Monitoring a farm

Me and my girlfriend are planning on moving to a farm next year, and become self sufficient.

I’m a geek at heart and would love to monitor the whole farm in terms of temperature (air and ground/soil), rainfall, humidity, wind etc etc.

I think I’ve decided on a DreamPlug as a server (since our plan is to be self sufficient in energy, we need to conserve). Coding the bits that receive data and stores it in a database (and then creates graphs/information from the data) is not a problem.

My current idea is to have small boxes all covering the whole farm (maybe 10-15 of them). I envision them waking up once every 10-60 mins (not sure on interval yet), take a few readings, sending it to the server (ZigBee?) and fall back to sleep. The energy would come from solar panels (maybe with a battery backup).

We’re based in Sweden, so temperature will be between -35 and +40 (in direct sunlight) celsius. We also have snow, if that wasn’t obvious from the temperature :wink:

How realistic is it to build such a grid/system? Especially one that will survive the weather, since we won’t be able to afford to replace a few every year…

Any and all pointers/ideas/suggestions/ready blueprints are welcome!

The first big variable is communication range. If you can get them to communicate, I would say the only other issue you would have is enduring the weather. Also, if the stations are close enough together to communicate, I'm thinking you may only need one temperature and humidity sensor, unless I'm missing something? As far as ground temp, I would imaging it wouldn't be too hard to find a controller for an external thermal probe, that you could just stuff in the ground, and have a wire going up to the transmission tower (I'm assuming you're mounting these on a tower to facilitate communication?). As far as battling the elements, I think the easiest way you're going to find, is to use the equivalent of an adjustable solar oven- In the winter, even though the air temperature is cold, you can still capture the sun's rays as heat. Of course, this would literally cook the components in summer, so you would also need to add in a shield that could be rotated over the unit to reflect the sun's rays, similar to an umbrella. I think the easiest way to do this, would be to make the container that will hold the electronics, then have a stepper motor shaft exposed on one side, and just have a shield attached to it. That way when it gets to a set temperature, you just have the shield come down over the box, and it's now in shade.

This may be of intrest to you...

In the winter, even though the air temperature is cold, you can still capture the sun’s rays as heat.

Well… this has it’s limitations… not that it isn’t a good idea, but without knowing where exactly in Sweden this will be used, we can’t say for sure. Remember, parts of Sweden have a month long night. Although it would compensate in the summer.

I’ve been thinking about something similar… not for my farm, but for my retirement home in about 30 years (LOL) where I envisioned using a ATmega2313 or smaller connected to an XBee getting readings of different sensors (mainly temperature and humidity, but with a modular design to be more flexible). I then found an article (guess on Lady Ada’s website), about using the XBee peripherals. I’m yet to buy ones to test this out, but it could really simplify the design… although, if there’s no possibility to put them to sleep, it’s probably best to have a microcontroller that starts up the XBee when it wants to transmit to save power.

Give it a try. As long as you use analog sensors, it’ll work… maybe not in a power efficient way, but it’ll work.

But like I said… it is still very very green as I still have 30 years to go and technology evolves too much. LOL