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Renewable Energy Sources

ENEA activities in the field of renewable energy sources are mainly centred upon research, innovation, and technology transfer. The Agency also provides advanced services contributing to both decreasing CO2 emissions and the national energy dependence on fossil sources, and increasing Italy’s economic competitiveness.

In these activities several different Technical Units in different ENEA research centres are involved serving complementary roles to one another: Technical Unit for Renewable Energy Sources (UTRINN – Casaccia), Technical Unit for Portici Technologies (UTTP), and Technical Unit for Trisaia Technologies (UTTT).

Concentrated Solar Thermal Energy

By using parabolic trough collectors, ENEA has developed an innovative technology chain based on a molten salt mixture functioning as heat transfer fluid and thermal storage. Compared with diathermic oil, this technology allows the operating temperature to be increased thus resulting in significant benefits as to the plant’s operation, safety and environmentally-friendly impact. Other considerable advantages derive from the possible integration of this solar plant with the conventional thermoelectric plants and an efficient thermal energy storage, thus increasing the “dispatchability” of the electric power produced against the unpredictability of the solar source.

The first industrial plant powered by the ENEA solar technology has been realized by ENEL in Priolo Gargallo (SR) – under the Archimede Project – and is currently in the demonstration phase.

Based on the expertise and skills matured within the project, currently ENEA is the national referee for the concentrated solar energy technology. The Agency has the ownership of several patents and exclusive skills, and collaborates with a number of companies within several national and international initiatives aimed at enhancing and diffusing this technology. The activities ENEA performs in this field are as follows:

  1. design, development and demonstration of solar power plants for electric power production, cogeneration or water desalination, also integrated with other renewable or fossil sources;
  2. design, building of prototypes, testing, engineering, and qualification of innovative components for solar power plants, especially receiving tubes, solar collectors (supporting structure, reflecting panels, and pointing system), and components of the molten salt circuit (flexible joints, auxiliary heaters, special equipment);
  3. development of new concentrated solar technology applications, including hydrogen production through thermochemical processes and the industrial use of high-temperature thermal energy from the sun.

To carry out these activities ENEA involves a team of 70 researchers and technicians, specific experimental infrastructures (plants and laboratories) located at the Casaccia and Portici research centres, a network of industrial collaborations with over 30 Italian companies, and agreements with several nations interested in building solar plants, including Egypt, Libya, and China.


The principal research activities performed in ENEA in the field of photovoltaics are targeted at making this technology and the field national enterprises competitive by focusing on process and product innovation applied to manufacturing and system technologies, and advanced services to enterprises.

These activities are carried out at the ENEA Portici Research Centres (R&D on thin-film modules, polymeric semiconductor solar cells, flat-plate and concentrating photovoltaic systems), Casaccia Research Centre (R&D on crystalline silicon technologies) and at the research laboratories located in Manfredonia. Manfredonia is the historical test site for large photovoltaic plants, where R&D activities are performed on all system components.

The primary lines of activity are as follows:

  • Design and implementation of photovoltaic devices (crystalline silicon, thin-film silicon, polymers) with morphological, structural, compositional, and electrical characterization of base materials, and optical and electronic modelling of devices;
  • Design and characterization of stand-alone and grid-connected PV components and plants, including the innovative approach for the architectural integration of PV elements in buildings and urban decoration, concentrating plants with design of modules, heliostats and all solar tracker components;
  • Study of plant design solutions for the electrification of isolated or weak-grid communities, with an in-depth examination of the technical problems related to distributed generation and smart grid systems. Telemonitoring for PV plant data transmission.
  • Qualification of photovoltaic modules – complying with the CEI EN 61215 and CEI EN 61646 standards – for a number of stakeholders: manufacturing companies, installers, distributors and/or authorized dealers.
Biomass and Biofuels

Biomass is a plannable energy source, with significant developing forecasts in absolute and relative terms, and its use for energy purposes is a widespread and consolidated reality in our Country.

ENEA activities meet the need to support national industries to provide proper responses to system and technology innovation in the field of electricity and heat generation in small-sized plants (local agro-energetic production chains), and, in prospect, of second-generation biofuels.

With reference to the first issue, current initiatives at Casaccia and Trisaia Research Centres are related to the optimized use of biomass at the territorial level as well as the development, demonstration and qualification of innovative processes, technologies and components for the co-generation of electricity, heat, and/or biofuels at the local level.

Specifically, the initiatives underway are aimed at:

  • producing biogas to be used for electric power generation or in the grid as gas biofuel (biomethane) from codigestion of organic wastes, farm wastes and/or sugar energy crops;
  • exploiting energy from digestate as an alternative to the more traditional use as a farming amendant, by drying and pyrogasification processes, and even by mixing it with lignocellulosic biomass;
  • developing and testing of new technologies for the final use of the produced biogas, such as energy co-generation by combining energy from biogas and fuel cells, with a significant improvement in the final yields of energy conversion and greenhouse gas balance.

R&TD on second-generation biofuels is focused on the possible thermochemical and biochemical conversion processes of lignocellulosic materials such as, respectively, gasification into hydrogen and carbon oxide, and the fermentation of carbohydrates into ethanol, as well as the production of hydrogen from fermentation of humid biomass and biofuels from microalgae cultures.

Those activities relating to the development and testing of processes of lignocellulosic biomass conversion into gas or liquid energy vectors are performed at the Trisaia Research Centre, where several pilot plants have been built which are used for activities within research projects or in support of sector industries.

Particularly, research is carried out on the following subjects:

  • Testing of innovative production chains for ethanol derived from agroforestry biomass and polyannual ligneous and grass biomass cultures;
  • Biomass pretreatment with saturated steam at moderate temperatures (200 °C approximately) aimed at a first separation of its main components (cellulose, hemicellulose, lignine) for its best exploitation into energy or chemical products for food and material industry;
  • Development of second-generation processes for producing ethanol to be used in the transport sector. Such processes are based on highly-efficient and environmentally-friendly pretreatment, enzymatic hydrolysis fermentation, alcohol separation;

R&TD activities relating to energy and biofuel production from cultures of microalgae and other photosynthetic microorganisms are carried out at the Casaccia Research Centre’s Laboratory of microalgae technologies. They include the study, design, implementation and testing of pilot systems and plants, with a view to obtain massive large-scale cultures, particularly targeted at exploitation of all the possible energy and non-energy products and byproducts.

Solar Thermal Energy at low and medium temperatures

The Trisaia Research Centre hosts a plant for the qualification of solar collectors and systems. In this station research is conducted on the applications of low- and medium-temperature solar thermal energy, particularly on the development of flat-plate or concentrating prototypes (CPC systems, parabolic-trough collectors, and Fresnel lens solar concentrators) targeted at heat production for both food thermal processes for civil and industrial applications, and use for innovative helium air-conditioning systems by coupling them with thermal closed-circuit (absorption chiller) or open-circuit devices (DEC systems using solid or liquid drying agents) devices.

Specifically, research is centred on the following activities:

  • Analysis and energy optimization of low and medium temperature solar systems;
  • Development of thermo-fluid-dynamic and optical models for the energy analysis of solar collectors for medium temperature applications; technical and economic evaluation and optimization of solar-cooling plants components;
  • Energetic characterization of CPCs for medium-temperature applications by using test facilities able to thermally analyze such components at an operating temperature of up to 300 °C.

The laboratory is accredited to perform tests in compliance with the EU and International test regulations both for solar collector (EN 12975-2, and ISO 9806), and for solar systems generating sanitary hot water (EN 12976-2, and ISO 9459-2).

Hydrogen, Fuel Cells and Energy Storage Systems

ENEA activities in this field are generally aimed at contributing to the development of energy vectors and electrochemical systems for energy conversion and storage. Such systems can reduce energy consumption and emissions in the distributed energy and transport sectors, thus encouraging the latter to benefit from the use of renewables.
The R&D lines of activity are mainly:

  • Development of processes producing hydrogen both from renewable energy sources (solar-powered thermochemical cycles, biomass gasification, biological processes), and from fossil fuels (methane, GPL, for small applications and with solar-powered systems);
  • Studies of materials and processes for hydrogen storage.

Fuel Cells

  • Development of materials and components for different cell types (polymer electrolyte, molten carbonate, solid oxide cells);
  • Development and testing of small-sized generation/cogeneration systems, feeded both with natural gas, and with fuels derived from biomass gasification and anaerobic digestion.

Electric Storage

  • Development of new materials and components for electrochemical storage, such as lithium batteries and supercondensers;
  • Characterization and testing of storage systems for mobile and stationary applications.

All of these activities are performed thanks to the ENEA staff including about 50 researchers and technicians, specific experimental infrastructures (facilities and laboratories) located at the Casaccia and Trisaia Research Centres, and a network of collaborations with national and EU industries and research institutions.

Finally, in more mature fields such as wind energy, ENEA gives its innovative contribution on issues like materials, and participates in national and international collaboration activities allowing the Agency to play the role of technological observatory on technology and market development.


Reference Unit

Technical Unit for Renewable Energy Sources (UTRINN)
Head: Francesco Di Mario

Technical Unit for Portici Technologies (UTTP)
Head: Ezio Terzini

Technical Unit for Trisaia Technologies (UTTT)
Head: Giacobbe Braccio