The opportunity to mix *really* old technology with the latest IoT is the kind of project we love doing, not least because you get to hang spend time with other passionate geeks and often in beautiful locations.
Over the past few months we’ve been quietly working on just such a project, and this week Mike and I headed off to do the installation at Woodbridge Tide Mill, a working mill and museum located by the River Deben on the coastal fringe of Suffolk.
I was introduced to Ian at the mill by the Suffolk County Council team back in March. Suffolk has been deploying a LoRaWAN network across the county for the past few years. They use it themselves for things like monitoring meeting room occupancy and smart streetlights, and they also make it available to local businesses, community groups and other organisations in the region.
Woodbridge Tide Mill was one of the first to be running in the country and one of only a handful still working. The current mill will be a spritely 230 years old next year, but records show that a tide mill has been producing flour on the same site for the last 850 years. A fine example of renewable energy in action.
For me, there is a nice link to another of our customers – the much (much!) younger Reading Hydro, a community project on the River Thames here in Reading. It uses the renewable energy of the river flow to generate electricity, and we have festooned the site with sensors and helped get the data out of the turbine room and onto the internet.
Reading Hydro uses state of the art metal screws that are turned by the flow of the river to generate electricity. But it’s been a dry summer and we’re waiting for rain before it can start generating again.
The rise and fall of the tide is both reliable and predictable, and it is this movement that is used in Woodbridge. As the tide rises a walled pool fills with water. Around low tide the water is released from the pool through a channel with a huge wooden wheel in it, which rotates as the pool water flows back to the sea.
Visitors who time it right get to see this first hand, and it is well worth visiting the mill and museum. It is staffed and operated by a group of friendly volunteers, who are very knowledgeable, and there are excellent interactive displays and audio panels which do a great job of bringing the science and the history of the mill to life.
The team at the mill wanted to use data from sensors to create a number of educational resources, looking at the environment inside and outside the mill, and to gather some useful information on footfall.
Woodbridge is covered by the council’s LoRaWAN network, which meant we could take advantage of the long range of the wireless and use battery powered sensors that run for years before the batteries need changing. This removed several installation and maintenance headaches that would have otherwise affected the viability of the project.
Of course there was still plenty of head scratching as Mike and I worked through the various challenges, such as how we could get a water temperature probe into the middle of a steeply banked pond that fills and empties daily, make sure it stays in position, and that the data can get from the pond onto a dashboard. And how to stop ourselves from falling in!
Here you can see some of the sensors we installed and even a couple of action shots:
The sensors send their data to a dashboard via a private instance of The Things Stack. The dashboard presents a “live” status of the sensors, which will be displayed on a screen inside the Mill.
We also provide a full set of charts showing historic data that will allow the mill team to monitor changes over time. This will be a useful resource for some of the education activities and events that the team runs.
It was wonderful to see so much enthusiasm from all involved at the mill – everyone from the Treasurer to the Wardens, to the Social Media guy were interested in the project and took notes so they could explain the purpose of the sensors to other colleagues and of course, visitors to the mill.
I think the best projects are where all parties come out of it having learned from each other and made new discoveries together. This project has been a brilliant experience for us, provides valuable information to the mill team, and will underpin some new educational material for students visiting the mill over the coming years. And it was made possible because of the strategic investment in a LoRaWAN network by Suffolk County Council.