The article describes the design of an Internet of Things based platform having as main objective the real-time management of energy consumption in water resource recovery facilities and their integration in a future demand side management environment. The monitoring of several electrical parameters, including energy consumption, is done via a dedicated energy meter, whose design is detailed in the article. The high level data communication from the energy meters to a central platform of the wastewater utility is done via the MQTT protocol. Within the water resource recovery facility, the access network is based either on Wi-Fi or LoRa, which are two enabling technologies for the Internet of Things. The meters are deployed in pilot demonstrators located in two water resource recovery facilities in Lisbon, Portugal.