energies Article Cyber Attacks in Transactive Energy Market-Based Microgrid Systems Rumpa Dasgupta * , Amin Sakzad and Carsten Rudolph   Citation: Dasgupta, R.; Sakzad, A.; Rudolph, C. Cyber Attacks in Transactive Energy Market-Based Microgrid Systems. Energies 2021, 14, 1137. https://doi.org/10.3390/ en14041137 Academic Editor: Edmund Widl Received: 13 January 2021 Accepted: 17 February 2021 Published: 21 February 2021 Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affil- iations. Copyright: © 2021 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/). Faculty of Information Technology, Monash University, Clayton, VIC 3800, Australia; amin.sakzad@monash.edu (A.S.); carsten.rudolph@monash.edu (C.R.) * Correspondence: rumpa.dasgupta@monash.edu Abstract: Due to the increasing integration of distributed energy generation in the electric grid, transactive energy markets (TEMs) have recently emerged to balance the demand and supply dynamically across the grid. TEM enables peer to peer (P2P) energy trading and brings flexibility by reducing users’ demand in the grid. It also enhances the system’s efficiency and reduces the pressure on electricity networks. However, it is vulnerable to major cyber attacks as users equipped with smart devices are participating autonomously in the energy market, and an extensive amount of information is exchanged through the communication channel. The potential attacks and impacts of those attacks need to be investigated to develop an attack resilient TEM-based power system. Hence, in this paper, our goal is to systematically identify possible cyber attacks associated with a TEM-based power system. In order to achieve this goal, we classify the attacks during the P2P and flexibility schemes of TEM into three main categories. Then, we explore the attacks under each category in detail. We further distinguish the adversary roles of each particular attack and see what benefits will be received by an adversary through each specific attack. Finally, we present the impact of the attacks on the market operation, consumers, and prosumers of the TEM in this paper. Keywords: microgrid system; transactive energy market; peer to peer energy trading; flexibility scheme; cyber attacks; impact analysis 1. Introduction The introduction of distributed energy resources (DERs) in traditional electricity systems as a means of energy production brings a number of advantages, such as reducing environmental pollution, lowering the electricity cost of DER owners, minimizing system cost, and so on [1]. Moreover, DER owners can convert from consumers to prosumers by selling their surplus energy generation to other consumers and the grid [2]. For efficient energy management and incentivizing the DER owners properly, a new market framework called the transactive energy market (TEM) has emerged [3]. TEM encourages small-scale generators and consumers to join in conventional electricity markets to produce, sell and buy energy. The conventional grid, where electricity is generated mostly in large central generators, brought to the distribution centers, and then distributed to the end-users, is upgrading to a smart grid through merging Information and Communication Technology (ICT) across the grid [4]. TEM enables Peer to Peer (P2P) energy trading in the grid [5], which makes a connection between consumers and prosumers for trading energy with each other. In the P2P energy trading, energy from small-scale DERs in dwellings, offices, factories, etc. is traded among neighboring prosumers and consumers. The benefits of P2P energy trading are bifold as the prosumers get financial advantages by selling their excess renewable generation, and consumers buy electricity at a cheaper rate from their peers instead of the grid. Moreover, implementing TEM in the smart grid enables flexibility schemes where prosumers/consumers can modify generation or consumption patterns of DERs based on Energies 2021, 14, 1137. https://doi.org/10.3390/en14041137 https://www.mdpi.com/journal/energies