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Optimization models can support decision-makers in the synthesis and operation of multi-sector energy systems. To identify the optimal design and operation of a low-carbon system, we need to consider high temporal and spatial variability in the electricity supply, sector coupling, and environmental impacts over the whole life cycle. Incorporating such aspects in optimization models is demanding. To avoid redundant research efforts and enhance transparency, the developed models and used data sets should be shared openly. In this work, we present the SecMOD framework for multi-sector energy system optimization incorporating life-cycle assessment (LCA). The framework allows optimizing multiple sectors jointly, ranging from industrial production and their linked energy supply systems to sector-coupled national energy systems. The framework incorporates LCA to account for environmental impacts. We hence provide the first open-source framework to consistently include a holistic life-cycle perspective in multi-sector optimization by a full integration of LCA. We apply the framework to a case-study of the German sector-coupled energy system. Starting with few base technologies, we demonstrate the modular capabilities of SecMOD by the stepwise addition of technologies, sectors and existing infrastructure. Our modular open-source framework SecMOD aims to accelerate research for sustainable energy systems by combining multi-sector energy system optimization and life-cycle assessment.

Optimization models can support decision-makers in the synthesis and operation of multi-sector energy systems. To identify the optimal design and operation of a low-carbon system, we need to consider high temporal and spatial variability in the electricity supply, sector coupling, and environmental impacts over the whole life cycle. Incorporating such aspects in optimization models is demanding. To avoid redundant research efforts and enhance transparency, the developed models and used data sets should be shared openly. In this work, we present the SecMOD framework for multi-sector energy system optimization incorporating life-cycle assessment (LCA). The framework allows optimizing multiple sectors jointly, ranging from industrial production and their linked energy supply systems to sector-coupled national energy systems. The framework incorporates LCA to account for environmental impacts. We hence provide the first open-source framework to consistently include a holistic life-cycle perspective in multi-sector optimization by a full integration of LCA. We apply the framework to a case-study of the German sector-coupled energy system. Starting with few base technologies, we demonstrate the modular capabilities of SecMOD by the stepwise addition of technologies, sectors and existing infrastructure. Our modular open-source framework SecMOD aims to accelerate research for sustainable energy systems by combining multi-sector energy system optimization and life-cycle assessment.

Research in the field of precision agriculture is becoming increasingly important due to the growing world population whilst area for cultivation remains constant or declines. In this context, methods of monitoring in?season plant development with high resolution and accuracy are necessary. Studies show that terrestrial laser scanning (TLS) can be applied to capture small objects like crops. In this contribution, the results of multi-temporal field campaigns with the terrestrial laser scanner Riegl LMS-Z420i are shown. Four surveys were carried out in the growing period 2012 on a field experiment where various barley varieties were cultivated in small-scale plots. In order to measure the plant height above ground, the TLS-derived point clouds are interpolated to generate Crop Surface Models with a very high resolution of 1 cm. For all campaigns, a common reference surface, representing the Digital Elevation Model was used to monitor plant height in the investigated period. Manual plant height measurements were carried out to verify the results. The very high coefficients of determination (R² = 0.89) between both measurement methods show the applicability of the approach presented. Furthermore, destructive biomass sampling was performed to investigate the relation to plant height. Biomass is an important parameter for evaluating the actual crop status, but non-destructive methods of directly measuring crop biomass do not exist. Hence, other parameters like reflectance are considered. The focus of this study is on non-destructive measurements of plant height. The high coefficients of determination between plant height and fresh as well as dry biomass (R² = 0.80, R² = 0.77) support the usability of plant height as a predictor. The study presented here demonstrates the applicability of TLS in monitoring plant height development with a very high spatial resolution. Proceedings of the Workshop on UAV-based Remote Sensing Methods for Monitoring Vegetation Kölner geographische Arbeiten, 94 ISSN:0454-1294

Research in the field of precision agriculture is becoming increasingly important due to the growing world population whilst area for cultivation remains constant or declines. In this context, methods of monitoring in?season plant development with high resolution and accuracy are necessary. Studies show that terrestrial laser scanning (TLS) can be applied to capture small objects like crops. In this contribution, the results of multi-temporal field campaigns with the terrestrial laser scanner Riegl LMS-Z420i are shown. Four surveys were carried out in the growing period 2012 on a field experiment where various barley varieties were cultivated in small-scale plots. In order to measure the plant height above ground, the TLS-derived point clouds are interpolated to generate Crop Surface Models with a very high resolution of 1 cm. For all campaigns, a common reference surface, representing the Digital Elevation Model was used to monitor plant height in the investigated period. Manual plant height measurements were carried out to verify the results. The very high coefficients of determination (R² = 0.89) between both measurement methods show the applicability of the approach presented. Furthermore, destructive biomass sampling was performed to investigate the relation to plant height. Biomass is an important parameter for evaluating the actual crop status, but non-destructive methods of directly measuring crop biomass do not exist. Hence, other parameters like reflectance are considered. The focus of this study is on non-destructive measurements of plant height. The high coefficients of determination between plant height and fresh as well as dry biomass (R² = 0.80, R² = 0.77) support the usability of plant height as a predictor. The study presented here demonstrates the applicability of TLS in monitoring plant height development with a very high spatial resolution. Proceedings of the Workshop on UAV-based Remote Sensing Methods for Monitoring Vegetation Kölner geographische Arbeiten, 94 ISSN:0454-1294

To satisfy the increasingly stringent emission regulations and a demand for an ever lower fuel consumption, diesel engines have become complex systems with many interacting actuators. As a consequence, these requirements are pushing control and calibration to their limits. The calibration procedure nowadays is still based mainly on engineering experience, which results in a highly iterative process to derive a complete engine calibration. Moreover, automatic tools are available only for stationary operation, to obtain control maps that are optimal with respect to some predefined objective function. Therefore, the exploitation of any leftover potential during transient operation is crucial. This paper proposes an approach to derive a transient feedforward (FF) control system in an automated way. It relies on optimal control theory to solve a dynamic optimization problem for fast transients. A partially physics-based model is thereby used to replace the engine. From the optimal solutions, the relevant information is extracted and stored in maps spanned by the engine speed and the torque gradient. These maps complement the static control maps by accounting for the dynamic behavior of the engine. The procedure is implemented on a real engine and experimental results are presented along with the development of the methodology.

To satisfy the increasingly stringent emission regulations and a demand for an ever lower fuel consumption, diesel engines have become complex systems with many interacting actuators. As a consequence, these requirements are pushing control and calibration to their limits. The calibration procedure nowadays is still based mainly on engineering experience, which results in a highly iterative process to derive a complete engine calibration. Moreover, automatic tools are available only for stationary operation, to obtain control maps that are optimal with respect to some predefined objective function. Therefore, the exploitation of any leftover potential during transient operation is crucial. This paper proposes an approach to derive a transient feedforward (FF) control system in an automated way. It relies on optimal control theory to solve a dynamic optimization problem for fast transients. A partially physics-based model is thereby used to replace the engine. From the optimal solutions, the relevant information is extracted and stored in maps spanned by the engine speed and the torque gradient. These maps complement the static control maps by accounting for the dynamic behavior of the engine. The procedure is implemented on a real engine and experimental results are presented along with the development of the methodology.

Improved resource efficiency in the construction industry is needed to balance sustainability requirements with growing demand for new infrastructure. Resource efficiency includes the reduction of primary and non-renewable materials, the creation of high-quality products with minimal waste, and the retention of long-term product value. One potential source of resource efficiency is the increased adoption of industrialized housing construction which includes novel construction methods and products. Current literature identifies numerous opportunities for resource efficiency in industrialized housing construction. However, this literature is scattered across several sources and units of analysis. Using a Systematic Literature Review, this paper identifies eight recurrent product and process-related themes and fifteen specific subthemes of resource efficiency in industrialized housing construction across building lifecycle phases. These themes can be based on product such as the use of innovative and industrial materials or on process such as the use of inventory monitoring and tracking. Additional industry and regulatory themes are also identified. Furthermore using frequency analysis of literature, the paper finds while themes of resource efficiency exist across all building lifecycle phases, the most recurring themes occur in design, manufacturing and logistics phases. There is less literature dedicated to resource efficiency during occupancy and end-of-life phases. The paper further discusses how early design decisions such as material design have a systems-level impact that propagates throughout the building lifecycle, and how a beyond-systems approach is needed between stakeholders and processes to integrate current resource efficiency potentials into industrialized housing construction practice. Finally, the paper identifies future research directions for resource-efficient industrialized housing construction including concepts of circular economy, value chain coordination, and socio-economic impacts. Journal of Cleaner Production, 286 ISSN:0959-6526