Price Volatility and Banking in Green Certificate Markets

There is concern that prices in a market for Green Certificates (GCs) primarily based on volatile wind power will fluctuate excessively, leading to corresponding volatility of electricity prices. Applying a rational expectations simulation model of competitive storage and speculation of GCs the paper shows that the introduction of banking of GCs may reduce price volatility considerably and lead to increased social surplus. Banking lowers average prices and is therefore not necessarily to the benefit of “green producers”. Proposed price bounds on GC-prices will reduce the importance of banking and even of the GC system itself.electricity; environment; commodity speculation; green certificates; marketable permits; uncertainty

Price Volatility and Banking in Green Certificate Markets

There is concern that prices in a market for Green Certificates (GCs) primarily based on volatile wind power will fluctuate excessively, leading to corresponding volatility of electricity prices. Applying a rational expectations simulation model of competitive storage and speculation of GCs the paper shows that the introduction of banking of GCs may reduce price volatility considerably and lead to increased social surplus. Banking lowers average prices and is therefore not necessarily to the benefit of “green producers”. Proposed price bounds on GC -prices will reduce the importance of banking and even of the GC system itself.Electricity; Green Certificates; Uncertainty; Commodity Speculation

PANIC: A Near-infrared Camera for the Magellan Telescopes

PANIC (Persson's Auxiliary Nasmyth Infrared Camera) is a near-infrared camera designed to operate at any one of the f/11 folded ports of the 6.5m Magellan telescopes at Las Campanas Observatory, Chile. The instrument is built around a simple, all-refractive design that reimages the Magellan focal plane to a plate scale of 0.125'' pixel^{-1} onto a Rockwell 1024x1024 HgCdTe detector. The design goals for PANIC included excellent image quality to sample the superb seeing measured with the Magellan telescopes, high throughput, a relatively short construction time, and low cost. PANIC has now been in regular operation for over one year and has proved to be highly reliable and produce excellent images. The best recorded image quality has been ~0.2'' FWHM.Comment: 8 pages, 5 figures. To appear in "Astronomical Telescopes and Instrumentation," Proc SPIE (Glasgow), June 2004. Version with higher resolution figures is available at http://cfa-www.harvard.edu/~pmartini/professional/publications/panic.pd

Interactive comment on “Influence of aquifer heterogeneity on karst hydraulics and catchment delineation employing distributive modeling approaches”

Due to their heterogeneous nature, karst aquifers pose a major challenge for hydrogeological investigations. Important procedures like the delineation of catchment areas for springs are hindered by the unknown locations and hydraulic properties of highly conductive karstic zones. In this work numerical modeling was employed as a tool in delineating catchment areas of several springs within a karst area in southwestern Germany. For this purpose, different distributive modeling approaches were implemented in the finite element simulation software Comsol Multiphysics®. The investigation focuses on the question to which degree the effect of karstification has to be taken into account for accurately simulating the hydraulic head distribution and the observed spring discharges. The results reveal that the representation of heterogeneities has a large influence on the delineation of the catchment areas. Not only the location of highly conductive elements but also their geometries play a major role for the resulting hydraulic head distribution and thus for catchment area delineation. The size distribution of the karst conduits derived from the numerical models agrees with knowledge from karst genesis. It was thus shown that numerical modeling is a useful tool for catchment delineation in karst aquifers based on results from different field observations

Single-inhaler fluticasone furoate/umeclidinium/vilanterol versus fluticasone furoate/vilanterol plus umeclidinium using two inhalers for chronic obstructive pulmonary disease: A randomized non-inferiority study

Background: Single-inhaler fluticasone furoate/umeclidinium/vilanterol (FF/UMEC/VI) 100/62.5/25 μg has been shown to improve lung function and health status, and reduce exacerbations, versus budesonide/formoterol in patients with chronic obstructive pulmonary disease (COPD). We evaluated the non-inferiority of single-inhaler FF/UMEC/VI versus FF/VI + UMEC using two inhalers. Methods: Eligible patients with COPD (aged ≥40 years; ≥1 moderate/severe exacerbation in the 12 months before screening) were randomized (1:1; stratified by the number of long-acting bronchodilators [0, 1 or 2] per day during run-in) to receive 24-week FF/UMEC/VI 100/62.5/25 μg and placebo or FF/VI 100/25 μg + UMEC 62.5 μg; all treatments/placebo were delivered using the ELLIPTA inhaler once-daily in the morning. Primary endpoint: change from baseline in trough forced expiratory volume in 1 s (FEV1) at Week 24. The non-inferiority margin for the lower 95% confidence limit was set at − 50 mL. Results: A total of 1055 patients (844 [80%] of whom were enrolled on combination maintenance therapy) were randomized to receive FF/UMEC/VI (n = 527) or FF/VI + UMEC (n = 528). Mean change from baseline in trough FEV1 at Week 24 was 113 mL (95% CI 91, 135) for FF/UMEC/VI and 95 mL (95% CI 72, 117) for FF/VI + UMEC; the between-treatment difference of 18 mL (95% CI -13, 50) confirmed FF/UMEC/VI’s was considered non-inferior to FF/ VI + UMEC. At Week 24, the proportion of responders based on St George’s Respiratory Questionnaire Total score was 50% (FF/UMEC/VI) and 51% (FF/VI + UMEC); the proportion of responders based on the Transitional Dyspnea Index focal score was similar (56% both groups). A similar proportion of patients experienced a moderate/severe exacerbation in the FF/UMEC/VI (24%) and FF/VI + UMEC (27%) groups; the hazard ratio for time to first moderate/ severe exacerbation with FF/UMEC/VI versus FF/VI + UMEC was 0.87 (95% CI 0.68, 1.12). The incidence of adverse events was comparable in both groups (48%); the incidence of serious adverse events was 10% (FF/UMEC/VI) and 11% (FF/VI + UMEC). Conclusions: Single-inhaler triple therapy (FF/UMEC/VI) is non-inferior to two inhalers (FF/VI + UMEC) on trough FEV1 change from baseline at 24 weeks. Results were similar on all other measures of efficacy, health-related quality of life, and safety. Trial registration: GSK study CTT200812; ClinicalTrials.gov NCT02729051 (submitted 31 March 2016)

In situ acceleration in the galactic center arc

For the nonthermal radio emission of the Galactic Center Arc in situ electron acceleration is imperative. The observed radio spectrum can be modeled by a transport equation for the relativistic electrons which includes particle acceleration by electric fields, momentum diffusion via scattering by magnetohydrodynamical turbulence and energy losses by synchrotron radiation. The accelerating electric fields can be regarded as a natural consequence of multiple reconnection events, caused by the interaction between a molecular cloud and the Arc region. The radio spectrum and even the recently detected 150 GHz emission, explicitely originating from the interaction regions of a molecular cloud with the magnetized Arc, can be explained in terms of quasi-monoenergetically distributed relativistic electrons with a typical energy of about 10 GeV accelerated in stochastically distributed magnetic reconnection zones

Addressing the Climate Problem:Choice between Allowances, Feed-in Tariffs and Taxes

Instruments chosen to pursue climate related targets are not always efficient. In this paper we consider an economy with three climate related targets for its electricity generation: a given share of “green” electricity, a given expansion of “green” electricity, and a given reduction of “black” (fossil based) electricity. At its disposal the country has three instruments: an allowance system (tradable green certificates), a subsidy system (feed-in tariffs) and a Pigouvian fossil tax. Each of these instruments may be used to attain any of the given targets. Within the setting of the model it is verified that each kind of the target has only a single efficient instrument under certainty, and that there is a deadweight loss of using other instruments to achieve the target. Similarly, there is also an analysis of instrument choice when several targets are to be attained at the same time. The paper also discusses the case of simultaneous targets as well as the relevance of the various targets

Adaptive modelling of dynamic brittle fracture - a combined phase field regularized cohesive zone model and scaled boundary finite element approach

Based on the error indicator computed from the scaled boundary equations, a quadtree based adaptive phase-field method is proposed for dynamic brittle fracture problems in isotropic material using the scaled boundary finite element method (SBFEM). The use of SBFEM alleviates the need for additional: (a) constraints to handle hanging nodes resulting from adaptive refinement and (b) post-processing techniques. Three representative examples are solved to demonstrate the efficiency of the proposed approach. From the numerical study, it is opined that the proposed approach requires an order of magnitude fewer degrees of freedom when compared to uniform refinement and can capture the crack morphology under dynamic loading conditions without compromising accuracy

Faecal Steroids and n-Alkanes in Lake Sediments

Lake sediments are used as archives for climate and environmental reconstructions. This study investigated if biomarker analyses in lake sediments can be used to reconstruct anthropogenic landscape modifications during Holocene. In contrast to the mineral matrix of sediments and e.g. pollen, plant macro remains and charcoal particles, biomarkers can be more easily translocated within soil profiles before erosion and deposition. Furthermore, a translocation can also occur in lake sediments. Therefore, we tested if biomarker concentrations and patterns correlated with pollen patterns and further paleo environmental proxies in sediments of two maar lakes in the Eifel region. Five core sections of Lake Holzmaar and two core sections of Lake Ulmener Maar were sampled. The analysed core sections contain ca. 10 000 years and a number of data existed from previous analyses (ELSA project). As example for biomarkers for the reconstruction of vegetation changes, n-alkanes were analysed. Steroids incl. bile acids were used as proxies for the deposition of faeces of animals (animal husbandry). Patterns of n-alkanes correlated with pollen data. Parts of the core that show characteristics of dense forest in the catchment area had relatively low amounts of faecal steroids and the steroid patterns indicated the presence of several different animals. In parts of the core that show characteristics for grassland and agricultural fields, faecal steroids showed the presence of animal husbandry. The correlation of biomarker concentrations with pollen data and other data showed that it possible to detect changes in vegetation and land use with biomarker analyses within the catchment area of the two maar lakes