Beyond the electricity-only production: towards a multi-generation world

The emerging technologies for small-scale distributed generation are shifting the focus from the centralized to the local production of electricity. Besides the electricity-only production, the evolution of small-scale cogeneration units is enabling energy efficiency improvements with respect to the separate production of electricity and heat. Additional benefits may be obtained by exploiting the potential small-scale cooling production technologies. The combination of technologies to form distributed multi-generation systems is one of the most promising issues in the evolution of the energy sector. This paper discusses the technologies and schemes allowing for effective deployment of distributed multi-generation solutions, and introduces the relevant efficiency indicators and the technical aspects concerning the interaction among the equipment producing different types of energy. Specific trigeneration solutions (for combined production of electricity, heat and cooling) are analyzed in detail. Finally, the potential energy and economic benefits from adopting distributed multi-generation systems are outlined.