NEXTOWER, the new project in concentrated solar power coordinated by ENEA

Two prototypes under construction in Italy and Spain with new ultra-resistant materials for solar towers and thermal storage


Developing ultra-resistant materials and innovative technologies for energy storage to improve performance, life cycle and competitiveness of concentrated solar power plants (CSP). These are the objectives of the European project NEXTOWER [1], coordinated by ENEA and winner of the international “CEN-CENELEC Standards + Innovation Award 2020”.


18 leading companies and research institutions in Europe are involved: at national level, in addition to ENEA, Consortium CALEF, Certimac, Walter Tosto, Sapienza University of Rome and Turin Polytechnic; at foreign level: The Chancellor, Masters and Scholars of The University Of Oxford (United Kingdom), KTH Royal Institute of Technology and Sandvik Materials Technology (Sweden), EngiCer (Switzerland), Siltronix (France), Liqtech (Germany), beWarrant ( Belgium), CIEMAT, ICAMCYL, R2M and the regulatory body UNE (Spain).
“Over 20 researchers from three ENEA departments are involved in this project, which aims at achieving a pioneering technological horizon for concentrated solar power. In addition, the processes, solutions and technologies implemented will have significant applications in numerous energy production sectors, including those storing or using CO2 and IV generation nuclear power, ” Antonio Rinaldi, coordinator of the project and researcher at the ENEA Sustainability Department of Productive and Territorial Systems explained.

As part of the project, two prototypes will be constructed: SOLEAD # 1 at the Plataforma Solar De Almeria (PSA) of CIEMAT, in Spain; SOLEAD # 2 at the ENEA Brasimone Center (Bologna), in the Tuscan-Emilian Apennines.

SOLEAD # 1, aimed at studying solar air receivers made with two types of highly thermally conductive ceramic materials, capable of withstanding temperatures of 1,100 ° C. The receivers will be mounted 80 meters high in the large 7 MW concentrated solar power plant. The innovations developed in NEXTOWER aim at raising the temperature of the air leaving the receiver up to 900 ° C, allowing the combination with hybrid gas turbines, much more flexible, or the production of process heat for industrial plants, in the future .

SOLEAD # 2 in Brasimone will be dedicated to the study of high temperature thermal storage operating with liquid lead: a system conceived and designed by ENEA thanks to its long standing expertise and know-how in the design and management of liquid metal facilities for cooling nuclear reactors and thermal storage systems for thermodynamic solar plants, and the collaboration of industrial partners also involved in the supply of materials, such as the Swedish Kanthal, and in the construction of components, like the Italian Walter Tosto.

The 100kW prototype will include an accumulation tank containing approximately 32 tons of lead and two exchangers: a primary one to be combined with the “solar receiver” system and a secondary “heat sink” capable of taking the energy stored to provide process heat or power for electricity production.

“An effort of engineering and manufacturing of excellence that entailed the construction of the tank, the bundles of tubes entirely built with special materials thanks to high value-added industrial processes, as well as the manufacture of the interior coatings of SOLEAD # 2 and the plant interface to the solar receiver, through controlled melting processes of several kms of prototype alloy wire ”, Rinaldi pointed out.

In “central receiver” thermodynamic solar plants, a field of moving mirrors (called heliostats) follows the movement of the sun during the day, always concentrating the sunlight onto a receiver, usually placed on the top of a tower tens to hundreds of meters high.

Inside the receiver, a heat transfer fluid, in this case air, is heated to sufficiently high temperatures withstand the generation of steam necessary to power a turbine for the production of electricity; the heat produced can also be stored in thermal storage systems for on-demand use.




For more information please contact:
Antonio Rinaldi, ENEA- Sustainability of Productive and Territorial Systems Department Email: [email protected]

The award ceremony CEN-CENELEC “Standards + Innovation Awards 2020” can be viewed at:

Project website:

The innovations developed in Nextower published on the European Commission databank : Innovation Radar Platform:

Video of the Plataforma Solar de Almeria

Institutional video Walter Tosto Spa:


Source: ENEA Italian National Agency for New Technologies, Energy and Sustainable Economic Development