EDITOR
The aim of the EDITOR project is to carry out industrial research to demonstrate and test the usability and performance of a solar power system designed for continuous operation. The project acronym EDITOR stands for Evaluation of the Dispatchability of a Parabolic Trough Collector System with Concrete Storage.
The system consists of a medium-sized parabolic trough collector circuit in combination with a thermal concrete storage unit and is experimentally designed for industrial applications that require heating or cooling for up to 24 hours. In general, the solar energy system can provide heating or cooling for 24 hours at the consumer's request.
The project partners were in favour of setting up the solar plant in the Republic of Cyprus, as the country has excellent solar resources.
The current market for solar collectors designed for process heating applications is dominated by systems with maximum operating temperatures of around 250 °C. While these collectors are capable of effectively generating process steam, few of them are equipped with any form of storage. Larger solar collectors designed to power electricity generation plants have been equipped with complex molten salt storage systems and can operate at higher temperatures, but these often use thermal oils as heat transfer media, which are classified as toxic and harmful.
Project
In the EDITOR project, for the first time in the history of the development of parabolic trough collectors, the thermal oil used will be operated at a temperature of over 400 °C. This is made possible by the use of a new environmentally friendly thermal oil based on silicone. This is made possible by the use of a new environmentally friendly silicone-based thermal oil, with which the operating temperature can be increased to 425 °C. Another innovation is the use of a newly developed evacuated heat collecting element (i.e. a receiver tube). The heat collecting element was specially designed for the medium parabolic trough collector aperture to increase the efficiency of the collector. To be able to produce energy on demand, an innovative new concrete storage system will be used and tested. The three-year project not only covers the technical activities of building, commissioning and operating the solar power plant. It also involves commercial considerations such as the feasibility of scaling up, identifying future customers and communicating this important development to the potential market.
The EDITOR team consists of five partners from three countries, all with the specific solar industry experience needed to make the project a success. The project partners are:
- Protarget AG (Cologne, Germany)
- CADE Soluciones de Ingeniería, S. L. (Albacete, Spain)
- Cyprus University of Technology (Limassol, Cyprus)
- German Aerospace Center (Cologne, Germany)
- Solar Institute Jülich of the FH Aachen (Jülich, Germany)
The project duration is from 1.10.2015 - 30.11.2019 for the Solar Institute Jülich and from 1.10.2015 - 31.8.2019 for all other partners.
The project partners would like to express their sincere thanks for the public funding received so far for carrying out the industrial research. The international EDITOR project is funded by the Research Promotion Foundation (RPF) from Cyprus, the Ministry of Economy and Competitiveness (MINECO) from Spain, the Federal Ministry for Economic Affairs and Energy (BMWi) from Germany and the Ministry of Innovation, Science and Research of the State of North Rhine-Westphalia from Germany. SOLAR-ERA.NET, a European network bringing together funding organisations, is supported by the European Commission within the EU Framework Programme for Research and Innovation HORIZON 2020 (Cofund ERA-NET Action, N° 691664 and N°786483).
Responsibilities of the project partners
Protarget AG (address: Zeissstraße 5, 50859 Cologne, Germany):
Protarget is the manufacturer of the parabolic trough collector system. Their main responsibility in the project is the delivery, installation and operation of the PTC system, the coordination of all project partners and the provision of information and data to the research partners for their work packages.
Contact: John Mitchell, mitchellprotarget-ag.com
CADE Soluciones de Ingeniería, S.L. (Address: Parque Científico y Tecnológico, Paseo de la Innovación, 3, 02006 Albacete, Spain):
CADE is the manufacturer of the concrete thermal energy storage system (C-TES). Its main role in the project is to supply and install the concrete thermal energy storage system and to provide information and data to the research partners for their work packages.
Contact: Victor Ruiz, vruizcadesoluciones.com
Cyprus University of Technology (CUT) (Address: 30 Arch. Kyprianos Str., 3041 Limassol, Cyprus):
The Cyprus University of Technology (CUT) is the local partner in the project. Its tasks are, on the one hand, to support project networking in Cyprus and to identify suitable companies on whose premises the solar system can be installed to generate process heat. On the other hand, CUT accompanies the installation of the solar plant and its systems, carries out measurements on site (including mirror reflection) and develops a simulation model of the solar power plant in TRNSYS to carry out annual yield calculations.
Contact: Prof. Soteris Kalogirou, soteris.kalogiroucut.ac.cy
German Aerospace Center (Deutsches Zentrum für Luft- und Raumfahrt e. V .) (address: Linder Höhe, 51147 Cologne):
The main task of the German Aerospace Center (DLR) in the project is to monitor the performance of the heat transfer medium (physical-chemical properties, ageing behaviour and high-temperature stability) and to simulate the operation of the enclosure in an autoclave laboratory experiment in order to assess the thermal stress on the HTF performance under reference conditions. In addition, DLR will investigate the components in contact with the heat transfer medium.
Contact: Dr Christian Jung, Christian.Jungdlr.de
Solar Institute Jülich (address: Heinrich-Mussmann-Str. 5, 52428 Jülich, Germany):
The main tasks of the Solar Institute Jülich (SIJ) are the installation of a weather station at the site of the solar power plant, the provision (loan) of a reflectometer to CUT to carry out specular reflectance measurements and the creation of a simulation model that accurately replicates the real solar power plant. The simulation model will be used, among other things, to improve the control of the PTC plant, to simulate adapted operating strategies before they are implemented in the process control system of the real enclosure, and to make accurate predictions about the energy yield and efficiency of the enclosure when it is scaled up.
Contact: Prof. Dr.-Ing. Spiros Alexopoulos, [email protected]
Identification of a process heat consumer in Cyprus
At the beginning of the project, the local project partner Cyprus University of Technology identified several potential companies in the Republic of Cyprus that need process heat. In general, the solar system can be used by any consumer (e.g. food and beverage industry, hotels, etc.) that needs some form of heating or cooling and has a large enough area to install the system. After site visits in Cyprus, the beverage company KEAN Soft Drinks Ltd in Limassol was selected to install the solar power system on their premises. The exact location of the solar power system at KEAN Soft Drinks Ltd is: 34.691618N, 33.075022E (34°41'29.8 "N 33°04'30.1 "E) The address is: KEAN Soft Drinks Ltd Agios Athanasios Limassol Cyprus
Solar resources of Cyprus and status of fossil fuel dependence
Cyprus is an island in the Mediterranean Sea and is the southernmost member of the European Union after Malta when comparing the location of its capitals. The geographical coordinates of the Cypriot capital Nicosia are approximately 35.18°N 33.38°E. The city of Limassol, in the south of Cyprus, is the southernmost city in the European Union (34.69°N 33.07°E). [1] Cyprus has excellent resources of direct normal irradiance (DNI) of up to 2200 kWh/m2 (average value for the period 1994-2016) and is therefore an ideal country for the implementation of an industrial research project in the field of concentrating solar thermal technology.
The climate in Cyprus is very dry in summer. In the hottest months - July and August - the daytime temperature in the central plain can rise up to 36 °C. In the summer months, rainfall is almost negligible. However, thunderstorms occasionally form during this time, accounting for up to 5% of the total annual precipitation. [3]
In the summer months, the daily hours of sunshine in Cyprus are very long. On the longest day of the year (21 June) the sunshine duration is 14h20min. On the shortest day of the year (21 December) the sun shines for 9h40min.
Cyprus is very dependent on fossil fuels. As the country has neither its own oil fields nor oil refineries, it imports all its oil. Most of its electricity is generated in oil-fired power plants. A small amount of electricity comes from solar (photovoltaic), wind, geothermal enclosures and biomass energy sources. [4]
Heat generation from renewable energy sources is dominated by solar thermal enclosures. In 2016, a total of 2,926 TJ of heat was generated from these enclosures alone. Only 65 TJ and 186 TJ were generated from geothermal and biomass plants, respectively, in the same year. [4]
Bibliography:
[1] https://solargis.com
[2] https://solargis.com
[3] http://www.moa.gov.cy/moa/ms/ms.nsf/DMLcyclimate_en/DMLcyclimate_en?OpenDocument
[4] http://www.mof.gov.cy/mof/cystat/statistics.nsf/All/A6EB39CA3885F8ABC22582030022CF1F/$file/ABSTRACT-2016-EN-271217.pdf?OpenElement
Design of solar power plants
First, KEAN's manufacturing processes were thoroughly investigated to determine the most appropriate technical implementation of the solar energy system. KEAN uses a fossil-fired boiler to generate saturated steam (188°C, 11 barg) for the pasteurisation process just before the juice is filled into cartons or bottles. The solar energy system designed in EDITOR generates up to 5% of KEAN's saturated steam demand, resulting in lower fossil fuel consumption.
The main components of the enclosure are listed below:
- double-row PTC field with a total length of 96 m
- two-module concrete heat storage tank
- boiler
- thermal oil pump
The PTC's aperture of 3 m falls into the category of medium-sized collectors. This necessitated the development of a new type of heat collection element (HCE), the diameter of which is specially adapted to the collector aperture in order to maximise the collector's efficiency. In addition, the enclosure uses a newly developed thermal oil called HELISOL XA, which can be heated up to 425 °C. The C-TES has a capacity of 1,000 kWh. The C-TES has a capacity of 600 kWh and enables a demand-based and continuous supply of steam.
