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What Is Holding Back Geothermal Heating and Cooling?

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https://www.nationalgeographic.com/environment/great-energy-challenge/2013/10-myths-about-geothermal-heating-and-cooling/#close

Why are we not hearing more about geothermal heating and cooling, especially for very cold and hot areas? Mass use would reduce prices. It is especially efficient in areas with shallow groundwater. RCW

 

10 Myths About Geothermal Heating and Cooling

 

 

 

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1 hour ago, ronwagn said:

Why are we not hearing more about geothermal heating and cooling, especially for very cold and hot areas? Mass use would reduce prices. It is especially efficient in areas with shallow groundwater. RCW

Interesting - I had no real idea these systems existed - little talk about them in Australia - until I saw the link. Seems like a good idea but one deterrent may be the high up front investment required, despite the lower operating costs.. For what its worth there is this note in Wikipedia... "The initial cost can be two to five times that of a conventional heating system in most residential applications, new construction or existing." The same article says that its more cost effective for larger commercial buildings and harsher climates..  Still if governments insist on spending huge sums on renewables why not spend money on this stuff? One guess is that its not flashy or showy.. you can point to wind generators or PVs on roofs but not heat pump systems..  

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My boss has a ground source heat pump installed, he lives in the countryside where typically it would be an oil fired boiler system.

He wanted to "go green" so had one installed which cost him approx $38K , he then had a landscaping bill for $3K to put his garden back together.

He has had continued failures with this system (it might be the pump or heat exchanger aren't big enough) and he has said it has and continues to cost him a fortune.

I believe in many parts of Scandinavia this form of heating is installed as standard practice, so it must work.

This may be a 1 off where the contractor has done a particularly bad job but it does put me off.

Give me natural gas all day long!

https://www.geogreenpower.com/renewable-heat/ground-source-heat-pumps/?gclid=CjwKCAiA_f3uBRAmEiwAzPuaM2chhyvu78hm47rfs4UZGbhZY9HFg8njBQCnzGoTX_bwDHDI90ZzmBoC99UQAvD_BwE

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14 minutes ago, Rob Plant said:

My boss has a ground source heat pump installed, he lives in the countryside where typically it would be an oil fired boiler system.

He wanted to "go green" so had one installed which cost him approx $38K , he then had a landscaping bill for $3K to put his garden back together.

He has had continued failures with this system (it might be the pump or heat exchanger aren't big enough) and he has said it has and continues to cost him a fortune.

I believe in many parts of Scandinavia this form of heating is installed as standard practice, so it must work.

This may be a 1 off where the contractor has done a particularly bad job but it does put me off.

Give me natural gas all day long!

https://www.geogreenpower.com/renewable-heat/ground-source-heat-pumps/?gclid=CjwKCAiA_f3uBRAmEiwAzPuaM2chhyvu78hm47rfs4UZGbhZY9HFg8njBQCnzGoTX_bwDHDI90ZzmBoC99UQAvD_BwE

If NG available I would say go for that.

If you are in a locality where NG isn't available then GSHP are viable against the alternatives - oil / bottled gas / electric.

An ideal set up is where the house has underfloor heating. The problem with retrofitting is that radiators are not normally sized to adequately heat with a circulation temperature of 40-45 deg C. 

GSHP are best for rural location new builds where the insulation is maximised which offsets the size of the borehole / trench system needed for the ground loop to collect heat. 

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20 hours ago, NickW said:

An ideal set up is where the house has underfloor heating. The problem with retrofitting is that radiators are not normally sized to adequately heat with a circulation temperature of 40-45 deg C.

???  In Floor heating should never exceed ~30C at the highest.  Our home has this and so did my fathers and grandfathers home.  Can heat from any source be it propane, NG, electric, Solar, wood stove, geothermal.  I have heated with all of the above.  Current is Solar, Geothermal, Wood Stove, Propane, and Electric should the propane run out.  Yes, my basement looks like a rats nest of pipes and valves.  Wood stove has essentially been dumped, but if you want a LOT of heat QUICK, it is still the best option other than propane. 

The problem with heat pumps is that most do a chinsy cheap crap job as the people installing them know AC and do not know the HV part of HVAC which requires simple math as they do inadequate radiative cooling surface area because the VAST majority of installers just do off the shelf No brain engaged installs which in turns causes the air freezing condensate and piss poor COP and pump failure as it has to work extra hard, or horrifically inadequate surface area to the ground by not digging them deep enough, installing wells of adequate depth/quantity and then making sure you use the lowest coefficient of conduction for dry soil, and not wet.  The other idiot move is to have a pump run continuously and NOT install large heat water storage tanks.  Place tanks in basement and they heat the basement and the house all at the same time with zero heat lost. 

Great thing about radiative heating is that Joe Schmoe can do it himself with willing elbow grease and not pay some big wig dumbo to do it for him.  Just make sure your heat transfer RADIATORS are WAAAAYYY oversized.  This is especially problematic when temperature of soil and temperature of air are about the ~ same.

PS: I have never once changed the water glycol mix and neither has my father or grand father.  There is no maintenance other than a rare pump failure once every ~10 or 30 years or so and occasionally one can grow a little scale on the thermostatic valves which causes the temperature mixing to drift over time... Gosh, can you turn a valve and use a thermometer once a year for a power bill that is less than 1/3-->1/10 previous...

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(edited)

3 hours ago, footeab@yahoo.com said:

???  In Floor heating should never exceed ~30C at the highest.  Our home has this and so did my fathers and grandfathers home.  Can heat from any source be it propane, NG, electric, Solar, wood stove, geothermal.  I have heated with all of the above.  Current is Solar, Geothermal, Wood Stove, Propane, and Electric should the propane run out.  Yes, my basement looks like a rats nest of pipes and valves.  Wood stove has essentially been dumped, but if you want a LOT of heat QUICK, it is still the best option other than propane. 

The problem with heat pumps is that most do a chinsy cheap crap job as the people installing them know AC and do not know the HV part of HVAC which requires simple math as they do inadequate radiative cooling surface area because the VAST majority of installers just do off the shelf No brain engaged installs which in turns causes the air freezing condensate and piss poor COP and pump failure as it has to work extra hard, or horrifically inadequate surface area to the ground by not digging them deep enough, installing wells of adequate depth/quantity and then making sure you use the lowest coefficient of conduction for dry soil, and not wet.  The other idiot move is to have a pump run continuously and NOT install large heat water storage tanks.  Place tanks in basement and they heat the basement and the house all at the same time with zero heat lost. 

Great thing about radiative heating is that Joe Schmoe can do it himself with willing elbow grease and not pay some big wig dumbo to do it for him.  Just make sure your heat transfer RADIATORS are WAAAAYYY oversized.  This is especially problematic when temperature of soil and temperature of air are about the ~ same.

PS: I have never once changed the water glycol mix and neither has my father or grand father.  There is no maintenance other than a rare pump failure once every ~10 or 30 years or so and occasionally one can grow a little scale on the thermostatic valves which causes the temperature mixing to drift over time... Gosh, can you turn a valve and use a thermometer once a year for a power bill that is less than 1/3-->1/10 previous...

This suggests an upper limit of 55 Deg C but I would agree 30 Deg C is ideal for efficiency.

http://thegreenhome.co.uk/heating-renewables/underfloor-heating/what-are-the-temperature-limits-of-underfloor-heating/

Edited by NickW
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14 hours ago, NickW said:

This suggests an upper limit of 55 Deg C but I would agree 30 Deg C is ideal for efficiency.

http://thegreenhome.co.uk/heating-renewables/underfloor-heating/what-are-the-temperature-limits-of-underfloor-heating/

1) Radiant flooring is superior to all other forms of heating in nearly all cases if you asked me as it allows you to keep rooms at lower temperatures and you still feel warm.  Your feet remain warm and your head is NOT swealtering hot. 

2) Source of heat can be anything and

3) DID you BOTHER to read your link?  That is for emergency rating... Yes, you can run higher temps.  But, your flooring gets absolutely DESTROYED due to delta T between hot/cold in the floor itself. Buckles, delaminates, cracks.  Not to mention you can actually burn your feet if you stand on an area where the inlet of the floor loop is.  Absolutely NO ONE runs higher than 30C... unless solid concrete and then maybe 35C. 

Now if we are talking radiators, instead of radiator flooring, then yes upwards of 45C-->55C is ok.

55-->60C is usually what we keep our Hot water tanks at and then it is run through a mixing thermostatic valve for 30C.  Will drop as low as 45C under high use conditions.  Say you run dishwasher, laundry, take showers, and general heating all at the same time, but we put an inline propane heater and this never happens anymore either so.....  PS: During fall/spring when solar is bombing in and built up from summer, our hot water tank temps reach 80C and have had it at 95C once. 

4) Only downside?  Lower humidity in the home with radiant flooring, so those with sinus problems may or may not like it depending on your problem.  Bonus?  No mold spores. 

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(edited)

12 hours ago, footeab@yahoo.com said:

1) Radiant flooring is superior to all other forms of heating in nearly all cases if you asked me as it allows you to keep rooms at lower temperatures and you still feel warm.  Your feet remain warm and your head is NOT swealtering hot. 

2) Source of heat can be anything and

3) DID you BOTHER to read your link?  That is for emergency rating... Yes, you can run higher temps.  But, your flooring gets absolutely DESTROYED due to delta T between hot/cold in the floor itself. Buckles, delaminates, cracks.  Not to mention you can actually burn your feet if you stand on an area where the inlet of the floor loop is.  Absolutely NO ONE runs higher than 30C... unless solid concrete and then maybe 35C. 

Now if we are talking radiators, instead of radiator flooring, then yes upwards of 45C-->55C is ok.

55-->60C is usually what we keep our Hot water tanks at and then it is run through a mixing thermostatic valve for 30C.  Will drop as low as 45C under high use conditions.  Say you run dishwasher, laundry, take showers, and general heating all at the same time, but we put an inline propane heater and this never happens anymore either so.....  PS: During fall/spring when solar is bombing in and built up from summer, our hot water tank temps reach 80C and have had it at 95C once. 

4) Only downside?  Lower humidity in the home with radiant flooring, so those with sinus problems may or may not like it depending on your problem.  Bonus?  No mold spores. 

Yep - thats why I said upper limit. 

Most systems in the UK  are based on water circulating are in concrete hence the 40-45 degree point. 

Edited by NickW
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On 11/28/2019 at 3:48 AM, Rob Plant said:

My boss has a ground source heat pump installed, he lives in the countryside where typically it would be an oil fired boiler system.

He wanted to "go green" so had one installed which cost him approx $38K , he then had a landscaping bill for $3K to put his garden back together.

He has had continued failures with this system (it might be the pump or heat exchanger aren't big enough) and he has said it has and continues to cost him a fortune.

I believe in many parts of Scandinavia this form of heating is installed as standard practice, so it must work.

This may be a 1 off where the contractor has done a particularly bad job but it does put me off.

Give me natural gas all day long!

https://www.geogreenpower.com/renewable-heat/ground-source-heat-pumps/?gclid=CjwKCAiA_f3uBRAmEiwAzPuaM2chhyvu78hm47rfs4UZGbhZY9HFg8njBQCnzGoTX_bwDHDI90ZzmBoC99UQAvD_BwE

Yes, bad installation will kill a good thing any day. Insulation, window placement, and other things are a safer choice if no guarantees. I have an open natural gas flame going right now. 

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On 11/28/2019 at 4:06 AM, NickW said:

If NG available I would say go for that.

If you are in a locality where NG isn't available then GSHP are viable against the alternatives - oil / bottled gas / electric.

An ideal set up is where the house has underfloor heating. The problem with retrofitting is that radiators are not normally sized to adequately heat with a circulation temperature of 40-45 deg C. 

GSHP are best for rural location new builds where the insulation is maximised which offsets the size of the borehole / trench system needed for the ground loop to collect heat. 

Could a well driller dig the holes to the required depth for a self install? That would require the right components being easy to install also. I am not in need but still asking out of curiosity. Floor radiators on the wall were in my old uninsulated home. They worked great though. I had a natural gas boiler there. I would be afraid to attempt it myself. 

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On 11/27/2019 at 5:43 PM, markslawson said:

Interesting - I had no real idea these systems existed - little talk about them in Australia - until I saw the link. Seems like a good idea but one deterrent may be the high up front investment required, despite the lower operating costs.. For what its worth there is this note in Wikipedia... "The initial cost can be two to five times that of a conventional heating system in most residential applications, new construction or existing." The same article says that its more cost effective for larger commercial buildings and harsher climates..  Still if governments insist on spending huge sums on renewables why not spend money on this stuff? One guess is that its not flashy or showy.. you can point to wind generators or PVs on roofs but not heat pump systems..  

I think the most beneficial areas for geothermal heating and air conditioning would be cities with lots of coastline or on large rivers. or lakes. That means mabye half of our population if there could be enough pipes of the right size. This could be a really green thing, oh wait, we might discomfit a few fish around the pipes. What would Greta think?

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2 hours ago, ronwagn said:

Could a well driller dig the holes to the required depth for a self install? That would require the right components being easy to install also. I am not in need but still asking out of curiosity. Floor radiators on the wall were in my old uninsulated home. They worked great though. I had a natural gas boiler there. I would be afraid to attempt it myself. 

Yes.  Just dump a loop of pipe down hole and fill in with sand is how most do it.  The problem with wells is ground conduction.  If water is available(almost always is other than clay/hard rock): no problems.  .... Actually there is a massive problem as surface ground water is COLD whereas ground ground water is warm.  So, if you are in a VERY porous ground setting, geothermal wells, unless dug deep are not practical.

Fine Dry sand is at least 10X less conductive than wet sand(fill material for hole).  Why large geothermal setups use 2 wells.  Pump water down one well and draw the warm water up the other well after percolating through the ground(open loop).  For a single home... this is not done much.  Rule of thumb is that 1 600ft well = roughly 10ton HVAC unit(closed loop)

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3 minutes ago, footeab@yahoo.com said:

Pump water down one well and draw the warm water up the other well after percolating through the ground(open loop). 

Really? How much makeup water would you need? What about glycol? Seems… wrong 

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3 hours ago, Ward Smith said:

Really? How much makeup water would you need? What about glycol? Seems… wrong 

Glycol?  Say what?  Just water.  Moving water does not freeze and everything is buried below frost line anyways.  Water table is constant.  You aren't throwing the water away you know....

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10 hours ago, footeab@yahoo.com said:

Glycol?  Say what?  Just water.  Moving water does not freeze and everything is buried below frost line anyways.  Water table is constant.  You aren't throwing the water away you know....

Is the water still buried when it enters (and exits) your house? Where I live the aquifer is a constant 48 degrees F. Not much you can heat with 8.88C. I'm cool with closed loop systems, a bit leery of open loop, thinking about contaminants from the rock insinuating their way into the equipment. 

In a five spot oil well pattern, the produced water quickly reaches equilibrium with the injected water temperature. One flaw for heavy oils is the injected water is chilling the formation, raising the viscosity and lowering production. This is happening to Aramco for instance. 

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(edited)

19 hours ago, ronwagn said:

I think the most beneficial areas for geothermal heating and air conditioning would be cities with lots of coastline or on large rivers. or lakes. That means maybe half of our population if there could be enough pipes of the right size. This could be a really green thing, oh wait, we might discomfit a few fish around the pipes. What would Greta think?

Many of the large buildings in downtown Toronto share a water cooling system using great lake water.  It's runs on about 10% of the energy as traditional air conditioning.

Greta would approve.

https://www.acciona.ca/projects/construction/port-and-hydraulic-works/deep-lake-water-cooling-system/

Edited by Enthalpic
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(edited)

If you have in-floor heating put your bathrobe on the floor when you go to bed; when you get up it's nice and warm.

Edited by Enthalpic
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3 hours ago, Enthalpic said:

Underwater or in-ground computer servers make a lot of sense too; they make a ton of heat and run faster when cold.

https://www.theverge.com/2018/6/6/17433206/microsoft-underwater-data-center-project-natick

I think Google tried this on a pier and got chased off by local regulators. It was an hidden project of some kind. 

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6 hours ago, Ward Smith said:

Is the water still buried when it enters (and exits) your house? Where I live the aquifer is a constant 48 degrees F. Not much you can heat with 8.88C. I'm cool with closed loop systems, a bit leery of open loop, thinking about contaminants from the rock insinuating their way into the equipment. 

In a five spot oil well pattern, the produced water quickly reaches equilibrium with the injected water temperature. One flaw for heavy oils is the injected water is chilling the formation, raising the viscosity and lowering production. This is happening to Aramco for instance. 

Depends entirely on the outside air temperature.  Yes, open loop system can have scaling problems.  Especially the big operations.  Essentially you turn into a mining operation--> not good. 

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On 11/27/2019 at 10:57 PM, ronwagn said:

https://www.nationalgeographic.com/environment/great-energy-challenge/2013/10-myths-about-geothermal-heating-and-cooling/#close

Why are we not hearing more about geothermal heating and cooling, especially for very cold and hot areas? Mass use would reduce prices. It is especially efficient in areas with shallow groundwater. RCW

 

10 Myths About Geothermal Heating and Cooling

 

 

 

Just to report a project from Austria. We are evaluating the undeground of Vienna. It looks like the whole underground (about 3000 meters deep) is filled with hot springs. But it has been a project for many years.

It is positive to note that the distribution network to the houses in the city already largely exists. However, now it's burning with waste and gas. That can change tremendously by 2030 and around 2,200,000 people could then be supplied with geothermal energy.
 
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1 hour ago, Wolfgang Horn said:

Just to report a project from Austria. We are evaluating the undeground of Vienna. It looks like the whole underground (about 3000 meters deep) is filled with hot springs. But it has been a project for many years.

It is positive to note that the distribution network to the houses in the city already largely exists. However, now it's burning with waste and gas. That can change tremendously by 2030 and around 2,200,000 people could then be supplied with geothermal energy.
 

Maybe.  What you are missing is HEAT flow calculations.  Everywhere on earth is hot down deep. 

The question is NOT if the ground is hot.  The ground is hot.  How much heat FLOWS through where it is hot, to where it is cold.  This is the total POWER available for heating.  It is not as much as you would think. 

What most call geothermal is in fact geocooling till that heat is gone.  This is why Geothermal operations create earthquakes, because what they are actually doing is cooling down the earths crust.  Vast Majority of minerals shrink when cooled --> creates earthquakes.

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(edited)

On 2/26/2020 at 5:55 PM, footeab@yahoo.com said:

Maybe.  What you are missing is HEAT flow calculations.  Everywhere on earth is hot down deep. 

The question is NOT if the ground is hot.  The ground is hot.  How much heat FLOWS through where it is hot, to where it is cold.  This is the total POWER available for heating.  It is not as much as you would think. 

What most call geothermal is in fact geocooling till that heat is gone.  This is why Geothermal operations create earthquakes, because what they are actually doing is cooling down the earths crust.  Vast Majority of minerals shrink when cooled --> creates earthquakes.

so how does it work in Iceland? or do they just run the operations away from the populated areas?

There were attempts at geothermal fracking to get more steam, anything you know about that?

Edited by 0R0
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14 hours ago, 0R0 said:

so how does it work in Iceland? or do they just run the operations away from the populated areas?

There were attempts at geothermal fracking to get more steam, anything you know about that?

They sit on a volcano.... with gobs of heat conduction(new lava) to pull power from.  Differential in temperatures remember does not create power.  Rather rate of conduction/area*differential temps creates power.  Power is a rate.

Why Geothermal works in iceland and not in say, Hawaii, is that in Iceland the ground is supersaturated with water, so steam comes out, rather than H2S or other nasty stuff.  Why most geothermal "power stations" quickly turn into nightmares of mining operations where one pulls up all the nasty stuff as it is water soluable and not the good stuff.  Or in California's case, they pulled all the water out of the rock and now get no heat conduction and cannot produce enough power.  In Iceland my understanding is they have SO MUCH fresh water that most of the nasty stuff has already been dumped into the ocean.  Therefore what they are working with is steam instead some steam and gobs of calcium, magnesium, arsenic, barium, etc which precipitates out closing off the piping etc. 

As for iceland fracking: No I do not know, other than what anyone can read. 

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On 11/28/2019 at 5:57 AM, ronwagn said:

Why are we not hearing more about geothermal heating and cooling, especially for very cold and hot areas? Mass use would reduce prices. It is especially efficient in areas with shallow groundwater. RCW

Since the technology has been existing for more than 60 years like the solar system, the problems encountered might largely be the same...??

allow me to set a frame of reference using general aircon concept:

1. hot air in house drawn in, condensed while in contact with coolant, heat lost, water lost, liquid coolant vaporized gaining heat. Less humid cooler air produced, blown back into the room.

2. Vapor coolant pumped to compressor and condenser. Liquid coolant reappears and recycled. Heat lost and released into the air outside the house.

Here are a little summary highlights that intrigue my interest. I'm just a fan of science, not an engineer. Pardon me if the technical accuracy is not there.........

Quote

'Unlike ordinary heating and cooling systems, geothermal HVAC systems do not burn fossil fuel to generate heat; they simply transfer heat to and from the earth. Typically, electric power is used only to operate the unit’s fan, compressor, and pump.

reflective point: we are trying to transfer the heat built up at the center of earth to warm houses through geyser or hot spring? So.... correct me if I'm wrong.......... do we

a) wait for the geyser to explode in its frequency to bring us the energy we need? Then we conduct the outburst through pipes or extract the heat up and distribute it through pipes? and spread the heat with fan?

b) conduct hot water or heat from hot spring through pipes into  houses and spread the heat with fan?

c) extract underground warmer air during winter into houses through pipes and spread with fan?

d) extract cool water and cool air to reduce temperature in the house using pump and fan?

The unit’s fan, compressor, and pump are housed indoors, protected from the harsh weather conditions, so they tend to last for many years, often decades.

Fact: Geothermal HVAC systems use only one unit of electricity to move up to five units of cooling or heating from the earth to a building.

Fact: Geothermal HVAC systems remove four times more kilowatt-hours of consumption from the electrical grid per dollar spent than photovoltaic and wind power add to the electrical grid.'

what does this mean?

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