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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 109 records · Page 6
All sourcesNASA NTRSDOE OSTI
DOE OSTI2016

Wholesale Electricity Market Design with Increasing Levels of Renewable Generation: Incentivizing Flexibility in System Operations

This paper discusses the importance and challenges of incentivizing flexibility during short-term operations of the bulk power system due to the increasing variability and uncertainty from growing penetrations of variable generation (VG). Operational flexibility can refer to many aspects of a resource's capability to support the power system, such as the speed, range, and duration of power output, as well as the ability to autonomously respond to frequency or voltage changes. Inefficient utilization of existing flexibility, or unwillingness of resources to provide flexibility, can compromise system reliability by not meeting the changing net load, and it can also lead to higher costs when an inefficient use of flexibility resources occurs. There are many existing characteristics of market design that incentivize flexibility in some manner. How they incentivize the provision of flexibility as well as the level of flexibility is still debated. We explore some of these existing market designs, as well as new market mechanisms, such as pay-for-performance regulating reserve and flexible ramping products, that aim to explicitly incentivize the provision of more flexibility to the system, particularly as a result of increasing VG penetration levels.

24 POWER TRANSMISSION AND DISTRIBUTION↗
DOE OSTI2016

Tunable Oleo-Furan Surfactants by Acylation of Renewable Furans

An important advance in fluid surface control was the amphiphilic surfactant comprised of coupled molecular structures (i.e. hydrophilic and hydrophobic) to reduce surface tension between two distinct fluid phases. However, implementation of simple surfactants has been hindered by the broad range of applications in water containing alkaline earth metals (i.e. hard water), which disrupt surfactant function and require extensive use of undesirable and expensive chelating additives. Here we show that sugar-derived furans can be linked with triglyceride-derived fatty acid chains via Friedel-Crafts acylation within single layer (SPP) zeolite catalysts. These alkylfuran surfactants independently suppress the effects of hard water while simultaneously permitting broad tunability of size, structure, and function, which can be optimized for superior capability for forming micelles and solubilizing in water.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2016

Implications of Zero-Carbon Nuclear Renewable Economy: Equity, Economics, and Social Costs

Different energy systems have different impacts on equity, economics, and social costs of energy. This leads to alternative strategies for a zero-carbon economy from considering all options to a renewables-only strategy. We examine implications of different choices from a long-term perspective. This is coupled to but separate from the discussion of how to transition to a low-carbon energy system. If we are to stop greenhouse gas emissions with current goals, the transition must be fast. That requires a large nuclear contribution. Experiences in France and Sweden indicate that one can transition the electric grid from fossil fuels to nuclear in 20 to 25 years if it is a priority. Neither renewables with associated storage and transmission nor carbon capture and sequestration for fossil fuel use in electricity generation are available today at competitive costs to do that. The cost of energy has historically been a major factor in determining where industry and cities are built because it is a large fraction of the global economy. The development of low-cost methods to transport coal, oil, and natural gas partly broke that connection by enabling relatively uniform global energy costs. Nuclear energy because of the low-cost of fuel transport has the same characteristic. Renewables are location dependent. In a renewables-only future, the renewable resources distribution determines local energy costs that directly impacts where there is future economic growth and where there will be lower costs of living. In the U.S. today solar is generally uneconomic. Some Great Plains wind is competitive. Offshore wind is uneconomic. Based on projections of renewables costs, an all-renewable U.S. would see (1) movement of industry and people to between the Mississippi River (water and transportation) and the high plains (high wind velocities and low construction costs) and the southwest and (2) growing regional differences in standards of living. The costs of moving energy from renewables long distances is partly because of the high cost of transport systems (high-voltage lines with low capacity factors, hydrogen inter-conversion losses, etc.) and partly because of the non-dispatchability of renewables. A nuclear renewable world will have large variations in the relative amounts of nuclear, wind and solar with location-reflecting local cost of renewable resources. The deployment of wind and solar would be similar to hydro and geothermal-deployed where there is a concentrated resource. In the U.S. and globally this will likely be the norm because countries with limited access to low-cost renewables will not accept lower standards of living. The relative quantities of nuclear, wind and solar will change with relative advances in energy technologies. Energy is a large fraction of the economy; thus, energy choices have major economic, equity, and social implications. That, in turn, impacts standards of living and economic competitiveness. (authors)

29 ENERGY PLANNING, POLICY, AND ECONOMY↗