The HYDROSOL Projects



HYDROSOL Project Summary


Problems to be solved:

High intensity solar radiation can be obtained by existing parabolic reflectors that track the sun via heliostats. The areas of southern Europe which posess high insolation and potential for installation of the associated solar tower plants are largely coincident with economically depressed regions. The conversion of the so obtained solar energy into transformable forms such as e.g. reduced chemical compounds able to be re-used as fuels (“solar fuels”) is a concept of major importance. One of the reactions that has tremendous economical interest because of the low economical value of its reactants as well as because of the high economical value of its products is the dissociation of water to oxygen and hydrogen. The HYDROSOL Project is an effort to employ a renewable energy source, the sun, to directly produce hydrogen, a “clean” fuel considered to be the energy carrier of the future given the advancement of fuel cell technology and hydrogen storage/handling systems.

Scientific objectives and approach:

By far the most economically attractive reaction for the production of hydrogen is the decomposition of water and the direct production of pure hydrogen. However because of unfavorable thermodynamics worthwhile yields can only be achieved at very high temperatures imposing therefore technological difficulties to any ideas trying to couple the sun as the source of driving energy for the reaction. Catalytic materials are therefore required in order to lower the reaction temperature. The hydrolysis reaction is carried out via a two step process. In the first step the activated catalyst dissociates water and produces hydrogen while in the second step the used catalyst is regenerated. The concept has been proven experimentally, however the catalyst regeneration temperatures are still high (i.e. >1600°C). The aim of this project is to exploit solar energy for the catalytic dissociation of water and the production of hydrogen. The basic idea is to combine a support structure capable of achieving high temperatures when heated by concentrated solar radiation, with a catalyst system suitable for the performance of water dissociation and at the same time capable of regeneration at these temperatures, so that complete operation of the whole process (water splitting and catalyst regeneration) can be achieved by a single solar energy converter. The purpose of this project is thus two-fold: 1) development of novel catalytic materials for the water dissociation reaction at moderate temperatures (800-1100 C) and of the associated coating technology on supports, and 2) integration of the developed material technologies into a solar catalytic reactor suitable for incorporation into solar energy concentration systems, opening the road towards a complete hydrogen fuel production unit based solely on solar energy.

Expected impacts:

The integration of systems for concentrating solar radiation with reaction systems able to split water molecules forms a system of immense value and impact on energy supply and economics worldwide. The project concerns a key technology for using solar heat to drive chemical processes (hydrogen production) aiming at reaction yields which, when obtained at the temperature interval described above, are a significant improvement of the current, techncally impractical, state of the art and open serious possibilities towards commercialization of the technology. The project will have a significant impact both in contributing to the achievement of ecological objectives (emission reduction, natural source preservation) as well as in job creation and economical growth, especially to not yet fully developed EU areas since these largely coincide with regions/latitudes of high levels of direct solar flux.


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