The good folks over at Spark have posted on their blog how to make a Nest at home for $70! How can this be you ask, I just spent $250 on one! Well its going to take a little elbow grease, some scrap wood and a few goodies from Spark. They milled out the wood for the shell and dial and clear acrylic for the screen. The tasty bits inside include: a Spark Core for the brains, an adafruit 8×8 LED matrix for the display, a Honeywell Humidicon for temp and humidity and a Panasonic PIR motion sensor. All told, it took three of them 16 or so hours to complete it.
How would you quantify one being better than the other you ask? You could look at overall cost, set up time, user interface and temp/humidity variance specs. Cost was a complete blowout in favor of the open source Nest, $70 compared to $250. Setup time swung in favor of the Nest, 10min vs. 16hrs! Next up we looked at the interface and ease of use. The LED display on the open source Nest displays the temp nice and big but there is no denying the Original Nest’s clean and legible display and UI. Lastly, temp and humidity variance.
Whether you’re taking the time to build one yourself or just want the latest gadget, you want the best you can afford. The open source Nest uses a Honeywell Humidicon good for plus or minus 4% RH across all bands. The Original Nest uses a Sensirion SHT20 accurate to plus or minus 4.5% RH. Could you build a better Nest for $70? I suppose you could, but not by much.