I built a duel purpose
greenhouse. It dries my
firewood out like a champ. And I keep figs and tomato plants in there to extend the season.
It's 12 1/2 x 28 feet. I will build another one similar to that next year.
Temperature management in a hoophouse or
greenhouse is a big deal for most things that you would want to do in a greenhouse.
I have tried different thermometers that record high and low. They work, but there's no real data logging, etc.
I got excited when I saw a temp logger that they were using in one of the Wofatis.
I hunted them down, and also found a much cheaper version on ebay.
They are $14 shipped. They can record 32,000 data points, at whatever interval you want. I have mine record every ten minutes. It will run for 6 months on one wafer cell.
http://www.ebay.com/itm/Mini-Waterproof-USB-Temperature-Data-Logger-RC-5-Recorder-32000-Points-Sensor-/381421977427?hash=item58ce857f53:g:2V0AAOSw9r1WC62B
You have to download some software to use it, but it's free and works pretty much straightforward.
It's starts downloading automatically if you put this in your address box:
http://www.e-elitech.com/uploads/soft/software/RC-4&5_Conventional.exe
It is 60 megs, which kind of surprised me, but hey, it works.