Sub-project 1:
Development of a cost-effective parabolic trough collector and interconnection with systems for decentralized electricity and cooling generation
Sub-project 2:
Development of a thermally driven refrigeration system with low to medium output and high COP
Joint research project: Component development for highly efficient decentralized solar-assisted combined heat and power generation
Objectives
The aim of the joint research project is to develop a combined heat, power and cooling plant system for the use of solar process heat, which is supplied via a parabolic trough collector at a temperature level of 250°C. The load-oriented coordination of the components with each other in an integral plant system is the prerequisite for the efficient and economical use of energy. The sustainable technology is at the beginning of its development.
In principle, the individual system components are available on the market. An integral system for solar combined heat, power and cooling in a capacity range suitable for decentralized use is not yet available. In contrast to the existing solar thermal power plants (>50 MWel), the development is aimed at plant sizes from 500 kWel to 5 MWel and thus occupies a market that enables the implementation of decentralized supply systems.
The project partners TU Braunschweig, Ostfalia University of Applied Sciences and Mithras are working on the development part of solar thermal energy and solar thermal power generation. The Institute of Air Handling and Refrigeration Technology and Wegra are working on the development part of highly efficient thermal refrigeration.
The research project is being carried out as a joint project. This results in the following sub-projects:
Development of a cost-effective parabolic trough collector and interconnection with systems for decentralized electricity and refrigeration generation
Development of a thermally driven refrigeration system with low to medium output and high COP
The project is being coordinated by the Institute for Building and Solar Technology at TU Braunschweig. Direct project partners are the TU Braunschweig (IGS) and the ILK Dresden. Subcontractors of TU Braunschweig for subproject 1 "CS collector for solar CHP" are Mithras Anlagenbau from Dersum and Ostfalia University, subcontractors of ILK Dresden for subproject 2 "HE solar chiller" are Wegra Anlagenbau from Westenfeld.
Aim of sub-project 1
As part of the joint project, the first sub-project aims to develop a cost-effective solar collector for process heat generation (parabolic trough), which can be used to provide heat at a higher temperature level of around 250°C for decentralized power generation and thermal cooling. In the field of electricity generation, a range of 0.5 to a maximum of 5 MWel is targeted. This is not large-scale solar thermal power technology (> 50 MWel) but decentralized supply systems for the small and medium power range.
A prototype system consisting of 12 modules with a total mirror surface area of 138 m² is to be built within the project and made available for measurements on the test stand in Dersum. A parabolic trough module consists of 4 mirrors with a total surface area of 11.5 m², with one mirror having a surface area of 2.875 m² (height 2.3 m, width 1.25 m).
The Tesla turbine developed by Mithras Anlagenbau GmbH in parallel with the research project will be installed on the test stand in Dersum together with the chiller developed in sub-project 2 and integrated into an overall system for solar thermal electricity and cooling generation via the parabolic trough collector and measured. These investigations will initially serve to coordinate the overall system with regard to the supplementary power supply. In the first stage, the technical implementation of the system is planned to focus on the provision of solar process heat and cooling.
Aim of sub-project 2
The aim is to develop, build and test a thermally driven refrigeration system, preferably a double-effect absorption refrigeration system with the working material pair water-lithium bromide, for the highly efficient use of solar heat in the low power range.
The system should have a high conversion efficiency of heating energy into cooling energy. It should have a compact design and consequently integrate innovative heat exchangers of small sizes. After testing and measuring the cooling system, it is to be connected to the solar combined heat and power plant within the joint research project.
Overall objective of the project
The overall objective of the project is the development, implementation and testing of a combined system consisting of the high-temperature collectors and a highly efficient thermally driven refrigeration system in the low output range (approx. 50 kW), preferably for a two-stage absorption chiller (working material pair H2O / LiBr).
As part of the joint project, the prerequisites for the construction of a modular, decentralized energy network system for the solar-supported provision of heat, cooling and electricity in the small and medium power range are to be created.