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Der “Unterbau”, die Infrastruktursysteme – sie haben für die Entwicklung einer Gesellschaft selbst sowie für deren wirtschaftliche Entwicklung eine oft unterschätzte Bedeutung. Sie sind sehr langlebig und stellen eine enorme Investition dar. Einmal getroffene Entscheidungen (etwa über “eingesetzte” Technologien, Kapaziäiten) binden die Gesellschaft langfristig. Die Nachwirkungen beeinflussen auch die Handlungsoptionen nachfolgender Generationen. Neben den finanziellen Aspekten sind vor allem Aspekte der Ressourceneffizienz einmal gewählter Infrastruktur-Technologien in Betracht zu ziehen. Die starke Abhängigkeit vom eingeschlagenen Pfad führt zur Inflexibilität derartiger Systeme und kann somit zu einem Hemmnis für den technischen Fortschritt und die Wettbewerbsfähigkeit einer Gesellschaft werden. Dies gilt vor allem für leitungsgebundene Infrastruktursysteme (Wasser, Abwasser, Strom, Gas et cetera), ganz besonders dann, wenn sie unterirdisch verlegt und darum schlecht zugänglich sind. Im folgenden soll exemplarisch auf Abwasserentsorgungseinrichtungen eingegangen werden, die zu den ältesten Infrastruktursystemen gehören. Gerade im Bereich der Abwasserentsorgung sind die bestehenden Einrichtungen in einem zum Teil desolaten Zustand; in Deutschland stehen zur Sanierung der Systeme derzeit Re-Investitionen an, die auf die Größenordnung von mindestens 100–150 Milliarden DEM geschätzt werden. Die Handlungsfähigkeit der Akteure wird damit für Jahrzehnte eingeschränkt werden. Die Tatsache, daß hier mittelfristig ein beträchtlicher Investitionsbedarf besteht, sollte dazu genutzt werden, vorhandene Abwasserentsorgungs-Konzepte nicht unreflektiert fortzuschreiben, sondern sie vor dem Hintergrund der aktuellen umweltpolitischen Paradigmen (Ressourceneffizienz, Nachhaltigkeit) kritisch zu prüfen und gegebenenfalls einen technologischen Systemwechsel anzustoßen. Abstarct & Keywords → p. 238

Abstract The goal of the project “Smart Region Pellworm” is the establishment and operation of a smart grid with a hybrid energy storage system on the German island of Pellworm.One part of the project is the integration of power-to-heat appliances into the smart grid for demand side management purposes.Thispaper deals with the prerequisites and lessons learned from the integration of electric night storage heaters into Pellworm's energy management system. Special focus lies on the development of a heat demand prediction model.

In order to achieve long-term targets for energy savings and emission reductions, substantial savings will be needed from existing buildings. For example, a recent analysis for the USA examines aggressive strategies to cut carbon emissions in half by 2040 and finds that in order to achieve this emission reduction target, more than half of existing buildings will need comprehensive energy efficiency retrofits. Germany is targeting an overall primary energy consumption reduction of 50% in 2050 including increasing building renovation rate to 2% per year. In France, ambitious targets have also been set for existing buildings: 50% reduction of primary energy consumption in 2050 compared to the 2012 level. Multiple countries have realized the importance of comprehensive building retrofits and have begun to adopt policies to spur these improvements. For example, Germany is emphasizing grants and loans through the KfW Development Bank, complemented with building and heating system labels, a new ""heating check"" programme, and possible technical renovation requirements. France has established a goal of bringing all buildings up to ""A"" performance level (on their A-G scale) by 2050 in order for them to be sold or leased, with lower performance levels required as soon as 2020. In the USA, the focus has been on a combination of rating and disclosure of energy use, financing, and technical assistance. Focused community approaches show promise. This paper summarizes the efforts, successes and challenges, future directions, and savings of building retrofit policies in the three countries. We conclude by contrasting the three countries and discussing areas of opportunity for these and other countries.

This paper presents a toolset for the efficient control of the indoor air quality and thermal comfort in retrofitted buildings. The refurbishment of existing buildings, compliant to actual regulations, often leads to airtightness and the consequent poor conditions for the occupants that could cause low productivity and even sickness. For this reason, the CETIEB (Cost Effective Tools for Better Indoor Environment in Retrofitted Energy Efficient Buildings) project developed innovative low-cost solutions to monitor and control the indoor air quality and thermal comfort. Among the technologies developed, this paper presents ad-hoc sensors for the monitoring of Total Volatile Organic Components (TVOC), CO2 and thermal comfort together with a control logic that, using measured data, provides the optimal rules to actuate the control devices (ventilation, heating/cooling, windows opening, shutters operation and so on). The application and validation of the integrated solution, monitoring plus control logic, was performed in a laboratory building to compare the performance of the proposed solution with the traditional system employed in buildings. The results turned out to show sensors performances comparable with commercial solutions but with a significant reduction of costs. Moreover, the application of the integrated solution showed an improvement of the indoor air quality and comfort with a 15% of energy saving, compared to the traditional thermostatic control.

Lebensdaueruntersuchung geschweißter Aluminiumverbindungen mittels energiebasierten Kriterien bei kombinierter Biegung und Torsion. Im vorliegenden Beitrag werden Berechnungen zur Lebensdauer von Aluminiumschweißverbindungen (Rohr-Rohr- und Rohr-Flansch-Verbindungen) unter reiner Biegung und unter einer Kombination von Biegung mit Torsion vorgestellt und mit experimentellen Ergebnisse verglichen. Um den multiachsialen Beanspruchungszustand auf eine uniachsiale Belastung zu reduzieren, wurde ein enregiebasiertes Kriterium in der kritischen Ebene angewendet. Die besten Ergebnisse wurden erzielt, indem das Kriterium der maximalen Scher-Verformungsenergiedichte in der kritischen Ebene genutzt wurde, um die äquivalente lokale Spannungsamplitude für die Rohr-Rohr-Schweißungen zu berechnen, und zwar für beides, proportionale und nicht-proportionale Biegung mit Torsion. Für die Rohr-Flansch-Verbindungen unter proportionaler und nicht-proportionaler Biegung mit Torsion wurden die besten Resultate erreicht, indem das Kriterium der maximalen Scherung und der Normaldehnungsenergiedichte angewendet wurde.

Implementing “first-time-right” production processes increases a production line’s sustainability and minimizes rejects. Multi-camera systems are a key element since they can quickly detect defects without contact. However, it is still a time-consuming challenge to determine the correct number and position of cameras to achieve gapless surface monitoring of complex components. This proposal aims to develop a new software tool that automatically calculates and visualizes surface coverage by using bipolar plates as an example. With this method, 100% surface coverage inspections become feasible, and the cost of commissioning multi-camera inspection systems can be significantly decreased.

The field of energy forecasting has attracted many researchers from different fields (e.g., meteorology, data sciences, mechanical or electrical engineering) over the last decade. Solar forecasting is a fast-growing subdomain of energy forecasting. Despite several previous attempts, the methods and measures used for verification of deterministic (also known as single-valued or point) solar forecasts are still far from being standardized, making forecast analysis and comparison difficult. To analyze and compare solar forecasts, the well-established Murphy–Winkler framework for distribution-oriented forecast verification is recommended as a standard practice. This framework examines aspects of forecast quality, such as reliability, resolution, association, or discrimination, and analyzes the joint distribution of forecasts and observations, which contains all time-independent information relevant to verification. To verify forecasts, one can use any graphical display or mathematical/statistical measure to provide insights and summarize the aspects of forecast quality. The majority of graphical methods and accuracy measures known to solar forecasters are specific methods under this general framework. Additionally, measuring the overall skillfulness of forecasters is also of general interest. The use of the root mean square error (RMSE) skill score based on the optimal convex combination of climatology and persistence methods is highly recommended. By standardizing the accuracy measure and reference forecasting method, the RMSE skill score allows—with appropriate caveats—comparison of forecasts made using different models, across different locations and time periods. Refereed/Peer-reviewed

The main obstacles in preliminary design studies or optimization of jacket substructures for offshore wind turbines are high numerical expenses for structural code checks and simplistic cost assumptions. In order to create a basis for fast design evaluations, this work provides the following: first, a jacket model is proposed that covers topology and tube sizing with a limited set of design variables. Second, a cost model is proposed that goes beyond the simple and common mass-dependent approach. And third, the issue of numerical efficiency is addressed by surrogate models for both fatigue and ultimate limit state code checks. In addition, this work shows an example utilizing all models. The outcome can be utilized for preliminary design studies and jacket optimization schemes. It is suitable for scientific and industrial applications.

The aim of the System Dynamics Model for Economic Assessment of Sustainability Policies of Transport (ESCOT) is to describe a path towards a sustainable transport system in Germany and to assess its economic impacts. ESCOT was developed within the environmentally sustainable transport (EST) project of the Organization for Economic Co?operation and Development (OECD) that was designed to set up the ecological and technical framework of a transition towards sustainable transportation. ESCOT comprises five models: macroeconomic, transport, regional economic, environmental and policy. The economic assessment for environmentally sustainable scenarios shows that the departure from car? and road freight?oriented transport policy is far from leading to an economic breakdown. By expanding the period for the transition, even more encouraging economic results were derived. For the economic assessment, it is important that ESCOT considers not only first round effects, but also secondary effects. This ability makes ESCOT a powerful instrument for the assessment of such large system transitions.

Abstract Engineers are confronted with difficulties when it comes to the inclusion of sustainability aspects into the design process of electronic devices. Due to the specific nature and complexity of material composition, process flows and data availability there is a need for electronics-specific methodologies for environmental assessment. These need to allow for easy adaptation in all stages of the design process thus leading to a rapid identification of critical hotspots in system design. To fulfil this demand, indicators available for product-level assessment are evaluated with regard to environmental impact category coverage, practicability and significance for selected application fields of electronics. Case studies on sensor nodes and lighting products are used to show the application of indicator sets in industrial settings. As an outcome, indicator sets are identified that support the designer in keeping track of the overall sustainability of electronic products.