A review on the integration and optimization of distributed energy systems

The depletion of fossil fuels and climate change pose huge challenges to sustainable development. How to meet the increasing energy demands in an efficient and environmentally friendly manner has become the focus of attention all around the world. The hybrid combined cooling, heating and power (CCHP) systems that combine fuel powered CCHP systems with high energy efficiency and renewable energy technologies with zero emissions are attractive. Hence, this paper reviews various studies on such systems. Firstly, the possible integration forms of available technologies are summarized, which include combined heating and power systems, waste heat recovery systems, solar energy systems, geothermal energy systems, wind energy systems as well as energy storage systems. Secondly, the different application scenarios such as neighborhood level, district level and city level are summed up. The primary concern at the neighborhood level is whether the allocation of benefits needs to be considered. The core of the district level is how to properly decompose the district into multiple sub-districts. Research on the city level is to provide valuable guidance for the harmonious development of the city. Finally, on the basis of the above review, several perspectives that require further efforts are put forward. • The possible integration methods of available energy technologies are investigated. • The application scenarios of distributed energy systems are detailed in three levels. • Several potential perspectives are proposed based on the current studies.