The Noor Ouarzazate III concentrated solar power (CSP) plant, part of the largest solar complex on Earth, is already in service in Ouarzazate, Morocco, and almost ready to enter commercial operation. Rated at 150 MW, it differs from two adjacent plants, Noor Ouarzazate I and Noor Ouarzazate II, already in operation, thanks to its novel technology: Noor Ouarzazate III uses a power tower with molten salt storage, and is the biggest operational plant in the world in this configuration. It is also the second power tower with molten salt storage that has been designed and constructed by SENER using its own technology, as the company built on the success of the pioneering Gemasolar plant, which has been operating at full power in Seville (Spain) since 2011.
Due to its size and notable technological advances, the entry into commercial operation of Noor Ouarzazate III is sparking the interest of the world's energy sector by once again putting forward (as Gemasolar did seven years ago) the power tower and molten salt storage technology as a cutting-edge engineering solution for developers of CSP plants. The high production capacity of this design, in which the molten salt reach a higher temperature than in other CSP configurations, maximizes thermodynamic efficiency and allows managing the solar energy in the absence of direct sunlight in response to peaks in demand. This unique characteristic of thermoelectric solar energy, which is absent from other energy sources like photovoltaic or wind energy, substantially alters the role of renewable energies in supplying the world's electricity.
Noor Ouarzazate III offers significant innovations. In fact, many of engineering advances that SENER has applied to Noor Ouarzazate III are the result of a major R&D effort previously undertaken by the company. For example, the high-temperature receiver - with SENER covering the entire cycle from design to manufacture, start-up, operation and maintenance - stems from an advanced design for a 600 MWt receiver, the prototype for which was manufactured and tested by the technical team at SENER. Likewise, the storage system uses tanks that are similar in size to those used at the Termosol plant in Spain. Since Noor Ouarzazate III requires maximum output during times of peak demand, which in Morocco occurs at sunset, the manageability of the plant was a top design priority. Thanks to the 7.5 hours of thermal storage available at the plant, the output has been optimized such that electricity can be supplied to the grid during these hours of greatest demand. Lastly, at Noor Ouarzazate III SENER used one of its new, patented HE54 heliostats, with a larger reflective area than in the heliostats installed in Gemasolar. A prototype of this heliostat - consisting of a hydraulic mechanism and pre-fabricated and pre-stressed concrete pylons - has been in use at the plant in Seville for two years, where constant testing has confirmed its expected performance. Finally, the Sensol simulation tool, developed by SENER, was used to make accurate predictions of the facility's electricity production.
The combination of new components and the application of economies of scale to their industrial production was key to reducing the cost of the electricity. SENER also incorporated improvements identified in other solar plants (which translated into the technological developments mentioned above), leading to increased efficiency. For example, the integrated control system developed by SENER, which connects the receiver and the 7,400-heliostat solar field, offers peak levels of operation.
In addition, as part of the turnkey consortium that built Noor Ouarzazate III, SENER is responsible for the conceptual, basic and detail engineering, as well as for supplying the equipment and for the future operation and maintenance of the facility. As a result, part of the improvement process involved integrating all the components and efficiently managing the supply chain, which relied heavily on local Moroccan companies; this circumstance has allowed developing a local business network with high added value.
SENER resolved the challenge of managing the supply chain, which was particularly complex in this project, by setting up a sound and reliable relationship with its suppliers. At Noor Ouarzazate III, SENER used local suppliers, SENER's usual suppliers in Spain and new suppliers from Asia. This coordination was logistically challenging, involving everything from managing delivery times to payment methods, tariffs and fluctuating raw material prices.
Thanks to this, SENER was able to handle very large volumes of materials and components, which had to be delivered on very tight timelines. The overall figures for the facility are as follows: a total assembly and storage area of 150,000 sqm, more than two million sqm of reflective area, 58,000 tons of steel and 48 daily truck deliveries.
In short, Noor Ouarzazate III represents, for both SENER and the CSP sector, a consolidation of the power tower, heliostat field and molten salt storage technology. Once it enters commercial operation, it will be a benchmark for future solar energy plants built all over the world.
The solar field at Noor Ouarzazate III has 7,400 HE54 heliostats (designed and patented by SENER), which use a highly accurate solar tracker system, also patented by the company, to redirect the sunlight to a receiver located high atop a 250-m tower. The solar radiation, in the form of heat, is focused on a high-power, 600+ MWt receiver, designed by SENER and built in concert with Moroccan companies. Noor Ouarzazate III also features a molten salt storage system that is used to preserve excess energy so that the plant can continue producing electricity for up to 7.5 hours in the absence of sunlight. This way, the plant makes it possible to manage (or dispatch) the energy.
Noor Ouarzazate III is part of the Noor solar complex, the largest on the planet, located in Ouarzazate (Morocco) and promoted by Morocco's solar power agency, MASEN, a state-owned company that, through this visionary investment in solar power, has ensured a clean, sustainable and safe electricity supply for Morocco. In this mega-project, SENER is part of the turnkey construction consortium of the Noor Ourzazate I and Noor Ouarzazate II plants, both of which rely on SENERtrough® cylindrical-parabolic trough technology, and Noor Ouarzazate III, with its power tower and molten salt storage technology.
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