Many significant features lead to consider hydrogen as an interesting energy carrier. Hydrogen can be burned with pure oxygen thus the production of CO2 and NOx is avoided. Since molecular hydrogen does not exist on the earth it has to be produced from fossil fuels or from renewable energy sources. Energy from fossil fuels can be transferred into hydrogen and released elsewhere. So relevant reduction of emission of pollutant can be achieved in critical zones at the centres of large cities. Nevertheless the losses occurring during production, distribution and storage of hydrogen lead to an increased consumption of the primary energy source (fossil fuels) and to increased emission levels (CO2 and others). Hydrogen can be obtained from renewable sources such as the solar energy and used in situ for power generation. In this case hydrogen can act as an energy carrier which allows a local energy storage. In such a way the time dependent availability of the solar energy and the production level of the power plant can be decoupled. In a distributed generation context a small size solar power plant equipped with a hydrogen storage system has been studied. Different storage options have been investigated and compared. Finally a liquid hydrogen storage system is proposed. The peculiarities of the selected system allow a reduction of losses, size of machinery and energy requirements. The paper presents an analysis of the more relevant issues related to the different hydrogen storage options suitable for the present application. After the characterization of the solar field in terms of energy availability and the specifications of both the hydrogen production system and the power generation unit, the design of a liquid hydrogen storage system is presented and widely discussed. This method is particularly useful in the plants management (for example nuclear or coal plants), where it’s impossible or very difficult to modify power level, as well. So, such a static system would be useful in order to allow power modulation by H2 plant. In order to do this, a research for individuating high volumic (and mass) specific capacity systems should be driven.
Highly Efficient Liquid Hydrogen Storage System by Magnetic Levitation Using HTS Coils
