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AbstractFlugzeuganprall wird als außergewöhnliche Einwirkung für stark exponierte kritische Infrastrukturen wie Kernkraftwerke oder sehr große Hochhäuser in Betracht gezogen. Der Beitrag stellt die Entwicklung und Validierung neuer Bauwerkskonzepte auf Basis von Hochleistungsbetonen (HPC, UHPC) vor. Als Beispiele dienen ein Hochhaus [1, 2] und ein externes Schutzbauwerk für bestehende Kernkraftwerke [3, 4], bei denen jeweils der Einsatz von Hochleistungsbetonen die Entwicklung innovativer Tragwerke ermöglicht. Die Methoden des Zwei‐Massen‐Schwingers (ZMS) und Finite‐Elemente‐Methoden in der Struktur‐ und Kurzzeitdynamik werden zusammen mit publizierten und eigenen Validierungsexperimenten [5, 6] benützt, um die Grenzdicke (ultra‐)hochfester, faserbewehrter Stahlbetonbauteile zu ermitteln und somit zentrale Sicherheitszonen der Gebäude vor Brand und Trümmerflug zu schützen.Innovative critical infrastucture with high performance concrete: design against aircraft impactAircraft impact is taken into account as exceptional load case for exposed critical infrastructure such as nuclear plants and super‐rise buildings. This contribution introduces the development and validation of new building concepts based on high performance concretes (HPC, UHPC). A high‐rise building [1, 2] and a superstructure for existing nuclear power plants [2, 3] serve as examples with high performance concretes allowing innovative designs. The design methods “Two‐Degree‐of‐Freedom Model” (TDOF, in German ZMS) and Finite Element Methods for transient and structural dynamics are used together with own validation experiments [5, 6] to derive the limit thicknesses of (ultra) high performance concrete elements with fiber reinforcement, protecting the vital zones of the buildings against impact and fire.

AbstractFlugzeuganprall wird als außergewöhnliche Einwirkung für stark exponierte kritische Infrastrukturen wie Kernkraftwerke oder sehr große Hochhäuser in Betracht gezogen. Der Beitrag stellt die Entwicklung und Validierung neuer Bauwerkskonzepte auf Basis von Hochleistungsbetonen (HPC, UHPC) vor. Als Beispiele dienen ein Hochhaus [1, 2] und ein externes Schutzbauwerk für bestehende Kernkraftwerke [3, 4], bei denen jeweils der Einsatz von Hochleistungsbetonen die Entwicklung innovativer Tragwerke ermöglicht. Die Methoden des Zwei‐Massen‐Schwingers (ZMS) und Finite‐Elemente‐Methoden in der Struktur‐ und Kurzzeitdynamik werden zusammen mit publizierten und eigenen Validierungsexperimenten [5, 6] benützt, um die Grenzdicke (ultra‐)hochfester, faserbewehrter Stahlbetonbauteile zu ermitteln und somit zentrale Sicherheitszonen der Gebäude vor Brand und Trümmerflug zu schützen.Innovative critical infrastucture with high performance concrete: design against aircraft impactAircraft impact is taken into account as exceptional load case for exposed critical infrastructure such as nuclear plants and super‐rise buildings. This contribution introduces the development and validation of new building concepts based on high performance concretes (HPC, UHPC). A high‐rise building [1, 2] and a superstructure for existing nuclear power plants [2, 3] serve as examples with high performance concretes allowing innovative designs. The design methods “Two‐Degree‐of‐Freedom Model” (TDOF, in German ZMS) and Finite Element Methods for transient and structural dynamics are used together with own validation experiments [5, 6] to derive the limit thicknesses of (ultra) high performance concrete elements with fiber reinforcement, protecting the vital zones of the buildings against impact and fire.

Increasing energy efficiency is discussed as an effective way to protect the climate, even though this is frequently associated with additional (investment) costs when compared to standard technologies. However, the investment costs of emerging energy-efficient technologies can be reduced by economies of scale and experience curve effects. This also brings about higher market penetration by lowering market barriers. Experience curves have already been analyzed in detail for renewable energy technologies, but are not as well documented for energy-efficient technologies despite their significance for energy and climate policy decisions. This work provides empirical evidence for effects of economies of scale and experience on the costs of energy-efficient electric motors. We apply a new methodology to the estimation of learning effects that is particularly promising for energy-efficient technologies where the very low data availability did not allow calculations of learning rates so far. Energy-efficient electric motors are a highly relevant energy technology that is responsible for about 55% of German electricity consumption. The analysis consists of three main steps. First, the calculation of composite price indices based on gross value added statistics for Germany which show the changes in cost components of electric motors over the period 1995 to 2006; second, an estimation of the corresponding learning rate which is, in a third step, compared with learning rates observed for other energy-efficient technologies in a literature review. Due to restrictions of data availability, it was not possible to calculate a learning rate for the differential costs of energy-efficient motors compared to standard motors. Still, we estimated a learning rate of 9% for “Eff2” motors in a period when they penetrated the market and replaced the less efficient “Eff3” motors. Furthermore, we showed the contribution of different effects to these cost reductions, like a reduction of material use per motor produced by 15% and an improvement of labor productivity of 43%.

Increasing energy efficiency is discussed as an effective way to protect the climate, even though this is frequently associated with additional (investment) costs when compared to standard technologies. However, the investment costs of emerging energy-efficient technologies can be reduced by economies of scale and experience curve effects. This also brings about higher market penetration by lowering market barriers. Experience curves have already been analyzed in detail for renewable energy technologies, but are not as well documented for energy-efficient technologies despite their significance for energy and climate policy decisions. This work provides empirical evidence for effects of economies of scale and experience on the costs of energy-efficient electric motors. We apply a new methodology to the estimation of learning effects that is particularly promising for energy-efficient technologies where the very low data availability did not allow calculations of learning rates so far. Energy-efficient electric motors are a highly relevant energy technology that is responsible for about 55% of German electricity consumption. The analysis consists of three main steps. First, the calculation of composite price indices based on gross value added statistics for Germany which show the changes in cost components of electric motors over the period 1995 to 2006; second, an estimation of the corresponding learning rate which is, in a third step, compared with learning rates observed for other energy-efficient technologies in a literature review. Due to restrictions of data availability, it was not possible to calculate a learning rate for the differential costs of energy-efficient motors compared to standard motors. Still, we estimated a learning rate of 9% for “Eff2” motors in a period when they penetrated the market and replaced the less efficient “Eff3” motors. Furthermore, we showed the contribution of different effects to these cost reductions, like a reduction of material use per motor produced by 15% and an improvement of labor productivity of 43%.

The paper reports on the methodology and results of several studies on the long-term efficiency potentials in the two energy transformation steps from primary energy to final and useful energy and, more importantly, from useful energy to energy services. The examination of these potentials considers the lifetimes and periods of refurbishment of manufactured artefacts: Buildings and infrastructure that will save or waste energy in 2050 that are being built or restored today. The paper emphasises the enormous size of energy conservation potentials achievable not only by reducing energy losses but also by decreasing the specific activity levels for several energy services through improved material efficiency and intensified use of products, plants, and vehicles. It also reports on major definitive conclusions on R&D needs and challenges to R&D-policies as well as immediate policy action in OECD-countries in order to realise the vision of reducing primary energy use per capita by two thirds in industrialised countries within the next five decades.

The paper reports on the methodology and results of several studies on the long-term efficiency potentials in the two energy transformation steps from primary energy to final and useful energy and, more importantly, from useful energy to energy services. The examination of these potentials considers the lifetimes and periods of refurbishment of manufactured artefacts: Buildings and infrastructure that will save or waste energy in 2050 that are being built or restored today. The paper emphasises the enormous size of energy conservation potentials achievable not only by reducing energy losses but also by decreasing the specific activity levels for several energy services through improved material efficiency and intensified use of products, plants, and vehicles. It also reports on major definitive conclusions on R&D needs and challenges to R&D-policies as well as immediate policy action in OECD-countries in order to realise the vision of reducing primary energy use per capita by two thirds in industrialised countries within the next five decades.

AbstractConsolidated tables showing an extensive listing of the highest independently confirmed efficiencies for solar cells and modules are presented. Guidelines for inclusion of results into these tables are outlined and new entries since January, 2009 are reviewed. Copyright © 2009 John Wiley & Sons, Ltd.

AbstractConsolidated tables showing an extensive listing of the highest independently confirmed efficiencies for solar cells and modules are presented. Guidelines for inclusion of results into these tables are outlined and new entries since January, 2009 are reviewed. Copyright © 2009 John Wiley & Sons, Ltd.