Open Access

Friedrich Rosenkranz

• In this project we develop an intelligent water meter based on software solutions offered by the IOTA Foundation. The water meter allows the customer to map water usage in real-time and pay water on demand, as well as the water provider to map water usage on a greater scale, regulate water supply during low- demand phases and offers regulatory functions to prepare for drought or humid climate, and to incentivise sustainable water usage in high-demand fields like agriculture. This functionality is phrased into a research issue: Invention of a working prototype to demonstrate the IOTA Streams and Wallet protocols for a meter with additional focus on economic efficiency and the technical preparation of scalability. Utilizing the IOTA streams protocol, a next generation secure data connection is established between the water meter and a server-sided software application. On this connection, water consumption is mapped into a data bench, and informative data and commands are issued to the graphical interface of the meter. The IOTA wallet library is leveraged to provide customer accounts corresponding to their meter. IOTA tokens can be send to the account, which grants access to water in a matter of seconds. Depending on the regulatory scenario, water flow can be stopped as soon as the account is exhausted (i.e. public well), or an overdraw can be established in order to guarantee fulfilment of basic human rights (i.e. private households). Since pricing data can be calculated server-sided and water consumption is mapped in very narrow intervals of as low as 4 seconds, the price can be used as tool to regulate consumption. The physical components include an electrical ball valve to shut down water flow automatically, a command line interface to provide informative data,, a Raspberry Pi running the client-sided software application, and a water meter with MBus-Interface, as well as a Controlling Board to connect the Raspberry Pi with both peripheral devices. The finished prototype shows, that water consumption can be mapped on a highly secure level, in near real-time, from afar, flexible for most applications.