RainMachine Can’t Make It Rain, But Helps Homeowners Keep Gardens Growing

By Mary Catherine O'Connor

By linking home irrigation systems to weather forecasts, the new solution saves water and money.


Andrei Bulucea says he can’t make his rain machines fast enough. The drought in the Western United States is making consumers far more conscious of the amounts of water they use on their lawns. As a result, RainMachine, for which Bulucea serves as the chief technology officer, is having a banner year.

Engineers from Sun Microsystems and Nortel Networks founded the company in 2011 to develop a product that could leverage the Internet of Things, in order to help homeowners more easily conserve energy and natural resources. “We chose to work with water,” Bulucea explains, “mainly because we noticed that so much city water was being wasted by legacy home irrigation controllers, including the ones that were running our homes.”

The RainMachine system accesses the NOAA-managed National Digital Forecast Database every six hours to download the latest weather data based on a user’s GPS coordinates.

RainMachine began rolling out products in 2013, and now offers two models that can manage how much water is used to irrigate between eight and 12 individual zones around a user’s property. A third model, which can control 16 zones, is slated to be made available on July 10. The RainMachine replaces a homeowner’s existing irrigation valve controller.

The Wi-Fi-enabled RainMachine system uses the National Digital Forecast Database (NDFD) managed by the National Oceanic and Atmospheric Administration (NOAA), which the RainMachine monitor accesses, via a homeowner’s Wi-Fi router, every six hours in order to download the latest weather data based on the user’s GPS coordinates. It then updates every zone’s watering schedule, based on both the water needs of the plants within each zone and the seven-day forecast regarding temperature, wind, moisture and rainfall levels.

The RainMachine device, which runs a full Linux operating system, performs calculations locally (as opposed to within a remote cloud server) to determine an appropriate watering schedule. More specifically, RainMachine uses the NDFD data to determine the evapotranspiration rate, or the movement of water into the atmosphere from soil and vegetation, at the user’s home.

Homeowners can employ the RainMachine application, available for either the iOS or Android operating system, to view the schedule or make any changes. This can include reconfiguring the watering zones or updating the schedule to comply with a municipality’s drought-related watering requirements, such as only watering on certain days of the week.

The sprinkler heads, sold separately, are hardwired to the RainMachine controllers—which is required since the irrigation valves are actuated via a 24-volt alternating current power line. RainMachine is compatible with all popular home irrigation valves, Bulucea says, because 24VAC valve controllers are standard. The RainMachine devices have touch-screens that mirror all of the same controls as the smartphone app. According to Bulucea, a browser-based interface to the RainMachine controls—which would allow users to log on from any Internet-connected computer—is one of the chief requests that current RainMachine users are making. The company has developed such an interface, he says, and is currently alpha-testing it.

RainMachine is one of a number of Wi-Fi-connected sprinkling system controllers being marketed for residential use. Others include Rachio, which works in a roughly similar manner as RainMachine, except that users can elect to collect forecast data from their own or other local weather stations, and GreenIQ, which sets watering schedules based on local weather station forecasts, and can be used with Wi-Fi-based soil-moisture sensors sold by Parrot or Koubachi.

Eventually, Bulucea says, homeowners will be able to link their RainMachine controllers to smart water meters (which communicate wirelessly to a utility provider) in places where utilities supply such devices. Such integration would allow users to do such things as set alerts to trigger if their monthly water bill approaches an established threshold, so that they can take further steps to conserve water beyond what their schedule allows. Integration could also alert users to a leak in their irrigation system, based on water usage. But according to Bulucea, many cities that do use smart water meters have proprietary systems that can be difficult to tap into.

Weather forecasting is emerging as a significant player in IoT systems, with commercial irrigation-management providers such as HydroPoint leveraging weather forecasting data from a range of sources, and then managing controllers via an Internet-based interface. Earlier this year, IBM and The Weather Channel‘s business-to-business arm, Weather Services International (WSI), announced a partnership through which IBM and WSI are developing tools for anticipating major weather events, and then leveraging the Internet of Things and data analytics to mitigate the estimated $500 billion in weather-related losses that businesses suffer annually.