106 research outputs found
Nodal prices, capacity valuation and investments in natural gas markets - Overview and Analytical Framework
Especially in the short-term, prices in natural gas markets are not exclusively determined by overall supply and demand, but also by the availability of the transport infrastructure. If transportation capacity is scarce, prices may form in (local) residual markets and can differ regionally. If available, storages provide intertemporal arbitrage possibilities which also impact prices. Temporal and regional price differences, in turn, determine the value of storage and transport capacity if either one is scarce. This paper applies an analytical framework for a simple pipeline grid with a storage over two periods to illustrate the interdependencies between prices, scarce capacity and capacity value. The theoretically optimal transportation and storage tariffs are described analytically. The optimal pipeline investment size is shown to be related to marginal storage investment and a function of the discounted and aggregated cost of congestion over the lifetime's asset.Natural gas; Prices; Transport capacity; Storage; Investment
Civil Unrest in North Africa – Risks for Natural Gas Supply?
The uprising and military confrontation in Libya that began in February 2011 has led to disruptions of gas supplies to Europe. An analysis of how Europe has compensated for these missing gas volumes shows that this situation has not affected security of supply. However, this situation would change if the North African uprising were to spread to Algeria. Since Algeria is a much more important gas supplier to Europe than is Libya, more severe consequences would be likely. Applying a natural gas infrastructure model, we investigate the impact of supplier disruptions from both countries for a summer and winter period. Our analysis shows that disruptions in the low-demand summer months could be compensated for, mainly by LNG imports. An investigation of a similar situation at the beginning of the winter shows that security of supply would be severely compromised and that disruptions to Italian consumers would be unavoidable.Natural gas; security of supply; network modelling; North Africa
German Foreign Direct Investment and Wages
Over the last decade, German multinationals created about two million jobs abroad with increasing foreign direct investment (FDI). While there are many reasons for firms to go multinational and probably just as many for Germany's high unemployment, this paper aims to investigate the relationship between domestic labour costs and foreign direct investment. We apply a theoretical model for an econometric analysis examining the determinants of FDI using panel data of German firms' foreign capital stocks in 22 countries between 1994 and 2003. Estimating elasticities, we find that while domestic wages do not significantly influence total FDI by German firms, they positively affect the FDI stock in countries where cheap labour is abundant. Thus, although Germany's high labour costs are not the sole driver of foreign direct investment, they may accelerate the outsourcing of German jobs. --Foreign direct investment,wages,trade,German multinational firms
The Economics of Natural Gas Infrastructure Investments - Theory and Model-based Analysis for Europe
Changing supply structures, security of supply threats and efforts to eliminate bottlenecks and increase competition in the European gas market potentially warrant infrastructure investments. However, which investments are actually efficient is unclear.
From a theoretical perspective, concepts from other sectors regarding the estimation of congestion cost and efficient investment can be applied - with some extensions - to natural gas markets. Investigations in a simple analytical framework, thereby, show that congestion does not necessarily imply that investment is efficient, and that there are multiple interdependencies between investments in different infrastructure elements (pipeline grid, gas storage, import terminals for liquefied natural gas (LNG)) which need to be considered in an applied analysis.
Such interdependencies strengthen the case for a model-based analysis. An optimization model minimizing costs can illustrate the first-best solution with respect to investments in natural gas infrastructure; gas market characteristics such as temperature-dependent stochasticity of demand or the lumpiness of investments can be included. Scenario analyses help to show the effects of changing the underlying model presumption. Hence, results are projections subject to data and model assumption - and not forecasts. However, as they depict the optimal, cost-minimizing outcome, results provide a guideline to policymakers and regulators regarding the desirable market outcome.
A stochastic mixed-integer dispatch and investment model for the European natural gas infrastructure is developed as an optimization model taking the theoretical inter-dependencies into account. It is based on an extensive infrastructure database including long-distance transmission pipelines, LNG terminals and gas storage sites with a high level of spatial granularity. It is parameterized with assumptions on supply and demand developments as well as empirically derived infrastructure extension costs to perform model simulations of the European gas market until 2025.
In the framework of the conservative demand forecast of the European Commission, efficient infrastructure expansion (starting from the 2010 infrastructure with all projects under construction being completed) is limited. The constant demand in combination with the newly created import capacities on the LNG (UK, Spain) and pipeline (Nord Stream, Medgaz) side means the gas infrastructure is well equipped to deal with declining European production. The reduction of flexibility provided by domestic production is compensated by flexible LNG imports if the global LNG market remains well supplied.
Further scenario analyses illustrate the effects of changing the presumptions on supply and demand: A low LNG price does not increase LNG investments significantly, but reduces the requirements for pipeline investments in Europe, especially in East to West direction on the continent. An assumed decline in the flexibility of LNG imports in Europe, conversely, would greatly reduces efficient LNG capacity additions as the option to flexibly import natural gas is one of the favorable characteristics of such facilities. Consequently, investments in natural gas storage would have to increase substantially to provide flexibility through a different technology. This is also true if flexible LNG is replaced by either additional gas volumes imported via long-distance transmission pipelines from the Caspian region or if it is substituted by gas production from unconventional sources in Europe. Rising demand, intuitively, requires additional investments.
The simulation of security of supply emergency scenarios demonstrates that redundant infrastructure capacities and gas stocks in excess of the volumes required to balance supply and demand can be efficient - even if the emergency probability is low.
Modeling a one-month disruption of Russian transits via Ukraine and Belarus in 2020 shows that the infrastructure is rather resilient against such a threat. Reasons are alternative routes such as Nord Stream and the infrastructure investments made in the aftermath of the 2009 Ukraine transit disruption. Only limited additional investment in interconnection capacities between countries in Eastern Europe are found to be efficient. However, it also becomes evident that, with an emergency probability as low as two percent, it is efficient to stock up to 10 billion cubic meter of natural gas additionally in European gas storage facilities.
Conversely, the infrastructure is found to be less resilient regarding a prolonged supply stop from North Africa as seen for Libya since February 2011. Italy would be affected particularly from a combined export disruption in Libya and Algeria, making significant investments in interconnections with Central and Northern Europe efficient. Additionally, further LNG import capacities would also be efficient to mitigate the consequences of a North African pipeline export stop. These investments in redundant import capacities become more efficient the higher the probability of the emergency.
The analysis yields implications for natural gas infrastructure investments. With respect to the general results, it is illustrated how developments in one region (unconventional gas production, a new import corridor from the Caspian region) have significant implications for investments in geographically separated markets. The efficiency of investments in additional storage capacity is greatly affected by developments in the global LNG market and the composition of the European supply mix. Investments in redundant capacity to enhance security of supply are also found to be beneficial even if the probability of the respective emergency is low. However, it is also shown that a detailed analysis is required to identify specific, means-tested investment options - universal infrastructure standards may be of limited value. Furthermore, investments benefiting one region may efficiently take place outside the borders of that region. Important questions for further research, then, are (i) how these efficient investments can be incentivized through a regulatory framework and (ii) who bears their costs, which implicitly includes the question whether or not short-term security of supply is a public good.
Regarding the applied analysis, further work may also target an improved modeling of interdependencies of the infrastructure system with natural gas consumption in the power and industry sectors (demand side management)
Analyse von Grenzkostenpreisen im Europaeischen Gasmarkt
Der An- und Verkauf von Erdgas an Grosshandelsmaerkten wird in einem zunehmend liberalisierten Gasmarkt auch in Kontinentaleuropa weiter an Bedeutung gewinnen. Die Preise an diesen Maerkten bilden sich aus Angebot und Nachfrage; wie in jeder netzgebundenen Industrie kommt der Infrastruktur und ihrer Verfuegbarkeit dabei jedoch eine wichtige Rolle zu. Mit Hilfe des Ergasinfrastruktur- und Dispatchmodells Tiger werden in dieser Arbeit Grenzkostenpreise fuer ausgewaehlte europaeische Handelspunkte geschaetzt. Die Grundlage dafuer bildet ein most-likely Szenario fuer die Entwicklung des europaeischen Gasmarktes bis zum Jahr 2018. Die aktuell in der Realitaet zu beobachtende hohe Korrelation der europaeischen Boersenpreise fuer Erdgas untereinander kann dabei mit dem Modell nachvollzogen werden. Getrieben durch die Entwicklung von Angebot und Nachfrage zeigt sich jedoch, dass signifikant unterschiedliche Grenzkostenpreise in Nordwest- und Zentraleuropa in der naechsten Dekade temporaer auftreten koennen. Grund dafuer sind Infrastrukturengpaesse in Zeiten hoher Nachfrage.Erdgas; Europaeischer Gasmarkt; Erdgaspreise; Modellierung
The potential of natural gas as a bridging technology in low-emission road transportation in Germany
Greenhouse gas emission reductions are at the centre of national and international efforts to mitigate climate change. In road transportation, many politically incentivised measures focus on increasing the energy efficiency of established technologies, or promoting electric or hybrid vehicles. The abatement potential of the former approach is limited, electric mobility technologies are not yet market-ready. In a case study for Germany, this paper focuses on natural gas powered vehicles as a bridging technology in road transportation. Scenario analyses with a low level of aggregation show that natural gas-based road transportation in Germany can accumulate up to 464 million tonnes of CO2-equivalent emission reductions until 2030 depending on the speed of the diffusion process. If similar policies were adopted EU-wide, the emission reduction potential could reach a maximum of about 2.5 billion tonnes of CO2-equivalent. Efforts to promote natural gas as a bridging technology may therefore contribute to significant emissions reductions
Post-mortem computed tomography is a useful tool for determining the pulmonary ventilation status in newborns
<jats:title>Abstract</jats:title><jats:sec>
<jats:title>Introduction</jats:title>
<jats:p>Lung ventilation is a standard sign of life in newborns. Post-mortem computed tomography (PMCT) is highly sensitive to the presence of gas in the body including the lungs. Current standard examinations to determine the pulmonary ventilation status in newborns are the flotation test and histology. The purpose of this study was to compare the accuracy of PMCT with the flotation test for determining the lung ventilation status with histological control as reference standard. A cut-off value as CT number in Hounsfield Units (HU) determining lung ventilation of newborns in PMCT should be established.</jats:p>
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<jats:title>Methods</jats:title>
<jats:p>A total of 38Â infant lungs were examined of which 21Â lungs were from infants deceased shortly after live birth (control group) and 17Â lungs belonged to infants where live birth was in question (study group). All lungs were examined using PMCT, flotation test, and histological examination.</jats:p>
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<jats:title>Results</jats:title>
<jats:p>The control group showed an overall mean attenuation ± standard deviation of −219 HU ± 135; the study group of 45 ± 15 HU in histologically nonventilated lungs versus −192 ± 207 HU; (<jats:italic>p</jats:italic> &lt; 0.001) in ventilated lungs. The best cut-off value for optimal discrimination of ventilated and nonventilated lungs in newborns was −35 mean HU.</jats:p>
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<jats:title>Conclusion</jats:title>
<jats:p>PMCT is equally well suited to determine lung ventilation as the flotation test. It provides additional information regarding pulmonary infiltration, degree of putrefaction, or signs of trauma (fractures, pneumothorax). Histology remains mandatory in ambiguous cases.</jats:p>
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Organometallic-Organic Hybrid Polymers Assembled from Pentaphosphaferrocene, Bipyridyl Linkers, and Cul Ions
A multicomponent approach of the P-n ligand complex [Cp*Fe((5)-P-5)] (1: Cp* = (5)-C5Me5) with the ditopic organic linkers 4,4-bipyridine (2) or trans-1,2-di(pyridine-4-yl)ethene (3) in the presence of Cu-I salts of the anions [BF4](-) and [PF6](-) or the coordinating anion Br-, leads to the formation of four novel organometallic-organic hybrid polymers: the cationic 1D polymeric compounds [Cu-4{Cp*Fe(mu(3),(5:1:1)-P-5)}(2)(mu,(1:1)-C10H8N2)(4)(CH3CN)(4)](n)[BF4](4n) (4) and [Cu-4{Cp*Fe(mu(3),(5:1:1)-P-5)}(2)(mu,(1:1)-C10H8N2)(4)(CH3CN)(4)](n)[PF6](4n) (5) as well as the unique neutral threefold 2D 2D interpenetrated networks [Cu2Cl2{Cp*Fe(mu(3),(5:1:1)-P-5)}(mu,(1:1)-C12H10N2)](n) (6) and [Cu2Br2{Cp*Fe(mu(3),(5:1:1)-P-5)}(mu,(1:1)-C10H8N2)](n) (7)
Usefulness of EEG Techniques in Distinguishing Frontotemporal Dementia from Alzheimer's Disease and Other Dementias
The clinical distinction of frontotemporal dementia (FTD) and Alzheimer's disease (AD) may be difficult. In this narrative review we summarize and discuss the most relevant electroencephalography (EEG) studies which have been applied to demented patients with the aim of distinguishing the various types of cognitive impairment. EEG studies revealed that patients at an early stage of FTD or AD displayed different patterns in the cortical localization of oscillatory activity across different frequency bands and in functional connectivity. Both classical EEG spectral analysis and EEG topography analysis are able to differentiate the different dementias at group level. The combination of standardized low-resolution brain electromagnetic tomography (sLORETA) and power parameters seems to improve the sensitivity, but spectral and connectivity biomarkers able to differentiate single patients have not yet been identified. The promising EEG findings should be replicated in larger studies, but could represent an additional useful, noninvasive, and reproducible diagnostic tool for clinical practice
COVID-19 and Intracranial Hemorrhage: A Multicenter Case Series, Systematic Review and Pooled Analysis
Introduction: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) profoundly impacts hemostasis and microvasculature. In the light of the dilemma between thromboembolic and hemorrhagic complications, in the present paper, we systematically investigate the prevalence, mortality, radiological subtypes, and clinical characteristics of intracranial hemorrhage (ICH) in coronavirus disease (COVID-19) patients. Methods: Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we performed a systematic review of the literature by screening the PubMed database and included patients diagnosed with COVID-19 and concomitant ICH. We performed a pooled analysis, including a prospectively collected cohort of critically ill COVID-19 patients with ICH, as part of the PANDEMIC registry (Pooled Analysis of Neurologic Disorders Manifesting in Intensive Care of COVID-19). Results: Our literature review revealed a total of 217 citations. After the selection process, 79 studies and a total of 477 patients were included. The median age was 58.8 years. A total of 23.3% of patients experienced the critical stage of COVID-19, 62.7% of patients were on anticoagulation and 27.5% of the patients received ECMO. The prevalence of ICH was at 0.85% and the mortality at 52.18%, respectively. Conclusion: ICH in COVID-19 patients is rare, but it has a very poor prognosis. Different subtypes of ICH seen in COVID-19, support the assumption of heterogeneous and multifaceted pathomechanisms contributing to ICH in COVID-19. Further clinical and pathophysiological investigations are warranted to resolve the conflict between thromboembolic and hemorrhagic complications in the future
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