19 research outputs found

    Scope of Electricity Efficiency Improvement in Switzerland until 2035

    Get PDF
    This study uses Markowitz mean-variance portfolio theory with forecasted data for the years 2005 to 2035 to determine efficient electricity generating technology mixes for Switzerland. The SURE procedure has been applied to filter out the systematic components of the covariance matrix. Results indicate that risk-averse electricity users in 2035 gain in terms of higher expected return, less risk, more security of supply and a higher return-to-risk ratio compared to 2000 by adopting a feasible minimum variance (MV) technology mix containing 28 percent Gas, 20 percent Run of river, 13 percent Storage hydro, 9 percent Nuclear, and 5 percent each of Solar, Smallhydro, Wind, Biomass, Incineration, and Biogas respectively. However, this mix comes at the cost of higher CO2 emissions.Efficiency Frontier, Herfindahl-Hirschman Index (HH), Power Generation, Mean-Variance Portfolio Theory, Seemingly Unrelated Regression Estimations (SURE), Shannon-Wiener Index (SW)

    Efficient Electricity Portfolios for Switzerland and the United States

    Get PDF
    This study applies financial portfolio theory to determine efficient electricity-generating technology mixes for Switzerland and the United States. Expected returns are given by the (negative of the) rate of increase of power generation cost. Volatility of returns relates to the standard deviation of the cost increase associated with the portfolio, which contains Nuclear, Run of river, Storage hydro and Solar in the case of Switzerland, and Coal, Nuclear, Gas, Oil, and Wind in the case of the United States. Since shocks in generation costs are found to be correlated, the seemingly unrelated regression estimation (SURE) method is applied for filtering out the systematic component of the covariance matrix of the cost changes. Results suggest that at observed generation costs in 2003, the maximum expected return (MER) portfolio for Switzerland would call for a shift towards Nuclear and Solar, and therefore away from Run of river and Storage hydro. By way of contrast, the minimum variance (MV) portfolio mainly contains Nuclear power and Storage hydro. The 2003 MER portfolio for the United States contains Coal generated electricity and Wind, while the MV alternative combines Coal, Nuclear, Oil and Wind. Interestingly, Gas does not play any role in the determination of efficient electricity portfolios in the United States.energy, electricity, portfolio theory, efficiency frontier, seemingly unrelated regression estimations (SURE)

    Efficient provision of electricity for the United States and Switzerland

    Get PDF
    This study applies financial portfolio theory to determine efficient frontiers in the provision of electricity for the United States and Switzerland. Expected returns are defined by the rate of productivity increase of power generation (adjusted for external costs), volatility, by its standard deviation. Since unobserved productivity shocks are found to be correlated, Seemingly Unrelated Regression Estimation (SURE) is used to filter out the systematic component of the covariance matrix of the productivity changes. Results suggest that as of 2003, the feasible maximum expected return (MER) electricity portfolio for the United States contains more Coal, Nuclear, and Wind than actual but markedly less Gas and Oil. The minimum variance (MV) portfolio contains markedly more Oil, again more Coal, Nuclear, and Wind but almost no Gas. Regardless of the choice between MER and MV, U.S. utilities are found to lie substantially inside the efficient frontier. This is even more true of their Swiss counterparts, likely due to continuing regulation of electricity markets.Efficiency frontier, energy, electricity, portfolio theory, Seemingly Unrelated Regression Estimation (SURE)

    The impact of liberalization on the scope of efficiency improvement in electricity-generating portfolios for the United States and Switzerland

    Get PDF
    Zusammenfassung: In dieser Studie werden effiziente Portfolien nach Markowitz fĂŒr die USA und der Schweiz berechnet. Dabei wird die Sicht eines Investors (fĂŒr den die Rendite der VerĂ€nderung der gewonnen kWh/USD entspricht) der Sicht des laufenden Benutzers (fĂŒr den die Rendite den kWh/USD selbst entspricht) gegenĂŒbergestellt. De zwischen den Schocks, die auf die Stromerzeugungskosten einwirken, Korrelationen bestehen, wird das SURE (Seemingly Unrelated Regression Estimation) Verfahren angewendet, um eine ĂŒber die Zeit stabile Kovarianzmatrix zu erhalten. Das tatsĂ€chliche Technologieportfolio der USA liegt dichter an der Effizienzgrenze als dasjenige der Schweiz. Ein möglicher Grund hierfĂŒr ist die Energiemarktliberalisierung, die in den USA deutlich weiter vorangeschritten ist als in der Schwei

    The comorbidity profiles and medication issues of patients with multiple system atrophy:a systematic cross-sectional analysis

    Get PDF
    BACKGROUND: Multiple system atrophy (MSA) is a complex and fatal neurodegenerative movement disorder. Understanding the comorbidities and drug therapy is crucial for MSA patients' safety and management.OBJECTIVES: To investigate the pattern of comorbidities and aspects of drug therapy in MSA patients.METHODS: Cross-sectional data of MSA patients according to Gilman et al. (2008) diagnostic criteria and control patients without neurodegenerative diseases (non-ND) were collected from German, multicenter cohorts. The prevalence of comorbidities according to WHO ICD-10 classification and drugs administered according to WHO ATC system were analyzed. Potential drug-drug interactions were identified using AiDKlinikÂź.RESULTS: The analysis included 254 MSA and 363 age- and sex-matched non-ND control patients. MSA patients exhibited a significantly higher burden of comorbidities, in particular diseases of the genitourinary system. Also, more medications were prescribed MSA patients, resulting in a higher prevalence of polypharmacy. Importantly, the risk of potential drug-drug interactions, including severe interactions and contraindicated combinations, was elevated in MSA patients. When comparing MSA-P and MSA-C subtypes, MSA-P patients suffered more frequently from diseases of the genitourinary system and diseases of the musculoskeletal system and connective tissue.CONCLUSIONS: MSA patients face a substantial burden of comorbidities, notably in the genitourinary system. This, coupled with increased polypharmacy and potential drug interactions, highlights the complexity of managing MSA patients. Clinicians should carefully consider these factors when devising treatment strategies for MSA patients.</p

    The comorbidity and co-medication profile of patients with progressive supranuclear palsy

    Get PDF
    BackgroundProgressive supranuclear palsy (PSP) is usually diagnosed in elderly. Currently, little is known about comorbidities and the co-medication in these patients.ObjectivesTo explore the pattern of comorbidities and co-medication in PSP patients according to the known different phenotypes and in comparison with patients without neurodegenerative disease.MethodsCross-sectional data of PSP and patients without neurodegenerative diseases (non-ND) were collected from three German multicenter observational studies (DescribePSP, ProPSP and DANCER). The prevalence of comorbidities according to WHO ICD-10 classification and the prevalence of drugs administered according to WHO ATC system were analyzed. Potential drug-drug interactions were evaluated using AiDKlinik (R).ResultsIn total, 335 PSP and 275 non-ND patients were included in this analysis. The prevalence of diseases of the circulatory and the nervous system was higher in PSP at first level of ICD-10. Dorsopathies, diabetes mellitus, other nutritional deficiencies and polyneuropathies were more frequent in PSP at second level of ICD-10. In particular, the summed prevalence of cardiovascular and cerebrovascular diseases was higher in PSP patients. More drugs were administered in the PSP group leading to a greater percentage of patients with polypharmacy. Accordingly, the prevalence of potential drug-drug interactions was higher in PSP patients, especially severe and moderate interactions.ConclusionsPSP patients possess a characteristic profile of comorbidities, particularly diabetes and cardiovascular diseases. The eminent burden of comorbidities and resulting polypharmacy should be carefully considered when treating PSP patients

    Scope of Electricity Efficiency Improvement in Switzerland until 2035

    Full text link
    This study uses Markowitz mean-variance portfolio theory with forecasted data for the years 2005 to 2035 to determine efficient electricity generating technology mixes for Switzerland. The SURE procedure has been applied to filter out the systematic components of the covariance matrix. Results indicate that risk-averse electricity users in 2035 gain in terms of higher expected return, less risk, more security of supply and a higher return-to-risk ratio compared to 2000 by adopting a feasible minimum variance (MV) technology mix containing 28 percent Gas, 20 percent Run of river, 13 percent Storage hydro, 9 percent Nuclear, and 5 percent each of Solar, Smallhydro, Wind, Biomass, Incineration, and Biogas respectively. However, this mix comes at the cost of higher CO2 emissions

    Efficient and secure power for the United States and Switzerland

    Full text link
    In this contribution, portfolio theory is applied to power technologies of the United States and Switzerland. A current user view is adopted to determine the efficient frontier of generation technologies in terms of expected return and risk. Since shocks in generation costs per kWh (the inverse of expected returns) are correlated, seemingly unrelated regression estimation (SURE) is applied to filter out the systematic components of the covariance matrix. Since some of the portfolios of particular interest (minimum variance, maximum expected return) call for a high share of one technology, security of supply becomes an issue. Shannon-Wiener and Herfindahl-Hirschman indices are calculated to see the trade-off between efficiency and security of supply. Results suggest that riskaverse utilities (and ultimately, consumers) in the United States would have gained from adopting a feasible portfolio containing more coal, gas and oil at a price of a somewhat reduced security of supply. In the case of Switzerland, the realistic portfolio consists of nuclear, storage hydro, run of river and solar, with shares identical to those of the actual portfolio in 2003. Therefore, the current mix of Swiss generating technologies in Switzerland may be deemed efficient

    Efficient Electricity Portfolios for Switzerland and the United States

    Full text link
    This study applies financial portfolio theory to determine efficient electricity-generating technology mixes for Switzerland and the United States. Expected returns are given by the (negative of the) rate of increase of power generation cost. Volatility of returns relates to the standard deviation of the cost increase associated with the portfolio, which contains Nuclear, Run of river, Storage hydro and Solar in the case of Switzerland, and Coal, Nuclear, Gas, Oil, and Wind in the case of the United States. Since shocks in generation costs are found to be correlated, the seemingly unrelated regression estimation (SURE) method is applied for filtering out the systematic component of the covariance matrix of the cost changes. Results suggest that at observed generation costs in 2003, the maximum expected return (MER) portfolio for Switzerland would call for a shift towards Nuclear and Solar, and therefore away from Run of river and Storage hydro. By way of contrast, the minimum variance (MV) portfolio mainly contains Nuclear power and Storage hydro. The 2003 MER portfolio for the United States contains Coal generated electricity and Wind, while the MV alternative combines Coal, Nuclear, Oil and Wind. Interestingly, Gas does not play any role in the determination of efficient electricity portfolios in the United States

    Efficient Electricity Portfolios for the United States and Switzerland: An Investor View

    Full text link
    This study applies financial portfolio theory to determine efficient electricity-generating technology portfolios for the United States and Switzerland, adopting an investor point of view. Expected returns are defined by the rate of decrease of power generation cost (with external costs included), their volatility, by its standard deviation. The 2003 portfolio contains Coal, Nuclear, Gas, Oil, and Wind in the case of the United States, and Nuclear, Storage hydro, Run of river, and Solar in the case of Switzerland, a country without domestic supplies of fossil fuels. Since shocks in generation costs are found to be correlated, Seemingly Unrelated Regression Estimation (SURE) is used to filter out the systematic component of the covariance matrix of the cost changes. Results suggest that as of 2003, the feasible maximum expected return (MER) electricity portfolio for the United States contains more Coal, Nuclear, and Wind than actual but markedly less Gas and Oil. By way of contrast, the minimum variance (MV) portfolio combines markedly more Oil, Coal, Nuclear, and Wind but almost no Gas. Therefore, regardless of the choice between MER and MV, U.S. utilities as investors are substantially inside the efficient frontier. This is even more true of their Swiss counterparts, likely due to continuing regulation of electricity markets
    corecore