High efficency integration of thermodynamic solar plant with natural gas combined cycle

ENEL and ENEA have joined forces on the Archimede project, the world's first integration of a thermodynamic solar energy system into gas-fired combined-cycle power plant. The integration between the two systems allows to focus investments on the innovative components of the solar part making use for the energy conversion of the already existing power generating system. The solar thermal energy system combines the technologies of parabolic trough collectors and power tower systems, adopting a range of important innovations to solve the problems associated with both approaches. The mirrors have retained their parabolic trough form with technological advances that permit the use of a new molten-salt fluid, making it possible to achieve the high temperatures typical of tower systems. The site of application will be the ENEL power station of Priolo (Siracusa), where a solar field will be built in a 40 hectars area close to the power station which consists of two gas fired combined cycles of 380 MWe each. Solar energy is collected by parabolic optic concentrators which transfer it to a fluid made by molten salts of sodium and potassium nitrates. In particular, a preliminary project has been developed for the integration of a solar plant with the latest generation of ENEL combined cycle plant consisting of two 380 MWe groups. The solar part will contribute with peak electric power of around 5 MWe, added to the nominal preexisting power of the plant, and will use the existing system and services for the thermodynamic cycle (plant, staff, infrastructure, etc.), the technical characteristics of which were found to be compatible with the project specifications.