The threat of Day Zero in Cape Town (South Africa) has made the citizens aware of the value of water. Together they managed to reduce average water consumption by more than 50 %. Throughout the world, the climate change will make water a rare good in areas where it used to be taken for granted. With smart irrigation systems, water consumption can be monitored and probably even reduced. I want to show you the success factors in your area of application, and recommend what I believe to be the best technologies.
Irrigation for Agriculture
For irrigation of large areas, feasible features are mostly limited to monitoring. However, viticulture and fruit cultivation are an exception to the rule as active irrigation is often put to use here.
Agricultural irrigation is pretty unique because, for a change, usability does not take priority. Instead, stability and reliability are key to a successful agricultural irrigation system. Failures and errors need to be reported as they occur, and predictive maintenance needs to ensure smooth operation.
Which wireless technology should be used?
For monitoring, I recommend LoraWAN. Its base station is reasonably priced and able to cover a huge area. However, as I would not rely on the security features implemented in LoraWAN, I advise against using it to control water valves, and would instead employ it for sensor data collection only. Due to the high setup/installation costs, wired connections are not feasible for wide areas either.
Irrigation for Homes
Traditional irrigation computers are a bit outdated. The phrase "Everything is better with Bluetooth or an app" might be a running joke, but there is a point to it. If you compare those ancient irrigation computers to modern studies of usability, it quickly becomes clear that they leave much to be desired. The interaction with or setup of residential irrigation systems is mostly done once a year, probably at the beginning of the summer period. An easy setup is crucial as we are not dealing with the everyday "I use my app and turn the water on and off" situation. The setup is also what makes the first impression, and the first impression counts. After all, it defines the product review on Amazon and the like.
What should a smart irrigation computer be capable of?
First of all, a smart irrigation computer must be able to control water valves. I know, you're probably like "Duh, you don't say" now. But bear with me. The computer needs to offer a simple way to turn the water valves on and off manually. Yep, I'm not talking about controlling them with an app. Instead, I suggest a good old button for each valve. Next, rules are needed for automatic irrigation. Here, the irrigation computer needs to take several pieces of information into consideration: weather forecast, sensor data, astronomical data (e.g. sunrise, sunset) and more. Sensors might include the obvious choices, i.e. sensors for moisture, temperature and light, but they could also include water meters to measure the total amount of water a specific area or a single plant has received.
It's all about usability, stupid!
Back to the easy setup: the user needs clear guidance on how to set up rules to automatize irrigation. I'm not talking about a blog, or FAQ. The app needs to suggest rules and indicate which rules should be used for which circumstances.
The smart irrigation computer is nothing but a box if it cannot control the water flow. Since most homes don't come with preinstalled or wired water valves, there are three options:
- permanently installed valves with a wired connection,
- permanently installed valves with a wireless connection, and
- wireless valves that are attached to the water tap.
As the first two options require a plumper to install the system, they do not exactly offer the easiest setup possible. I would therefore resort to the wireless valves attached to the tap, although I am open to a more elegant solution. The important thing when coming up with ideas is to always have an easy setup in mind.
Which wireless technology should I use?
Bluetooth 5.0: The latest Bluetooth includes mesh capabilities and has the cheapest SoCs. The technology is widely used, and some sensors are even standardized, so you can easily use third party devices.
ZigBee: Here, you have a system that is already common in the lighting and home automation sector. The ZigBee profiles can be extended to fit your application. What is more, the latest SoCs from various vendors support dual stack Bluetooth and ZigBee simultaneously.
6LowPAN: this is also the technology behind ZigBee, but by using just the basic communication layer you can define your own application layer and make sure your customers buy your products only.
Irrigation for Greenhouses
Well, this is a special case and depends on the size of the greenhouse. When it comes to greenhouse irrigation, you can basically create an environment completely set apart from the "real" environment outside the greenhouse. That's what greenhouses are made for, right? So the irrigation computer does not only need to turn the water valves on and off, but also control the temperature. This includes heating, ventilation, and also shading. To accelerate growth, lighting might also be controlled. By optimizing the efficiency of the entire environment, you can save water, electricity, and much more.
Regarding technology, you might want to consider combining agricultural and residential irrigation technology. The valves can be wired to a control unit akin to a DIN mounted PLC that also includes ZigBee to control light, shading, and heating. This would save wiring/setup costs.
A camera that captures the plants' "greenness" would provide better feedback of the condition of the plants. This might reduce water consumption to a minimum while keeping the plants healthy. Of course, the command would have to be more than just "brown → turn water on" and "green → turn water off". The feedback loop would be too slow. For this idea to become reality, more intelligent algorithms are be needed.
Get the nymea irrigation test package containing an irrigation computer with several wireless sensors and actuators.
If you wanna learn more about nymea for irrigation, check out our Irrigation Systems verticals section.