Tactical price-setter scheduling of a network-constrained integrated energy system under high penetration of solar distributed generations

Abstract

The growing penetration of solar distributed generations (SDG) in integrated natural gas, electricity and heating systems will be challenging as these networks are intricately entangled. This study investigates the tactical price-setter behavior of an embedded network-constrained integrated energy system (NIES) in the wholesale electricity market (WEM) via a bi-level optimization framework under high penetration of solar distributed generations (SDG). The proposed NIES consists of an 8-node district heating system (DHS), a 20-node natural gas network (NGN) and IEEE 33-bus active distributions system. The first optimization level models the NIES operator that deploys thermal and electrical flexibilities as well as line-pack capability of the NGN pipelines to minimize the energy provision cost. Furthermore, it also strategically submits offers/bids in WEM as a price-setter. At this stage, the second level optimization is the WEM operator that receives offers/bids and clears the WEM (modeled by IEEE 6-node transmission network), aiming to reach maximum communal satisfaction. The intermittent SDG production is dealt with via the robust optimization (RO) approach. The results emphasize that the flexible energy technologies (line-pack, electrical and thermal flexibilities) can enhance the capabilities of NIES in influencing market price, and that leads to an 8.77% lower overall operational costs.