Steam is a heat carrier for industrial plants that is relatively cheap to produce and distribute, compared to other heat transfer media aimed for the same temperature range. It is the most used medium in thermal power plants, but can also be used in a utility network in, for example, a refinery, where it is used to handle the heat distribution. Utility steam can be used to heat process streams up to about 250°C, while also having the ability to generate work. Management and optimization of steam networks can lead to heat, electricity and economic savings. However, many times, there are difficulties associated with data collection and measurements. This type of lack in information brings difficulties in the plant modelling and analysis. The present document, which has been carried out at the department of Energy and Environment at Chalmers University of Technology, aims to provide an explanation about how such an analysis should be done. By using engineering and thermodynamic knowledge, a model of the steam network is developed, first in spreadsheet databases, and then aided by a proper modelling software.