Refine
Year of publication
Institute
- Solar-Institut Jülich (37) (remove)
Has Fulltext
- no (37)
Document Type
- Conference Proceeding (32)
- Part of a Book (3)
- Article (2)
Keywords
- Energy storage (4)
- Power plants (4)
- Associated liquids (3)
- Concentrated solar power (3)
- Hybrid energy system (3)
- Central receiver power plant (2)
- Concentrated systems (2)
- Electricity generation (2)
- Gas turbine (2)
- Solar thermal technologies (2)
- Camera system (1)
- Ceramics (1)
- Cloud passages (1)
- Concentrating solar power (1)
- Control optimization (1)
- DNI forecast (1)
- DNI forecasting (1)
- Decision theory (1)
- Direct normal irradiance forecast (1)
- Dynamic simulation (1)
- Electrochemistry (1)
- Fresnel power plant (1)
- Global change (1)
- Heliostat Field Calibration (1)
- Heliostats (1)
- Hybridization (1)
- Measuring instruments (1)
- Molten salt receiver (1)
- Molten salt receiver system (1)
- Molten salt receiver system, (1)
- Molten salt solar tower (1)
- Nowcasting (1)
- PTC (1)
- Parabolic trough collector (1)
- Photovoltaics (1)
- Power conversion systems (1)
- Process prediction (1)
- Quadrocopter (1)
- Solar irradiance (1)
- Star design (1)
- Thermal Energy Storage (1)
- Transient flux distribution (1)
- Two-phase modelling (1)
- UAV (1)
- Uncertainty analysis (1)
- Unmanned aerial vehicle (1)
Is part of the Bibliography
- no (37)
The Solar-Institut Jülich (SIJ) and the companies Hilger GmbH and Heliokon GmbH from Germany have developed a small-scale cost-effective heliostat, called “micro heliostat”. Micro heliostats can be deployed in small-scale concentrated solar power (CSP) plants to concentrate the sun's radiation for electricity generation, space or domestic water heating or industrial process heat. In contrast to conventional heliostats, the special feature of a micro heliostat is that it consists of dozens of parallel-moving, interconnected, rotatable mirror facets. The mirror facets array is fixed inside a box-shaped module and is protected from weathering and wind forces by a transparent glass cover. The choice of the building materials for the box, tracking mechanism and mirrors is largely dependent on the selected production process and the intended application of the micro heliostat. Special attention was paid to the material of the tracking mechanism as this has a direct influence on the accuracy of the micro heliostat. The choice of materials for the mirror support structure and the tracking mechanism is made in favor of plastic molded parts. A qualification assessment method has been developed by the SIJ in which a 3D laser scanner is used in combination with a coordinate measuring machine (CMM). For the validation of this assessment method, a single mirror facet was scanned and the slope deviation was computed.
This work presents a basic forecast tool for predicting direct normal irradiance (DNI) in hourly resolution, which the Solar-Institut Jülich (SIJ) is developing within a research project. The DNI forecast data shall be used for a parabolic trough collector (PTC) system with a concrete thermal energy storage (C-TES) located at the company KEAN Soft Drinks Ltd in Limassol, Cyprus. On a daily basis, 24-hour DNI prediction data in hourly resolution shall be automatically produced using free or very low-cost weather forecast data as input. The purpose of the DNI forecast tool is to automatically transfer the DNI forecast data on a daily basis to a main control unit (MCU). The MCU automatically makes a smart decision on the operation mode of the PTC system such as steam production mode and/or C-TES charging mode. The DNI forecast tool was evaluated using historical data of measured DNI from an on-site weather station, which was compared to the DNI forecast data. The DNI forecast tool was tested using data from 56 days between January and March 2022, which included days with a strong variation in DNI due to cloud passages. For the evaluation of the DNI forecast reliability, three categories were created and the forecast data was sorted accordingly. The result was that the DNI forecast tool has a reliability of 71.4 % based on the tested days. The result fulfils SIJ’s aim to achieve a reliability of around 70 %, but SIJ aims to still improve the DNI forecast quality.
As part of the transnational research project EDITOR, a parabolic trough collector system (PTC) with concrete thermal energy storage (C-TES) was installed and commissioned in Limassol, Cyprus. The system is located on the premises of the beverage manufacturer KEAN Soft Drinks Ltd. and its function is to supply process steam for the factory's pasteurisation process [1]. Depending on the factory's seasonally varying capacity for beverage production, the solar system delivers between 5 and 25 % of the total steam demand. In combination with the C-TES, the solar plant can supply process steam on demand before sunrise or after sunset. Furthermore, the C-TES compensates the PTC during the day in fluctuating weather conditions. The parabolic trough collector as well as the control and oil handling unit is designed and manufactured by Protarget AG, Germany. The C-TES is designed and produced by CADE Soluciones de Ingeniería, S.L., Spain. In the focus of this paper is the description of the operational experience with the PTC, C-TES and boiler during the commissioning and operation phase. Additionally, innovative optimisation measures are presented.