One of the main problems in home networked systems is the wide diversity of technologies, application requirements and cost allowance for devices and systems in general. This is translated to a division into different islands of technology that goes down to single manufacturer systems, thus blocking the way to the system integration as the main reason for the existence of the network. It is widely accepted that achieving the interworking is the most important aspect of a system specification. Object-oriented modelling associated with proper application management mechanisms for trading and binding provides the best approach to standardisation work on home systems interworking. We take here as an example the work toward an interoperability specification for an energy management system. The system described spans several communication media and brings together several consumer and producer entities. The system aims to provide increased comfort while either minimising the usage of resources or their cost for the same level of usage. Results from installed and running systems show the success of the approach.