Solar energy storage challenge

Nevertheless long-term heat storage is one of the main challenges for an effective year round use of thermal solar energy. Therefore, high energy density heat stores are the focus of an increasing amount of research efforts. 

Storage of Solar Energy The New Challenge, and The Hydrogen Solution... 

More down-to-earth challenges do get attention from thermodynamics scientists such as supercritical polymerizations, energy storage via organic solar cells, copolymeric compatibilizers in the interphase of compressed heterogeneous polymer blends, membranes and monolayers. 

The splitting of water into O2 and H2 is a major objective for the storage of solar energy into chemical fuels [107]. Two half-reactions are involved, namely, water oxidation, releasing O2, H, and e , and reduction of protons to H2. Water oxidation is a challenging process because of its multi-electron and multi-proton nature. 

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