Andasol is the first solar thermal complex in the world with heat storage. Andasol, formed by Andasol 1, Andasol I and Andasol II, is located in the Guadix Region in the municipality of Aldeire and La Calahorra, in the province of Granada, Spain. Andasol I, Andasol II and Andasol III, each with 50 MW, have been built on one of the highest and largest plateaus in the Iberian Peninsula (the average height is 1100 m). Thanks to this height it has one of the best direct solar radiation resources in Spain.
Its location near to a 400 kV high voltage line, the availability of water for cooling from the northern slopes of the Sierra Nevada, the nearby road and railway infrastructures and the availability of flat land not protected for environmental reasons, makes it the perfect enclave for the implementation of the solar thermal project.
The most important characteristics are that Andasol III has included better techniques than the two previous ones, which have make it possible to reduce its construction costs, as it uses less land surface, and therefore, less surface of parabolic trough collectors. This optimises its production and efficiency in the electricity production process (from 38.5% of turbines efficiency to 41.2%).
The Andasol Temporary Joint Venture has been in charge of the design and construction of the plant and will also manage its operation. The Temporary Joint Venture is made up of Duro Felguera Energía, Ferrostaal, Solar Millennium and Flagsol.
The Andasol III plant has almost 205,000 parabolic mirrors that capture sunlight. These huge curved mirrors concentrate the heat and transmit it to a heat transfer fluid. Using heat exchangers, the energy is taken to a steam circuit that activates the power generating turbine.
With the integration of a heat storage device, the power generated during the day can be made available to the grid according to the planning. The accumulator contains up to 30,000 tonnes of a special salt compound and has a storage capacity of over seven hours. This allows Andasol III to continue to generate electricity reliably and power the electricity network even at night. Thus, as a whole, the plants can supply electricity, annually, to around half a million people, preventing the emission of 450,000 tonnes of carbon dioxide.
The relevant factor this project has provided is that it is the first thermo-solar project in which a scale prototype has been included, the storage of cold and hot salts in the same tank, called "single-tank". A Research and Development Project headed by the Engineering Firm SENER in which AKO has participated adapting its AKOTRACE® solution to the new requirements of this innovation, demonstrating its high degree of involvement in new technologies, its application in thermoelectric energy and investment in the R&D&i area to be able to prepare studies, field tests and to be able to make technological progress in this type of facilities.
Technical requirements, although already largely resolved by AKO in the dozens of projects implemented in solar thermal power plants with parabolic trough technology.
The scope of the AKO solution has been the execution of the electrical heat-tracing system, AKOTRACE® for the three installations. This project involves AKO in the Solar Thermal Power Plant with the highest production in Europe, consolidating the AKOTRACE® solution as the world leader in the electrical-heat tracing sector. AKO's Innovation Director, Miguel Angel González, referring to this project:"In this project we have improved the control strategies, improving coordination aspects between regulation of the trace circuits to even out the power consumption of the heat-tracing system and we have introduced higher alarm levels to increase the installations safety".
In the AKOTRACE® solution, it is worth mentioning that we have chosen different key technical characteristics for this project:
AKO started the Andasol I and Andasol II Solar Thermal Power Plant project and continued with the same good results obtained in the implementation of the AKOTRACE® solution in Andasol III:
The execution of this project complements the experience and knowledge acquired by AKO throughout its over 30 years of experience, which has positioned it as the world leader, committed to renewable energy future technologies in CSP parabolic trough and concentration tower Solar Thermal Power Plant Projects.
Over 30 years of innovation and with 130 people team of in-house professionals AKO Electromecànica, S.A.L. is a Spanish company leader in the Regulation and Control of Temperature with Electrical Heat Tracing Solutions for Concentrated Solar Power Plants (CSP), that offers comprehensive support from project design and manufacturing, to technical assistance, to the System commissioning (turnkey projects) and after-sales service. Electrical Heat Tracing System AKOTRACE® based the heating cable technology, providing advantages and savings on energy and the overall cost of the installation, with a reliable and secure management, ensuring the health, safety and respect for the environment.