Recently, wireless sensor networks (WSNs) have attracted a lot of interest due to their applications in numerous fields, such as home security, environmental monitoring, critical infrastructure protection and energy power. Moreover, WSNs are combined with blockchain to provide trust, transparency and traceability for electrical power systems, military applications, and commercial applications. This article will present the main units of a sensor node used and the implementation of a sensor node used for multi-purpose applications in the energy field. Also, we will present the hardware implementation of a low-power and low- cost sensor node designed for measuring environmental parameters and storing on blockchain.