Smart Irrigation Controllers in Residential Applications and the Potential of Integrated Water Distribution Systems
Nathan T. Lunstad, Robert B. Sowby
Abstract
Drought and population growth, especially in the western United States, are propelling a need for more efficient irrigation. Smart irrigation controllers, which interface with soil moisture, evapotranspiration (ET), or weather sensors, have been promoted as a demand-side management tool for this purpose. This paper reviews the body of research on residential smart irrigation controllers and their effectiveness. We find that smart irrigation controllers consistently reduce water demand by 15% among general users and more than 40% among indulgent users. Gaps in research include studies addressing peak demand reduction, centralized communication, data verifiability, and human factors of landscape management. Future work may develop techniques for coordinating networks of smart irrigation controllers to enable greater shifting and shaving of discretionary irrigation demands, similar to what is already happening in the electric grid, thereby creating an integrated water distribution system (IWDS). An IWDS may utilize smart irrigation controllers as direct load control devices at customer end points and interface with advanced metering infrastructure (AMI) and supervisory control and data acquisition (SCADA) systems at a central location to create more effective demand-side management (DSM) strategies for water conservation.