1. SESAM The Sustainable Energy Systems Analysis Model is a generic multi-scenario model. A SESAM model may represent a local, a national or a regional energy system, comprising several countries. A SESAM model is a physical model. A SESAM database comprises 25 data registers in which the present and the possible future structural and physical properties of the energy system in question as well as data specifying alternative quantitative development factors are registered. Moreover, for economic cost assessments, the specific investment and maintenance costs assigned to each particular type of system component are registered in the database. The SESAM programs compute the energy flows in the system on a monthly and diurnal basis. SESAM is not a forecasting model. It serves to provide comparative analyses of alternative long-term development strategies, specified in terms of alternative investment programs.

2. Energy sources Conversion and transmission End-use The general SESAM energy systems concept The different means of transport constitute an integrated sub-system

3. The design and functioning of energy-efficient systems, in particular the integration of vehicles. Electric power from the grid can be converted to motive mechanical power in vehicles in different ways: - Directly from overhead wires to electric motors. - Indirectly by means of batteries. - Indirectly by the conversion to a chemical potential (e.g. as hydrogen) and the subsequent conversion to electrical/mechanical power in fuel cells or combustion engines.