Last year, I was living in a house with several people much, much fatter than myself. The living room was upstairs, where the heat collected. My studio was downstairs, partially buried in the ground, which sucked all the heat away. There were heated arguments over the thermostat settings.
Eventually these arguments resulted in a housemate trying to solve the problem by installing a "fancy" new thermostat downstairs - it was a programmable monstrosity with a completely unintuitive LCD display. To this day I am never sure if I ever actually managed to change the temperature it was trying to maintain, or merely dinked around with specifying a temperature that would have taken effect IF I'd put it into the program.
There was probably a manual but I really wanted to talk with the housemates as little as possible to find out where the hell it ended up being stored. I have written fricking 6805 assembly code, I am not technologically incompetent by any means, but I sure as hell couldn't be bothered to try to deduce this thing's operations from first principles.
(Arguably this means the thing did exactly what they hoped it would - make me quit bitching and put on a couple sweaters instead of maintaining a shirtsleeve environment comfortable for a skinny chick in a house largely full of 300lb folks. But I digress.)
> A real thermal management system for the home does not start with a high-design thermostat on the wall. You need multiple types of sensors in every room and multiple outdoor points.
Well, let's see: a Nest has an activity sensor, temprature, humidity, and an Internet connection, which means it can find out what the weather's like outside. Plant one of these in every room and you've got something starting to happen, if you're using local heaters rather than a central system. Admittedly you won't be doing this yet until they get the price down.
> As far as control, a very simple embedded PC board running embedded Linux would be the "lazy" way to build it. It would actually be overkill, but there's an argument to be made for the COGS aspect of it.
Care to lay wagers on what's inside the Nest? I'm betting it's exactly that. You may be willing to spend the time and money to get the thing going and write software for it. But there are a lot of people out there who are not. This is a really attractively simple version of that.
You're describing a level of commitment akin to "I compile my Linux kernels from scratch", this is for the "I open my Mac and it just works" crowd.