters with gas water heaters); (b) sell power conserved through the EE program to the market at a price higher than the cost of peak power purchase; (c) focus on programs where a partial utility subsidy of incremental capital cost might work and (d) increase the number of participant consumers by offering a basket of EE programs to fit all consumer subcategories and tariff tiers. Large scale EE programs can result in consistently negative cash flows and significantly erode the utility's overall profitability. In case the utility is facing shortages, the cash flow is very sensitive to the marginal tariff of the unmet demand. This will have an important bearing on the choice of EE programs in Indian states where low-paying rural and agricultural consumers form the majority of the unmet demand. These findings clearly call for a flexible, sustainable solution to the cash-flow management issue. One option is to include a mechanism like FAC in the utility incentive mechanism. Another sustainable solution might be to have the net program cost and revenue loss built into utility's revenue requirement and thus into consumer tariffs up front. However, the latter approach requires institutionalization of EE as a resource. The utility incentive mechanisms would be able to address the utility disincentive of forgone long-run return but have a minor impact on consumer benefits. Fundamentally, providing incentives for EE programs to make them comparable to supply-side investments is a way of moving the electricity sector toward a model focused on providing energy services rather than providing electricity.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2011

Water recovery using waste heat from coal fired power plants.

The potential to treat non-traditional water sources using power plant waste heat in conjunction with membrane distillation is assessed. Researchers and power plant designers continue to search for ways to use that waste heat from Rankine cycle power plants to recover water thereby reducing water net water consumption. Unfortunately, waste heat from a power plant is of poor quality. Membrane distillation (MD) systems may be a technology that can use the low temperature waste heat (<100 F) to treat water. By their nature, they operate at low temperature and usually low pressure. This study investigates the use of MD to recover water from typical power plants. It looks at recovery from three heat producing locations (boiler blow down, steam diverted from bleed streams, and the cooling water system) within a power plant, providing process sketches, heat and material balances and equipment sizing for recovery schemes using MD for each of these locations. It also provides insight into life cycle cost tradeoffs between power production and incremental capital costs.

01 COAL, LIGNITE, AND PEAT↗