# Toward Secure Smart Grid Systems: Risks, Threats, Challenges, and Future Directions
## 3 Limitations and Challenges
### Smart Grid Challenges  
Smart grid challenges are based on security and safety obstacles and complexities surrounding the deployment and development of the smart grid infrastructure, as well as the development and deployment of its systems. These challenges are often the result of integrating advanced technologies, maintaining infrastructure, and implementing upgrades. Table 9 presents a set of existing challenges that can be divided into three categories: security-based challenges, safety-based challenges, and additional challenges, with their respective challenges listed under each category. The first two categories are described below. * Security-based challenges: These cover risks and vulnerabilities associated with securing the smart grid infrastructure by using cyber-physical security means to protect and preserve data privacy [74] and prevent unauthorized access [75]. Other security measures include ongoing network, system, and device behavior monitoring, risk assessment using cryptography and non-cryptography solutions, and robust security controls [69; 76]. * Safety-based challenges: These depend on demanding tasks to guarantee the secure management, upkeep, and operation of the smart grid system, which prove to be very challenging, especially with the deployment of advanced grid technologies and systems [77]. Other safety challenges include the following. The integration of DER introduces bidirectional power flows, which can challenge conventional protection systems that were designed for unidirectional current [78]. This may lead to unintended power circulation, difficulties in fault detection, and potential islandingduring outages. To mitigate this, adaptive protection mechanisms, directional relays, and standards like IEEE 1547 [79] are essential to ensure safe DER-grid interaction. The likelihood of configuration mistakes, operator overload, and cascading failures during anomalous events also increases with the increased system complexity [80]. This requires sophisticated automation technologies, streamlined system designs, and intensive training for operational staff. Failures in communication networks are the result of communication between control centers, substations, and field devices being uninterrupted in real time for smart grid activities to function [81]. Whether intentional or unintentional, a breakdown in these communication channels could compromise grid stability, lead to inaccurate actuation, or delay decisions. Mitigation strategies include network redundancy, real-time monitoring, and fallback methods that allow autonomous local control during interruptions. Security breaches often occur when attackers modify control orders, sensor data, or protection logic in smart grids, leading to cybersecurity vulnerabilities that directly translate into safety hazards [17]. Such violations could result in equipment damage or power outages by disabling fail-safes or establishing hazardous operating conditions. Protecting safety functions requires enhancing security through the use of intrusion detection systems, encryption, authentication, and security-by-design procedures. Interoperability issues with protection systems occur when devices from various suppliers are frequently integrated into smart grid environments, even though they may not have the same operational logic or communication protocols [82]. Due to a lack of interoperability, protection responses may be delayed or fail to activate during hazardous situations. To guarantee dependable, coordinated protection across systems, standardized communication protocols such as IEC 61850 must be adopted, and extensive integration testing must be performed. Addressing these challenges requires close collaboration and coordination among smart grid stakeholders to guarantee the safety, security, and reliability of the electrical system [83].