Tool Development Diary: Wireless greenhouse monitor
I have run my own farm for eight years, but because I have always farmed rented land, I have never lived within two miles of any of my greenhouses. That means that I have had a lot of restless nights, wondering if my seedlings were alright. Fortunately, a few collaborators and I recently received a grant that will help us to develop to new tool to solve this problem.
Over the next few months, I will use the Farm Hack blog to document our progress as we brainstorm, prototype, test and tweak the tool that we have come up with.
CSA vegetable farmers like me have a lot at stake in our seedling greenhouses– tens of thousands of plants, which we depend on for a productive season. If it gets too hot, or too cold, a die-off in the greenhouse can have a devastating impact on the farm’s bottom line. I can’t count the number of times that I have driven several miles from my home to my greenhouse just to check the temperature, sometimes at 1am on a cold night, or at 1pm on a hot afternoon. 95 percent of the time, everything is fine: the heater is fired up and keeping things warm; or the fans on thermostats are working properly and venting out the heat. A waste of a trip, except that without going to check on the seedlings, I probably wouldn’t have been able to fall back asleep.
There are alarms that farmers can buy and install in their greenhouses to monitor temperature. Some of them just sound a siren if things get too hot or cold. Others hook into a land line, or an internet connection, to call a farmer with a temperature alert. None of those were going to work for me, since my greenhouses aren’t near a land line or an internet connection, and they are miles away from earshot. This situation is common to a lot of young farmers who are growing on leased land.
An idea for a solution
At Farm Hack New Hampshire last fall, we had a working group on “smart farm” tools. We were lucky to have both farmers in the group, as well as some allies with skills in open source software and hardware development. I joined the group to discuss how farmers might use sensors, open-source circuit boards, and computer code to create DIY tools that could make our farms more efficient and more sustainable. We threw around lots of ideas, some crazier than others. One project that seemed straightforward and useful was creating a farm-built greenhouse monitor that could deal with any problems that might come up. We knew that the possibilities for this were wide open: it could monitor soil moisture and turn on sprinklers, or temperature and send turn on fans, all while collecting data that could allow the user to monitor the temperature trends in the greenhouse over the day.
We wanted to make the first attempt at this tool simple and useful, so we decided to tackle the problem outlined above. We wanted a greenhouse monitor, built from easily accessible parts by a farmer without major electronics skills, that would send a SMS text message to a farmer if there was an “alert” situation in the greenhouse, or that would just send regular status messages about the state of the greenhouse. We decided we’d also like to make the communication two-way, so that the farmer could text the greenhouse and get a response with the current temperature. We knew that many farmers didn’t have a landline or internet access at their greenhouses, so we wanted our tool to operate using cellular networks to communicate. And it would have to be cheap enough to appeal to cheapskate farmers!
Applying for a grant
A subset of our team set out to apply for a grant to fund the development of this tool so we could build it, document it, and share it with the farmer community at large. RJ and Louis (open-source computer programmers and hardware developers) joined up with me (Ben, vegetable farmer) to apply for a USDA Sustainable Agriculture Research and Education (“SARE”) Farmer grant, which funds farmers to carry out research and share it with other farmers.
We just learned this week that we got the grant! So we are excited to spend a chunk of time this spring putting together a prototype of this tool, getting some other farmers to test it, and documenting the whole process to share with the world. This is the first step, and you can keep tabs on the project as we go forward right here at Farm Hack.