Ralf Dott | University of Applied Sciences and Arts FHNW, Switzerland (original) (raw)

Papers by Ralf Dott

Journal of Energy Storage

Im Rahmen des europäischen ERACOBUILD-Programms war es im internationalen Forschungsprojekt <e... more Im Rahmen des europäischen ERACOBUILD-Programms war es im internationalen Forschungsprojekt <em>SchoolVentCool </em>das Ziel, die Energieeffizienz, die Raumluft- als auch und Tageslichtqualität bei bestehenden Schulgebäuden zu verbessern. Dies soll mit der Anwendung von vorfabrizierten Fassaden-Modulen mit integrierter Lüftungstechnik erreicht werden. Im Forschungsprojekt CCEM-Advanced Retrofit wurden gemeinsam mit Industriepartnern und Handwerksbetrieben Lösungen für vorfabrizierte Fassadenmodule mit integrierten Lüftungsleitungen für zu erneuernde Mehrfamilienhäuser entwickelt. In SchoolVentCool wurden mit Hilfe der dort gemachten Erfahrungen die Lösungen auf Schulgebäude übertragen. Der höhere, flächenspezifische Frischluftbedarf in Schulgebäuden hat eine einschneidende Auswirkung auf die fassadenintegrierten Lüftungsleitungen und in Folge auch auf die Architektur. Es war notwendig, mit dem System dezentraler Frischluftversorgung einen weiteren, ergänzenden Lösungsweg...

Energy Procedia, 2012

Combined solar and heat pump systems have a large potential to reduce CO 2 and other emissions fr... more Combined solar and heat pump systems have a large potential to reduce CO 2 and other emissions from the sector of domestic hot water preparation and space heating. Subtask C of the IEA SHC Task 44 / HPP Annex 38 deals with modeling and simulation of these systems. A review of component models for the simulation of combined solar and heat pump heating systems has been carried out with a special focus on the particularities of the combination of solar thermal collectors with heat pumps. Some of these particularities are effects of water vapor condensation on the surface of collector absorbers operated below the dew point, refrigeration cycles using more than one heat exchanger for the evaporator in order to use solar heat in addition to a conventional heat source, the effect of higher source temperature for the heat pump when solar heat is used, or the regeneration of ground heat sources with heat from solar collectors.

The International Energy Agency (IEA) is an autonomous body within the framework of the Organizat... more The International Energy Agency (IEA) is an autonomous body within the framework of the Organization for Economic Co-operation and Development (OECD) based in Paris. Established in 1974 after the first “oil shock, ” the IEA is committed to carrying out a comprehensive program of energy cooperation among its members and the Commission of the European Communities. The IEA provides a legal framework, through IEA Implementing Agreements such as the Solar Heating and Cooling Agreement, for international collaboration in energy technology research and development (R&D) and deployment. This IEA experience has proved that such collaboration contributes significantly to faster technological progress, while reducing costs; to eliminating technological risks and duplication of efforts; and to creating numerous other benefits, such as swifter expansion of the knowledge base and easier harmonization of standards. The Solar Heating and Cooling Programme was one of the first IEA Implementing Agree...

IEA Solar Heating and Cooling Programme The International Energy Agency (IEA) is an autonomous bo... more IEA Solar Heating and Cooling Programme The International Energy Agency (IEA) is an autonomous body within the framework of the Organization for Economic Co-operation and Development (OECD) based in Paris. Established in 1974 after the first “oil shock, ” the IEA is committed to carrying out a comprehensive program of energy cooperation among its members and the Commission of the European Communities. The IEA provides a legal framework, through IEA Implementing Agreements such as the Solar Heating and Cooling Agreement, for international collaboration in energy technology research and development (R&D) and deployment. This IEA experience has proved that such collaboration contributes significantly to faster technological progress, while reducing costs; to eliminating technological risks and duplication of efforts; and to creating numerous other benefits, such as swifter expansion of the knowledge base and easier harmonization of standards. The Solar Heating and Cooling Programme was...

Low energy houses are seen as a key technology for the reduction of CO2-emissions and have growin... more Low energy houses are seen as a key technology for the reduction of CO2-emissions and have growing market shares in many countries. Residential heat pumps have increasing market shares in new buildings, as well, particularly in low energy buildings. However, there are still development potentials for existing system solutions in terms of component and system performance as well as system integration and func-tionality. IEA HPP Annex 32 is to accomplish research to explore the promising market of heat pump solutions for low energy houses. This paper gives an introduction to the Annex 32 framework of object-tives, project structures and national contributions. First results of the Swiss national project, which is dedicated to the integration of passive and active cooling functions, yielded a standardised hydronic con-figuration of ground-coupled heat pumps for space heating,-cooling and domestic hot water, which sim-plifies the variety of marketable configurations. Design guidelines f...

The energy demand for heating decreases in highly-insulated dwellings. Comfort cooling becomes mo... more The energy demand for heating decreases in highly-insulated dwellings. Comfort cooling becomes more important due to higher thermal loads and rising summer thermal comfort demands. Heat pumps can provide space heat and domestic hot water but also may provide cooling. Heat sources of heat pumps often can be used for passive cooling. The aim of the project is to support energy efficient solutions for heating and cooling of residential buildings. First step should always be reducing the heat loads by e.g. shading and night-time ventilation. In a simulation study three heat pump systems have been compared, a variable refrigerant flow multi-split air-to-air heat pump, an air-to-water heat pump and a brine-to-water heat pump. The system with vertical borehole heat exchanger yields the highest efficiency in all modes. Only few additional components are necessary to add the cooling function. The air- to-water heat pump shows the lowest efficiency but also lowest additional system expenditur...

Economic, energetic and environmental concerns foster the development of clean and efficient solu... more Economic, energetic and environmental concerns foster the development of clean and efficient solutions for residential energy systems. Combined heat and power (CHP) systems allow covering the heat and electricity demand simultaneously. Micro-CHP systems are expected to spread in building application during next years. Thus, finding an optimal size and configuration between micro-CHP, PV module and battery could help to improve the energy saving potential of such systems. The goal of the study is to identify and understand the influence of some key parameters like PV size, CHP power or battery size on CHP/PV system eco-energetic profitability in residential application with focus on the interactions between components. A parametric study is performed to find an optimal trade-off between objective functions like electricity selfsufficiency, electricity self-usage, CO2 impact or costs. The heating system of the building is modelled and simulated in a Simulink/Carnot model and analysed....

Journal of Energy Storage

Im Rahmen des europäischen ERACOBUILD-Programms war es im internationalen Forschungsprojekt <e... more Im Rahmen des europäischen ERACOBUILD-Programms war es im internationalen Forschungsprojekt <em>SchoolVentCool </em>das Ziel, die Energieeffizienz, die Raumluft- als auch und Tageslichtqualität bei bestehenden Schulgebäuden zu verbessern. Dies soll mit der Anwendung von vorfabrizierten Fassaden-Modulen mit integrierter Lüftungstechnik erreicht werden. Im Forschungsprojekt CCEM-Advanced Retrofit wurden gemeinsam mit Industriepartnern und Handwerksbetrieben Lösungen für vorfabrizierte Fassadenmodule mit integrierten Lüftungsleitungen für zu erneuernde Mehrfamilienhäuser entwickelt. In SchoolVentCool wurden mit Hilfe der dort gemachten Erfahrungen die Lösungen auf Schulgebäude übertragen. Der höhere, flächenspezifische Frischluftbedarf in Schulgebäuden hat eine einschneidende Auswirkung auf die fassadenintegrierten Lüftungsleitungen und in Folge auch auf die Architektur. Es war notwendig, mit dem System dezentraler Frischluftversorgung einen weiteren, ergänzenden Lösungsweg...

Energy Procedia, 2012

Combined solar and heat pump systems have a large potential to reduce CO 2 and other emissions fr... more Combined solar and heat pump systems have a large potential to reduce CO 2 and other emissions from the sector of domestic hot water preparation and space heating. Subtask C of the IEA SHC Task 44 / HPP Annex 38 deals with modeling and simulation of these systems. A review of component models for the simulation of combined solar and heat pump heating systems has been carried out with a special focus on the particularities of the combination of solar thermal collectors with heat pumps. Some of these particularities are effects of water vapor condensation on the surface of collector absorbers operated below the dew point, refrigeration cycles using more than one heat exchanger for the evaporator in order to use solar heat in addition to a conventional heat source, the effect of higher source temperature for the heat pump when solar heat is used, or the regeneration of ground heat sources with heat from solar collectors.

The International Energy Agency (IEA) is an autonomous body within the framework of the Organizat... more The International Energy Agency (IEA) is an autonomous body within the framework of the Organization for Economic Co-operation and Development (OECD) based in Paris. Established in 1974 after the first “oil shock, ” the IEA is committed to carrying out a comprehensive program of energy cooperation among its members and the Commission of the European Communities. The IEA provides a legal framework, through IEA Implementing Agreements such as the Solar Heating and Cooling Agreement, for international collaboration in energy technology research and development (R&D) and deployment. This IEA experience has proved that such collaboration contributes significantly to faster technological progress, while reducing costs; to eliminating technological risks and duplication of efforts; and to creating numerous other benefits, such as swifter expansion of the knowledge base and easier harmonization of standards. The Solar Heating and Cooling Programme was one of the first IEA Implementing Agree...

IEA Solar Heating and Cooling Programme The International Energy Agency (IEA) is an autonomous bo... more IEA Solar Heating and Cooling Programme The International Energy Agency (IEA) is an autonomous body within the framework of the Organization for Economic Co-operation and Development (OECD) based in Paris. Established in 1974 after the first “oil shock, ” the IEA is committed to carrying out a comprehensive program of energy cooperation among its members and the Commission of the European Communities. The IEA provides a legal framework, through IEA Implementing Agreements such as the Solar Heating and Cooling Agreement, for international collaboration in energy technology research and development (R&D) and deployment. This IEA experience has proved that such collaboration contributes significantly to faster technological progress, while reducing costs; to eliminating technological risks and duplication of efforts; and to creating numerous other benefits, such as swifter expansion of the knowledge base and easier harmonization of standards. The Solar Heating and Cooling Programme was...

Low energy houses are seen as a key technology for the reduction of CO2-emissions and have growin... more Low energy houses are seen as a key technology for the reduction of CO2-emissions and have growing market shares in many countries. Residential heat pumps have increasing market shares in new buildings, as well, particularly in low energy buildings. However, there are still development potentials for existing system solutions in terms of component and system performance as well as system integration and func-tionality. IEA HPP Annex 32 is to accomplish research to explore the promising market of heat pump solutions for low energy houses. This paper gives an introduction to the Annex 32 framework of object-tives, project structures and national contributions. First results of the Swiss national project, which is dedicated to the integration of passive and active cooling functions, yielded a standardised hydronic con-figuration of ground-coupled heat pumps for space heating,-cooling and domestic hot water, which sim-plifies the variety of marketable configurations. Design guidelines f...

The energy demand for heating decreases in highly-insulated dwellings. Comfort cooling becomes mo... more The energy demand for heating decreases in highly-insulated dwellings. Comfort cooling becomes more important due to higher thermal loads and rising summer thermal comfort demands. Heat pumps can provide space heat and domestic hot water but also may provide cooling. Heat sources of heat pumps often can be used for passive cooling. The aim of the project is to support energy efficient solutions for heating and cooling of residential buildings. First step should always be reducing the heat loads by e.g. shading and night-time ventilation. In a simulation study three heat pump systems have been compared, a variable refrigerant flow multi-split air-to-air heat pump, an air-to-water heat pump and a brine-to-water heat pump. The system with vertical borehole heat exchanger yields the highest efficiency in all modes. Only few additional components are necessary to add the cooling function. The air- to-water heat pump shows the lowest efficiency but also lowest additional system expenditur...

Economic, energetic and environmental concerns foster the development of clean and efficient solu... more Economic, energetic and environmental concerns foster the development of clean and efficient solutions for residential energy systems. Combined heat and power (CHP) systems allow covering the heat and electricity demand simultaneously. Micro-CHP systems are expected to spread in building application during next years. Thus, finding an optimal size and configuration between micro-CHP, PV module and battery could help to improve the energy saving potential of such systems. The goal of the study is to identify and understand the influence of some key parameters like PV size, CHP power or battery size on CHP/PV system eco-energetic profitability in residential application with focus on the interactions between components. A parametric study is performed to find an optimal trade-off between objective functions like electricity selfsufficiency, electricity self-usage, CO2 impact or costs. The heating system of the building is modelled and simulated in a Simulink/Carnot model and analysed....