Geothermal heating for House

[woodzy]

I’m going to toss this up for discussion because I’m not sure how long payback would be on a geothermal system. And I want other to understand what costs are involved with geothermal.

Here is some history.
I just had a new house built and I have plenty of room for coils in my lot (3 acres). When I asked the contractor to quote a Geothermal option, it was an addition $13,000 over the natural gas furnace.

Some details:
House is 2230 square foot ranch, very well insulated, full basement (not finished) and 2x4 walls. Installed in the house was a 60,000 96% Natural Gas Furnace. When we had temperatures below 0°F, the furnace had not issues keeping the house at 72° and I would say the furnace didn’t really need to run ½ the time.

A co-worker of mine built about the same size house as this a few years ago and he installed Geothermal but his Electric Company give him a discounted rate for his energy consumption for this system. His charge for Kilowatt is about .07 cents per kilowatt hour once you figure in all taxes..

Now the facts and figures:
My natural gas for the past 30 days amounted to $113.00. This includes furnace, hot water heat, and range/oven, dryer.
My co-worker bill for only the geothermal system was $310 which in my utility rates would be closer to $630 since they won’t discount for geothermal.

Now, I realize that if you don’t have access to natural gas and only propane, maybe Geothermal is the way to go but I don’t see a payback using it for heating. I also understand that A/C is almost free (except of the power to run the pumps) but until I have an official summer electrical bill, I cannot confirm how much the electrical for just the A/C would be. Maybe they should have a hybrid system with a natural gas for heating and Geothermal for cooling.

Opinion
I think this Geothermal idea is plausible if you are in an area where you only have electric, and you want to feel good about not using the planets resources (even though they are used in the generation of electricity). The additional cost of the geothermal system in my situation would never pay for itself, and I’m pretty sure it would cost me a lot more in the long haul. Just the additional $13,000 would make this upside down without even comparing electricity to run this system.

 

[yeldogt]

I'm doing the calculations on this currently. With natural gas available I can't see how the numbers work based on current NG heating costs

I don't have NG available ... and .. I can't do the coils. In my area we have to drill wells. Without the tax credit the payback is into another lifetime. I'm in the mid atlantic so it is normal summertime A/C use


The key is building an energy efficient house --- keeping the equipment as small as possible and minimizing the number of wells. I still can't get the Geothermal #'s to work .. as I need three wells.

Air to Air heat pumps are getting better and better so the cost benefit of the Geo is getting closer

 

[ratdoggy]

I looked into geothermal when my house was built.
Too much money
More complicated
ROI was never going to happen before the unit crapped the bed.
We have natural gas so it didn't pay
2500 sq ft home.With 3 kids.....heat,drier,hot water, fireplace and cooking are all gas.
My bill is $65 per month.

 

[kd3pc]

One needs to understand that at one time or another, every fuel has been "cheaply" or "outrageously" priced over the past several decades.

Ideally a system should have/be a dual (or triple) fuel unit.

One really needs to do the math and look at YOUR specific installation, climate, insulation level and quality of the building construction, specific fuel costs - be they electric, NG or propane.

I don't think anyone expected or predicted last years run up of price on propane in many parts of the nation, while other parts were "normal"

 

[theoldwizard1]

One needs to understand that at one time or another, every fuel has been "cheaply" or "outrageously" priced over the past several decades.

Not true if you add the requirement of cooling. The most cost effective operational cost for heating AND cooling has been (and likely will be for some time) geothermal heat pump.

Ideally a system should have/be a dual (or triple) fuel unit.

Yes, "ideally". The vast majority of the US lives and works in a building that only has one source. My in-laws built a house in NC with an air-sourced heat pump, backed up by a couple of propane fireplaces. In 15 years, I think they were lit once, strictly for testing. Still a good back up.


The big issue with geothermal is how long will it take to pay back. This can be very long (or never) when your cooling season is very short, especially compared to a long heating season with NG readily available.

 

[RC_Dave]

I put it in about 10 years ago. It is a Water Furnace closed loop system with 3 wells 200 feet each. Used to have a heat pump, it paid for itself in about 3 years with savings over the heat pump. It also incorporates domestic hot water, so in the summer we take heat out of the house and put it in the hot water tank.

 

[woodzy]

One needs to understand that at one time or another, every fuel has been "cheaply" or "outrageously" priced over the past several decades.

Ideally a system should have/be a dual (or triple) fuel unit.

One really needs to do the math and look at YOUR specific installation, climate, insulation level and quality of the building construction, specific fuel costs - be they electric, NG or propane.

I don't think anyone expected or predicted last years run up of price on propane in many parts of the nation, while other parts were "normal"

I can say in my lifetime (55 years) the only utility that has been consistent is the electric company. It has always been high. Also, if you notice electric companies are building new generators fueled by natural gas - they must know that is the best and cheapest source of fuel in the future.

 

[Bookworm]

Also, if you notice electric companies are building new generators fueled by natural gas - they must know that is the best and cheapest source of fuel in the future.

The power companies are building Natural Gas plants for two reasons, neither of which is one you stated.
First - the EPA has effectively regulated coal plants out of existence. One can argue about the reasons, and argue about the effects on the environment, but the fact remains.
Second - there is no way in to-days political environment that a nuclear plant can be built.

I just read an article in my local paper, because of EPA regs, and the resultant order to install "scrubbers" on existing plants, we (customers of this utility) can expect rates to increase AT LEAST 20% in the next 4 years. Rates have gone up approx 15% just in the last 3 years.

I had the chance 10 years ago to install geo-thermal, costing roughly 50% more for a furnace replacement than what I ended up spending. I did not, thinking the payback would be too long (I calculated it to be 8 years).
I certainly wish I could go back in time and re-think that decision.

 

[CNGsaves]

^ ^ ^ ^ Don't believe all the FEAR MONGERING that electric utilities are throwing out about coal scrubbers being so astronomically expensive. Doesn't pass the smell test. Reduced demand for coal will drive DOWN input costs . . . plus, it's not that tough to retrofit a coal plant.

Really, how logical is it that coal scrubbers could be more than building an entire new plant ??? They've got one big exhaust stack . . . basically they are being forced to put "DEF tailpipe" on coal plant, just like diesel trucks now have. That surely won't take a rocket scientist !!

KS is pushing through another new coal plant, so they are still happening. Also note that effectively KS will be producing coal pollution to provide bulk of power sold to CO, NM, WY & NE !!
This is illustrious "accomplishment" of GOP's behind ***** Gov Sam Brownback who is also plunging KS into financial disaster (I call Brownback the BassAckwards Robinhood . . . Eliminate taxes for the Rich, and Increase taxes/Remove Services for the poor) !!
http://www.sourcewatch.org/index.php/Holcomb_Expansion
http://www.kansas.com/news/article1144680.html

 

[woodzy]

Second - there is no way in to-days political environment that a nuclear plant can be built.[/QUOTE

I am located just 15 miles from the Fermi plant in Monroe Michigan. Just last week, the NRC approved the license for a 3rd reactor.

http://www.detroitnews.com/story/news/local/michigan/2015/02/16/fermi-nuclear-plant/23487213/

 

[theoldwizard1]

...there is no way in to-days political environment that a nuclear plant can be built.

I am located just 15 miles from the Fermi plant in Monroe Michigan. Just last week, the NRC approved the license for a 3rd reactor.

That is only because it is being built on an existing nuclear power plant site using the same technology that has been used for over 50 years !

There are a lot of different ways to build a nuclear power plant. Many prototypes have been built, but few have gone beyond that to small scale production because the political environment in the US.

Fracking and increased natural gas production has extended fossil fuel, steam powered, electric generation in the US for a good 25-50 years, so research and development of new nuclear power technology has moved even further back on to the "back burner".

 

[theoldwizard1]

^ ^ ^ ^ Don't believe all the FEAR MONGERING that electric utilities are throwing out about coal scrubbers being so astronomically expensive. Doesn't pass the smell test. Reduced demand for coal will drive DOWN input costs . . . plus, it's not that tough to retrofit a coal plant.

If you mean retrofit for natural gas, you are correct. NG is killing coal and I am glad ! Sulfur scrubbers are one thing. Dealing with toxic flyash is another.

Check Duke Energy's record for the past 5 years or so. The are almost as bad as BP is in the oil industry.

 

[soapii]

$310 just for geo in a month is crazy, his house must be huge, or he doesn't have it programmed right (the secondary heat coil uses a lot of juice).

We installed geothermal when we built 2 years ago and yes we got the discounted meter (amounts to about 50% savings) and our monthly heating bills (in SE Michigan) are around $50-$75 during the winter. We keep the house at the same temp 24/7. The entire house was insulated with closed cell spray foam.

--Joe

 

[Bookworm]

Second - there is no way in to-days political environment that a nuclear plant can be built.[/QUOTE

I am located just 15 miles from the Fermi plant in Monroe Michigan. Just last week, the NRC approved the license for a 3rd reactor.

Getting a plant licensed, and getting a plant built are two entirely different things.

Also, try getting an all-new facility going. Ain't gonna happen, pal. There are still plants that were built 40 years ago that have never gone nuclear, never lit off. Moscow, Ohio has one.

 

[kj_mustang]

$310 just for geo in a month is crazy, his house must be huge, or he doesn't have it programmed right (the secondary heat coil uses a lot of juice).
--Joe

Or that unit has something wrong with it or was installed incorrectly. No way he should be having that high a bill.

 

[volleyball]

It seems to be his total electric bill. It could be that his groundsource is insufficient and the backup electric resistance is kicking in too much. Or the unit is programmed wrong.
A one month comparison is useless.

 

[theoldwizard1]

$310 just for geo in a month is crazy, his house must be huge, or he doesn't have it programmed right (the secondary heat coil uses a lot of juice).

We installed geothermal when we built 2 years ago and yes we got the discounted meter (amounts to about 50% savings) and our monthly heating bills (in SE Michigan) are around $50-$75 during the winter. We keep the house at the same temp 24/7. The entire house was insulated with closed cell spray foam.

--Joe

My son's gas and electric for his 1200 sq ft house was under $200 last month.

 

[theoldwizard1]

It could be that his groundsource is insufficient and the backup electric resistance is kicking in too much.

I am not a pro, but I have never heard of a electric resistance backup for a ground sourced heat pump. If such a thing was ever needed, the system was designed or installed wrong !

 

[Wardster]

My home, which was completed in 2004, has a closed-loop 4-ton geothermal system installed from WaterFurnace. Electricity powers everything in the house and my bill has averaged anywhere between $145-$175 per month in the ten years we have had the system. At the time of installation, the geothermal system we installed was almost double the cost of a propane unit ($9,000 vs $16,000), but we recovered that additional cost within four years based on the cost of heating with propane during that same timeframe. The highest energy consumption happens in the winter because of the auxiliary E-heat that has pushed our electric bill up into the $300 range, but it gets really cheap to operate during the other three seasons.

 

[Wardster]

I am not a pro, but I ave never heard of a electric resistance backup for a groundsourced heat pump. If such a thing was ever needed, the system was designed or installed wrong !

Most geothermal units have an auxiliary electric heater installed within the system for two reasons; 1. They act as your emergency heat source if something ever happened to the heat pump, and 2. They provide the heat pump with a little assistance on the coldest of days. At least that is the way it was explained to me.

 

[volleyball]

Most geothermal units have an auxiliary electric heater installed within the system for two reasons; 1. They act as your emergency heat source if something ever happened to the heat pump, and 2. They provide the heat pump with a little assistance on the coldest of days. At least that is the way it was explained to me.

That is right. Just like an air system to a far lesser degree, there may be enough demand that the system cannot keep up. To run the best, you run towards the minimum capacity needed instead of over compensating that you do with a fuel source.

 

[yeldogt]

I am not a pro, but I ave never heard of a electric resistance backup for a groundsourced heat pump. If such a thing was ever needed, the system was designed or installed wrong !

The systems I have been looking at all have electric back up. Some do it for setback/ vacation reasons so you can get the house back to temp -- equipment failure and also if the system falls out of design temps.

Evidently the coil systems can have this issue if the temps are low enough for a long enough time.

The costs of the wells around me can be upwards of 20k each -- If the system is going to fall out of design for only a few days per year the electric is a practical way to eliminate the last well.

 

[toplessHO]

open loop system with heat recovery for domestic hot water. I run sprinklers on a cycling valve to irrigate my yard,considering going to a "slinky"closed loop as the deep well also supplies my domestic water.Ive had ground source for over 30 yrs,only on my second unit(first one was purchased used so dont know how old it was). The key to any good system is good water source or if buried closed loop,good soil conditions.
Ponds and lakes are another source to consider tho they will fluctuate more than ground source. Im rural and have no other sources offered so this is the best choice for me.

 

[soapii]

I am not a pro, but I ave never heard of a electric resistance backup for a groundsourced heat pump. If such a thing was ever needed, the system was designed or installed wrong !

Most all groundloop geo systems have a backup (secondary) heat coil.

The only time I have seen our secondary unit kick on is if we turn up the thermostat more than 1 degree. So if the house is 66 and we up the thermostat to 68, then both systems will run to up the temp quickly. Our system was designed properly and works very efficiently.

--Joe

 

[woodzy]

It seems to be his total electric bill. It could be that his groundsource is insufficient and the backup electric resistance is kicking in too much. Or the unit is programmed wrong.
A one month comparison is useless.

His electrical was only the Geo system - total bill was $429.00 which includes the 2nd meter for the rest of the house electrical stuff. Temps in the last 20 days have not got above freezing. Last year his was slighty higher but the weather was even colder.

 

[JimL]

I put in hvac systems for a living in central indiana. Done some geo's but the vast majority is gas or electric with air to air heat pumps. Of the geo's we have done, all but one was a hybrid with gas backup.

If I were to build a house, I would put in a 2 stage air to air heat pump, High seer, with a gas furnace for backup.

My gas furnace didn't come on this morning, and my heat pump was cranking some heat out despite the 0 degrees outside.

One big negative for me with geo other than the cost is the fact that this afternoon its 30 and my heat pump is coasting in weather like this, and the geo would still be pumping 15 degree water through the loop trying to find heat when mines just coasting this afternoon. This late in the winter a geo has about pulled all the heat it can out of the ground...

 

[pseudorealityx]

I put in hvac systems for a living in central indiana. Done some geo's but the vast majority is gas or electric with air to air heat pumps. Of the geo's we have done, all but one was a hybrid with gas backup.

If I were to build a house, I would put in a 2 stage air to air heat pump, High seer, with a gas furnace for backup.

My gas furnace didn't come on this morning, and my heat pump was cranking some heat out despite the 0 degrees outside.

One big negative for me with geo other than the cost is the fact that this afternoon its 30 and my heat pump is coasting in weather like this, and the geo would still be pumping 15 degree water through the loop trying to find heat when mines just coasting this afternoon. This late in the winter a geo has about pulled all the heat it can out of the ground...

If it's a trench, then maybe... but deep wells will still be nice and warm. If they aren't, that's a design problem.

 

[volleyball]

His electrical was only the Geo system - total bill was $429.00 which includes the 2nd meter for the rest of the house electrical stuff. Temps in the last 20 days have not got above freezing. Last year his was slighty higher but the weather was even colder.

My temps have been that cold and bill is not there. I bet the electric coil is going on often. He can open the coil breaker and see what that does

 

[soapii]

One big negative for me with geo other than the cost is the fact that this afternoon its 30 and my heat pump is coasting in weather like this, and the geo would still be pumping 15 degree water through the loop trying to find heat when mines just coasting this afternoon. This late in the winter a geo has about pulled all the heat it can out of the ground...

Not in a closed loop system. The ground temp here is always 42-45*.

--Joe

 

[clarky456]

Current loop temp is a bit chilly at 40 degrees, unit (waterfurnace northern leader) has been running some extended cycles due the nasty cold spell. Highest bill is still way below the cost of propane, natural gas lines are miles away. Hoping to build some sort of high efficiency mass burner and depend less upon the geo during the winter. Endless domestic hot water during the summer, IF the A/C is on. 2450 sq ft, 2x6, triple panes, air exchanges low enough that Im looking into mechanical ventilation.

Joe

 

[toplessHO]

Not in a closed loop system. The ground temp here is always 42-45*.

--Joe

deep well temp is 74* year round for me
perfect for heat and cooling.
I have my flow adjusted to get about 89* discharge in summer and 55* in winter
my air discharge in heat mode is 114-115* with the return air temp @68*
thats some pretty good numbers for a 60K btu unit with about 25amps not including the well pump,which wont run all the time because of bladder tanks.

 

[JimL]

Not in a closed loop system. The ground temp here is always 42-45*.

--Joe

Not when the geo pulls that heat out. Even 6-7' down they will freeze with the geo pulling the heat out of the ground.

 

[JimL]

I will never understand why geothermal systems still sell around here. I put in a hybrid system in a house. 8 tons total, 2 systems, loop and all, took out oil furnaces. Just over $32k. Could have done the same thing with air to air heat pumps and been around $15-18K at the very most.

So less than half the cost. And in 20 years when its time to replace the heat pumps, he is going to spend double the money on geo again. Not to mention if he needs any repairs on the geos through the years. Water furnace is right proud of their parts.

So over the course of 20 years, is he going to save $18k on his utility bills? I think not. That would be what $70-80 a month he would have to save, every month for 20 years. I may be wrong didn't do the math, just in my head. $70 will buy a good bit of electricity in a month. I heat my house and garage for less than that even in the coldest months.

 

[theoldwizard1]

Most geothermal units have an auxiliary electric heater installed within the system for two reasons; 1. They act as your emergency heat source if something ever happened to the heat pump, and 2. They provide the heat pump with a little assistance on the coldest of days. At least that is the way it was explained to me.

Sorry, I don't buy either of those statements ! Of course I can not "prove" that they are wrong, but those statements are illogical.

"1. They act as your emergency heat source." The most likely failure of a ground sourced heat pump is lack of power from the POCO. Resistance heat would not solve that problem.

"2. They provide the heat pump with a little assistance on the coldest of days." That is the point of a ground sourced heat pump ! They NEVER need assistance, because they are using the "earth" as a heat source, The temperature of the earth is a constant 55F (+/-).

 

[theoldwizard1]

I put in hvac systems for a living in central indiana. Done some geo's but the vast majority is gas or electric with air to air heat pumps. Of the geo's we have done, all but one was a hybrid with gas backup.

Now that is perfectly logical ! Gas (either NG or propane) is a perfect backup. If you are using radiant heat or individual room air handlers with your heat pump, you could always use a couple of gas fireplaces.

If I were to build a house, I would put in a 2 stage air to air heat pump, High seer, with a gas furnace for backup.

I agree 100%. Assuming no NG available, I would even run be water heater, stove and dryer off of propane. The initial cost of of gas versions of those appliances is less and so is the operational costs.

One big negative for me with geo other than the cost is the fact that this afternoon its 30 and my heat pump is coasting in weather like this, and the geo would still be pumping 15 degree water through the loop trying to find heat when mines just coasting this afternoon. This late in the winter a geo has about pulled all the heat it can out of the ground...

If you are saying that the ground loop is feeding 15F water, then who ever engineered that loop screwed up big time ! Feed water should not vary more than 5-10F, season to season. Furthermore, it should NEVER be below freezing !!

 

[theoldwizard1]

Not in a closed loop system. The ground temp here is always 42-45*.

--Joe

Not when the geo pulls that heat out. Even 6-7' down they will freeze with the geo pulling the heat out of the ground.

Then it should have been installed at 15' or used a vertical well !

 

[Jackfre]

The day the tax credits go away is the day that geothermal dies. Geo is about the only energy credit for homeowners still on the books. Yes, it works and is efficient, but there are alternatives out there like the mini-splits that are chasing the operational costs of geo and doing it for a lot less up front. Also, when geo goes sideways it can get pricey in repair costs. I generally say to put the first dollar in the envelope and reduce the overall load for H&C. You then have more options. With Mini-splits in my 2200 sq ft here in the CA Foothills my highest electric bill has been $90 in the winter/summer peak. That is the H&C, well, lights, the works. I also have a Rinnai tankless and a Rinnai Energysaver DV. I went through 250 gal of LP in 13 months. In the shoulder season the Elec bill drops to $40.

One system I used to install with the geo was to put a glazed solar system on a swimming pool. We would heat the water and use it to power the heat pump. You need a good cover in the winter months and obviously not every climate can deal with this. In the summer for cooling we rejected heat to the pool and didn't use the cover. Pool chemical cost rise however and one fellow decided add a small cooling tower. These worked well back in the late 70's. I think most would rather have a pool than a couple wells or ground coils.

 

[theoldwizard1]

I will never understand why geothermal systems still sell around here. I put in a hybrid system in a house. 8 tons total, 2 systems, loop and all, took out oil furnaces. Just over $32k. Could have done the same thing with air to air heat pumps and been around $15-18K at the very most.

Location, location, location ! Lack of NG is also a big factor.

Geothermal heat pumps are only "good" solution in areas that have long cooling seasons or long heating seasons with no NG available. In both of theses cases, the near constant temperature of the water (+/- 55F) is the big win.

 

[theoldwizard1]

The day the tax credits go away is the day that geothermal dies. Geo is about the only energy credit for homeowners still on the books. Yes, it works and is efficient, but there are alternatives out there like the mini-splits that are chasing the operational costs of geo and doing it for a lot less up front.

That is a very strong opening statement, but I do agree that mini-splits are very cost effective, especially in areas where you do NOT have outside temperature extremes.

Some of the SE states have now mandated that all new public building uses geothermal heat pumps, because the operational costs are so low and they have long cooling seasons).

 

[DC73]

^ ^ ^ ^ Don't believe all the FEAR MONGERING that electric utilities are throwing out about coal scrubbers being so astronomically expensive. Doesn't pass the smell test. Reduced demand for coal will drive DOWN input costs . . . plus, it's not that tough to retrofit a coal plant.

Really, how logical is it that coal scrubbers could be more than building an entire new plant ??? They've got one big exhaust stack . . . basically they are being forced to put "DEF tailpipe" on coal plant, just like diesel trucks now have. That surely won't take a rocket scientist !!

It's much more costly than you think. About $500 Million dollars to convert one 30 year old 1000 MW coal-fired plant. But, it should still be done and if done correctly coal-fired power will remain competitive with the cost of other fuels. We're not yet at the point where we can abandon coal plants. There are too many of them. There is also a tremendous amount of coal still left in the ground (a 100 year supply by some estimates). The holy grail is for scientists to find a way to burn coal as cleanly as natural gas. They are working on it.

DC