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In the planned process biogas will be cleaned and subsequently transformed into liquid biomethane (LBM) and solid carbon dioxide (dry ice). Thus biogas is transformed in an energy rich storable and easily transportable energy carrier. An important precondition for the process is an individually adapted gas cleaning system, which separates impurities (e.g., NH 3 , H 2 O, H 2 S etc.) from the biogas. Subsequently the pre-cleaned biogas (now consisting mainly of CO 2 and CH 4) is fed into the liquefaction unit. Core pieces of this system are two heat exchangers connected in series with operating temperatures of about 200 and 120 Kelvin. The first heat exchanger works as a precooler and might also be used as a backup for freezing out impurities. Triggered by the deep temperatures reached in the second heat-exchanger, the CO 2 flocculates. A purity of 99.9% CH 4 in the liquid phase could be guaranteed, as only CH 4 has its dew-point at the operating temperature of 111 Kelvin. The low pressure and the absence of toxic chemicals are further benefits of the specific process. A high-quality cryogenic and liquid energy source arises by cutting off CO 2 and by the liquefaction of CH 4. This energy source has an upper heating value of 5.87 kWh/l at a temperature of 111 K (biogas: 0.0055 kWh/l at 300 K). By increasing the volumetric energy by the factor of 1000 (compared to biogas), transportation to highly efficient energy plants becomes reasonable. Goals of the project are to proof the feasibility of a decentralized long-term storage of large energy amounts, to show alternative ways in using transformed biogas and an efficient usage of the energy content of the raw gas. Additional marketing possibilities of dry ice and LBM could ensure an economical operation outside the German EEG (Renewable energies act).

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Modern hospitals are not only places of treatment, healing and scientific research, but bureaucratic colossi whose administrative and organizational structures changed fundamentally through the gradual implementation of new innovative office technologies in the first half of the 20th century. Against this background of media technological change the article aims to trace the fundamental transformation of administrative practices in hospitals between 1890 and 1932, using the Charité Berlin as an example, and paying attention to the ways of transmission and adaption of these new office technologies such as typewriters, photocopiers, file folders, card index and punch card systems into clinical administration.