Case study concerning the opportunity of installing cogeneration system in an existing industrial site

The combined production of heat and power using cogeneration systems is one of the investigated
area to reduce the global CO2 production of the industrial activities in Europe. Due to the time
scale of the investment, the appropriate sizing of a cogeneration unit is critical for defining the
financial feasibility of the project. The possible efforts that could be made during this time scale
for improving the enorgy efficiency of the process can make the cogeneration system oversized or
even useless. In this paper, we present two methods that we applied to compute the appropriate
size of a cogeneration system to be integrated to an industrial site. The first is directly based ôn the present steam consumption figures. This approach is easier and simpler but the solution is not
sure for the future, it leads to a 5.6 MW gas turbine but without reducing the overall energy
requirements of the plant. The second is based on energy integration including the optimal use of
the steam network for CHP. This approach has the advantage to provide a reliable solution for the
future. Using this approach, we have computed an energy savings potential of 60Vo, the energy
requirements being satisfied by a 4.6 MW gas turbine, and the possibility of producing a
complementary 3 MW with steam turbines.