I'm curious how this batteryless technology is supposed to work. Without a secondary source of power you're really just playing the idle game with electronics. Is there secondary power (small wind turbine using the HVAC breeze?)
Seebeck generator, I assume. Basically stick two different types of metals together and generate electricity when the temperature changes (i.e. every time the central air kicks on and off)
Not when the A/C turns on and off, but rather the entire time it is running. The hot side would be exposed to the room, cold side to the duct (and vice versa when heating).
I'm not 100% clear on what you are describing but I'll take a stab. I think you are saying that in order to have a similar 'microzoning' concept, an alternative might be 3 Nests and 3 corresponding compressors.
As a retrofit (say, 1 compressor -> 3 compressors [would probably have to ditch the original], ducting changes and 2 additional nests [assuming you already have one]), I would say flair will be more economical. That being said, even if you had a 'large' home with 3 nests and 3 compressors, it is still going to have N rooms corresponding to a single thermostat hence opportunity for efficiency gains and comfort improvement.
while flair is a distributed thermostat, it builds on top of Nest in a complementary fashion rather than competing with it.
Very interesting, but it doesn't look like it'd work too well with floor vents (stubbed toes and the like, not to mention durability in case someone or even a pet steps on it). Any chance you're already looking at the problem?
yes. the prototype in the video is a fairly early physical form factor that is tailored to a popular vent size. Vent sizes come in a wide variety of form factors (shapes, sizes, materials and mount locations) and we are working on covering (pun intended) the more popular sizes for both floors, walls and ceilings. We have a few tricks up our sleeves around the form factor but (similar to our 'batterylessness' concept), we are keeping those close to our sides until we are a bit further along.
Many times the actual cutout in drywall is smaller than the "vent" cover, which is mostly for aesthetics. So of course you can make a vent cover two feet long with only the center 50% being the actual vent and the rest being a thin plate that simply sits on the wall and hides the screw holes.
Why would floor vents be a problem? Existing, manual dampers in floor vents often have the moving parts recessed below floor level. The one extra issue might be increased chance of spilling liquids on the unit.
The prototype appears to mount on top of existing vents and the dampers are also fully exposed room-side. A device that's sticking up an inch from the floor rather than being flush is going to have problems, whether it's tripping or stubbing your toes over it (and dislodging it by doing so) or just damaging the dampers by accidentally stepping on it. That said, I imagine that it's pretty likely that they'll have a solution for it when they get to market.
Small nit: the website uses a <video> element and only provides an Ogg Theora video. This means that the video isn't visible in Safari on OS X and iOS, or in Internet Explorer on Windows. In Safari on OS X this results in an empty set of controls being visible for the video element. In Safari on iOS I see a non-functional play button where the video would be. Furthermore, since the <source> element doesn't have a type attribute browsers have no way of knowing up front that they can't play the video and are forced to start loading the video to determine if it's playable.
@bdash Sorry for the delay; we had a whole bunch of meetings in the past few days. The video plays on Safari on OSX and iOS and IE on Windows. Thanks for reporting the issues :)!
This is cool tech but I wonder about the efficiency claims. Depending upon how the HVAC system is designed, where vents are located and where return air is located, you could cause the HVAC system to run less efficiently if you alter the air flow through the home.
HVAC controls most work as a team, otherwise they end up fighting each other.
As a simple example, picture an office building in which each room has a temperature sensor and air supply.
If a room says "Oh, it's hot here!" The system will try to send cooler air.
Now, imagine that in one of those rooms, there's a little lady who's a little cold. The system however, is in cooling mode, because the room is slightly warmer than the temperature setpoint.
The lady won't have it a decides to bring an electric heater. Now she is heating her room and feels more comfortable. From the point of view of the system, her room is much warmer than it should be. As a consequence, the system sends even more cooler air to her room.
The lady now has to crank up her electric heater to counteract this increase in cooler air...
There are quite a bit of assumptions to counter here but the first most basic one is that this is intended for office buildings. It is intended primarily at residential after market energy efficiency and comfort retrofits. I
Relating your heater example. This applies to current systems even. You plug in an electric heater under your thermostat and its working to cool while you are heating...you simply wouldnt do that.
100% agreed on mileage varying. We are building it to treat the on-time of the system as our cost function with requirements around satisfying temperature (and humidity) levels. We know that in some homes the return location, duct leakage and numerous other scenarios can cause efficiency gain impedements. But as long as we are tracking how much time the system is on for, respecting the blower motor (pressure sensors) and satisfying the user requirements for occupied (and unoccupied) rooms, we can at least gaurentee an improvement of 0 or greater %. In most cases, the gains are very substantive as the returns generally tend to be in larger open rooms or hallways. Tracking is a key component to our system.
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[ 1.4 ms ] story [ 56.8 ms ] threadIf your work isn't ready for people to try out yet, [...] please don't put "Show HN" in the title. Once it's ready, come back and share it then.
https://news.ycombinator.com/showhn.html
As a retrofit (say, 1 compressor -> 3 compressors [would probably have to ditch the original], ducting changes and 2 additional nests [assuming you already have one]), I would say flair will be more economical. That being said, even if you had a 'large' home with 3 nests and 3 compressors, it is still going to have N rooms corresponding to a single thermostat hence opportunity for efficiency gains and comfort improvement.
while flair is a distributed thermostat, it builds on top of Nest in a complementary fashion rather than competing with it.
HVAC controls most work as a team, otherwise they end up fighting each other.
As a simple example, picture an office building in which each room has a temperature sensor and air supply.
If a room says "Oh, it's hot here!" The system will try to send cooler air.
Now, imagine that in one of those rooms, there's a little lady who's a little cold. The system however, is in cooling mode, because the room is slightly warmer than the temperature setpoint.
The lady won't have it a decides to bring an electric heater. Now she is heating her room and feels more comfortable. From the point of view of the system, her room is much warmer than it should be. As a consequence, the system sends even more cooler air to her room.
The lady now has to crank up her electric heater to counteract this increase in cooler air...
Relating your heater example. This applies to current systems even. You plug in an electric heater under your thermostat and its working to cool while you are heating...you simply wouldnt do that.