Integrating electricity markets: Impacts of increasing trade on prices and emissions in the western United States

This paper presents empirically-estimated average hourly relationships between regional electricity trade in the United States and prices, emissions, and generation from 2015 through 2018. Consistent with economic theory, the analysis finds a negative relationship between electricity prices in California and regional trade, conditional on local demand. Each 1 gigawatt-hour increase in California electricity imports is associated with an average $0.15 per megawatt-hour decrease in the California Independent System Operator's wholesale electricity price. There is a net-negative short term relationship between carbon dioxide emissions in California and electricity imports that is partially offset by positive emissions from exporting neighbors. Specifically, each 1 GWh increase in regional trade is associated with a net 70-ton average decrease in CO2 emissions across the western U.S., conditional on demand levels. The results provide evidence that electricity imports mostly displace natural gas generation on the margin in the California electricity market. A small positive relationship is observed between short-run SO2 and NOx emissions in neighboring regions and California electricity imports. The magnitude of the SO2 and NOx results suggest an average increase of 0.1 MWh from neighboring coal plants is associated with a 1 MWh increase in imports to California

Recent Progress in Shearlet Theory: Systematic Construction of Shearlet Dilation Groups, Characterization of Wavefront Sets, and New Embeddings

The class of generalized shearlet dilation groups has recently been developed to allow the unified treatment of various shearlet groups and associated shearlet transforms that had previously been studied on a case-by-case basis. We consider several aspects of these groups: First, their systematic construction from associative algebras, secondly, their suitability for the characterization of wavefront sets, and finally, the question of constructing embeddings into the symplectic group in a way that intertwines the quasi-regular representation with the metaplectic one. For all questions, it is possible to treat the full class of generalized shearlet groups in a comprehensive and unified way, thus generalizing known results to an infinity of new cases. Our presentation emphasizes the interplay between the algebraic structure underlying the construction of the shearlet dilation groups, the geometric properties of the dual action, and the analytic properties of the associated shearlet transforms.Comment: 28 page

Besov regularity for operator equations on patchwise smooth manifolds

We study regularity properties of solutions to operator equations on patchwise smooth manifolds $\partial\Omega$ such as, e.g., boundaries of polyhedral domains $\Omega \subset \mathbb{R}^3$. Using suitable biorthogonal wavelet bases $\Psi$, we introduce a new class of Besov-type spaces $B_{\Psi,q}^\alpha(L_p(\partial \Omega))$ of functions $u\colon\partial\Omega\rightarrow\mathbb{C}$. Special attention is paid on the rate of convergence for best $n$-term wavelet approximation to functions in these scales since this determines the performance of adaptive numerical schemes. We show embeddings of (weighted) Sobolev spaces on $\partial\Omega$ into $B_{\Psi,\tau}^\alpha(L_\tau(\partial \Omega))$, $1/\tau=\alpha/2 + 1/2$, which lead us to regularity assertions for the equations under consideration. Finally, we apply our results to a boundary integral equation of the second kind which arises from the double layer ansatz for Dirichlet problems for Laplace's equation in $\Omega$.Comment: 42 pages, 3 figures, updated after peer review. Preprint: Bericht Mathematik Nr. 2013-03 des Fachbereichs Mathematik und Informatik, Universit\"at Marburg. To appear in J. Found. Comput. Mat

Optimal Approximation of Elliptic Problems by Linear and Nonlinear Mappings I

We study the optimal approximation of the solution of an operator equation Au=f by linear and nonlinear mappings

Optimal Approximation of Elliptic Problems by Linear and Nonlinear Mappings III: Frames

We study the optimal approximation of the solution of an operator equation by certain n-term approximations with respect to specific classes of frames. We study worst case errors and the optimal order of convergence and define suitable nonlinear frame widths. The main advantage of frames compared to Riesz basis, which were studied in our earlier papers, is the fact that we can now handle arbitrary bounded Lipschitz domains--also for the upper bounds. Key words: elliptic operator equation, worst case error, frames, nonlinear approximation, best n-term approximation, manifold width, Besov spaces on Lipschitz domainsComment: J. Complexity, to appear. Final version, minor mistakes correcte

Photoassociation of 40Ca at high laser intensities

In this thesis I present the results of photoassociation measurements in ensembles of atomic calcium over an intensity range of below 1 W/cm2 up to 600 W/cm2. The temperature of the atoms was reduced to 1 μK by laser and evaporative cooling. Afterwards the two most-weakly bound states in the excited molecular potentials that dissociate to the asymtote 3P1+1S0 have been investigated regarding the shape and absolute rate of the resonances. The investigation showed that the measured rates differ by more than an order of magnitude compared to theoretical calculations. The predictions are based on a scattering formalism by Bohn & Julienne and wave functions derived from coupled-channel calculations. The shape of the resonances, the width in particular, agrees well with the numerical calculations. Especially the power broadening at high intensity is reproduced by the experiment. Further the light shift introduced by the photoassociation laser has been measured which also differs from the predictions. In the further course of the thesis the numerical simulations were improved by considering additional influences like the exact dependence of the Franck-Condon density and the light shift of the photoassociation laser as a function of the collision energy. Additionally the modeling of the experimental setup with a special emphasis on the volume of the optical trap and thus the density of the atomic ensemble was improved and the influence of varying trap depth and photoassociation duration has been studied. Investigating possible explanations for the discrepancy of the measured rates compared to theory, I show that by a modification of the coupling parameter and the spontaneous decay rate of the molecular state the rates measured in the experiment can be reproduced theoretically, with the restriction that at high intensity the calculated line shape no longer agrees with the measurement. In the last chapter an improved experimental apparatus is presented that by using an optical lattice suppresses thermal broadening and thus simplifies the analysis substantially

Grid-Scale Energy Storage for Integrating Renewable Energy: Updates on FERC Order 755 and DOE-Funded Demonstration Projects

Energy storage is an important technology for overcoming intermittency issues and increasing renewable energy development. Storage provides valuable services to a grid with high penetrations of variable renewable generation. In this paper a background of electricity markets and the regulatory environment in the United States is provided to give context. Then, implications from FERC Order 755 and frequency regulation compensation issues are explored, with a particular focus on the Midwest Independent System Operator (MISO). Finally, updates of ongoing federal-funded energy storage demonstration projects are presented

Corn Silage to Beef Calculator

The Corn Silage to Beef calculator allows corn silagevarieties to be summarized in terms of the beef they willyield as a feedstuff. This software has been made availablet the general public through Iowa State Beef Center website as a free download athttp://iowabeefcenter.org/calculators.htm

Cattle Feeding Benchmark Data: Fall & Winter 2015 Spring & Summer 2016

The decline in fed cattle prices from the summer of 2015 has continued now through the summer of 2016. Feed and feeder calf prices have also declined as reflected in the breakeven values. Market weights have declined slightly through the year, but are still fairly large when compared back to weights of three years ago. Feeding losses were not as extreme as they were a year ago, but they are still not favorable