Duplicate post deleted by Looby.

Quote: . . . I will embed the heating wires under the ceramic tiles quite close together about 4cm (less than 2" apart) so the heat distribution will be uniform. . . . What is the life span for heating wires under tile or in concrete slabs? I would suspect that pex water lines will last much longer.

"Sounds like some difficult-to-quantify costs -- typical of ambitious
DIY projects."

My PV solar heating is a bit of a different story but even using grid power directly at 12 cent /kWh mentioned here is better.
The geothermal example that was presented here will need about 26 amortization time and that is a bit of an optimistic number.
 

"-- thus getting
the installation completed in less than 2 months. Compared to a
DIY schedule, the "amortization clock" starts running years earlier."

The only reason I can not start ruining my PV heating right now has to do with the fact that I do not have the money.
The PV install is extremely simple and I can do all that in a week the restive loop will be another week probably because ceramic tiles will be installed above them.
There is the MPPT controller that I need to design and build (but this is what I do anyway) the project will be open source HW and SW and probably some units will be available trough Kickstarter next year.
This PV heating is just my choice at the moment but it may become more popular soon.

I'm sure most people on this forum do a lot of DIY work else they will probably not be here.  

Posted By electrodacus on 19 Mar 2015 08:46 PM
The only reason I can not start ... restive loop will be ... ceramic tiles will be ...
the project will be ... some units will be available trough Kickstarter next year.

Lots of future tense. Unfortunately, cost savings are not retroactive,
and early capital expenditures will have reduced (or zero) payback
until something much closer to a completed system is in operation.

Have you included "temporary" propane expenses in your payback
time calculations? How does your home's comfort level last winter,
and this winter, and next winter, and, and, and... factor into the
amortization analysis?

...yes, time really IS money,

Looby

"Have you included "temporary" propane expenses in your payback
time calculations? How does your home's comfort level last winter,
and this winter, and next winter, and, and, and... factor into the
amortization analysis?"

I know I'm losing money by using the temporary propane heater. There is no other way for me since I do not have the 10K$ to invest at tis moment.
I used 43 small propane tanks this winter that alone is about 1300$ instead of 400$/year amortization with PV.
Comfort is not a problem was excellent especially this winter. Last winter was the first here and many things where finalized during that time.
The cost of the propane heater is really low since I did not invest in quality parts is just a temporary setup.
The propane heater is one of those cheep tankless water heaters was 160$ including shipping like this http://www.ebay.ca/itm/321695624148. I also use a small heat exchanger another 130$ then 3x 24V DC water pumps for coolant and water circulation about 120$ for all 3 (I do not remember the exact price but I can reuse those).  Some short rubber hoses a few more dollars a 20$ 200liter (55 gallon) barrel some fittings.
This works at most a few hours / day in average about 3.5 to 4 hours but there are also days with no heating at all do to strong winds and the DIY forced ventilation not able to keep the fame ON but those are just a few days / winter at most. Some times is warmer and heating is not needed. Lowest temperature was 16C in the morning and highest about 22C. With the current setup is hard to heat above 22C. Average is around 19C to 20C most of the time. There is a large inertia for heating do to large thermal mass but also cooling is not fast 3 days with no heating is not a big problem.

Geothermal is not inexpensive when compared to direct electric heating and geothermal seems to need 26 years to recover the investment in a bit of an ideal estimation.
It is hard to say if price of electricity will go up or down in the next years but at those 12 cent current price that is the amortization time 26 years.

"Question is will a geothermal installation (DIY as much as possible) make sense in this situation where I can save about 5000$ by installing only 3kW array instead of the 9kW needed for direct electric heating."

Actually your question is "Is Geothermal Heating obsolete ?" Which is why you are getting so much push back. BTW 3K costs the same as another 6 K and heating equipment?....or are we skewing the math again?

"Most people are not able to calculate a cost amortisation else there will have been some answers to my question."

Heck I can't even spell it.......when one cherry picks numbers the cost can be whatever you want it to be. That said, given current tax credits, most of my systems repay my propane or fuel oil clients back in ~5 years. The short hand is ~$20,000 installed less $6,000 in tax credits and savings of thousands each year. These are retrofits and houses of some size, not superinsulated cottages.

"Cooling is also used here by probably over 90% of houses. Bad design with no thermal mass and little thermal insulation.
Question was about geothermal heating only but you can include a cost amortisation for cooling and compare that with a less expensive air to air cooling."

Yes you want to exclude cooling in the equation but use water distilation? You can get geo without cooling and in many cases it will trump pv direct, just not yours. And BTW there is such a thing as "super insulated" envelopes that require cooling in the winter.

"You can say something is obsolete if there are more cost effective methods to do the same thing."

You can "say" whatever you like, but it doesn't make your definition valid. What about this one from wiki "Obsolescence is the state of being which occurs when an object, service, or practice is no longer wanted even though it may still be in good working order. Obsolescence frequently occurs because a replacement has become available that has, in sum, more advantages than the inconvenience related to repurchasing the replacement. Obsolete refers to something that is already disused or discarded, or antiquated.[1] Typically, obsolescence is preceded by a gradual decline in popularity."
I think we might argue that geo is actually gaining in popularity, not declining.

"The thing is that geothermal will not work for me more complexity higher cost so no gain."

Could be exactly right, but still does not make geo "obselete".

"So is a geothermal installation a cost effective solution? I think this is the best place to ask this question since many of you have a geothermal installation and know the real cost."

And many of us have told you yes and have also said "not in every application".

"If the geothermal runs at an average COP of 3 and you bill is $68 then you probably have a saving of $136 / month in winter compared to using electric directly.

With a geothermal with real average COP of 3 the saving from 12 cent /kWh electricity is about 8 cent/kWh and as I mentioned that will need about 26 years with no additional expenses to amortize the cost of geothermal.

I think at best the COP is 3 not sure he included all the parameters in his evaluation."

How easily you discard this in your weather zone: "My end of season COP on my geo system is 3.8, with a start of 4.5." That should put the average closer to 4 don't you think? This is another reason you continue to get push back and accused of cherry picking numbers.

"Not a fair comparison even if you got cooling cost included. Since it may be that most of the saving is from additional thermal insulation and not geothermal."

Did the additional 500 SF also save on the heating bill?

"So if I use electricity from PV to produce distilled water I save 700$/year and if you remember the amortization cost of PV array was 400$/year for 25 years so it more pay for it self just by making distilled water so the heating is free."

It doesn't matter that geo can cool and make hot water, but you can distill water???!

"So you can see for me PV heating is way more than superior to geothermal."

Okay many have suggested that may be true but that is different than geo being obselete.

"Have you included "temporary" propane expenses in your payback
time calculations?"

Lest we forget how is the abandoned bio diesel working on this payback scheme. BTW does this mean bio-diesel is obselete?

You might be an engineer but you are definately not a good canidate for debate team. Those folks tend to support their arguments.
A reasonable researcher uses more than one sample to draw a conclusion (thus avoiding allegations of "cherry picking").

The devil really is in your choice of words, supporting evidence and your insistance on repetition as though it will make your assertions true. Had you asked "does geo work at my house"
we all might have agreed with your conclusion.

This is all kind of ridiculous. I am heating a house 5+ times the size of yours for $920 Nov- March. My 2 car garage is 700 sq ft.

When I built the house, which saying that does not mean the same thing as you saying you built your house.
I had to get plans drawn up, get septic system designed, plumbing permit, electrical permit, mechanical permit. Building officials had to sign off on multiple steps along the way.

I can't tell from your video if you have anything more then an insulated cabin. No well, no septic(composting toilet?) running water. Seems like camping.

The way I looked at it when I put in the GSHP was a house has to have a heating system, the only amortization of the money spent was the amount over the cost of a traditional system, whether it be an oil system or propane since we have no natural gas available.

I also commend you on building an efficient house. You could probably heat it with this CERV http://buildequinox.com/products/cerv/ A ventilation system with a heat pump in it.

I will embed the heating wires under the ceramic tiles quite close together about 4cm (less than 2" apart)

Exactly where you don't want them if you want to maximize the use of the concrete slab for thermal storage without overheating the room.

Posted By joe.ami on 20 Mar 2015 09:11 AM
That said, given current tax credits, most of my systems repay
my propane or fuel oil clients back in ~5 years.

Exactly! My retrofit will pay for itself in under 10 years, even though
it required new ducting throughout and a 450' grouted borehole.

The inside stuff is fully warranted for 10 years, and the in-ground
pipe will outlive me by decades -- so no wurries in that score.

Of course, tax credits and low interest financing become somewhat
problematic for multi-year DIY evolutionary experiments.

...time is money, so jus' git er done!

Looby

Posted By electrodacus on 19 Mar 2015 09:55 PM
... geothermal seems to need 26 years to recover the investment in a bit of an ideal estimation.
It is hard to say if price of electricity will go up or down in the next years but at those 12 cent current price that is the amortization time 26 years.

Similar to Looby's 10 year payback, our retrofit will pay for itself in under 12 years.  Continuing to stress 26 year recovery is folly.

This is a long replay thanks for taking the time. I will try to add my comments hope I do not miss anything.

"Actually your question is "Is Geothermal Heating obsolete ?" Which is why you are getting so much push back. BTW 3K costs the same as another 6 K and heating equipment?....or are we skewing the math again"

Yes that is the main question. I know geothermal will not work for me. But I do not see it working for those that have grid power at 12 cent/kWh maybe at 40cent/kWh will make more sense do to higher savings more rapid recovery of investment.
I see here people talking about switching from heating oil to geothermal and comparing the saving. This is not a fair comparison since heating Oil was more expensive per unit of energy that electricity.
What is a fair comparison is a direct electric heating and an air to air heat pump for cooling way less investment than geothermal then compare the time you need for extra cost of geothermal.

"Yes you want to exclude cooling in the equation but use water distilation? You can get geo without cooling and in many cases it will trump pv direct, just not yours. And BTW there is such a thing as "super insulated" envelopes that require cooling in the winter."

Thing are quite different. Making distilled water in winter will not take anything from heating and in summer if you do not use the energy available is just lost energy.
Cooling can be done with geothermal in about the same way it can be done with a simple air to air heat pump the difference in deficiency can be included but will be really small the difference in investment is extremely significant. So saving are way more significant for heating than cooling.
And that water disinflation thing I included later just to show the advantage of PV over thermal solar for example where the output energy is electricity and not heat and excesses can have more uses.
If my house needed cooling I could have gotten an inexpensive air to air heat pump and use the electricity form PV to cool the house with the same 400$/year amortisation cost actually 450$ to allow for a good quality $1200 air to air heat pump.
 

"Obsolescence frequently occurs because a replacement has become available that has, in sum, more advantages than the inconvenience related to repurchasing the replacement"

This is the part of the definition I'm referring to. If you already have a geothermal installation then there is no better option for you at this point. But if you do not have one and you are thinking on getting one then there are better options in my opinion. If grid electricity is 12 cent as it was on the single real example here then amortisation cost for his installation is a bit to long 26 year and this done not include cost of maintenance and repairs.

And many of us have told you yes and have also said "not in every application".

I'm an engineer I'm not happy with just an yes or no answer I want the numbers (all numbers).
There was only one person here that has done that.

"How easily you discard this in your weather zone: "My end of season COP on my geo system is 3.8, with a start of 4.5." That should put the average closer to 4 don't you think? This is another reason you continue to get push back and accused of cherry picking numbers."

Can you give more detail how did you calculated the COPin your system? It is for sure possible but a bit unlikely unless the ground loop is oversized quite a bit so that will have needed a higher initial investment. So I will need a lot of numbers from you to demonstrate that 3.8 to 4.5 COP. No worries I made a lot of thermal calculations so is no problem for me.

"Did the additional 500 SF also save on the heating bill?"

The additional thermal isolation can more than compensate for that small increase in living space. So without knowing how bad was the old building insulated and how much the new one has I can not form a good opinion.
But I'm quite sure it was a net reduction of the house energy use. Not having real numbers I can just speculate.


"Lest we forget how is the abandoned bio diesel working on this payback scheme. BTW does this mean bio-diesel is obselete?"

Bio-diesel was more cost affective and continent for me than propane problem was the heater that I had failed and replacement for that did not made sense at that point since I knew at that point I will do PV heating.
I did not know about PV heating when I purchased that Bio-diesel heater (I was able to resell that for parts and recover the investment that was not to large to begin with)

"You might be an engineer but you are definately not a good canidate for debate team. Those folks tend to support their arguments."

I did the arguments. For me things are simple no matter the house size or level of insulation you need a numbers of units of energy each year to heat and cool your house. All you need to know id the cost of each unit of energy to compare any option available.
For my location
1) Propane 28 cent/kWh + equipment mortification (about $700/3 years = $233/year) total energy used / year 4500kWh another 5cent/kWh so total cost of this temporary heating solution 33 cent/kWh.
2) Diesel 9 cent/kWh + equipment about the same cost and amortization time as propane so total 14 cent/kWh
3) Solar PV 10K$ initial investment in equipment with 25 years amortization time and no cost for fuel since sun is free for now :) so 10k$/ 25years = 400$/year 400$/4500kWh = 8.8cent/kWh.

All this are DIY but you may not prefer that so need to add the cost of installation. Also fuel may have a different price at your location and sun may have more or less radiation in winter affecting the amount of solar PV you need and the cost/kWh.
Hope is clear that house size, thermal insulation or climate are not factored in to the cost of energy.

This is all kind of ridiculous. I am heating a house 5+ times the size of yours for $920 Nov- March. My 2 car garage is 700 sq ft.

That is a fantastic cost for heating but where is that located ? the cost of heating depends not just about the cost / unit of energy but also climate. And you did not included the initial investment and maintenance cost of the geothermal.

Also this is a DIY house it will have all the utilities it just takes time it can not be done as fast as if a large team works on it.
There is rain water collection and storage there is a composting toilet and there will be a holding tank with evaporator for grey water (I will go in to details about that when is done).
I have all the necessary permits but things are less stringent on a 20 acre lot in the middle of nowhere. Still we are discussing here about the geothermal heating cost so I will stop here.
If you have geothermal with an average COP of 3 and your electric bill for heating is 920$ assuming the same 12 cent/kWh you use 23MWh/year for heating where I use 4.5MWh so I will say my house is better thermally insulated.
A 5x smaller house with same level of insulation will not use 5x less energy do to the fact that the envelope area is not 5x smaller.

"Exactly where you don't want them if you want to maximize the use of the concrete slab for thermal storage without overheating the room"

This method is used extensively for in floor electric heating. I only have at most 100W/sqm or 9w/sqft for just 4 or 5 hours /day there will not be any overheating of the room. The heating wire is also extremely close spaced making the floor uniform heated.
For a house less insulated that needs more heat this will not work with PV but it may work with grid electricity since there you can heat for 24h at constant rate not just 4 to 5h.
I do have a water storage tank installed already that can store up to 30% of the daily solar energy and that can be circulated by a small DC pump trough the PEX pipe that is embedded deeper in to the concrete. I do not think I will need that part but is there if I do.
There is not much PEX it is spaced a bit far so that can only take about 4 to 5kW depending on the concrete temperature maybe a bit more in the first half hour. I can see hot spots on concrete with a IR thermometer even if the PEX is quite deep in to the concrete floor.
Room air temperature can not be above the concrete surface temperature if that is the only hefting source and that will stay below 27C at all times.
But thanks for the concern that was a legitimate concern.

"Exactly! My retrofit will pay for itself in under 10 years, even though
it required new ducting throughout and a 450' grouted borehole."

How much was that 450' borehole? Was the ground easy to drill in to no rocks ?
How long is the loop (400'x2) what sort of pump do you use and what flow rate do you have. Also what is the input and output temperature?.

"The inside stuff is fully warranted for 10 years, and the in-ground
pipe will outlive me by decades -- so no wurries in that score."

I'm sure the ground pipe can survive for decades there is no reason for that to fail.

"Of course, tax credits and low interest financing become somewhat
problematic for multi-year DIY evolutionary experiments."

I never considered tax credits. Are there good tax credits for geothermal ?
I find the tax credits a bit of cheating but if the government will pay say 100% of the installation cost :) then there is no competition to geothermal.


"...time is money, so jus' git er done!"

That can be true I care less about money and more about doing what I love to.
If I wanted money I will have lived in a large city with a good job at a large corporation.
All I try to do with the passive house and no utilities is reduce the expenses as close to zero as possible.
But I'm getting off topic.

"Similar to Looby's 10 year payback, our retrofit will pay for itself in under 12 years.  Continuing to stress 26 year recovery is folly."

He had two choices. One geothermal and the other direct electric heating. His savings for direct electric heating need around 26 years to amortise maybe a bit less since direct electric heating will also have had some small investment but really small compared to geothermal.
It is not fair to compare the older uninsulated house with an old oil furnace with geothermal. Oil was more expensive per unit of energy than electricity and I have no idea how much the difference is from thermal insulation.
  

Posted By electrodacus on 20 Mar 2015 02:33 PM
How much was that 450' borehole?

Something like USD $8000 -- don't remember exactly, 6 years ago.
That included: drilling, grouting, 1000' x 1.25" HDPE pipe, 50' x 6'
trench to house, through-slab drilling and fittings, site clean-up.

Was the ground easy to drill in to no rocks ?

Happily, NO! Hit rock at about 8 ft. depth, solid rock all the way down.
Heavily fractured, water-saturated, schist with a few sand and gravel
inclusions and 2-3 underground streams. Absolutely ideal conditions
for closed-loop geothermal. Rock w moving water is geothermal gold.

The trench to the house was interesting, they ran into some SUV-size
boulders. But no big deal, professional geo well installers expect
that around here -- no extra charge, it's included in the contract.

I never considered tax credits. Are there good tax credits for geothermal ?

Didn't consider?? Maybe you should ease off a little on the evangelical
"most people are not able to calculate a cost amortization" sermons.

The US government has a 30% geo tax credit, and some state and/or local
governments have additional credits/grants/incentives. Credits are are also
available for most other energy-conserving technologies -- but I suspect
that the certification requirements might be an obstacle for DIY-ers.

NO credits or incentives for (on-grid) electrical resistance heating.

Ultra-low interest HELOC money is also available -- with (after tax) APRs
below the rate of inflation. That allows a financially numerate homeowner
to install NOW and begin reaping the benefits immediately, while deferring
repayment until later (with cheap, inflation-eroded dollars). Amortize that!

If I wanted money I will have lived in a large city with a good job at a large corporation.

So, is "income opportunity cost" factored into your amortization analysis?
Obviously, you're willing to forgo income to pursue DIY interests -- but
most folks would happily expend cash to AVOID that particular hobby.

It seems rather silly to insist that nothing counts except $/kWh -- while
simultaneously arguing that it's non-monetary values and priorities that
justify your efforts AND (by implication) that your values and priorities
trump everyone else's.

"Nicht alles was zählt, kann gezählt werden, und
nicht alles was gezählt werden kann, zählt!"
-- Berty E.

"Something like USD $8000 -- don't remember exactly,"

That is fantastic way better than I expected. There is no way I can get the same done here even at 2x that price.
Do you have some numbers on the flow rate and temperature difference you can get from that single loop?

"Didn't consider? Maybe you should ease off a little on the evangelical
"most people are not able to calculate a cost amortization" sermons."

I was not thinking at tax credits there are probably also some for PV solar but I did not took tax credits in to calculation.
Of course if you can get those tax credits it needs to be used in the calculation.
I do stand by my affirmation that most people (not all of course) are not able to do cost amortization calculation. I'm not referring just at heating is just a general observation. 

"It seems rather silly to insist that nothing counts except $/kWh -- while
simultaneously arguing that it's non-monetary values and priorities that
justify your efforts AND that your values/priorities trump everyone else's."

Yes I do think $/kWh is an important indicator when comparing different energy sources .
I do not want to compare my particular case with others or DIY vs none DIY.

Cost analysis needs to be done based on each case and location.
Where natural gas is availably that may be the best option for heating since usuals that is around 3 to 4 cent/kWh and hard to beat at the current price.
Usually you use electricity from the grid to power the heat pump so a good comparison can be done between using electricity directly with inexpensive convection heaters or electric water heaters + low cost air to air heat-pump or a similar combination vs the extra expense of geothermal heating. Geothermal will have some savings for heating about 66% (COP 3) vs direct restive electric heating and for cooling savings are probably much smaller maybe 10 to 20%.
So all is needed is to calculate the amortization cost of that extra investment in the ground loop and heat pump vs the investments in AC and resistive heaters. If there are maintenance cost those should also be included for both methods.
Also it seem that people did not noticed the question mark in my thread title. I'm not saying geothermal is obsolete I'm just asking if it is. I'm here to do the negative argument and I expect to be contradicted with real numbers.
Of course geothermal will be highly dependent on material and installation cost at your location and dependent on the cost of electricity. 

I think the best way to see things from my perspective is like this. Say you have a business that is an energy power plant. You have a few options say just electric or geothermal and you need to provide heating for a number of homes and you need to charge them / unit of energy delivered can be kWh, BTU or whatever unit of energy you prefer.
But in order to calculate a price you need to charge them for you to be profitable and competition not to take your clients with a better price.

Posted By electrodacus on 20 Mar 2015 04:58 PM
Do you have some numbers on the flow rate and temperature difference you can get from that single loop?

Data from 2009 thru 2011, in Philly 'burbs
(stopped paying much attention since).

Winter EWT: 37°F to 45°F.
EWT - LWT: 6.5 to 7.0 °F
Loop flow: 7.8 to 8.0 GPM
Circ pump: Grundfos UP26-99

On-grid electric rate? I really don't pay attention anymore...

...compared to fuel oil, it's "too cheap to meter,"

Loony

"Winter EWT: 37°F to 45°F.
EWT - LWT: 6.5 to 7.0 °F
Loop flow: 7.8 to 8.0 GPM
Circ pump: Grundfos UP26-99"

8GPM (about 1800liter/hour) with a delta of 7F (about 4C)
Not sure what liquid are you using since is close to freezing maybe is not water.
But I will take water since that will give a more optimistic number.
Water is at 1.12Wh per liter and Celsius so
1800 x 1.12 x 4 = 8kW (about 7kW if this is glycol)
Now I do not know how many hours this works or what is the average flow rate for 24h in winter and temp delta.

Assuming this works at this rate 24h a day your house will use 5760kWh/month of heat. (not an unrealistic number but is probably lower since there is some temperature control and it will not work at full power all the time)
In order to find out the average COP you will need to monitor (data logging) the loop flow and temperature delta and also the electricity usage strictly for all equipment related to the geothermal pump.
Then if all the equipment is inside the house (pumps, heat pump) you can divide the electricity used to the (electricity used + input energy "the one calculated from loop flow and temp delta") and find the average COP.


"...compared to fuel oil, it's "too cheap to meter,"

:) If electricity was at 40cent/kWh or more like in some places you will not say is to cheep to meeter.
Oil has had quite a large fluctuation so is hard to say what the price will be but usually equal or quite a bit more than electricity in most places.
It also depends on the oil burner efficiency that can be quite low in some cases.
More fair comparison is electricity vs geothermal and see how much time the geothermal needs to recover the investment.

I was expecting someone has done a more scientific test related to cost amortization of geothermal for a typical installation so that you can say from what price/kWh for electricity it make sense or not to have a geothermal installation.

Here is another geothermal data point for you:

My new home heating load is ~30,000 BTU and cooling load is ~26,000 BTU (2150 sq ft ICF over 1500 sq ft ICF basement). I sized my loop field for these loads and a Climatemaster TE 038 (3 ton 2 stage geothermal package unit with variable speed loop pump included). I used the Climatemaster Geodesigner program for the loop sizing.

3 vertical bores, 4.5" diameter x 230' deep, plus 20' of trench to the house. I can rent a trencher for ~$100/day to dig the trenches to the house. The cost for drilling and grouting the holes is $6/foot or $4140. The geothermal pipe (HDPE 3/4" x 510' with pre-installed U-bend) locally costs ~$160 per loop or $480 total. I'm estimating another $300 or so for inside header, valves, and piping to get to the geothermal unit. A Climatemaster TEV038 unit costs ~$7400 delivered. That is a total cost of ~$12,500 for a 3 ton 2 stage geothermal excluding ductwork and thermostat which I also plan to DIY. Given the current 30% tax credit, my net cost will be ~$8750.

Per the Geodesigner program, my local deep earth temperature is 63F with minimum EWT of 42F and maximum EWT of 96F for the above amount of load and loop given the expected geology (~30' of clay overlaying saturated shale with intermittent sandstone).  Annual average heating COP was 4.80.  A good portion of my hot water would also be generated by the heat pump.

My electricity cost is ~10.5 cents / kWh all costs included.  Geodesigner estimated an average monthly heating / cooling / hot water cost of $59 or $705 per year.