
One thing that annoyed [Jashua] to no end was hearing his automated sprinkler system kick on in the middle of the night, when it had rained earlier in the day. He wished that his sprinklers were a bit smarter, so he decided to give the system an upgrade.
Rather than pay hundreds of dollars for a more sophisticated automation system, he spent about $45 on supplies and scrounged together some items he had sitting around the house to make a rain-sensing module of his own.
The resulting project, Pysprinklers, uses Python along with a handful of components to better manage his water usage. He got his hands on a cheap rain gauge, and modified it with a game controller and a set of magnetic surface contacts. If there has been a significant amount of rain in the last 24 hours, his system will prevent the sprinklers from turning on. Additionally, if there is rain in the forecast, the sprinklers will be delayed a bit to see if rain makes its way into the area.
We’re all for saving money (and water), so we think [Jashua’s] system looks great, especially because he ended up using a handful of things he already had on hand.
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In my old home town, there was actually an ordinance against watering in the middle of the day, and watering the sidewalks. The local groundwater table was very low and the local farmers were on drought water rations.
Here in Sacramento, my stupid apartment complex waters at night, but 50-75% of the water is running down the storm drain, and I know of at least one sprinkler that’s been broken for months, gushing gallons right into the driveway.
While I don’t believe the hype about shrinking water supplies, in a relatively dry state it’s frustrating to see the waste.
Good job!
Link broken, 10/19/11 12:31 EST
If you live within the vicinity of anyone else that happens to be uploading their rain gauge data to wunderground, you could scrape their weather station data as a comma delimited file off the website. (ie. http://www.wunderground.com/weatherstation/WXDailyHistory.asp?ID=KCASACRA58&format=1 )
I believe you mean “wastes LESS water”
A much better solution is to landscape with vegetation appropriate to the local climate which does not need human-supplied water.
Pretty cool…I want one with a soil moisture sensor and RTC…. is it 0800? Is the soil dry? Water!
I’m pretty sure a sprinkler system that doesn’t waste water is kinda impossible…
depends, if it fed a population with nowhere else to get food i wouldtn call it a waste.
all depending on design of course
I recently saw a design for a solar powered still that circulates early morning air through buried underground pipes that are slightly slanted, creating a large amount of condensed water that’s collected in a plastic drinking fountain bottle. total cost is very low, and it uses next to no power, but it collects a great deal of water. Then that water can be applied directly to plant roots. (the two systems are installed at the same time)
Embed drip watering tubes (cheap to make at home but a little effort to install) and water only when a simple moisture sensor says to.
Rainbird makes a simple “sensor” to provide the required data. A plastic cup about the size of a shot glass faces skyward, supported by a stick up its middle and lifted by a small spring. When enough rain falls to matter, the cup gets heavy with water and compresses the spring. As it moves downward, a magnet attached to the cup approaches a reed switch which inhibits watering. The amount of evaporation which “empties” the cup approximates the evaporation time before the yard will again need watering, the magnet rises, the reed switch opens, and watering is enabled.
One moving part, zero power required for operation, no calibration, and surely under $5 to make. Some problems are more easily solved by thinking outside of the microprocessor box.
You need a microprocessor to check the forecast though.
This type of apparatus already exists. All four major irrigation manufacturers (Toro, Hunter, RainBird, and Irritrol) offer their own versions. Toro will be releasing a very simple, inexpensive, and universal wireless soil moisture sensor in 2012.
If you mispronounce Pysprinklers as piss sprinklers, you get a bonus funny mental image. (Yeah, I’m like 8.)