I have been a long-time lurker of the forum, since the summer when I decided to retrofit my newly-purchased home with a GSHP system.  Some of the recent comments about expectations and new owners prompted this post idea.

When I was researching whether or not to spend the $26,000 on a new system, the data I found hardest to obtain were real-life experiences from other GSHP owners.  My biggest concerns at the time was the investment and performance.  Does it work, and how long will it take to pay off?

So I thought I would throw up my GSHP situation and profile, and a few notes from a layman's point of view.  I hope that others might be inspired to do the same (in layman's lingo), so that folks looking for information on GSHP will have a good selection of information to compare with their personal situations.  It's the kind of information I wish I had when I was first looking.

We moved in to our place in May of 2008, so everything about the house and its quirks were completely new and unknown.  The biggest question mark ws how much oil would it take to heat over the winter.

Our place:

• Location: Fingerlakes region (upstate New York)
  
• 3,800 square foot contemporary log cabin, designed by Lincoln Logs, constructed in 1988;
• Basement and garage under the main living areas;
• The full front and part of the back of the house are sliding glass doors (LOTS of windows), triple-paned but original to the house (turns out they're very drafty, and slated for replacement this summer);
• The house is open and catches lots of wind (so much so that we inherited a windmill with the property);
  
• Heating options when purchased: woodstove in the main room and an oil-burning furnace (original to the house), with three 275-gallon fuel oil tanks (all empty);
• Furnace heated the house by forced hot air, basement heated, but not garage, single zone (one thermostat);
• Water was (and still is) heated by gas;
  
• No a/c in the house;
  
• The previous owners heated with wood, so while the furnace fired up for the home inspection, its life expectancy and efficiency were uncertain;
• Plenty of land for laying loops.

We have no idea what it would have cost us to heat the house with fuel oil; I can only make a very rough guess.  I would have filled the tanks probably in mid-September when the weather started to turn, so for 2008/2009 winter would have spent about $5,000 for 1,200 gallons of fuel oil.

Our GSHP system:

• Florida Heat Pump Aquarius EC-096 with extended range option (8-ton, basically a small commercial unit);
• Eight U-shaped horizontal ground loops, totaling 4,000 feet, in 6 foot deep trenches;
• Total cost (including installation) just over $26,000.
  

General observations:

• We usually keep our house at 67 during the day, and 65 at night;
• The furnace kicks on when the temp drops two degrees below the set temperature;
  
• Someone has been at home during weekdays, so the temp is programmed to stay up from 7am to 11pm;
  
• I've been monitoring my electric usage on a daily basis.  So far, our GSHP uses an average of $4.65 per day to keep the house warm (75 days to date);
• Since November, we've spent about $350 on electric for the GSHP ($0.08/kwh);
• If the outside temp goes below 20 degrees the furnace stays on.  It may or may not go into stage 2 depending on how cold it is, and if the sun comes out (I get good warming through our now-caulked doors and windows);

• On colder days, it may take most of the morning to go from 63 degrees to 68 degrees (roughly a one degree rise per hour);
• After the heat pump goes off, I believe that my loop fluid temp currently hovers at around 40 degrees (had problems with my thermometer when I read it and haven't replaced it);
• Our system moves a lot of air, so is noisier than I anticipated;
  
• On super-cold days, I fire up my woodstove for ambiance and to give the furnace a an assist.  A small fire keeps the house at 70 with the furnace coming on maybe once an hour, for about 30 minutes, with the outside temp in the low teens.

Updated June 11, 2009

• We had 182 heating days this winter (10/15 - 4/17), and I calculate the heating cost at an average of $4.66 per day.  We spent about $850 for heating for the winter, at $0.09/kwh (power cost and delivery fees). 
  
• We used 6 face cord of wood (at $55/fc) to supplement on the very cold days, and for winter ambiance.  (I count the wood as a wash -- we would have used about the same amount for the same reasons had we stuck with oil - I really like the wood stove ambiance.  :-)
• Next year's costs I hope will be even lower -- our loop field settled significantly this spring, so we should now have very good compaction.  Plus we'll have our drafty doors sealed properly.
  

The bottom line:

• If fuel oil prices stay high, and factoring in the 2008 tax credit, our system will pay for itself in under 7 years (I'm re-evaluating that annually to capture current oil prices.)  If I assume that we would have had to replace the old furnace, drop that down to 5 years.
• There's no real way to quantify value-add to the real estate, but in the very least the added a/c should be a plus.  Having a/c was not a priority for us at all, but I'm sure that it will be a nice-to-have when it gets hot and humid this summer.
  

The technology works as advertised, and with our wood stove to supplement (and act as the emergency heat backup during power outages), I feel I have a perfect heating situation.  Add to that the significantly lower environmental impact the GSHP has, and I couldn't be happier with deciding to retrofit to a GSHP.  The absolute single thing I like least is the air noise, so I may be investigating ductwork changes to see if we can reduce that.

I think that covers the questions that I searched for in the summer.  If other potential GSHP owners have additional questions, let me know.  Again, I hope other GSHP owners will join in and share your profiles as well.

Shelley

Shelly, thanks so much for posting. This is the kind of feedback that will help others to feel OK about making the switch to geo. I am going to suggest to the admin that your post be pinned to the top of the forum so it will not get lost in the jungle.

Shelley,

Well written - Well said.

You mentioned $4.65 per day, but what is this in Kilowatt hours per day?

$4.65 / $.08 = 58 KWH / day

To supplement, since mid-November a per-day usage:

Minimum: 13 kwh
Maximum:  112 kwh
Median:  54 kwh

During the bitter cold days, I burned wood.  Had I not, the max probably would be higher.

Shelley

I would be suprised if duct system was sized for 8 tons without modification, so I think you might be on to something.
J

I'll update if and when I tackle that bugaboo, and also update on total winter heating costs at the end of the season.  I expect they'll start to rise as we pull more heat from the ground.

Still nothing close to the cost of oil, though!

Great post Shelly!!
I assume the HVAC folks did a manuel J? How did they come up with EIGHT tons?? That's only 475sf per ton.

I know our installer did a manual J, but don't recall at this point the specifics. Initially, they were looking at 10 tons (two 5 units), which he modified after he did the visual inspection. Log-built homes apparently mess with everyone's R-value estimates.

Given the state of our doors (the windward side of the house is 90% sliding glass doors), I'm glad we do have the 8 ton. A smaller unit would not have handled this winter well, and we would have ended up horribly disappointed by the tech, I think. Once we get new, weather-tight doors, if we end up over-sized then so be it. I'd rather have too much oompf than too little.

Hi Shelly,

Great post. Like you, I had trouble finding real people stating they like their GSHP system. I also found that local prices were way out of whack with any formal case studies out there. I hung in there and did some shopping. I am now the proud owner of two 3-ton Climate Master Tranquility 27 units. Rather than ground loops, we opted to go with a standing column well (actually, two of them). Our systems have been operational since October '08 and we couldn't be happier. We just recently received occupancy, so I'll have to wait for some realistic energy usage figures.

Regards,
Ed
http://www.GouinGreen.com

I hope you (and others!) contribute detailed specs to the thread as well.  I know there are many owners out there (happy or not); the more information the better!

shelly

thanks for the post i have gotton some good info out of you pertaining to this new way to heat and cool. the biggest thing i have to look at is can i get return for my investment. at 26,000 to 50k i cant justify it as with interest paid on top of the install it comes out very expensive compared to fossil. now if i can do most of the work myself and get the rebates then i am in good shape. after my inspection it seems i can get by with a 5 ton unit to heat our home.

i am seeing here figures of 80 to 100 bux a month for heat and a/c i can handle that as propane is 2.13 a gal here and no doubt headed higher as el. is of course also. i burn wood but that is lots of work and dirty to burn plus the danger of burning your house down. it happens believe me! my son burns propane exculusvely and he will go through a thousand gal. this winter big bux to me! i am excited to get started on this system as soon as it warms up.

thanks

bob

I would be careful about comparing $$ spend per month. I would compare KWhrs or gallons etc. If you compare fuel or electric prices they can vary up to 200% in different areas of the county (i.e. electricity costs anywhere between 5 cents and 20 cents per KWh depending on where you live). So I've found the best method is to compare gallons or KWh.

My HVAC installer just came out for a mid-winter look-see. Based on our conversation, this was a worst-case scenario for our install; the coldest winter in a while, and I had the least compaction around my loops that I will have going forward. My incoming loop temp is 35 degrees, but I'm still on target for a 5-year payback -- based on 9/2008 prices. We'll have to see how far fuel rises again for next winter.

In my opinion, wood is an excellent backup heat for GSHP (any utility-based heating, actually). In our area, losing power to an ice storm for a day or seven isn't unheard of, and having a woodstove (properly maintained) has been a huge peace of mind. Keeps you warm, and you can cook all of the food that's trying to thaw in your fridge.

Good luck with your project!

Shelly, thanks for the update. So you paid to have your system installed and are on track for a 5 year pay back. This is great info.

Great info, thanks.

You have only 4000 ft of pipe for an 8 ton unit?

Yep - that's what my invoice says.

I am located in Western New York, not far from the Finger Lakes region. Two years ago I put in a Waterfurnace system, replacing a York air-exchange system I first installed when I built my house 27 years ago. The York system was working, but I decided to switch while not under duress. My costs were approximately: $8000 GSHP $4000 TWO wells $1100 earthwork, pipe $700 custom tinwork $440 plumbing $800 well pump My house is 2550 sq feet. The last four months I have paid an average of about $288 @ 0.146 /kWh. The house is 65 when people are home. 58 at night, and 60 during the day when people come and go. I have four kids, all teenagers. I have had two failures. The first was an early failure of the well pump (impeller failure) and cost $160 for the well driller to pull it and replace it. The rest was covered by the supplier. The second failure was of the circ pump for the DHW. It turned slowly at system initialization, and eventually failed. Replaced under warranty, but $160 house call (go figure, is this the industry norm??). It's nice heating the water with heat from a hot house in the summer. Since the unit is sized for the heatload, it cools off quickly when we get home summer evenings. The house is a contemp. colonial, and has a fairly large area of windows, without drapes. I didn't spend $26K, but I did spend a fair amount. I cannot tell what the payback time is, as numbers have changed from when I made the buy decision.

Bird, how many tons do you have? How deep are your wells? It sounds like you got a great deal on your geo. Wow!....I'm glad I'm where I'm at....our kw is about half of yours. I don't have geo now but plan to in the future.

I have a Waterfurnace p048, which is nominally 4 tons.  The supply well is 60ft, and was rated 35gpm.  The destination well is about 32 ft. (old milkhouse well).

I actually built a drywell for the  destination (large pit, with rocks from hedgerows, and landscpe fabric over it.  I decided to use the well instead, but have plastic piping going to the drywell, should I ever want to switch.