Combined Heat and Power Systems (CHP) have a potential to be used widely in many areas of industry as a powerful tool for energy conservation. But their application should be carried out in the most efficient way to gain the most from this energy potential. In this paper, the batch/semicontinuos process is revisited as a complex but promising area for energy savings when using appropriate CHP methodologies which would contemplate an integrated view of the process energy requirements and its utility system structure. The new methodologies, supported by appropriate software, comprehend adequate design tools for the simulation, fine tuning and design optimization of the CHP System, thus constituting a new major breakthrough in energy conservation for total sites. Results obtained from both benchmark case studies and industrially based examples are presented which indicate that a successful and general design methodology has been developed for process integration with Combined Heat and Power systems in time-dependent processes, allowing for important cost reductions leading up to 30% in the plant design profitability.