I have put in a request for an update.  It may take a few days to hear back from the sent message.  I will be happy to pass along anything that I can.

I guess if you were in a desert climate with a small load it would work great,. but so does thermal mass.
If you have 300 gal you would have app 200,000 btu of storage cap depending on what refrigerant they are using.
What am I missing? ....Eric

If a typical Geothermal unit uses 10 gallons a minute, it uses 300 gallons in only 30 minutes. I looked at the website, they give no indication where the tanks are stored, I assume in underground. I would think for this system to work, you would want the storage tanks to be large as possible, Two 10,000 gallon buried tanks would be more along the lines of what a typical residential install would need. (14 feet high and 11 feet in diameter) these run about $5,000 each. That would give you a 1000 minutes run time (16 hours). Considering the system isn't running all the time, (I'm guessing 1/3 the time during the hottest or coldest weather. it should give a good 2 days before you had to reverse the water flow. The install cost would be comparable to what trenching would cost you. Perhaps 10k is overkill, perhaps you can get away with 5k tanks, they only run 2k each. that would give you 500 minutes day run time,(24 hours before reverse flow) I would think that would be sufficient time to allow each tank to recover from heat gains or losses, and the install price would be well below trenching.

I was thinking, what if you installed the tanks one over the other and had a slow drain from the top tank to the lower tank. When the system was running it draw water from the bottom tank and discharge water into the top tank, than make the drain from the top tank only large enough to drain 2 gallons a minute into the bottom tank. So when the system was running for say 30 minutes it would draw 300 gallon out of the bottom tank, and only 60 gallons would drain back into the tank from the top tank. This would minimize the heat gain or loss mixing of your source and return. While the system is off the water will continue draining from the top tank to the bottom tank. Most of the time, by the time the system kicked back on the top tank will be empty again. I'm wondering if you could get away with a 5,000 gallon bottom tank and maybe a 1,000 gallon top tank.     

When I look at the BTU's involved I understand why the tanks should be large.  What I have heard so far is that the tanks are very modest in size and not buried.  Maybe later I can find out more precisely how this system operates.

I like the idea of one tank above another buried in the ground.  Would the top tank have to be vented just like the waste lines for a home for the drain to work properly? 

One concern that I have is whether the water will move around enough in the buried tank or tanks so conduction can occur.  I think turbulence in the tank will be needed so the water will not develop a boundary layer that insulates the interior water.

There is some validity to capturing outdoor cold during the night and heat during the day and storing it in water tanks (aka active thermal mass). A heat pump can be used to amplify the changes in temperature and reduce the amount of water needed - ie, run at night if the cold tank needs replenishing and in the day if the heat tank needs replenishing. In either case, store the hot and cold produced by the heat pump. If you get too much of either, dump it outside with some type of radiator (effectively an inefficient ASHP in this case) at the appropriate time.

That being said, I'm skeptical about the numbers working in the general case. And about lots of practical details.

Posted By Alton on 30 Jul 2010 02:05 PM

I like the idea of one tank above another buried in the ground.  Would the top tank have to be vented just like the waste lines for a home for the drain to work properly? 

One concern that I have is whether the water will move around enough in the buried tank or tanks so conduction can occur.  I think turbulence in the tank will be needed so the water will not develop a boundary layer that insulates the interior water.

Hmmm, in a sealed system, a line from the top of the bottom tank to the top of the top tank would allow the air from the bottom tank to be displaced into the top tank as it drains into it. Also I there would have to be an overflow line near the top of the top tank to the bottom that that doesn't have drainage restriction, just in case the system runs too long and completely fills the bottom tank. A 1,000 gallon top tank should give you 125 minutes of run time (at 10 gallons a minute) before overflowing.

As for turbulence, wouldn't the water draing from the top tank into the bottom one create that? Distilled water could be used in the system to prevent any deposit build ups that may corrode of clog the piping.

there would be no more need for distilled water than any other closed system. limiting make up water is the best way to eliminate calcium or lime buildup. Without some source of energy for the heat pump to extract this has a very limited application...Eric

I don't see this working for more than a day or two - In summer the tank would quickly become too hot and in winter it would cool to near freezing just as fast.

In a somewhat related vein, I do wonder if I could connect my system to a swimming pool - let it heat water during day and leave it uncovered at night during which it would cool via evaporation and convection as well as some conduction to ground. The cooling could be boosted by a fountain configured to come on if pool water exceeded 90 or so. Whether it could gain enough heat via ground conduction and solar gain to keep from freezing (in winter) in Florida is another question.

I calculate my system rejects about half a million btu on a really hot day. That would heat a 25000 gal pool about 2.5 deg*F. Would a 90*F  pool left uncovered in 75 deg*F late night outdoor air lose 2.5*F? before the next day's run added another 500k btu?

I know heat pump pool heaters are often sized in the 8-12 ton range, so I suspect I could make this work.

If I had a pool I'd try it, but I don't...

I heard today that my friend has not had a chance to try the new TRIEA system because the company keeps making changes and has not shipped units to dealers.  If and when this changes I will pass on what I can.

That sums up my experience as well.  The only difference is they say they're testing my unit before shipping... its running great, however, they have failed to ship after promising to ship each week for the past eight weeks.  There has been no cost yet but its frustrating when I have a test application waiting to install this thing and they leave me hanging.

PS. Generally, they're using 4-135 gallon tanks: hot, cold, neutral and potable hot water.

Posted By Jobbz on 02 Aug 2010 10:50 PM
That sums up my experience as well.  The only difference is they say they're testing my unit before shipping... its running great, however, they have failed to ship after promising to ship each week for the past eight weeks.  There has been no cost yet but its frustrating when I have a test application waiting to install this thing and they leave me hanging.

PS. Generally, they're using 4-135 gallon tanks: hot, cold, neutral and potable hot water.

I'd love to be a fly on the wall in that place. Are they having an "Oh, s***!" moment as they realize their system violates basic laws of physics, or are they laughing as they wait for the first checks to come in so they can take the money and run? Either way, please don't send them any money, and don't hold your breath waiting for a working unit.

There is no way storing heat in a 135 gallon tank of water has any but the most transient ( an hour or so) useful effect on a system meeting a typical residential heating or cooling load. Consider for example a nominal 3 ton system. Ignore effects of compressor heat of extraction or rejection and merely consider addition or subtraction of 36 kBtuh to / from a 135 gallon tank:

Raising or lowering the temperature of a 135 gal tank by 1 deg*F involves the exchange of 1125 btu. Moving 36 kBtuh to or from such a tank for an hour will result in its temperature change of 32*F. That's fine for the first hour - a 70*F tank of water is heated to 102*F or cooled to 38*F

What happens during the next hour? Raising the tank temp from 102 to 134*F by the addition of an additional 36000 Btu is a poor option owing to the significant increase in compressor discharge pressures likely to ensue. During heating season sucking another 36000 btu from a 135 gal tank of water at 38* would reduce its temp to 6*F, except that water freezes at 32*...clearly a non-starter.

What are these people thinking that we don't understand?

Engineer, I freely admit I do not understand how it will work. Maybe a coincidence or someone from the company is reading this thread but the unit shipped today with delivery tomorrow. Hopefully I'll have it installed and running early next week. More to come...

If you do a google-maps satellite view of their 7905 Kentbury Drive street address, you'll find it's in a nice residential area of Bethesda- hardly the sort of place you'd expect to see HVAC equipment being produced or tested. If you look a their 7625 Wisconsin Ave. address it's a mix of office,retail, & restaurant space, but nothing industrial enough to support an HVAC company. Web searches on the company turn up very little, other than they were established last year (2009)

Not that serious design folks can't work from fairly anonymous places, but I'm gonna go out on a limb here that it's a vapor-ware product from a vapor-ware company, most likely formed to try & milk federal subsidies(?). Or maybe cooking something up to scam some unwary investors(?). The concept appears brain-dead for handling any real loads, as anybody who can do the not-very-rocket-science arithmetic on the BTU flows can prove. (Curt- you forgot to add in the heat-of fusion BTUs that were derived from the freezing, and use the specific heat of water-ice as opposed to liquid water for the sub-freezing operation cycles. :-) ) Looking at their management team they appear to be long on the finiancial-engineering, and nearly bankrupt on the technology & design end:

http://www.trieasystems.com/management-team.php

At best it's a large-volume electric hybrid hot water heater with some hydronic air-heating/cooling coils attached. I'm dubious that it'll perform well enough for space heating & cooling in independent testing to qualify for any federal subsidy. If they're lucky they'll be roughly efficient as the GE hybrid HW heater.

Posted By engineer on 03 Aug 2010 12:33 AM

What are these people thinking that we don't understand?

It only works with water that's Structured™ and/or Micro-Clustered™.

http://www.youtube.com/watch?v=FAK9DnNGslo

http://www.youtube.com/watch?v=V2rQ1nSvZBU

...accept no substitutes!

Looby

"There are more fools than knaves in the world, else
the knaves would not have enough to live upon."
- Samuel Butler (1612-1680)