Droughts are climatic events of gigantic proportions and unfortunately, California is currently experiencing one of the most severe droughts in recorded history. Predicting the length of a drought is difficult and often times predictions end in disappointment.
An irrigation controller, in essence, is a local drought fighter device. It helps irrigate your lawn, keeping it green and healthy, even during dry spells. Unlike the RainMachine, a traditional irrigation controller is unaware of the climate surrounding it, dispensing the same amount of water day after day, year after year. By using the RainMachine your home just become smarter: during cold periods (droughts have cold periods too), the RainMachine lowers the amount of used water according to temperature. The savings become more apparent during spring, autumn and wintertime.
Often times during a drought, local communities force users to conserve water by imposing watering schedules. The RainMachine is perfect for complex watering schedules such as “water every number of days", or water restrictions on predetermined days. Despite complicated watering schedules, the RainMachine is able to calculate the required amount of water required by evapotranspiration for up to 7 days.
Because of the persistent drought in California, we saw a strong demand in smart irrigation devices. Unfortunately, we cannot fix the drought, but we can help you adapt. Join the water conservation movement! Because we believe in our idea, our open source software is available on all devices. Use it, share it and improve it. The water belongs to us.
Over the past year, using thousands of RainMachines in California we calculated that the total amount of water saved can measure in Olympic size swimming pools and MegaW/h of energy required to pump the water. This is Enough power required to fully charge 10 million mobile phones or the equivalent of driving half million miles!
RainSensitivity is a feature that was introduced in Nov 2014 with RainMachine smart Wi-Fi irrigation controller, build 3.63.
This software update is available to all our RainMachine users.
As the user manual states, Rain Sensitivity allows for an arbitrary attenuation of the forecasted rainfall amount. As a result, particularities such as non-uniformity, runoff or overall rain forecasting amount can be adjusted up or down. Default is set to 80% of the rainfall amount. This is a conservative approach that will cover most situations. Decreasing rain sensitivity will increase the amount of irrigation water used because a lower amount of rainwater would be considered in the algorithm. In an ideal world, rain sensitivity should be 100%.
RainSensitivity was designed as an adjustment/correction for your local climate or microclimates. The NOAA forecast compute engines do account for climate influence over weather but this method isn’t 100% accurate. In gardening speak, a tree or other types of rain obstacles can be considered as microclimate elements and of course the NOAA does not see these.
If you think that your reported rain data is consistently off the mark (you can check reported amounts against a local sensor, for example) the Sensitivity allows you to adjust the Quantitative Precipitation Forecast (QPF) values with values from 0 to 100%. Default is 100%.
Never adjust this setting based on only one weather adjustment! In other words, you need to adjust for climate and not for the weather. If you are unsure of this setting, leave it alone! :)
Another feature introduced on Nov 2014, at the same time as RainSensitivity, is the FieldCapacity variable.
Field Capacity is a measure of the amount of rainfall that your soil can store in the root area of plants. An easy way to understand this parameter is to think of how many regular summer days you would not water after a heavy rain. Default is set to 2 days. Colder climates can set to 3 or 4 days. Remember, this threshold (2 days, 3 days, etc) occurs only when heavy rain (0.25 inch or greater) accumulates in the ground.
Please note that it is not only the overall temperature that affects this property: Soil composition also affects the Field Capacity.