Efficient Hydrogen Liquefaction Processes

Global and local emissions of polluting gases give a strong demand for more environmentally benign strategies for the future. Hydrogen as an energy-carrier has been pointed out as an important key in this picture in the medium- to long-term perspective. Technologically the issue of transportation and storage of hydrogen are key issues in realizing an infrastructure for this energy-carrier. Transport and storage as liquid in parts of the chain is very likely, due to the high energy density in this state. The efficiency of production of liquid hydrogen today is relatively low, maybe 30%. This is of course possible to improve. However, how can it be done practically and, very importantly, to an acceptable cost? This is a key issue for research in many coun tries. SINTEF and NTNU have a very good basis for contributing in this development through the extensive and successful development done within liquefaction of natural gas. This basis is available and the work to transfer and refine it for liquefaction o f hydrogen has started. This is, however, a complex area with need for long-term strategic development. This project will make a contribution in improving the energy efficiency for liquefaction, and also for only partial cool down, if this turns out to b e a requirement in parts of the chain. Such a partial cool down may be equivalent to the pre-cooling part of liquefaction. The energy sector is an area where Norway has vital interests and very good possibilities and basis. With the prospect of the lique faction of hydrogen being an important technology in the future energy industry of Norway, it is very important to have independent knowledge within this area. The Norwegian Hydrogen Committee points out that the Norwegian competence community should be in the forefront internationally within storage technologies, and liquefaction is mentioned as one of the important areas for basic strategic research (NOU 2004:11, page 82)