Pond Boss Forums INTRO Questions & Observations Geo Project

They have more stages than Boston's string of album releases

Yes, this one has a "flush all toilets @ time" function.

And in your location it needs every function you can think of and they better work right the first and every time least you turn to popsicles.

No worries, we live in the warm part of Minnesota.

HA! Warm part of MN. There is no such thing, except in July and August. hehehehe

Nice system! We've had ours for a year now and love it.

In addition to the Federal tax credit, we were able to get an energy efficiency credit from our electric coop for installing a geothermal unit. We had to fill out 2 pages of paperwork and now we have a big fat credit on our account. We won't be paying for electricity for several years.

Between the tax credits, electric company credits, and energy savings these things really do pay for themselves pretty quickly.

Ack, thanks. You are right about the payback. It happens quickly.

Now that our thermostat is programed correctly everything works according to initial design parameters. It still runs on the first stage mostly.

One question for you. Does the Geo keep the and area of the pond open all winter if you live somewhere that it gets down in the single digits at night?

Maybe I am not understanding how this works?

Thanks

The Geo system closed loop lies on the bottom of the pond in 10 feet of water so it has a negligible effect on water temperatures. I don't see how it could keep water open in an pond situation unless the pond was extremely small.

Dwight:

If it's a closed loop system, doesn't it take heat "out" of the pond in the winter, and put it back "in" during the summer?

Yes esshup you are correct it takes heat from the pond in the winter and put it in during the summer. Somewhere on the forum they crunched the numbers and it will have very little effect on the pond temp.

As noted above, pond loops really have very little affect on the pond. The additional loop and making sure there are lots of spacers in the loops has made all the difference in how our geo runs. It's is comfortable and even with single digit temperatures, it ran beautifully. We have a Honeywell thermostat that shows when your heat strips kick on--we changed ours out to one last year and highly recommend one. Thus far this year, the geo is running absolutely great.

Dwight, all your costs was right in line with ours and I'm figuring a 5 year payback. The only thing is once you get out of warranty, if you need service, the service for a specialized tech is on the high side of things compared to your older system. Oh, well....dot

The overnight low last night was -32F and at 11:00AM this morning it is still -20F. The Geo unit ran on the first and second stage most of the night. With a setting of 70F on the thermostat, the actual inside temperature never dropped below 69F. This means that the third electric resistance heating stage may never run. I can't imagine conditions in our locale that could cause the inside temperature to drop to 67.5F degrees (the resistance heating stage set point).

I have some understanding of how the system works. I am still amazed that a whole house can be heated in -32F temperatures by 40 degree pond water!

I'm amazed by this as well Dwight. When we eventually build our home on our property we are definitely going to install geothermal. For us it will be as much about the cooling in the summer as the heating in the winter.

Thank you, Dwight,


for helping me enjoy our balmy 9 deg F weather today.

How would you rate the home insulation (particularly ceiling/attic) and airtight-ness (new word)

I'm curious as we would like to build some day and planned on a geo unit. I was under the impression that a land based unit was more efficient. Did you compare costs and efficiency of pond vs. land based units? If so, how did they compare? Thanks!

I see where some of you figured a pay off for the geo thermal in 4 and 5 years and in my mind I try to figure out how it is figured? If in one case the cost totaled out at $17,500. If after the credits you had around $12,000 to spread out over 5 years this would figure out to saving over $2000 per year. I would assume by this the propane cost was extremely high. The convenience of the geo thermal would be extremly nice. I am trying to convert everything over to my Heat pump situation. I know that during cold weather I would be having electic heat as the heat pump could not convert the cold air to heat. Now if my total heating and cooling was about $1800 per year and this is about $150 per month. Could you with geo thermal give me some figures on how much I could realize in geo thermal savings---please.

We have a 7 month heating season, a 3 month air conditioning season and a month each spring transition and fall transition.

Our home is approximately 60 percent old construction 40 percent new construction. All the windows and doors are current double pane. The siding is relatively new on average and has taped one inch bead-board between the wall and siding.

In our area a pond based system is far superior to a ground system. There are several reasons for the difference. We have ground water flow in our pond that keeps the water temp around the loop constantly refreshed and very stable. Our pond is a pit type pond dug into the ground water rather than an impounded surface water type pond. Our soil below the frost line isn't soil at all, but gravel. When a Geo loop is in the water the transfer surface is 100% while in soil there small gaps and voids in the soil which affects the transfer of heat.



The savings are far greater in more extreme climates like Minnesota. See my comments to JHAP at the beginning of this post.

Try this calculator:
Geo Savings Calculator

Dwight:

I ran the calculator, and I may be reading the calculator incorrectly. Here's what it said:
System Comparisons:
1 Geothermal Heating and Cooling with Hot Water Generator
2 Natural Gas Furnace, 91% eff. / 10 SEER Air Conditioner / Natural Gas Water Heater
3 Natural Gas Furnace, 80% eff. / 10 SEER Air Conditioner / Natural Gas Water Heater

Annual heating, Cooling, and Hot Water Costs:
110 year old, 2300 sq. ft. home
South Bend, IN
System Heating Cooling Hot Water Totals Avg Monthly
1.......$1,606...$253.....$912....$2,771....$231
2.......$1,977...$643.....$607....$3,227....$269
3.......$2,213...$643.....$607....$3,463....$289

Electric rate: $0.143/kWh
Natural Gas Rate: $1.06/ccf

Does this mean that I'd only be saving an average of $38/month over the current system (system 2 in the data)?

If we get to low single digits, the third stage (heat strips) kick in for about an hour. The difference is with the new thermostat, we KNOW is it on...previously we never could tell without going downstairs.

That is amazing, that you haven't hit third stage; when we thought that, we ended up with quite an eletric bill when we first installed the geo (and after some fine-tuning the problem went away).

I'd be curious what others have experienced with when their heat strips do kick in.

We are definitely still pleased with the geo system inplace.

It is all about the extremity of your climate and the cost of energy in your area.

Natural gas is cheap compared to heating oil, LPG and electric on a heating unit per $ basis. If you were comparing Geo to oil or LPG heating your numbers would be quite different. Enjoy your natural gas while you can!

It probably has something to do with the sizing of your system. How many tons have you?

5 tons and five loops in the pond...they figured we'd used 105 hours of heat strips during the two coldest months due to heat loss from the house??? My husband thinks we maybe need a couple of more loops. May be to soon to tell, this is only our second year with geo. It's 18 degress right now and we're running straight off geo (no strips) and i know the strips come on like 1, 2, 3 or 4 at a time.

Ours is a 5 ton with 4 pond loops and 1 electric resistance heat "strip" that never runs, even at -32F

What brand and model is your Geo system? How well is your house insulated? I am curious about the large difference in what we are experiencing.