Geomthermal

[theoldwizard1]

I would not do geo again unless i had no other options or fuel cost was much higher.

You live in an area that has fairly "moderate" temperatures. Not too many extremely hot days and not too many extremely cold days. Geothermal pays back quickest in areas that have extreme cooling requirements (SE and SW). This is because most AC units are trying to move "heat" to an already "hot" environment (outside) and air is NOT a good conductor of heat.

With NG cost so low and probably staying, it just doesn't make a lot of sense.

I worked in the automotive compress natural gas (CNG) for a short time. I left for other reasons, but shortly afterwards the price of oil dropped and that killed the light duty CNG market. (For a few years prior, the price of natural gas dropped and it looked like CNG was going to be THE fuel of the future !) There still are a few places where you can get CNG for about $1 GGE but it still takes a lot of miles for the cost of the conversion to pay back.

 

[86turbodsl]

You live in an area that has fairly "moderate" temperatures. Not too many extremely hot days and not too many extremely cold days. Geothermal pays back quickest in areas that have extreme cooling requirements (SE and SW). This is because most AC units are trying to move "heat" to an already "hot" environment (outside) and air is NOT a good conductor of heat.

Geo for AC works pretty good even in this environment. You're trying to move heat from a high temp source to a low temp source, it WANTS to go there. COP is pretty good in the summer, as evidenced by my low-ish electric bills. The house is fairly big and the paint on it is dark. It's pretty comfortable and doesn't cost a ridiculous amount to cool. No tree cover at all.

 

[yeldogt]

Geo for AC works pretty good even in this environment. You're trying to move heat from a high temp source to a low temp source, it WANTS to go there. COP is pretty good in the summer, as evidenced by my low-ish electric bills. The house is fairly big and the paint on it is dark. It's pretty comfortable and doesn't cost a ridiculous amount to cool. No tree cover at all.

Around where my weekends house is in eastern PA --- it 's about the heat -- no NG and expensive power. Not many years ago it was straight oil or propane for winter heat. I'm talking large old stone homes or converted barns -- or both. Heat hogs. With all the advancements -- spray foam and windows mostly ... the heat loads have dropped dramatically. Add in the new HP's .. and current cheap fuel .. everything has changed. That's not to say that Geo is not the thing for the old places -- they still are needing lots of BTU's

 

[wdrumheller]

I have a 5 ton geothermal unit from Florida Heat Pumps and the local guy, Boyer's heating and air installed it. It's got three 350 ft deep wells and here's what I've found:

1. The pumps are rated for 50psi of the coolant/fluid and they break yearly at that psi. If you run them at 30psi, they work great and don't break.

2. I lose about 12oz of fluid every year and in the spring I need to recharge to maintain 30psi.

3. The relays for the coolant pumps got corroded on year 5 and I bought replacements and put them in myself and the system is good.

This thing pumps out HOT air in the winter and COLD air in the summer and needs some mechanical-engineer level maintenance otherwise I'd have called the HVAC guys about 10 times. Instead, I did some simple diagnosis and repair and did it myself. Electric bill went from $600 to $450/month. Then I installed a massive solar array and the electric bill went to $15/month. The combo pays off in about 8 years and I"m 3 years into the solar and I LOVE IT.

If you have the money and the good local engineering resources with trusted HVAC folks and solar install guys that you research and trust, then you can do amazing things.

I had to do 90% of the research myself and know what to ask for. You are your own advocate and you get what you insist on having.

Sorry to revive and old thread. I've had a drink of rum after adding fluid to my system tonight and searching the forum for other folks in my situation.

 

[theoldwizard1]

I lose about 12oz of fluid every year and in the spring I need to recharge to maintain 30psi.

Very odd !

Pressure (volume) of water (I assume it is just water or a fluid that won't harm the environment) really should be based on the temp of the fluid as it enters the well(s) and, more importantly the temp when it exits the well(s).

For heating, I would want the exit temp above 40-45F. For cooling, under 60-65F.

I had to do 90% of the research myself and know what to ask for. You are your own advocate and you get what you insist on having.

Best advice ! Too many people in the midwest have gone with horizontal loops and then have to rely on resistance heating during the coldest days of winter.

Sorry to revive and old thread. I've had a drink of rum after adding fluid to my system tonight ...

Have another one on me !

 

[6768rogues]

I think wells are better than horizontal loops. Are there any systems near you? Some ground works better than other ground. If there are none in your vicinity, you could have a test well installed. One I saw had a test well and they used equipment to test the capacity of the ground. They they could use the heat load of the building to calculate how many wells to install. If there is one in the vicinity, it might give some data. Without data, you are taking a shot in the dark about how many wells or how much loop to install.

 

[theoldwizard1]

I think wells are better than horizontal loops.

The benefit with wells is that if you under estimate you can drill another well. Not true with horizontal loops. I have heard of places where the loops were not buried deep enough and by mid winter the ground was frozen solid to below the depth of the loop.

 

[wdrumheller]

The benefit with wells is that if you under estimate you can drill another well. Not true with horizontal loops. I have heard of places where the loops were not buried deep enough and by mid winter the ground was frozen solid to below the depth of the loop.

My brother-in-law put in ground loops with a local builder that was not really familiar with the requirements. I looked at his ditch before they laid the loops and I told him "4 feet is not deep enough, make them dig 6 feet or more" and they did not. He was on emergency coil heat for two or three weeks this winter and bitched at me about how the geothermal system was not good enough. I asked "Did you do the Engineering work behind how they should be installed?" Of course not.

That's why I had a good team of Engineers doing my analysis before drilling, and used wells (among a few other reasons) and I'm so glad I did. They are wonderful and I would never do a ground loop if I did it again.

My uncle did a ground loop system and he's a Civil Engineer and he put his ground loops 40% deeper than recommended, and he's happy as a clam in a super big house with radiant heat through the floor, and forced air, all through the geothermal system. The plumbing system is a work of art.

He also put some sort of ridiculously efficient substrate below his house and his roof has some sort of 20" thick styrofoam super-green energy stuff so that it's mega-insulated. He brags that his electric bill is $50/month.

If my kids would leave the doors and windows closed all the time that would be a big help.

Time for more rum. Good grief.

 

[Jackfre]

So, Net, net, in a highly technical system from design to installation, controls, let alone service and you have to depend upon a series of companies, people, crafts, etc to have been engaged enough as well as knowledgeable enough to stay with their part while hoping the other guys are doing the same in order to realize the promised benefits and comfort. Hoping it is operating conomically, because it damned sure isn’t from a front end cost standpoint. When a design/installation problem occurs you will have all the parties in a circle and each will point to the guy next to him as the culprit. You will have those knowledgeable people retire, sell out, move or simply stop answering the phone once the one year labor warranty is up. I know geo works, but an average consumer is really exposed in these systems.

 

[yeldogt]

So, Net, net, in a highly technical system from design to installation, controls, let alone service and you have to depend upon a series of companies, people, crafts, etc to have been engaged enough as well as knowledgeable enough to stay with their part while hoping the other guys are doing the same in order to realize the promised benefits and comfort. Hoping it is operating conomically, because it damned sure isn’t from a front end cost standpoint. When a design/installation problem occurs you will have all the parties in a circle and each will point to the guy next to him as the culprit. You will have those knowledgeable people retire, sell out, move or simply stop answering the phone once the one year labor warranty is up. I know geo works, but an average consumer is really exposed in these systems.

Agree. The potential for mistakes around every corner .... Having investigated for each of my projects over the past 30 years the numbers just never work. Actually more viable years ago when there were few alternatives and energy costs climbing exponentially.

Spray foam was a huge factor -- foam and good windows changed the building load. When you reduce the overall energy load the potential saving drop ... cheaper energy and the doubling of AC/HP efficiencies really ended the debate.

Even large homes can be heated and cooled in many parts of the country for under 3k a year .... how much can be saved? Even cutting that in 1/2 ... is not going to make a 10 year payback possible.

 

[4 FN 27]

The benefit with wells is that if you under estimate you can drill another well. Not true with horizontal loops. I have heard of places where the loops were not buried deep enough and by mid winter the ground was frozen solid to below the depth of the loop.

Not so sure I would agree with this. No matter what you will have to dig down to the Manifold and add the loop whether it is a vertical or horizontal loop.

Now you can claim you heard of a place where the Loops were properly buried deep enough too.

That's why I had a good team of Engineers doing my analysis before drilling, and used wells (among a few other reasons) and I'm so glad I did. They are wonderful and I would never do a ground loop if I did it again.

I have Vertical Loops on the house Geo System and Horizontal Loops on the Shop (see post #18). Both design for the application, both effective. Behind the house we hit fractured bedrock at 140 feet. At the shop 446 feet away we hit fractured bedrock at 70 feet. We had to do Horizontal Bores. Fortunately my property has a high water table. Thus all my Horizontal Loops are in the Water Table which has the best thermal efficiency. The Verticals not so much. If I had it to do over again the House Loops would be Horizontal too.

So, Net, net, in a highly technical system from design to installation, controls, let alone service and you have to depend upon a series of companies, people, crafts, etc to have been engaged enough as well as knowledgeable enough to stay with their part while hoping the other guys are doing the same in order to realize the promised benefits and comfort. Hoping it is operating conomically, because it damned sure isn’t from a front end cost standpoint. When a design/installation problem occurs you will have all the parties in a circle and each will point to the guy next to him as the culprit. You will have those knowledgeable people retire, sell out, move or simply stop answering the phone once the one year labor warranty is up. I know geo works, but an average consumer is really exposed in these systems.

I picked the right designer/installer and it works effectively. We had a cold winter this year. Highest bill this winter to heat was $216 for 10574 sq ft (see post #18 for breakdown of temps and effective temps).

 

[Jackfre]

Quote: "I picked the right designer/installer and it works effectively. We had a cold winter this year. Highest bill this winter to heat was $216 for 10574 sq ft (see post #18 for breakdown of temps and effective temps)."

Congratulations! I am very happy for you. In my experience pulling off all of those segments of the job successfully is like winning the lottery.

 

[yeldogt]

4FN27: It's not a question of do they work when correctly installed .. it's a question of how much do they save?

Going from a single speed heat pump to VS system has more to do about the comfort they can provide vs what they save in electricity. Making hot water is all about doing it cheaply -- be it with a lot of human work using a wood boiler or using a refrigerant .. it's hot water. That's why when people get into what's better -- tank or instant on the forum to make DHW it's a little silly. It's all about costs to get what you want and need -- it's hot water.

From the sound of it your costs are a fraction of mine -- doing three proper wells in my area would have been at minimum 45k. Even with credits -- that's too big a number.to overcome.

Sounds like you have quite a system

 

[4 FN 27]

4FN27: It's not a question of do they work when correctly installed .. its a question of how much do they save?

Keep in mind we can only make an educated guess since we did this on new construction and do not have a base line on Natural Gas Heat to compare. Payback was estimated at 4.8 years and the monthly savings average was calculated based on 2008 standards equaled $458 average per month or $110K over 20 years.

4FN27:sound like you have quite a system

Both systems are. I would love to heat with wood but I would have to be there to fill the boiler. I have plenty of wood. Last winter we hauled 150 pick-up loads of split wood off the property and it didn't put a dent in the wood piles.

 

[LifeLongWNYer]

I went to a local geo installer when planning my ( as yet unbuilt ) garage. I think he was knowledgeable, he has been in the area doing geo systems for quite a while, but somehow, it just doesn't click for me to do a geo system.

First, there are a lot of variables he mentioned.... exactly what kind of soil I have, where the water table is and what I "might" expect from wells, and from deep wells. ( Generally drilling wells here is expensive, and a **** shoot. I have a buddy whose mother has a dug well, 3' in diameter and you can touch the water with a yard stick, his well is 200' feet away and 227' deep! )

Then he wanted to know how much electricity/fuel my garage will need. It isn't built yet, so I don't know. I understand the the insulation I install matters a lot, but he couldn't tell how much to install. He said "put in as much as you can afford, and we'll go from there." I thought it pretty vague.

Finally, he was less than informative about government and power company rebates. Add in my location my electricity comes from one company, and the ( electricity ) competitor of that company provides natural gas in this area. They don't get along, and rebates offered by one company change when they find out that you are in the other companies territory for one utility, and theirs for the other.

It sounds a little like buying a huge lottery ticket to me, I am just going to pass. I might be sorry later, but for now, I'll use that money for gas radiant heat and extras in the garage.




.

 

[yeldogt]

Keep in mind we can only make an educated guess since we did this on new construction and do not have a base line on Natural Gas Heat to compare. Payback was estimated at 4.8 years and the monthly savings average was calculated based on 2008 standards equaled $458 average per month or $110K over 20 years.



Both systems are. I would love to heat with wood but I would have to be there to fill the boiler. I have plenty of wood. Last winter we hauled 150 pick-up loads of split wood off the property and it didn't put a dent in the wood piles.

Around me -- The cost of the wells make the systems too expensive .. even when all the rebates were around. In my area the numbers make foam and better air to air equipment cost effective.

Honestly -- would have done it on my current project if I could have been within 10k at 15 years. My new build is in a very wealthy area -- people spend the 100k on geothermal wells to say they have it. My neighbor just spent 300k on pool project for a 12 week season .... and they have a shore house.

 

[Jackfre]

Around me -- The cost of the wells make the systems too expensive .. even when all the rebates were around. In my area the numbers make foam and better air to air equipment cost effective.

Honestly -- would have done it on my current project if I could have been within 10k at 15 years. My new build is in a very wealthy area -- people spend the 100k on geothermal wells to say they have it. My neighbor just spent 300k on pool project for a 12 week season .... and they have a shore house.

I have to think that the cost of wells and the rest of the system, vs the cost of a good conventional system just doesn’t make sense. Better to me to put the money into a good PV solar system.
Your comment on your neighbor is a hoot. I was on a job with a propane company way Down-East Maine years ago. The owner of the rather palatial estate directly on the coast had a very large tidal pool, which was heated, 24 hrs/day with propane. As the tide comes in every 12 hrs, the pool water was replaced at every high tide with water from Greenland and Atlantic Canada. I said to the manager of that branch, “You must love this guy?” He just smiled and rolled his eyes. You just cannot dream his stuff up.

 

[yeldogt]

I have to think that the cost of wells and the rest of the system, vs the cost of a good conventional system just doesn’t make sense. Better to me to put the money into a good PV solar system.
Your comment on your neighbor is a hoot. I was on a job with a propane company way Down-East Maine years ago. The owner of the rather palatial estate directly on the coast had a very large tidal pool, which was heated, 24 hrs/day with propane. As the tide comes in every 12 hrs, the pool water was replaced at every high tide with water from Greenland and Atlantic Canada. I said to the manager of that branch, “You must love this guy?” He just smiled and rolled his eyes. You just cannot dream his stuff up.

It's cost not workability. Current project is in an historic district w/ tight lot .. width not length. Not finding a nice place for the huge condensers found on current systems had me looking for alternatives. This property does not have NG. Geothermal obviously ... or maybe doing a remote air to water system. Nothing panned out and doing remote conventional heat pump condensers was not my preference -- knowing the problems that are encountered with long buried refrigerant lines. Geothermal is being squeezed by the new Heat Pumps -- at one time they could not work at any price ... now they work as well and do so at a very competitive price and efficiency. Modern air to air are matching what geothermal could do 15 years ago. Even if Geothermal can cut that in half again ... it's only 1/4 of the old number and rates are less vs 15 years ago. My other properties have NG -- nothing matches NG cost.

I have noticed changes in the Geo literature -- just as I have in the radiant. Both are premium products under pressure form competing systems in an overall depressed market -- I see the trade pushing the envelope to simplify the systems.

 

[4 FN 27]

In my experience pulling off all of those segments of the job successfully is like winning the lottery.

It sounds a little like buying a huge lottery ticket to me, I am just going to pass.

A good Geo System can be designed, built and installed at a given cost. One must then analyze is the equity injection worth the ROI. If I could do that with any given level of predictability I would play the Lottery and win applying the same investigative techniques deployed in my hunt for the right company to design, build and install my system(s).

In my tenure I have found in order to have a shot at winning the Lottery one must play. Maybe I should buy a ticket???

 

[theoldwizard1]

My daughter's father-in-law is a certified energy inspector. He built a new house a couple of years ago. Double 2x4 walls and God knows how much insulation.

"Average" size 1 story (< 2000 sq ft) and he heats and cools it with 1 small and 1 medium size mini-split. He just installed some solar panels to reduce his electric bill. Within the next 5 years he hopes to double or triple his solar and get an average bill of only the base meter fee !

 

[yeldogt]

My daughter's father-in-law is a certified energy inspector. He built a new house a couple of years ago. Double 2x4 walls and God knows how much insulation.

"Average" size 1 story (< 2000 sq ft) and he heats and cools it with 1 small and 1 medium size mini-split. He just installed some solar panels to reduce his electric bill. Within the next 5 years he hopes to double or triple his solar and get an average bill of only the base meter fee !

It's about finding the doable, practicable middle ground. What's good enough. I think energy standards for new buildings is a great idea .. and some states have great programs to encourage more efficient equipment and insulation standards above the base energy standards. We still build inefficient building ... but the answer is not "net zero" .... it's the same with solar. In the USA ...solar is all or nothing. In Africa I have partial solar hot wanter and heat .. they use a gas filled tube system that's very effective at absorbing the suns energy. It's not designed to do it all -- only to reduce when it can. Since we are only two people -- it does most of the hot water. The heat aspect better than expected. The key there is that it's so widespread -- simple standardized equipment ... affordable/ fixable.

 

[86turbodsl]

Highest bill this winter to heat was $216 for 10574 sq ft (see post #18 for breakdown of temps and effective temps).

WOW. What's your power cost, and what temps are you heating to?

I wish my GSHP was that cheap to run, and i'm only doing about 4500 ft2.

 

[4 FN 27]

WOW. What's your power cost, and what temps are you heating to?

I wish my GSHP was that cheap to run, and i'm only doing about 4500 ft2.

"(see post #18 for breakdown of temps and effective temps)."

Last I remember .086/KWH...so 50% of that on the Geo Side.

 

[86turbodsl]

"(see post #18 for breakdown of temps and effective temps)."

Last I remember .086/KWH...so 50% of that on the Geo Side.

Ok, that makes sense then. My electric co gets 0.119 / kwh and i get no break on geo. If i could get nat gas where i'm at, i would just go straight boiler and forget the geo honestly. This is my cheapest alternative.

 

[yeldogt]

"(see post #18 for breakdown of temps and effective temps)."

Last I remember .086/KWH...so 50% of that on the Geo Side.

Confused -- are you saying they charge you .043 KW for the geo operation? Separate meter? Any natural gas? (forget if I asked)


I'm at about 9k sf -- with a combined bill in the mid $500. But my electric is around .20KW.

 

[4 FN 27]

Confused -- are you saying they charge you .043 KW for the geo operation? Separate meter? Any natural gas? (forget if I asked)


I'm at about 9k sf -- with a combined bill in the mid $500. But my electric is around .20KW.

Yes .043...Wife just left or I would verify the exact amount. I know I am close.

Separate meter for the Geo.

On the house and Shop we have:

1 Natural Gas Meter each
1 Geothermal KWH Meter each
1 KWH Meter each

Both separate billing and the bill itself is itemized by Meter Number.

 

[woodzy]

Well, here is my thought on Geothermal. I live in lower Michigan by the Ohio border. I have plenty of land and thought of going with a Geothermal with ground loops. I paid the Builder the up-cost for this $13,000.
Just before groundbreaking, I talked to a co-worker and he has had Geothermal for the past 10 years. He gets a discount rate for geothermal meter (DTE) – I think around 4.5 cents per kWh. He said that his normal bill for electric was about $400 per month for heat / cool / hot water – all things Geothermal would take care of.
So, I calculated that to be about $4800 per year for all his utilities. He has a two story house about 2600 square feet, and I was building a ranch at 2300 square feet. My POCO (Consumer Energy) does not give discounts for Geothermal rate so our rate was like 10.5 cents per kWh. So in reality my bill would be closer to $9800 per year for the electric (If I built the exact home as he has).
So, my thought was this system would never pay for itself. Since I have natural gas at the street and the cost to get it to the house was $200 I went that route.
After one full year of electrical and gas bills after we moved in were $902.67 for electric and $732.46 for gas. That is a total of just over $1600 per year. There is no chance that Geothermal would save money. As the price of Natural gas and propane has dropped there is even better savings.

 

[NotOrganized]

We have a 3800 sq ft house that we insulated the crud out of. Went with two geo units one for each floor. Our lines are laid out in 5 600ft trenches about 5 ft deep. In the super hot Oklahoma summers where we have 30 plus days over 100, it seems to struggle a bit as the loop temps rise. It's been working for 15 years and no major issues. Did it pay for itself? I don't know. Electricity has been going up pretty steady, so i have to believe it is saving us money. It has no issue keeping us warm in winter, but we also have a propane fired floor loop that we finally brought online about 4 years ago.

In the end, I would do the Geo again without a thought. Much nicer not having a big noisy unit outside running all day in the summer. Our units are both on the second floor and pretty quiet.

 

[woodzy]

I think for cooling it has it benefits but if you use it to heat it does not compete with Natural Gas or maybe even propane at todays rate. Electric rates are too high to create heat that way. When the temperature drops below freezing - it is very hard to extract heat from the ground efficiently and using electric to heat is very expensive.

 

[yeldogt]

We have a 3800 sq ft house that we insulated the crud out of. Went with two geo units one for each floor. Our lines are laid out in 5 600ft trenches about 5 ft deep. In the super hot Oklahoma summers where we have 30 plus days over 100, it seems to struggle a bit as the loop temps rise. It's been working for 15 years and no major issues. Did it pay for itself? I don't know. Electricity has been going up pretty steady, so i have to believe it is saving us money. It has no issue keeping us warm in winter, but we also have a propane fired floor loop that we finally brought online about 4 years ago.

In the end, I would do the Geo again without a thought. Much nicer not having a big noisy unit outside running all day in the summer. Our units are both on the second floor and pretty quiet.

What's changing is the efficiency of the air to air -- the modern units are incredibly quiet. I have to look at the fan blades to be sure it's on.

 

[yeldogt]

Yes .043...Wife just left or I would verify the exact amount. I know I am close.

Separate meter for the Geo.

On the house and Shop we have:

1 Natural Gas Meter each
1 Geothermal KWH Meter each
1 KWH Meter each

Both separate billing and the bill itself is itemized by Meter Number.

At my power rates that would be $ 700 .... that's confusing. my other place is about 1/2 and I'm less with the air to air

 

[86turbodsl]

All this discussion reminded me that heating/cooling equipment best / lowest cost fit is often a moving target. I live in South central michigan, and have consumers energy like one other poster, and we USED to get a discount for geo rates, but not anymore. DTE still has it. Natural gas USED to be high (when we lived in Flint) but not anymore. Propane USED to be high, and fluctuates a lot based on how cold it gets.
Oil USED to be cheap, and now is sky high.

Wait 5 years, it'll probably change again. Electric is only going to go up because all the coal plants are getting shut down. Everyone is moving to natural gas fired plants. Guess what the natural gas cost is going to do???

 

[yeldogt]

All this discussion reminded me that heating/cooling equipment best / lowest cost fit is often a moving target. I live in South central michigan, and have consumers energy like one other poster, and we USED to get a discount for geo rates, but not anymore. DTE still has it. Natural gas USED to be high (when we lived in Flint) but not anymore. Propane USED to be high, and fluctuates a lot based on how cold it gets.
Oil USED to be cheap, and now is sky high.

Wait 5 years, it'll probably change again. Electric is only going to go up because all the coal plants are getting shut down. Everyone is moving to natural gas fired plants. Guess what the natural gas cost is going to do???

Overall energy costs are down.

I believe in subsidies/ rebates/ tax credits to motivate markets. But they have to end at some point and can't twist a market forever.

Partial solar is the answer today for the individual unless in a remote area -- the best bang for the buck ... highest payback for the subsidy. GEO is dropping .. not because it does not work .. but, because other items are replacing. (better insulation/ better air to air)

IMO -- should give more credits for low utility cost homes. Better building/ insulation is for 100 years ... better equipment forces innovation

 

[theoldwizard1]

After one full year of electrical and gas bills after we moved in were $902.67 for electric and $732.46 for gas. That is a total of just over $1600 per year. There is no chance that Geothermal would save money. As the price of Natural gas and propane has dropped there is even better savings.

It is hard to beat natural gas for heating. Propane is much more expensive.