I have been doing some research on the Acadia cold weather heat pump and checking to see if anyone here knows about this.
The energy savings stated by the company (Hallowell International) are amazing.
I was told by Webbs that they were trying to get this in for stimulus money by calling it an advanced heat pump, because it is not considered geothermal.
Moe
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On just my quick review of the website, it is better if you live in Canada and So So south of the Mason Dixon Line.
When it is too cold Heat Pumps do not work as well, and so its extra booster helps it work better, not more economically. Geothermal works better cause it get supplemental heat from the ground.
Having had a commercial HP (air-air) for a number of years, deceided to go for a GSHP.
If you want 'advanced', IMO you need to design your own for your specific temperatures and resources.
Did my research, including remembering how to do Mollier diagrams from school and researched tube in tube HE for water to refrigerant.
Would be helpful if you filled in your profile - Ontario, Michagan, BC ??? and if you have room to dig trenches or can get water rights for a flowing well.
That said, are you handy? After looking at commercially available GSHPs, deceided they all made too many trade offs for a wider residential market and profitability. Best I saw from different mfg was a cop in the low 5's for mucho big bucks.
So designed my own. Finally used the condensor from a 30 YO 10 ton Carrier AC which got 'stuffed' into existing ductwork with booster squirrel cage, and made my own evaporator (3.4 Cu pipe inside 1-1/4" conduit) - all of whichwas 'free' surplus stuff.
Bought a 14 cubic meter/hr Copeland scroll compressor and refrigerant line filters - years ago did get a freon liscense as a 'grandfather, etc.'. Made own controls from parts laying about (Furnas contactor, built a few circuit boards with $15 worth of parts from Mouser, etc). Have own backhoe and drilling rig so that part no cost except time - which is another story...
Using it this winter, for less than $600 out of pocket costs, heats 5300 sq ft 1970's house in seattle area (55F ground temp in winter 8 feet down) for about $3.50 per day in January (at 10cent kW-hr, have a dedicated kW-hr meter on the HP) COP - measured - is 5.6. Figure it will have paid for itself in power savings by next Dec., just put it in last October.
Looked at rthe Acacia web site, their efficiencies (200 to 400%) are basically COP times 100. Most commercial air-air HPs meet those numbers. My old air-air Rheem (which comes on in lieu of the GSHP only when outdoor air temp is over 50F) has a COP of 3.5 at 47F (350%) but that drops to 2.3 or so at 17F which is colder than it has been here for 30 years.
Have fun.
BTW, probably cannot suck any $$ out of 'bama or the POCO and the group for DIY GSHP, even if better than commercial <G> Pretty sure you need and ARI rating for rebates also.
Edited 4/14/2009 8:18 pm ET by junkhound
The Acadia unit is not geothermal, or even a ground source heat pump. It's an air source heat pump. I think they have extra compressors or something to make it work at lower temperatures than regular air source heat pumps. Our HVAC guy has installed some here in Maine and says they don't quite perform as advertised. I haven't seen one in action myself.