The company ROM AG in Frauenfeld would like to analyse the energy and substance flows in the summer-, winter- and yearly- periods. These analyses are necessary to improve the technical process and to increase the economic efficiency.

In the first part of this dissertation it was useful to divide the work into different scopes of duties. In the beginning the process of fermentation had to be studied. An important knowledge is that the energy capacity of the biomass must be calculated through the carbon content. After that the operation data of the cogeneration was evaluated. One demanding exercise was the energy analysis of the rot-hall. The result of the electric-analysis showed that the energy consumption of the ventilation system is very high, especially from the rot-hall.

With the monthly produced heating energy and the thermal consumer it was possible to calculate surplus heat. Finding a possible use for the thermal surplus was a target of this study. This heat exists only in the transitional and summer period. The maximum is in the late summer time.

Possible use of the thermal surplus energy are:

• heat supply to companies with a high hot water consumption
• seasonal storage for heating of housing estate and office buildings
• in the process of fermentation because the company has the intention to increase the mud proportion.