A Novel Knapsack Algorithm-Based Energy Routing in a Microgrid

The increase in penetration of renewable energy sources has transformed the existing grid into a multisource and multipath energy network. For real-time energy transactions in the new microgrid, it is essential to realize an energy router interface, which is the core of the energy internet. The energy router controls the bidirectional energy and data flow and achieves end-to-end energy transmission efficiently. With this consideration, this article proposes a new energy routing algorithm based on the knapsack optimization technique. The proposed work aims to minimize the net energy from the main grid and efficiently utilize solar photovoltaic (SPV) energy through meticulous energy routing. The effectiveness of the proposed work is validated for case studies with various types of loads viz residential, non-residential, and electric vehicle loads. In this work, the best set of loads for optimal energy routing with minimum energy costs are determined. The results show a substantial reduction ranging from 16 to 28% in the peak energy drawn from the grid and at the same time, the cost of electricity to be paid to the utility is noticeably reduced in the range of 39% to 50% for various load types. Further, a sensitivity analysis is carried out to evaluate the effect of variations in input parameters such as PV output, and load demand on the cost of electricity.