Distributed polygeneration in load sharing approach
Creators: name: Canelli, Michele
Publisher: name: Università degli Studi di Napoli Federico II
Year: 2015

description: The thesis work deal with polygeneration, the combined production of more than one energy vectors from a single primary energy source, in residential and tertiary sectors. In particular the thesis focuses on micro or small polygeneration systems that are placed immediately at the consumer's site. This concept, often referred as distributed polygeneration, differs from the dominant architecture of the current electricity system based on large scale centralized power generation. Compared to the separate production, polygeneration leads to primary energy saving and greenhouse gas benefits. However, in order to ensure a high market penetration of these promising technologies in residential and tertiary sector, it is essential to deal with some issues, such as the high investment payback period and the potential negative effects on the electricity network related to a large diffusion of distributed generation. In order to overcome this issues different possible solution were investigated by means dynamic simulations. One interesting solution could be the load sharing approach, which consists in the introduction of a small electric and thermal micro-grid allowing the sharing of electric, thermal and cooling loads among a group of diversified end users. By sharing the load among different types of final users (residential, commercial, institutional, etc.) it is possible to increase the operating hours of the MCHP system. Moreover the introduction of an energy service company that manages a large number of systems distributed on the territory, often referred as virtual power plant, could obtain some advantages related to the managing of a high number of polygenerator system. Others possible solutions analyzed in this thesis are related to the increasing share of self-consumed electricity "produced" by the MCHP system. In this way it is possible to reduce the potential impact related to the large diffusion of distributed polygeneration systems and improve the economic performance of the MCHP. In order to increase the share of self-consumed electricity two different strategies are analyzed. The first consists in the careful selection of the user in which the MCHP system is installed, while the second relies on the interaction between the MCHP system and the electric vehicles charging. Another interesting solution analyzed in this thesis refers to the introduction of hybrid energy system that combine two or more energy conversion devices, that when integrated, overcome limitations inherent in either. Finally the use of Urban Energy Maps to locate an urban area suitable for the introduction of a polygeneration system is investigated. The methodology was applied to the historical centre of Benevento in order to design a polygeneration system and a district heating and cooling network able to meet the energy requirements of a cluster of users. The findings of this thesis confirmed the energy and environmental advantages related to the diffusion of distributed polygeneration systems. In addition to these advantages, already shown in scientific literature, this work identified different solutions in order to overcome the main disadvantages of this promising technology. In particular, the load sharing approach, the introduction of virtual power plant managed by an energy service companies, the integration of electric vehicle charging with an MCHP, the careful selection of the end users in which the MCHP system is installed, the introduction of hybrid MCHP system, the use of urban energy maps in energy planning problems, are promising solutions that can concur to the overcame the main issues that hinder the diffusion of distributed polygeneration system.