Joint Electricity and Heat Optimal Power Flow of Energy Hubs

Abstract

Energy hubs as the intermediate in multi-carrier energy systems would enable various carriers, to be stored and converted. This concept requires an infrastructure to investigate the new upcoming economical as well as technical impacts on the system performance. The development in utilization of distributed generations, especially co-generation systems, along with movement towards more efficient systems creates sufficient incentives to promote energy service networks by coordinating numerous energy networks. District electric and heating systems provide electrical and heat energies, the most common demands for end-users. On the other hand, the heating load profile of the multi-carrier energy network can be modified to handle the heat and power interdependency in combined heat and power units. In this regard, this chapter endeavors to arise a general modeling and optimization scheme for coupled power flow investigation on various energy networks. The presented optimal power flow model includes conversion and transmission of multiple energy carriers. The connections between the power and heat foundations are precisely considered based on the recent impression of energy hubs. A generic optimality situation for optimal scheduling of multiple energy carriers is acquired. Moreover, the multi-carrier energy network takes advantages of the curtailable and responsive heating demand of DHN by employing a demand response program. In the suggested energy hub framework, the energy and continuity laws as well as the characteristic of district heating system’s major elements comprising heat sources, heat-exchangers, and the network of pipelines are modeled. The district heat network analysis would specify the supply and return temperatures at each node and the mass flow rates in each pipe. In addition, electric network operation constraints such as voltage magnitude of buses and line flow limits have been taken into account. Finally, the simulation outcomes are deliberated for a test system to establish the applicability and effectiveness of suggested model in the multi-carrier energy systems.