Geo thermal

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benjamin said:
Cal would tell me to keep my mouth shut, but on this site you get what you pay for. If you want somebody to tell you what you want to hear go listen to a politician.

Geothermal with a lake loop sounds great to me. My first thought was that it's hard to justify geo on dollars and cents when you compare it to mild passive solar with slightly improved insulation, but then you go and mention full log construction, so forget about low heat loss. Second thought was that trenches or wells might provide a higher source temp as the lake will get cold fast, not from your heat pump, just from winter. If the lake is 40 and the well water is 55 it might not be that big of a difference, especially since you can throw a lot more pipe in the lake easier than you can add more trench and you're probably going to be looking at a bigger system.

It's awfully nice to have air conditioning here in southern WI, even if we only use it a week a year, but then the radiant slabs would be nice also, I can't help on that one. Another nice feature is a water heating system, either desuperheater, or with a water to water unit that switches between heat and hot water. Again, I can't help with the cost or payback on this, just something to consider.

I've worked with FHP and Tetco, and haven't seen any problems with either in my limited experience.

I have geothermal. Why would I tell you to keep your mouth shut unless I actually thought you would?
Do you have geothermal? Do you install geothermal?
 
I have a FHP jerry rigged on an open pump and dump system that is used for a little bit of air conditioning and a little heat. I've installed a few others and serviced a few others.

I don't claim to be an authority. And I apologize for turning the green room into the ash can. For some reason "green" stirs up strong opinions. Maybe because there's a lot of smoke and mirrors and not enough reality?
 
You are fine in my book. Wish I knew how to install those systems.
 
I do like your thoughts keep them coming. There will not be alot of heat loss in our log home. It will be a full log home-hybrid. We will be doing the basement above the grade height so we can walk directly into the home without steps, the first log about 20" dia will start about 32 inches high we will go to 9ft for the first floor but everything after that will be conventional construction including 2x8 loft walls conventional truss and sprayed foam insulation. We are going for a tight wrap and high r-values. Whis is FHP and Tetco are these contractors?


Dave



benjamin said:
Cal would tell me to keep my mouth shut, but on this site you get what you pay for. If you want somebody to tell you what you want to hear go listen to a politician.

Geothermal with a lake loop sounds great to me. My first thought was that it's hard to justify geo on dollars and cents when you compare it to mild passive solar with slightly improved insulation, but then you go and mention full log construction, so forget about low heat loss. Second thought was that trenches or wells might provide a higher source temp as the lake will get cold fast, not from your heat pump, just from winter. If the lake is 40 and the well water is 55 it might not be that big of a difference, especially since you can throw a lot more pipe in the lake easier than you can add more trench and you're probably going to be looking at a bigger system.

It's awfully nice to have air conditioning here in southern WI, even if we only use it a week a year, but then the radiant slabs would be nice also, I can't help on that one. Another nice feature is a water heating system, either desuperheater, or with a water to water unit that switches between heat and hot water. Again, I can't help with the cost or payback on this, just something to consider.

I've worked with FHP and Tetco, and haven't seen any problems with either in my limited experience.
 
I'm curious about the lake temp during the Winter. I was at a farm about a month ago and the home was heated/cooled by geothermal. I asked where his ground loop was and he pointed to a 50' diameter pond that I thought was for his beef herd, but he told me that's where his loops are. I didn't get into depth/construction but was surprised how tiny it was. Some things I've learned/heard while researching for my own house.

Electric is not as cheap as you'd think (maybe for your, but not for us @ .14KW/h. If your'e going to air-condition in the Summer, then great because you've effectively cut your payback period in 1/2. If not then 10 years is now 20 years, and if you don't need it (I don't need it for the 10 days a year) don' justify it.
Pump and Dump setups can ruin your water supply, and mess up your drinking well.
If your loops are not sized correctly you can freeze the ground/well.
If your loops are too long/too much resistance you will need a bigger pump, and will be wasting electricity.
Water temperature: There is a limit to what you can get. This differential is the biggest problem with geothermal, and in essence you will plan your whole house around it. 130F is about the max you're going to get, but that doesn't tell the whole story, because its more of a differential than a max temp. If you've got a 50F ground loop and its 30 degrees outside you'll heat your house fine, but as it gets colder you will be pulling more heat from the ground, in effect cooling your ground loop. Soon you'll find that its -10 degrees outside and your ground loop is now 20F. You're heat pump has a max differential, and can't heat higher than that. If your loop temp goes below your design temp you're screwed, or its time for supplemental heat.

You've got 2 things that I don't. A pond and new construction. If I were building new I would definately do geothermal.
 
benjamin said:
Cal would tell me to keep my mouth shut, but on this site you get what you pay for. If you want somebody to tell you what you want to hear go listen to a politician.

...

It's awfully nice to have air conditioning here in southern WI, even if we only use it a week a year, but then the radiant slabs would be nice also, I can't help on that one. Another nice feature is a water heating system, either desuperheater, or with a water to water unit that switches between heat and hot water. Again, I can't help with the cost or payback on this, just something to consider.

I've worked with FHP and Tetco, and haven't seen any problems with either in my limited experience.

Good point on the domestic water heating in the summer using the desuperheater. I wish my GHP system was equipped with one.
 
FHP is Florida Heat Pump except they dropped the Florida reference for credibility in the north. Basically any high efficiency unit will have similar components made by the same third parties, the heat exchangers, expansion valves, controls and copeland scroll compressors are just assembled by whichever manufacturer.

This is the exact unit and seller that I got several from. Not a bad deal considering it includes the desuperheater, little bronze taco pump for hot water, and a big grundfos for the ground loop.
http://cgi.ebay.com/FHP-MANUFACTURI...022460?pt=Air_Conditioner&hash=item1c178a473c

Just in case any DYIers are interested. Unlike split systems, all of the refrigerant is contained inside of the unit, there are only water lines to hook up, and 20 amp 220 electricity. The hardest part is hooking up the thermostat.

The OP seems the perfect candidate for pump and dump water to water heated slabs. The system should be set up to make hot water directly, not with a desuperheater that only makes hot water on the two air conditioning days. With good insulation, slab heat and well water supply you might end up pumping from 50 to 80 degrees, just about as low as you're going to get.

Tetco makes a direct water cooled coil for air conditioning. They don't work the greatest, but for the few days that it's needed anybody could rig something similar up from an old A-coil, ten feet of duct and a small blower.
 
Since Geo-thermal is so expensive to install i would think a case may be made for an elaborate solar system ,of which the Fuel is FREE. With ELectric rates rising, you can get both heat and electricity from a solar system. Another factor is additional insulation which can have a big payback per dollar spent. Personally after addressing insulation levels it hard to beat solar and wood for cost of fuel and heat, if you are able. If you can not deal with the labor involved with wood then you can make a better case for Geo.IMO
 
I know a guy that looked into solar. He would be totaly off grid. No electric bills at all. The total cost for it $100,000. He can get 30% back form the government but it would still cost $70,000.
 
CALJREICH said:
I know a guy that looked into solar. He would be totaly off grid. No electric bills at all. The total cost for it $100,000. He can get 30% back form the government but it would still cost $70,000.

He must live in the White house. Most likely the lions share of this system was for electricity and not heat.I think getting your Heat from solar is far more efficient than trying to get your electric power, cost wise. I get easily 60 % of my heat on a sunny winter day, for a $600 investment which includes 6 large (overstock auction) windows i used to close in a 24' porch on the south side of my house. My central heat does not run from about 9am till midnight as long as its a sunny day no matter the outside temp.So after midnight till 9AM the next day is when i need to burn fuel for the other 40%. I could improve this performance simply by finishing insulating this 100 year old house. Although this is on the very low end of the average solar investment it does show whats possible. The very first winter i saved about $800-1000 worth of oil. Nice payback.
 
trump said:
CALJREICH said:
I know a guy that looked into solar. He would be totaly off grid. No electric bills at all. The total cost for it $100,000. He can get 30% back form the government but it would still cost $70,000.

He must live in the White house. Most likely the lions share of this system was for electricity and not heat.I think getting your Heat from solar is far more efficient than trying to get your electric power, cost wise. I get easily 60 % of my heat on a sunny winter day, for a $600 investment which includes 6 large (overstock auction) windows i used to close in a 24' porch on the south side of my house. My central heat does not run from about 9am till midnight as long as its a sunny day no matter the outside temp.So after midnight till 9AM the next day is when i need to burn fuel for the other 40%. I could improve this performance simply by finishing insulating this 100 year old house. Although this is on the very low end of the average solar investment it does show whats possible. The very first winter i saved about $800-1000 worth of oil. Nice payback.

Passive solar heating is definitely the low hanging fruit. For certain installations solar electric can be competitive with utility electric, depending upon the distance from the road to the house. In other cases very high electric rates/usage may make a solar electric installation not only feasible but profitable. When one throws an electric vehicle in the mix, the payback/self sufficiency could be a great investment. Additionaly, every time the rates go up in the future, the payback date gets sooner. Considering the long life span of photo-voltaic panels, I would love to be installing a big system. When I am busy in the blacksmith shop, $400 a month is not unusual. Even without running welding machines, airc ompressors, etc, my electric bill is arround $300/month.
 
My electric Bill is about $80 a month For a 3000SF home, 2 fridges and a freezer going, 4 computers 55"Lcd tv,seems cheap to me even though its about 13C a Kwh. So its not a big concern right now, but would love to have an electric pickup truck.
 
trump said:
CALJREICH said:
I know a guy that looked into solar. He would be totaly off grid. No electric bills at all. The total cost for it $100,000. He can get 30% back form the government but it would still cost $70,000.

He must live in the White house. Most likely the lions share of this system was for electricity and not heat.I think getting your Heat from solar is far more efficient than trying to get your electric power, cost wise. I get easily 60 % of my heat on a sunny winter day, for a $600 investment which includes 6 large (overstock auction) windows i used to close in a 24' porch on the south side of my house. My central heat does not run from about 9am till midnight as long as its a sunny day no matter the outside temp.So after midnight till 9AM the next day is when i need to burn fuel for the other 40%. I could improve this performance simply by finishing insulating this 100 year old house. Although this is on the very low end of the average solar investment it does show whats possible. The very first winter i saved about $800-1000 worth of oil. Nice payback.

I was just stating an estimate a guy I know got for solar system that would provide all heating and electric for his home.I thought it was crazy expensive too, but I don't know why anyone would think to compare that system with 6 big windows installed on an enclosed porch facing south.
Might as well compare a lit match with the sun.
 
CALJREICH said:
trump said:
CALJREICH said:
I know a guy that looked into solar. He would be totaly off grid. No electric bills at all. The total cost for it $100,000. He can get 30% back form the government but it would still cost $70,000.

He must live in the White house. Most likely the lions share of this system was for electricity and not heat.I think getting your Heat from solar is far more efficient than trying to get your electric power, cost wise. I get easily 60 % of my heat on a sunny winter day, for a $600 investment which includes 6 large (overstock auction) windows i used to close in a 24' porch on the south side of my house. My central heat does not run from about 9am till midnight as long as its a sunny day no matter the outside temp.So after midnight till 9AM the next day is when i need to burn fuel for the other 40%. I could improve this performance simply by finishing insulating this 100 year old house. Although this is on the very low end of the average solar investment it does show whats possible. The very first winter i saved about $800-1000 worth of oil. Nice payback.

I was just stating an estimate a guy I know got for solar system that would provide all heating and electric for his home.I thought it was crazy expensive too, but I don't know why anyone would think to compare that system with 6 big windows installed on an enclosed porch facing south.
Might as well compare a lit match with the sun.

To put it in simple terms, you dont need to spend $100,000 to get a substantial part of your heating needs from solar.
 
trump said:
...

...I think getting your Heat from solar is far more efficient than trying to get your electric power, cost wise. I get easily 60 % of my heat on a sunny winter day, for a $600 investment which includes 6 large (overstock auction) windows i used to close in a 24' porch on the south side of my house. My central heat does not run from about 9am till midnight as long as its a sunny day no matter the outside temp.So after midnight till 9AM the next day is when i need to burn fuel for the other 40%. I could improve this performance simply by finishing insulating this 100 year old house. Although this is on the very low end of the average solar investment it does show whats possible. The very first winter i saved about $800-1000 worth of oil. Nice payback.

We're off the original topic now but I think you make a good point and one pertinent to this discussion...

Many people make the mistake of assuming that capturing solar energy requires complicated and expensive equipment. Also, the most cost-effective way to make use of solar energy is to make use of it as delivered; as light and heat.

Though it has its place, conversion of sunlight to electricity increases cost and complexity.

I'm convinced, though not certain, that most of the electricity that we buy at our house goes to producing heat, whether for domestic hot water or HVAC (geothermal). I look forward to the day when we can harness the sun to accomplish both these tasks at our house.
 
Semipro said:
trump said:
...

...I think getting your Heat from solar is far more efficient than trying to get your electric power, cost wise. I get easily 60 % of my heat on a sunny winter day, for a $600 investment which includes 6 large (overstock auction) windows i used to close in a 24' porch on the south side of my house. My central heat does not run from about 9am till midnight as long as its a sunny day no matter the outside temp.So after midnight till 9AM the next day is when i need to burn fuel for the other 40%. I could improve this performance simply by finishing insulating this 100 year old house. Although this is on the very low end of the average solar investment it does show whats possible. The very first winter i saved about $800-1000 worth of oil. Nice payback.

We're off the original topic now but I think you make a good point and one pertinent to this discussion...

Many people make the mistake of assuming that capturing solar energy requires complicated and expensive equipment. Also, the most cost-effective way to make use of solar energy is to make use of it as delivered; as light and heat.

Though it has its place, conversion of sunlight to electricity increases cost and complexity.

I'm convinced, though not certain, that most of the electricity that we buy at our house goes to producing heat, whether for domestic hot water or HVAC (geothermal). I look forward to the day when we can harness the sun to accomplish both these tasks at our house.

Put me down as CERTAIN that most of the electricity we buy is used to produce heat.(that is if you have electric heat whether its a heat pump or electric resistance heating)The 2 largest would be Home heat,water heat. Both of which can and are harnessing the sun in an ever growing # of homes. Im also convinced that in some homes money spent on solar solutions and insulation is more cost effective dollar for dollar than geo-thermal.
 
trump said:
CALJREICH said:
trump said:
CALJREICH said:
I know a guy that looked into solar. He would be totaly off grid. No electric bills at all. The total cost for it $100,000. He can get 30% back form the government but it would still cost $70,000.

He must live in the White house. Most likely the lions share of this system was for electricity and not heat.I think getting your Heat from solar is far more efficient than trying to get your electric power, cost wise. I get easily 60 % of my heat on a sunny winter day, for a $600 investment which includes 6 large (overstock auction) windows i used to close in a 24' porch on the south side of my house. My central heat does not run from about 9am till midnight as long as its a sunny day no matter the outside temp.So after midnight till 9AM the next day is when i need to burn fuel for the other 40%. I could improve this performance simply by finishing insulating this 100 year old house. Although this is on the very low end of the average solar investment it does show whats possible. The very first winter i saved about $800-1000 worth of oil. Nice payback.

I was just stating an estimate a guy I know got for solar system that would provide all heating and electric for his home.I thought it was crazy expensive too, but I don't know why anyone would think to compare that system with 6 big windows installed on an enclosed porch facing south.
Might as well compare a lit match with the sun.

To put it in simple terms, you dont need to spend $100,000 to get a substantial part of your heating needs from solar.

I never said you need to spend anything. I was just stating an estimate an acquatance got for solar that would provide all his electric and heat , OK. Now here I go putting it in simple terms , I don't care if you live in a tent and heat with freshly slaughtered animals , I was just conveying a price a guy got from an outfit that installs solar system.
 
Getting back on track a little. I had a first sit down with my local Waterfurnace dealer last Friday. I was not impressed and he has not installed a Geo system yet. My Brother who works for a large mechanical firm out of Milwaukee, he's been asking his peers about Geo. His last request to me this morning was DON'T DO IT. ALL of the feed back he gets is GEO works much better as a cooling unit than a heating unit. He was told by one of his good friends that no matter how good the unit was installed and no matter what type of field it had that when the tempature drops below 25 degrees the Geo would need some type of assist to get it at a comfortable tempature in the house for[2300sqft] comfort. So my question, does anyone HERE or does anyone know anyone with a GEO system that does not meet some type of the statement above. Does anyone know of a person that has a unit installed that heats at all times without assist? I have people that are leaders in the industry wispering "stay away" Is Geo just another item that does not deliver???? ALL of the post so far leads me to beleive there are issues. Please anyone in cold climates Mane, North Minnesota, Wisconsin and Michigan.

Dave

Hansson said:
Geo thermal is very big over here.Everyone is getting it.
It`s like a big hype!

My neighbor has drilled two holes 200meter deep for the heatpump.

70% of all new building have a heatpump.

Pellets an wood heat is going down.
 
Cal
I never said you need to spend anything. I was just stating an estimate an acquatance got for solar that would provide all his electric and heat , OK. Now here I go putting it in simple terms , I don’t care if you live in a tent and heat with freshly slaughtered animals , I was just conveying a price a guy got from an outfit that installs solar system.

====================
You gave an example of the extreme high cost solar system and i gave an example at the low end, so i dont see the problem. Same with Geo-Thermal If you do all the work yourself and just buy the hardware you can put together a system for a small fraction of most estimates. Same with wood stoves ,i hear estimates for installation thats 3-4 times the price of the stove.
 
Midalake said:
Getting back on track a little. I had a first sit down with my local Waterfurnace dealer last Friday. I was not impressed and he has not installed a Geo system yet. My Brother who works for a large mechanical firm out of Milwaukee, he's been asking his peers about Geo. His last request to me this morning was DON'T DO IT. ALL of the feed back he gets is GEO works much better as a cooling unit than a heating unit. He was told by one of his good friends that no matter how good the unit was installed and no matter what type of field it had that when the tempature drops below 25 degrees the Geo would need some type of assist to get it at a comfortable tempature in the house for[2300sqft] comfort. So my question, does anyone HERE or does anyone know anyone with a GEO system that does not meet some type of the statement above. Does anyone know of a person that has a unit installed that heats at all times without assist? I have people that are leaders in the industry wispering "stay away" Is Geo just another item that does not deliver???? ALL of the post so far leads me to beleive there are issues. Please anyone in cold climates Mane, North Minnesota, Wisconsin and Michigan.

Dave

Hansson said:
Geo thermal is very big over here.Everyone is getting it.
It`s like a big hype!

My neighbor has drilled two holes 200meter deep for the heatpump.

70% of all new building have a heatpump.

Pellets an wood heat is going down.

I was under the impression that if the system is properly sized you would never need any kind of backup heat. Cal J Reich stated in an earlier post that his system does not need backup.
One of my best friends has Geo and i dont think he has any type of backup. So far he likes the system although hes not sure if he will recoup the cost,but hes gettin kinda old and one of the best things about Geo is set it and forget it.
 
Your brother's friend is either wrong, or assuming this is existing drafty construction, or confusing this with air source heat pumps. The strength of geo is the stable source temperature, well water won't fluctuate more than a few degrees. Even the lake bottom won't get colder than whatever the thermocline temperature is, 39? If your heat loss is less than the capacity of the heat pump it will keep up.

I have installed two open (well water) systems in Central Wisconsin that have heated flawlessly (except for thermostat failure) for the last few winters, last winter's low temp was -30. These two houses are a similar size to yours. One is a new modular with 2"of foam outside and under the basement walls, the other is an old farmhouse with new windows, 2" of foam outside of basement walls and a lot of cellulose. No passive solar or wood burner in either one.

These are both heated with the unit I linked above, a 2.5 ton/30,000 btu unit. With a used unit and the family labor rate, the payoff on these was a few months compared to propane and oil. Cheap AC and hot water included.

I couldn't recomend this small of a unit because I don't have any idea what your heat loss will be, I'm a skeptic of log homes but we can fight that out some other time. I would find someone who has done a water to water system w/ hot water who can tell you how to go about it. I know a friend of a friend who has this system (6ton/72,000btu) on a ground loop that works great for him, he even gets a "dual fuel" electric rate. Look up the cost calculators for electric vs propane they're pretty close to even right now (in the midwest). Figure the COP and you'll be paying a third of the cost of propane.
 
benjamin said:
Your brother's friend is either wrong, or assuming this is existing drafty construction, or confusing this with air source heat pumps. The strength of geo is the stable source temperature, well water won't fluctuate more than a few degrees. Even the lake bottom won't get colder than whatever the thermocline temperature is, 39? If your heat loss is less than the capacity of the heat pump it will keep up.

I have installed two open (well water) systems in Central Wisconsin that have heated flawlessly (except for thermostat failure) for the last few winters, last winter's low temp was -30. These two houses are a similar size to yours. One is a new modular with 2"of foam outside and under the basement walls, the other is an old farmhouse with new windows, 2" of foam outside of basement walls and a lot of cellulose. No passive solar or wood burner in either one.

These are both heated with the unit I linked above, a 2.5 ton/30,000 btu unit. With a used unit and the family labor rate, the payoff on these was a few months compared to propane and oil. Cheap AC and hot water included.

I don't have any idea what your heat loss will be, I'm a skeptic of log homes but we can fight that out some other time. I would find someone who has done a water to water system w/ hot water who can tell you how to go about it. I know a friend of a friend who has this system on a ground loop that works great for him, he even gets a "dual fuel" electric rate. Look up the cost calculators for electric vs propane they're pretty close to even right now (in the midwest). Figure the COP and you'll be paying a third of the cost of propane.
I these house are so well insulated that they only need 30000 BTUs to heat, the size of an average hot water heater, then i would imagine you could heat them at lo cost no matter what your heating fuel source may be.NOT?
 
These units are WAY undersized so they run almost continuously for many weeks. Not cheap heat in my book, but about 1/3 the cost of propane or fuel oil. Winter electricity rate is under 10cents a KWH here, makes a difference.
 
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