This paper describes the results from a case study in the Danish medium-size industry. A heat-recovery system, producing 120 m3 of hot water per working day, has been constructed and has been in operation since the beginning of the year 2000.In this study, simplified procedures and networks for heat recovery were combined with economic evaluations based on suppliers’ offers and the marginal values of the investments. By logical procedures described in an earlier paper, the problem was reduced to the design and optimisation of a network for production of hot water. A short description of the basic ideas is given in the Appendix. This paper was presented at the ECOS'00 Conference in Enschede, July 5-7, 2000