In the last 10 years, large investments are present in the development of technologies for obtaining energy from RES that requires an understanding of the systems for RES. Solar energy, i.e. technology that uses solar energy, although with a relatively low efficiency, has a huge space for development. Thus, the implementation of solar technology (direct conversion of solar energy into electricity) covers the market of wide scale. Since photovoltaic (PV) cells can only produce energy only during solar irradiance, the generated energy needs to be stored and used at night when it is not possible to produce energy from solar energy. Existing storage technology is insufficiently developed and very often expensive, which is an important limitation. In this context, hydrogen technology is developed with an emphasis on hydrogen production using OIE.