geothermal heat

[scsmith42]

This is all great info.

My electric bills are averaging about 5K per year (excludes barn), and propane adds another 2K or so.  I'd like to see what I can do to significantly reduce these bills, and HVAC is high on the list.

I have a backhoe and a lot of clay soil, so digging trenches is not a problem (or significant cost) for me.  I also have a pond; the closest portion is about 4' deep and about 400' from the house; the deepest portion is about 18' deep and 700' or so from the house.

I will probably stay away from the well concept, since that would not be cost-effective for me.

I've been wondering about what the most cost effective way to heat/cool the house, barn, and shops will be.  On the one hand, I can recirculate water from deep in the pond up to the house, and in addition to using it for geothermal, could also use it for a pre-cooling heat exchanger where I am using the cool pond water to cool the house air (thus reducing the amount of time that the AC needs to run).  However, I don't know if the cost to recirculate the water 24/7 will exceed the energy cost for the conventional AC.  Also don't know if the geothermal units are already so efficient that I won't gain much from this concept.

This may prove to be the best cocept for cooling the shop though, as I doubt that I'll want to spend the $ to operate an AC unit in there.  I'm thinking of an outdoor wood boiler for the shop heat.  Since the boiler will be about 500' away from the house, it may not be cost effective to try to recirculate the hot water from it to the house and back...

Also am wondering if it's more cost effective to take the geothermal loops to the deep portion of the pond, or to bring the cold pond water up to the geothermal unit.

Advice / input from y'all is welcome.  I really enjoyed the link that Stew posted.

Thanks.

Scott

[Wood_Niche]

My Geo Thermal unit is a Climatemaster.
Genesis Series GSW060 Water to water heat pump.
Pumping modules are Flow Controller 2.
I was going to post some pictures, but I can't quite do it yet. (computer illiterate...have to read more)
So, I posted pictures in my gallery.
The ground loop connects to the pump and them to the heat pump.
These's a bonus the two lines coming out on the lower right side go to the hot water tank.
So, when the pump is working there is excess hot water, which helps the hot water tank.

[metalspinner]

Thanks for the pics in your gallery.

You have done all the work to post the pic.  Now all you need to do is get the glory.
Just four more clicks and you have it done. 

Click on the pic you want to post from your gallery.  Then click the "Click to insert...." caption under the pic.  This copies it into your "edit" in the tool bar at the top of the screen.  Then go back to your post and click the curser where you want the pic to be.  Go to the "edit" in the tool bar and click "paste".  That's it.  You can double check the position when you preview your post.

[scsmith42]

Wood_niche - thanks for the info.  I'll add Climatemaster to my evaluation list.

Regards,

Scott

[slowzuki]

Some info for people planning:

Modern water-water heat pumps are hermaticly sealed at the factory like a fridge or window AC.  Older units were built on site and required recharging and had more frequent problems.

Loops are cheaper than wells, if you have the right type of ground.  This needs to be calculated based on heat pump size or the system will suck.  The best grounds are clays, wet soils, muddy ground, ponds, etc.   Sandy dry ground isn't great as it doesn't have as much heat capacity.

After the compressor, the water circulation pumps use the next most amount of power.  There are a number of ways to arrange the pumping so you don't use as much power.  For example, if you are using an open loop getting water from below your house, taking the discharge line to below the source will reduce your pumping requirments if you can keep the line primed.  A good designer can take care of these issues for you.  Closed loop is a bit easier to design, using large diameter piping and parallel coil setups.

[scsmith42]

Thanks Slozuki.  Fortunately I have very dense clay soil, and the pond is about 3 acres - so it should be a large enough heat sink for cooling.

Sounds like i need to identify a few quality vendors and have them evaluate my situation, and design accordingly.

Scott

[submarinesailor]

Scott,

Found this tech paper from DOE:  http://www1.eere.energy.gov/femp/pdfs/hyhgp_tir.pdf

Bruce

[submarinesailor]

Scott,

Here are several links we talked about Friday afternoon.  I have spoken with the inventor/orginal patient holder several times at several energy shows.  I liked the way he spoke, good old boy.

Bruce

Geothermal stainless steel plates for ponds
Spec Sheets for Slim Jims

[scsmith42]

Bruce, thanks for the great info. 

Scott

[Dave Shepard]

A friend of mine is going to heating a portion of his barn with geo. He has standard radiant tubing in the slab, and will circulate water from his well. I will ask him more details when I see him next. Another friend was working at a discontinued radar testing facility near me, which was privately owned at the time, when the USGS showed up to take samples of their well. The USGS has records of all drilled wells, and this one was listed at 1800'. The water temp. was almost 90° F. There was talk of developing geo. heat at that facility, but it changed hands before it ever happened. Too bad, it would have been a great thing.


Dave

[Polly]

   we have geo thermal water furnace three wells driller 75 ft deep in front yard the unit heats our hot water heats and air conditions our house we are total elec about 2600sq ft with the usual appliances  average elec bill pr month is around ninety dollars the unit is 12 yrs old and cost 7500 dollars at that time the electric co gave us 1000 dollars for having it installed making the total around 8500 dollars we are in north central ky i personally feel it is only way to go my brother in law built a new house last year using a heat pump and it was stolen before he could hook it up with geothermal everything is either in the house or under the ground good luck whatever you decide and happy sawing  

[olyman]

 we have geo thermal water furnace three wells driller 75 ft deep in front yard the unit heats our hot water heats and air conditions our house we are total elec about 2600sq ft with the usual appliances  average elec bill pr month is around ninety dollars the unit is 12 yrs old and cost 7500 dollars at that time the electric co gave us 1000 dollars for having it installed making the total around 8500 dollars we are in north central ky i personally feel it is only way to go my brother in law built a new house last year using a heat pump and it was stolen before he could hook it up with geothermal everything is either in the house or under the ground good luck whatever you decide and happy sawing       thieves------grrrrrrrrrrrrrr

[Part_Timer]

Hope I'm not to late on this one.

We installed a "hydroheat" geo unit 12 years ago and love it.  Ours is an open loop system that runs off of our drinking water well.  No extra well drilling required.  We have a large expansion tank and well pump (3/4) hourse that services the entire water system (house and heat).  In all the time we have had it we've replaced 2 blower motors and have the hvac guys come out every other year to check the compressor and give it a once over for good measure ( about $75) so all in all it has been a good investment.  The most important thing is to change the air filters when they get dirty.

Our electric bill is $130 each month on the budget.  We have no propne.  I do burn about $60-70 worth of Kero in the dead of winter when it drops below zero and we have the wood burner for backup, just in case.  before the woodburner our bill was $139 and we burnt maybe $200 worth of kero in the dead of winter.

Our house is a 1900 school house of about 1600sf but we had it spray foamed when we remodled.

we have no regrets about installing our system and would do it again no questions asked.

[scsmith42]

Thanks for the info - you're not too late!

Where I'm located, I spend about the same amount on heating as I do air conditioning; of the two the AC is where I really want to save $ (in case I ever add an outdoor boiler to help on the heating side).

[Lud]

Saw this on a search andthought I could add some insight as we've had Geothermal for about 6 years.

The equation is 1 for 5.  That is for 1 unit of electric you get 5 units of heat.  They laid four 500 fot rolls of 3/4" ABS five foot down in 4 foot wide trenchs.  A big Kubelko dug a 110' long trench  ( I thought he'd kee diggin' but the sidekick walked the trench and threw out a few rocks, dropped in a 500 foot roll and spread it out like a flat slinky ,  keeping the two ends together.  Then the Kubelko dug the second trench,  filling the first trench as he did!  Dug and buried the whole thing in a half day.  I was charged $500 for the install of the field which is called a 4 ton loop, 4 trenchs each with 500' of pipe equals 2000' foot linked by inch and a half going to the loop and back from the house.

So it was filled with methanol and water and quarter horse pumps push and pull.  Liquid is constant 55 degree and  the Geo unit acts like a heat pump ,  only it's no strain to pull 70 out of a constant 55 as opposed to trying to pull heat out of cold air.  The cooler fluid is pumped back thru the loop and comes back at 55 after going around the loop.

The summer months AC needs are likewise  excellent since pumps reverse and you pull cool out of the 55 and push warmer fluid out around the loop and the heat disipates over the length and the fluid comes back again at the 55.

A few coils were staked on top of a new gas furnace and the furnace blower blows it all thru the old ducting.  We do close different registers summer and winter to deal with pushing the Cool up and let it drool back down and conversely let the heat climb.

Expensive?  I've always said it was  a little over half the price of a Ford Focus and it's going to take care of us for the rest of our lives since we're staying at the farm.  We've been very happy with it's performance.