Wind and solar, while growing fast, still have intermittency issues.
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Improved electricity storage is one answer to the intermittency problem.
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The Venezuelan catastrophe is an extreme, worst case scenario of intermittency.
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Cost is no longer a major barrier for renewables; intermittency is.
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And no one has yet solved the renewable energy intermittency problem — i.e.
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Space-based solar would not only offer a solution to intermittency, but also delivery.
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Such a combination of intermittency and lack of resource visibility could seriously undermine reliability.
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"The one thing we don't have solutions for are intermittency and variability," Reed says.
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Once it hits 70 to 80% and beyond, the intermittency issues become more pronounced.
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The weakness of energy systems powered by the sun and the wind is their intermittency.
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Extensive use of wind and solar energy requires large-scale energy storage to handle their intermittency.
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The intermittency is predictable, which from a grid perspective makes tidal energy much easier to integrate.
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As everywhere, intermittency is a problem because the sun does not always shine or the wind blow.
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If renewables can meaningfully solve their reliability and intermittency issues, then coal's raison d'être may well evaporate.
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Such intermittency has been seen in Martian methane results before and it has yet to be accounted for.
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They also represent a sustainable way to deal with the intermittency of renewable energy from solar and wind.
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But they generate a meagre 7.7% of output because of intermittency, compared with 75% for coal (see chart 3).
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In contrast, renewables have faced the 'intermittency' challenge—the sun doesn't always shine, and the wind doesn't always blow.
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"I think this has been a really good example of how the grid deals with solar intermittency," Osha said.
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The other two are inherent to the nature of wind and solar: their intermittency and their very low running costs.
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This intermittency — which is also inherent in solar power — is what dooms efforts to mandate increased use of renewable energy.
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This is the holy grail of renewable energy because it would solve the intermittency problem of wind and solar power.
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The transition to renewables needs to take account of serious considerations, like overcoming intermittency, providing energy security and balancing economic realities.
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A fledgling energy storage industry and body of research has emerged to try to find a solution to the intermittency problem.
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Duke cites the lack of storage technology and the intermittency of solar and wind as reasons they can't reach that level.
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Upgrades to the electricity grid and management systems are paving the way for greater solar diffusion by accommodating solar's inherent intermittency.
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And he noted that the increased use of renewables can cause intermittency issues when solar and wind power isn't as strong.
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Paradoxically, that means the more states support renewables, the more they pay for conventional power plants, too, using "capacity payments" to alleviate intermittency.
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American and German engineers could work together on problems of energy intermittency from solar and wind, and smart grid, making renewables economically affordable.
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This illustrates the key challenge that wind and solar (together known as variable renewable energy, or VRE) pose to self-contained grids: their intermittency.
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Three more or less plausible alternatives to batteries could finesse the intermittency and seasonality of solar and wind and help generate carbon-neutral energy.
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With over half of its installed capacity coming from hydropower and geothermal energy, it is already in a good position to deal with intermittency problems.
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Despite tens of billions in subsidies, wind and solar power still generate just 7 percent of the nation's electricity and are both plagued by intermittency.
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Intermittency issues refer to the availability of renewable power on days when there isn't enough resources such as sunlight or wind to power such plants.
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And, given the intermittency issues and cost overruns associated with solar and wind projects, embracing the "Tesla Model" will only hasten the power authority's destruction.
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When clouds roll in blocking the sun for a short time (intermittency), you need a grid that can use traditional sources to pick up the slack.
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But he thinks it would be better for utilities to deploy them to regulate the intermittency of electricity supply in substations, rather than putting them in homes.
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Other solutions to intermittency include more long-distance power transmission capacity, more grid-scale electricity storage, and more flexibility in both supply and demand from capacity markets.
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Now, there are still some issues special to renewables, in particular problems of intermittency: consumers may want power when the wind doesn't blow and the sun doesn't shine.
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Today, utilities manage the intermittency and seasonality of renewable energy by firing up small "peaker" power plants, typically fueled by natural gas, when prices and demand are high.
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True, there are issues of intermittency remaining — the wind doesn't always blow, the sun doesn't always shine — although batteries and other energy storage technologies are also making rapid progress.
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The first is the growth in renewable energy, which creates intermittency in supply as well as occasional supply spikes that lead to curtailment (shutting wind and solar off temporarily).
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But Mr Galán is sceptical that batteries can last long enough to handle intermittency, or that customers will care enough about distributed energy to make the domestic-battery business compelling.
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Baseload coal power is not good at offsetting the intermittency of sun and wind; India would do better to opt for hydroelectric storage and quick-response natural-gas plants instead.
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When there is a shortfall in electricity, they are currently the only viable and widespread method for managing the intermittency of renewable energy, which we so desperately need to proliferate.
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Second, we could generate base-load electricity with nuclear fission, the carbon-free energy technology we already possess, producing enough energy to ignore the intermittency and seasonality of solar and wind.
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You mentioned the investment needed to expand solar grids and for measures to mitigate the intermittency of solar power; these could easily add 50% to the prices quoted in recent bids.
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Unlike solar or wind energy, green gas suffers from no intermittency problems, can be produced 24 hours a day, and easily stored, providing a useful complement for any renewable energy mix.
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What they're saying: "Not only are [renewables] causing intermittency issues, they can no longer recover costs in the power market," said Robert Whaley, principal analyst of power and renewables at Wood Mackenzie.
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It also means that renewables may come to compete more directly with natural gas in some markets, rather than requiring more gas to balance their intermittency, as has been the case so far.
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But others reject that because of the intermittency problem, arguing that in the 2030s and beyond, society will need new huge power plants that can run most of the time without generating greenhouse emissions.
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This investment will have to include long range, high-voltage electrical transmission, to take care of the intermittency problem of solar and wind power — and the introduction of efficient, high-speed electrified rail travel.
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"(Renewables) intermittency means the frequency on the grid changes more quickly than before so we need faster technology which can react to that," said Cathy McClay, commercial head at the British National Grid system operator.
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Other countries around the North Sea have woken up to this problem, usually focusing on various technologies for converting "power to gas" as a way of ensuring this intermittency can be managed at enormous scale.
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The issues mentioned herein — bidirectional flow, intermittency, visibility and communication — are not insurmountable, and demonstrate exactly why utilities, based on the needs of their respective systems, should be planning for and making appropriate investment decisions now.
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I believe it's in combination with natural gas, the intermittency, when winds aren't blowing and the sun isn't shining, combining it with natural gas has got to be part of the answer of answering the power.
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Grid managers have been grappling with this problem of increasing intermittency for almost a decade as wind and solar farms provide an increasing share of generation on the grid (and behind-the-meter at customers' own premises).
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The holy grail of renewable electricity is batteries cheap and capacious enough to overcome the intermittency of solar and wind power—for example, to store enough power from solar panels to keep the lights on all night.
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The expected growth in renewable energy will come even though such energy is "less cost competitive in the region compared to the rest of the world, and (faces) challenges such as land acquisition and intermittency issues," Tao added.
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"It also holds promise as a complement to renewables, resolving the intermittency issue of wind and solar power, as they take on a larger share in the electricity market, which in turn is expected to grow exponentially," she said.
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The other side: To be sure, gas still has a role to play, not only in replacing remaining coal generation, but also in supporting the intermittency of renewables — a growing challenge as the penetration of solar and wind increases.
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Yet the report stops short of making the most obvious recommendations to address this challenge—eliminating the subsidies and forcing renewable energy generators to pay for the costs they impose on the grid because of their intermittency and unreliability.
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Developers and project lenders said they need to consider grid congestion, which can curtail power that gets to the network from any one plant; intermittency of wind and solar power, which affects current flow; and transmission losses, called marginal loss factors (MLFs).
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Storing excess energy generated by the Hornsdale Wind Farm, the Powerpack 2 will enable the utility to "firm up renewable generation by reconciling the intermittency of power from these sources and storing excess capacity to dispatch when it's needed," according to Tesla.
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Are batteries now cheap enough to be a cost-effective way of solving energy crises like that in southern Australia, brought on since July by storms, heatwaves, the intermittency of solar and wind power and the closure of coal- and gas-fired power stations?
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The inherent challenges of deploying new technologies and resources — reliability, bidirectional flow, intermittency, visibility, and communication, to name a few — are not insurmountable and demonstrate exactly why federal and state authorities and electricity sector stakeholders should be planning for and making appropriate investment decisions now.
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Research has shown that deploying renewable energy over a vast area connected by a transmission system would actually increase reliability and reduce intermittency compared to smaller networks since it would route power from areas where there is sunlight and wind to areas where there isn't.
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This could alleviate the intermittency problem of wind and solar (the wind doesn't always blow and the sun doesn't always shine) through 'load balancing': while EVs are connected to the grid, they would store excess electricity during low demand periods, and release them as demand rises.
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While renewables are often assumed to be the great green hope for a low-carbon future and while they should be part of the way forward, the inherent intermittency and storage limitations will not allow them to stand up against carbon emissions at the global scale.
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But renewables are intermittent, which means that in systems where the infrastructure was designed before intermittency became an issue—almost all of them, in practice—fossil-fuel, hydroelectric and nuclear plants are needed more or less as much as ever at times when the sun doesn't shine and the winds don't blow.
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One of the issues with renewable-energy projects like solar and wind power plants are their intermittency — that refers to the fact that the sun isn't shining and the wind is not blowing 24-hours a day, limiting the periods of time during which these projects can be a source of power generation.
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Renewable wind or solar make good domestic power sources, but they still face the issue of intermittency, and are not yet ready to sufficiently support industry and large-scale economic growth What's next: Developing giants such as China and India but also countries such as Turkey and Poland continue to bank on coal.
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A better route would be to phase away from the early 20th-century centralized power model and redesign the power grid to make it more resilient by maximizing the use of solar and offshore wind energy resources and by supplementing the centralized power system with dynamic distribution systems that deal with the intermittency of renewable energy sources.
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So we still have quite a ways to go, particularly when you're trying to get from 20 percent of the energy sources up to the eventual 100 percent we need, where then you run into the big challenge of intermittency [dips and peaks in power as wind and solar sources vary] and the cost of adding storage that would deal with that.
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In particular, renewable energy — wind and solar — has become much cheaper in recent years, and progress in energy storage looks increasingly likely to resolve the problem of intermittency (The sun doesn't always shine, the wind doesn't always blow.) Or to put it a different way, we face a clear and present danger, but we have the means and the knowledge to deal with that danger.
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A colleague of Kenneth Craik, Margaret Vince, related the concept of intermittency to the Psychological refractory periodM.A. Vince. "The intermittency of control movements and the psychological refractory period". British Journal of Psychology, 38:149–157, 1948.
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The measure LAM has maxima at chaos-chaos transitions (laminar phases, intermittency).
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Duffing oscillator. This is an example of crisis-induced intermittency. Lorenz attractor showing intermittency. The system spends long periods close to the bright periodic orbit, occasionally moving away for phases of chaotic dynamics that cover the rest of the attractor.
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This is an example of Pomeau–Manneville dynamics. In dynamical systems, intermittency is the irregular alternation of phases of apparently periodic and chaotic dynamics (Pomeau–Manneville dynamics), or different forms of chaotic dynamics (crisis- induced intermittency). Pomeau and Manneville described three routes to intermittency where a nearly periodic system shows irregularly spaced bursts of chaos. Yves Pomeau and Paul Manneville, Intermittent Transition to Turbulence in Dissipative Dynamical Systems, Commun. Math. Phys. vol.
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DC-to-DC converters are subject to different types of chaotic dynamics such as bifurcation, crisis, and intermittency.
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Bertelson, P. (1966). Central intermittency twenty years later. The Quarterly Journal of Experimental Psychology, 18, 153-163. Bertelson, P., & Tisseyre.
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Many small-scale deployments of rooftop photovoltaic panels tend to multiply the effect of the intermittency of solar generation – creating a problem for grid operators. [REF] UltraBattery energy storage has been used to reduce renewable intermittency by ramping the power on the electricity grid in a controlled manner, making renewable-generated power more predictable.
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In the theory of dynamical systems (or turbulent flow), the Pomeau–Manneville scenario is the transition to chaos (turbulence) due to intermittency.
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In 1990 Gärtner and Molchanov wrote a seminal paper on intermittency in the parabolic Anderson model; the paper introduced a new approach to intermittency via the study of Lyapunov coefficients. Gärtner was a member from 1984 to 1992 of the editorial board of Probability Theory and Related Fields and from 1990 to 2000 of the editorial board of Mathematische Nachrichten. In 1992 Gärtner was an invited lecturer at the first European Congress of Mathematics in Paris. In 1994 he was an invited speaker with talk Parabolic Systems in Random Media and Aspects of Intermittency at the International Congress of Mathematicians in Zurich.
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There are at least three areas where intermittent control is relevant. Firstly, continuous-time model-based predictive control where the intermittency is associated with on- line optimisation. Secondly, event-driven control systems where the intersample interval is time varying and determined by the event times. Thirdly, explanation of physiological control systems which, in some cases, have an intermittent character. This intermittency may be due to the “computation” in the central nervous system.
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A. A. Migdal, "Loop Equation and Area Law in Turbulence", 'arXiv, October 1993A. A. Migdal, "Turbulence as Statistics of Vortex Cells", arXiv, June 1993 He initiated (with V. Gurarie, G. Falkovich, and V. Lebedev) a description of intermittency in nonlinear systems by means of Instanton solutions of the stochastic differential equations.G. Falkovich, I. Kolokolov, V. Lebedev, and A. Migdal "Instantons and Intermittency", Physical Review E, November 1996 As of 2020, he is a research scientist at the New York University.
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The average power grid derived slightly more than 60% of its energy from fossil fuels in 2019. A pie chart is shown in the film with total battery storage compared to yearly energy use, which is a factor of thousand higher. The filmmakers suggest that this amount of energy storage is needed to make sure intermittency of renewables does not lead to power outages. In reality, battery storage is only part of solving intermittency, and using a mix of different energy sources reduces the need for batteries.
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Since the time spent near the periodic orbit depends sensitively on how closely the system entered its vicinity (in turn determined by what happened during the chaotic period) the length of each phase is unpredictable. Another kind, on- off intermittency, occurs when a previously transversally stable chaotic attractor with dimension less than the embedding space begins to lose stability. Near unstable orbits within the attractor orbits can escape into the surrounding space, producing a temporary burst before returning to the attractor. E.Ott and J.C. Sommerer, Blowout bifurcations: the occurrence of riddled basins and on-off intermittency, Physics Letters A, vol.
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Gamma-Re (γ-Re) transition model is a two equation model used in Computational Fluid Dynamics (CFD) to modify turbulent transport equations to simulate laminar, laminar-to-turbulent and turbulence states in a fluid flow. The Gamma-Re model does not intend to model the physics of the problem but attempts to fit a wide range of experiments and transition methods into its formulation. The transition model calculated an intermittency factor that creates (or extinguishes) turbulence by slowly introducing turbulent production at the laminar-to-turbulent transition location. Intermittency Value on a Turbomachinery blade; R.B. Langtry.
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Colloid cysts represent 0.5–1.0% of intracranial tumors. Symptoms can include headache, vertigo, memory deficits, diplopia, behavioral disturbances, and in extreme cases, sudden death. Intermittency of symptoms is characteristic of this lesion. Untreated pressure caused by these cysts can result in brain herniation.
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Fluids 18, 075104. Y. Li & C. Meneveau, “Intermittency trends and Lagrangian evolution of non-gaussian statistics in turbulent flow and scalar transport” (2006), J. Fluid Mech., 558, 133-142. Y. Li & C. Meneveau, “Origin of non-Gaussian statistics in hydrodynamic turbulence” (2005), Phys. Rev. Lett.
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As of 2011, however, intermittent supply was common in at least parts of Dhaka, forcing families to purchase drinking water and use pond or river water for their other needs. Regular power cuts, which turn off well pumps, also contribute to the intermittency of supply.
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Each dye is photobleached to return the field to a dark state, so the next dye can bind and be observed. The advantage of this method, compared to other stochastic methods, is that in addition to obtaining the super-resolved image of the fixed target, it can measure the dynamic binding kinetics of the diffusing probe molecules, in solution, to the target. Combining 3D super-resolution technique (e.g. the double-helix point spread function develop in Moerner's group), photo-activated dyes, power- dependent active intermittency, and points accumulation for imaging in nanoscale topography, SPRAIPAINT (SPRAI=Super resolution by PoweR-dependent Active Intermittency) can super-resolve live-cell walls.
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Andrew William Gibson (born 1949) is a scholar, philosopher, children's writer and academic. He has published widely on James Joyce, Samuel Beckett, literary theory and philosophy - particularly the work of Alain Badiou. His publications include Joyce's Revenge: History, Politics and Aesthetics in James Joyce's 'Ulysses' (Oxford University Press, 2002), Beckett and Badiou: The Pathos of Intermittency (Oxford University Press, 2006), Intermittency: The Concept of Historical Reason in Recent French Philosophy (Edinburgh University Press, 2011), and The Strong Spirit: History, Politics and Aesthetics in the writings of James Joyce 1898-1915 (Oxford University Press, 2013). His most recent book is Misanthropy: The Critique of Humanity (Bloomsbury, 2017).
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In order to protect against intermittency issues and system failures, many off-grid communities create hybrid energy systems. These combine traditional renewables like solar PV, and wind, with more constant sources of power like micro-hydro or even diesel generators. Tfective than extending grids to isolated communities.
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When renewables produce energy that is not currently needed, the electrical energy is usually directed to charge a battery. This solves intermittency issues caused by the non-constant production of renewables and allows for variations in building loads. Common batteries include the lead- acid battery and lithium-ion battery.
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As of 2019, only 17% of electricity in the U.S. is generated from renewable energy, of which, 7% is from hydroelectric dams, 6% from wind turbines, and 1% solar panels. The intermittency of wind and solar power poses the issue of storage, and there are no rivers for new dams.
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Moreover, at small specimen sizes the yield stress is not well defined by the 0.2% plastic strain criterion anymore, since this value varies specimen by specimen. Similar intermittent effects has been studied in many completely different systems, including intermittency of energy dissipation in magnetism (Barkhausen effect), superconductivity, earthquakes, and friction.
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Quantum confinement effects in quantum dots can also result in fluorescence intermittency, called "blinking." CdSe quantum dots have been implemented in a wide range of applications including solar cells, light emitting diodes, and biofluorescent tagging. CdSe-based materials also have potential uses in biomedical imaging. Human tissue is permeable to near infra-red light.
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Blinking colloidal nanocrystals is a phenomenon observed during studies of single colloidal nanocrystals that show that they randomly turn their photoluminescence on and off even under continuous light illumination. This has also been described as luminescence intermittency. Similar behavior has been observed in crystals made of other materials. For example, porous silicon also exhibits this affect.
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The highest intermittency has been measured in the small Luapula Utility with 6 hours per day. The only utility providing continuous supply in 2007 was in Chipata, while in 2010 the only utility that provided near continuous supply was the Northwestern Water and Sewerage Company. Wastewater treatment. Wastewater treatment plants regularly do not achieve effluent standards.
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The \zeta(q) are statistically interpreted, as they characterize the evolution of the distributions of the T_X(a) as a goes from larger to smaller scales. This evolution is often called statistical intermittency and betrays a departure from Gaussian models. Modelling as a multiplicative cascade also leads to estimation of multifractal properties. This methods works reasonably well, even for relatively small datasets.
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In highly turbulent flows, intermittency is seen in the irregular dissipation of kinetic energy C. Meneveau and K.R. Sreenivasan, The multifractal nature of turbulent energy dissipation, Journal of Fluid Mechanics, vol. 224, 1991, pp. 429-484 and the anomalous scaling of velocity increments.F. Anselmet, Y. Gagne, E.J. Hopfinger, R.A. Antonia, High-order velocity structure functions in turbulent shear flows, Journal of Fluid Mechanics, vol.
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Voice disorders range from aphonia (loss of phonation) to dysphonia, which may be phonatory and/or resonance disorders. Phonatory characteristics could include breathiness, hoarseness, harshness, intermittency, pitch, etc. Resonance characteristics refer to overuse or underuse of the resonance chambers resulting in hypernasality or hyponasality. Several examples of voice problems are vocal cord nodules or polyps, vocal cord paralysis, paradoxical vocal fold movement, and spasmodic dysphonia.
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The instantaneously space and phase correlated vorticity found within the coherent structure expressions can be defined as coherent vorticity, hence making coherent vorticity the main characteristic identifier for coherent structures. Another characteristic inherent in turbulent flows is their intermittency, but intermittency is a very poor identifier of the boundaries of a coherent structure, hence it is generally accepted that the best way to characterize the boundary of a structure is by identifying and defining the boundary of the coherent vorticity. By defining and identifying coherent structure in this manner, turbulent flows can be decomposed into coherent structures and incoherent structures depending on their coherence, particularly their correlations with their vorticity. Hence, similarly organized events in an ensemble average of organized events can be defined as a coherent structure, and whatever events not identified as similar or phase and space aligned in the ensemble average is an incoherent turbulent structure.
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336 he showed that in a dense fluid the interactions are different from what they are at equilibrium and propagate through hydrodynamic modes, which leads to the divergence of transport coefficients in 2 spatial dimensions. This aroused his interest in fluid mechanics, and in the transition to turbulence. Together with Paul Manneville they discovered a new mode of transition to turbulenceManneville, P. and Pomeau Y., « Intermittency and the Lorentz model », Physics Letters A, 1979. 75 (1-2), pp.
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Bladder outlet obstruction (BOO) can be caused by BPH. Symptoms are abdominal pain, a continuous feeling of a full bladder, frequent urination, acute urinary retention (inability to urinate), pain during urination (dysuria), problems starting urination (urinary hesitancy), slow urine flow, starting and stopping (urinary intermittency), and nocturia. BPH can be a progressive disease, especially if left untreated. Incomplete voiding results in residual urine or urinary stasis, which can lead to an increased risk of urinary tract infection.
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Nonetheless, for the first time in more than ten years, electricity prices for household customers fell at the beginning of 2015. Tariff rates for PV electricity vary depending on system size and location. In 2009, tariffs were raised for electricity immediately consumed rather than supplied to the grid with increasing returns if more than 30% of overall production is consumed on-site. This is to incentivise demand- side management and help develop solutions to the intermittency of solar power.
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188, 1994, pp. 39–47 In crisis-induced intermittency a chaotic attractor suffers a crisis, where two or more attractors cross the boundaries of each other's basin of attraction. As an orbit moves through the first attractor it can cross over the boundary and become attracted to the second attractor, where it will stay until its dynamics moves it across the boundary again. Intermittent behaviour is commonly observed in fluid flows that are turbulent or near the transition to turbulence.
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Dinorwig could store cheap energy produced at night by low marginal cost plant and then generate during times of peak demand, so displacing low efficiency plant during peak demand periods. There were plans for a pumped storage facility near Exmoor but it was not built. With the increase of renewables such as wind and solar power, the need for storage is expected to increase to deal with intermittency."Understanding the Balancing Challenge" Imperial College London, August 2012. Retrieved: 22 January 2015.
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UltraBattery can also be used for demand management, which addresses the problems of grid supply and demand, but not necessarily those related to renewable intermittency. At the periphery of large grids, or on old grid infrastructure – such as single-wire earth return networks – the effect of a demand spike or variance in supply can be amplified because of its scale relative to other local activity. UltraBattery can reduce these effects and ensure power quality from the grid for local users.
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As the Reynolds number increases, the continuous turbulent-flow moves closer to the inlet and the intermittency in between increases, until the flow becomes fully turbulent at > 2900. This result is generalized to non-circular channels using the hydraulic diameter, allowing a transition Reynolds number to be calculated for other shapes of channel. These transition Reynolds numbers are also called critical Reynolds numbers, and were studied by Osborne Reynolds around 1895. The critical Reynolds number is different for every geometry.
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For example, the flywheel mechanism used to smooth out the delivery of power from a driving device to a driven machine, was invented by ibn Bassal (fl. 1038–1075) of al- Andalus, who pioneered the use of the flywheel in the noria and saqiyah.Ahmad Y. al-Hassan, Flywheel Effect for a Saqiya. In 1206, Ismail al-Jazari introduced the use of the crankshaft in the noria and saqiya, and the concept of minimizing intermittency was implied for the purpose of maximising their efficiency.
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In both cases the fluorophores are driven between an active-ON and an inactive-OFF state by light. In PALM, however, photoactivation and photobleaching confine the life of the fluorophore to a limited interval of time, and a continuous emission of the fluorophore is desirable in between without any fluorescence intermittency. In STORM stochastic photoblinking of the organic fluorophores (typically brighter than fluorescent proteins) was originally exploited to separate neighboring dyes. In this respect, the more robust the blinking, the higher the probability of distinguishing two neighbouring fluorophores.
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He also characterized the role of non-adiabatic damping of adsorbate vibrations and the spin-splitting of surface bands by the Rashba (spin-orbit) effect. More recently he has probed the microscopic- macroscopic connection, developing tools to study microscopic magnetic fluctuations using coherent soft x-ray beams. His current emphasis is to probe, on the scale of a few domains, intermittent dynamics and memory effects in field- and thermally driven magnetization reversal. Understanding the impact of newly discovered hidden symmetries on these cascades is important to understanding microscopic intermittency in a much broader context.
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Chalcidice has been occupied since the Palaeolithic, the beginning of human culture, which started at about 3.3 MYA (million years ago). Whether it was continuous occupation for that length of time is not answered by the evidence, which is intermittent. Whether the intermittency belongs to the evidence or to the habitation is not yet known. The major find site for the Palaeolithic is Petralona Cave, where the Petralona Skull was found, from a fully human Hominid believed to be ancestral (or close to it) to both modern and Neanderthal men.
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Armed with Science. U.S. Department of Defense Some analysts argue that conventional renewable energy sources, wind and solar do not offer the scalability necessary for a large-scale decarbonization of the electric grid, mainly due to intermittency-related considerations.Running on renewables: How sure can we be about the future? Clara Heuberger et al, Real- World Challenges with a Rapid Transition to 100% Renewable Power Systems Joule (2018). DOI: 10.1016/j.joule.2018.02.002 Along with other commentators who have questioned the links between the anti-nuclear movement and the fossil fuel industry.
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His research deals with geometrical approaches to Markov processes (Martin boundaries and diffusion on Riemannian manifolds) and with spectral theory (localization in random media and spectral properties of Riemannian manifolds). His research on applied mathematics includes physical processes and fields in disordered structures involving averaging and intermittency with applications to geophysics, astrophysics, oceanography. With regard to physical processes, he has done research on wave processes in periodic and random media, quantum graphs, and applications to optics. With Ilya Goldsheid and Leonid Pastur he proved in 1977 localization in the Anderson model in one dimension.
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One of the river's peculiarities is its annual intermittency: it usually dries in the middle of October to reappear in the second half of March; therefore it has been given the nickname ("River of the two Madonnas"), alluding to the festivities of Annunciation (March 25) and Madonna del Rosario (October 7). This phenomenon could imply that the river is the vent of an unexplored underground cavity in the Grigna, which gets periodically filled. The river is mentioned by the name in Leonardo da Vinci's Atlantic Codex: Other authors who wrote about the river include Pliny the Elder and Lazzaro Spallanzani.
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A wind farm field trial in Hampton, New South Wales (Australia), is testing a system designed to demonstrate the use of energy storage to address the short-term intermittency of wind generation. The trial compared the performance of the UltraBattery and three other lead-acid battery types for renewable energy smoothing applications. Measurements of the variations in cell voltage in each string of 60 cells connected in series showed that the UltraBattery had far less variation over a 10-month period (a 32% increase in standard deviation of voltage range variation, compared to 140%–251% for the other three battery types).
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Hug emphasizes the need to switch to renewable energy sources to keep the world a hospitable place. She works on exploring ways to address the variability and intermittency of renewable energy generation such that one day we can use various sources of sustainable energy to reliably power the grid. To do this, Hug and her team simulate the grid and determine the optimal decisions in order to combine and distribute energy sources within the grid. Since coordinating the large number of distributed nodes will be quite challenging, Hug has proposed a distributed energy management approach which uses intelligence to balance supply and demand.
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In spite of vast success in the theoretical and numerical studies of DP, obtaining convincing experimental evidence has proved challenging. However, in 2007, critical behavior of DP was finally found in the electrohydrodynamic convection of liquid crystal, where a complete set of static and dynamic critical exponents and universal scaling functions of DP were measured in the transition to spatiotemporal intermittency between two turbulent states. Temporal networks can be studied using the mapping to the directed percolation problem. The probability of temporal links has a critical value below which the connectedness is zero while above almost all nodes can be connected.
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According to the company's plans, Tidal Lagoon Swansea Bay could operate 14 hours per day with a maximum output of 320 MW (nameplate capacity), and power the equivalent of around 155,000 homes. There are different ways to evaluate tidal energy output. The Government considered intermittency due to the tides and that the Tidal Lagoon Swansea Bay would have had a load factor of 19% compared to around 50% for offshore wind power. However, as the monthly variation is predictable Tidal Lagoon energy could allow reduction in the amount of energy generated by gas- fired power plants.
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A drop in fossil fuel prices then led the federal and state governments to dismantle the policy framework that had supported the advancement of CSP. In 2006, the market re-emerged in Spain and the United States, supported by changes in governmental policies favorable to renewable energies – and solar in particular. CSP uses renewable solar resource to generate electricity while producing no GHG emissions (SOX, CO2) with large scale power capacities. CSP plants can be combined with thermal storage capacity so as to avoid intermittency due to clouds, or to provide the grid with electricity in the evening, during peak hours, and throughout the night.
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On March 1, 2012, a "wind power coordinated control system" was implemented to adjust the output of the 18 wind farms of the Gansu Wind Farm Project, which total 10 GW, to meet the needs of the transmission grid, which is limited to 1.5 GW. This permitted the production of 1 GWh more per day than previously, and greatly improves the system's stability. Curtailment of wind turbine operations is a first order method for dealing with the intermittency of wind, but normally loses available output when the power grid's transmission capacity has been reached. Other methods involve either added local industrial usage or added local storage capacity.
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A geothermal heat pump (GHP) or ground source heat pump (GSHP) is a central heating and/or cooling system that transfers heat to or from the ground. It uses the earth all the time, without any intermittency, as a heat source (in the winter) or a heat sink (in the summer). This design takes advantage of the moderate temperatures in the ground to boost efficiency and reduce the operational costs of heating and cooling systems, and may be combined with solar heating to form a geosolar system with even greater efficiency. They are also known by other names, including geoexchange, earth-coupled, earth energy systems.
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1–2, the transition by temporal Intermittency, which was confirmed by numerous experimental observations and CFD simulations. This is the so-called Pomeau–Manneville scenario, associated with the Pomeau- Manneville maps Pomeau, Y.; Manneville, P. (1980). "Intermittent Transition to Turbulence in Dissipative Dynamical Systems". Commun. Math. Phys. 74 (2): 189–197 In papers published in 1973 and 1976, Hardy, Pomeau and de Pazzis Hardy, J., Pomeau, Y., and De Pazzis, O. «Time evolution of a two-dimensional classical lattice system.» Physical Review Letters 31.5 (1973): 276.. Hardy, J., De Pazzis, O. , and Pomeau, Y. « Molecular dynamics of a classical lattice gas: Transport properties and time correlation functions.» Physical review A 13.5 (1976): 1949.
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The importance will be revealed by Pomeau himself (and a collaborator, Paul Manneville) through the "scenario" of Intermittency, proposed in 1979. The second path suggested by Pomeau and Ibanez is the idea of realizing dynamical systems even simpler than that of Lorenz, but having similar characteristics, and which would make it possible to prove more clearly "evidences" brought to light by numerical calculations. Since the reasoning is based on Poincaré's section, he proposes to produce an application of the plane in itself, rather than a differential equation, imitating the behavior of Lorenz and its strange attractor. He builds one in an ad hoc manner which allows him to better base his reasoning.
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Renewable energy sources, such as solar photovoltaics, wind, wave, and tidal, are, due to their intermittency, not considered as supplying "base load" but will still add power to the grid. The remaining or 'peak' power demand, is supplied by peaking power plants, which are typically smaller, faster-responding, and higher cost sources, such as combined cycle or combustion turbine plants fueled by natural gas. Long- distance transmission of electricity (hundreds of kilometers) is cheap and efficient, with costs of US$0.005–0.02 per kWh (compared to annual averaged large producer costs of US$0.01–0.025 per kWh, retail rates upwards of US$0.10 per kWh, and multiples of retail for instantaneous suppliers at unpredicted highest demand moments). Thus distant suppliers can be cheaper than local sources (e.g.
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Peak load leveling can enable new ways for utilities to provide regulation services (keeping voltage and frequency stable) and provide spinning reserves (meet sudden demands for power). These services coupled with "smart-meters" would allow V2G vehicles to give power back to the grid and in return, receive monetary benefits based on how much power given back to the grid. In its current development, it has been proposed that such use of electric vehicles could buffer renewable power sources such as wind power for example, by storing excess energy produced during windy periods and providing it back to the grid during high load periods, thus effectively stabilizing the intermittency of wind power. Some see this application of vehicle-to-grid technology as an approach to help renewable energy become a base load electricity technology.
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Fluorescence intermittency, or blinking, is the phenomenon of random switching between ON (bright) and OFF (dark) states of the emitter under its continuous excitation. It is a common property of the nanoscale emitters (molecular fluorophores, colloidal quantum dots) related to the competition between the radiative and non-radiative relaxation pathways. The peculiar feature of such blinking in most cases is the power-law (in contrast to exponential) statistics of the ON and OFF time distributions, meaning that the measurements of the time-averaged intensity of a single emitter is not reproducible in different experiments and implying a complex dynamics of the involved process. In other words, in one experiment the emitter can blink frequently, while in another it may stay ON (or OFF) for almost entire length of the experiment (even for extremely long measurement times).
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During his PhD he worked on studies of chaos and fractal dimensions and with Per Bak and Tomas Bohr he discovered universal scaling structure of mode locking between two frequencies at the onset of chaos. Following his PhD in 1984, he continued his academic career as a postdoc at the James Franck Institute in Chicago, with Leo Kadanoff as his supervisor. Here he contributed to a series of highly influential papers, and most notably he played a key part in the development of multi fractals . He later worked on fully developed turbulence and together with Giovanni Paladin and Angelo Vulpiani he pioneered the study of intermittency correction in term of shell models . He was the head of ‘Center for Chaos and Turbulence Studies: CATS’ before he in 2004 he became the director of ‘BioNET: Danish Center for Biophysics’.
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He found that the correlation > coefficient of wind power fell from 0.6 at 200 km to 0.25 at 600 km > separation (a perfect correlation would have a coefficient equal to 1.0.) > There were no hours in the data set where wind speed was below the cut-in > wind speed of a modern wind turbine throughout the United Kingdom, and low > wind speed events affecting more than 90 per cent of the United Kingdom had > an average recurrent rate of only one hour per year. Diesendorf goes on to say that every conventional power station breaks down unexpectedly from time to time, causing an immediate loss of all its power. That is true intermittency, according to Diesendorf, and it is a particular type of variability that switches between full power and no power. Once a conventional power station has broken down, it may be offline for weeks, much longer than windless periods.
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Boedo has also made significant contributions in diagnostic development for plasmas. He is known for the development of high heat flux, fixed and reciprocating, scanning probes, such as that built for the NSTX tokamak, a rotating Langmuir probe, and also an innovative diagnostic to measure electron temperature with better than 400 kHz bandwidth. Main 8 Publications (by meaning and impact) -Experimental evidence of edge intrinsic momentum source driven by kinetic ion loss and edge radial electric fields in tokamaks. -Transport by intermittent convection in the boundary of the DIII-D tokamak, PoP 8 (11) 4826, 2001 -Transport by intermittency in the boundary of the DIII-D tokamak, PoP 10 (5) 1670, 2003 -Enhanced particle confinement and turbulence reduction due to ExB shear in the TEXTOR tokamak, Nuc. Fuc. 40 (7), 1397, 2000 -Edge-localized mode dynamics and transport in the scrape-off layer of the DIII-D tokamak, Nuc. Fus., 45 (10), S168, 2005 -Scaling of plasma turbulence suppression with velocity shear, PoP, 7 (9), 3663, 2000 -Suppression of temperature fluctuations and energy barrier generation by velocity shear, PRL, 49 (10), 104016, 2009 -On the harmonic technique to measure electron temperature with high time resolution, RSI, 0 (7), 2997, 1999 -Electric field-induced plasma convection in tokamak divertors, PoP, 15 (3), 2008 Other contributions (invited talks, services, etc.) 2014 APS DPP, New Orleans, Louisiana, invited talk 2008 EPS invited talk.
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