Monitoring and automation of the critical infrastructures like the power grid are improvised by the support of an efficient and secure communication network. Due to the low-cost, low-power profile, dynamic nature, improved accuracy and scalability, wireless sensor networks (WSN) became an attractive choice for the Information and Communication Technology (ICT) system of the smart grid. However, the energy efficiency and security of WSN depend highly on the network design and routing scheme. In this paper, a WSN-based secure and energy-efficient remote monitoring technique (SERMT) is proposed by demonstrating a WSN-based ICT network model for pervasive monitoring of the generation and transmission part of the power network in a smart grid system. The performance of the proposed network model designed for a smart grid of IEEE 118-Bus system coupled with the secure routing technique is tested during cyber-attacks by means of NS2, and the simulation results indicate that it performs better than existing smart grid monitoring methods like Lo-ADI (Dhunna and Al-Anbagi in IEEE Sens J 19(13), 2019 ) with respect to packet drop count and throughput.