Improving the consumption and water heating efficiency in smart buildings

In apartments, houses and hotels, showers are by far the biggest consumers of water, responding to about 25% of the total volume consumed every month. When winter hits big cities and temperatures fall, the hot water consumption increases dramatically. Since end users often dispense cold water present in the pipelines until the heated water from the reservoirs is perceived in showers or other points of use, hotels and residential buildings are responsible for a considerable waste of treated water. Several solutions based on local hardware have been proposed to partially overcome this problem, but many of them try to reduce the waste of water at the expense of reducing the efficiency of the heating and recirculating systems. The age of the IoT has brought to the smart buildings new perspectives regarding to rational use of resources, providing savings and real comfort for users. This work proposes a smart water heating scheme, mediated by IoT technology, for large buildings in urban settings. The main goal is ensuring the minimal waste of water as well as energy economy in pumping and heating systems. The proposed automated solution is built from an open-source Asterisk-based IP-PBX on cloud computing technology. A complete experimental setup considering a residential building in the southeastern region of Brazil is implemented and tested. The achieved benefits are tangible and significant when compared to the dedicated existing systems.