What occured to me that might be interesting would be to identify and respond to some of the geo urban legends.
Hopefully we can keep the discussion non-politcal.

I'll start:
Gas Guy says: Everyone knows it costs more to meake heat with electricity. Just run some spaceheaters in your home and see how expensive it is......

Reality check: with geo you only use electricity to move heat around. you are not making it. therefore geo deliver an average 3.5 to 4 times the heat as an electric baseboard or space heater. What's more if you are around 10 cents per KWH and burning $2.00/gal propane, electricity may cost less to heat your home or hot water.

Throw in some fun ones and we may have the makings of a Letterman top ten list here.....
J

I have one, but it's probably going in the opposite direction that you're looking for. We had an estimate for geo in our new house. I knew that we were building a rather efficient shell so I didn't know if the upfront costs could be justified. The "economics report" that was provided showed that the break even point would be about 6 years. As I looked further into the numbers, it took some serious liberties. I think that the estimated gas costs were increased by 5%/year every year, but electric rates remained stabile. When I looked at the historic increases in our area & projected them forward, just the opposite was true - electric rates were increasing at a much higher rate than gas, and with those numbers it was something like 25 year payback.

This is not by any means a knock on geothermal - but in our case I feel that we were mislead, & I'm guessing that it's not that uncommon.

Myth: In order to properly size your Geothermal System, it should be able to handle 100% of the heating load reguardless of outside temperatures.

Reality: A properly sized Geothermal System should be able to handle 90% of your anticipated maximum heating load and have Auxiliary heat as a backup to cover the difference between them.  It's far too expensive to design a system that can handle exteme heating conditions that will only occur a few days every year. It's far cheaper to use electric reisistance heat for those few days. Yes it's more expensive to operate, with AUX heat, but the cost benifit ratio for a 100% designed system will never pay back the extra cost of the system.     

 

Posted By jerkylips on 05 Jan 2011 02:24 PM
I have one, but it's probably going in the opposite direction that you're looking for. We had an estimate for geo in our new house. I knew that we were building a rather efficient shell so I didn't know if the upfront costs could be justified. The "economics report" that was provided showed that the break even point would be about 6 years. As I looked further into the numbers, it took some serious liberties. I think that the estimated gas costs were increased by 5%/year every year, but electric rates remained stabile. When I looked at the historic increases in our area & projected them forward, just the opposite was true - electric rates were increasing at a much higher rate than gas, and with those numbers it was something like 25 year payback.

This is not by any means a knock on geothermal - but in our case I feel that we were mislead, & I'm guessing that it's not that uncommon.

jerky,
we'd have to see what you were presented with to confirm or deny.
I think most of the pros here have suggested more than once that geo is not a fit in every application. with tax credits available there would be no possible way in my area that geo would take 25 years to pay for itself. longest one i've seen recently in calculations has been 12 years (vertical system against nat gas). Not everyone enjoys our electric rates but....25?
need more info.
If your opinion of the contributers here is that we would divide payback by 4 I'm sorry.
suggesting it is common is also unfair to the pros here.
J

TG I'm more in favor of the 92-98% philosophy but as you know definately not of the "aux coil is the antichrist" mind-set.
Good to have you back.
j

TG I'm more in favor of the 92-98% philosophy but as you know definately not of the "aux coil is the antichrist" mind-set.
Good to have you back.
j

I'll re-post my ideas for those that don't read the geoexchange forum:

Who needs a "Manual J" when there are "Rules of Thumb"

You always need a buffer tank (just kidding.)

A hamster in the blower wheel will cost less over time than an ECM.

Loops in a graveyard will significantly reduce EWT .

You can use a WEL to predict ovulation.

A desuperheater will provide ALL of your hot water needs.

Regarding humidity and not knowing the geothermal system had a compressor, I had a neighbor ask me - "Isn't the air inside your house like the damp air in a cave?" - true story.

You need a lot of land for a geothermal system.

this was from a plumber.... not a heating contractor. That stuff doesn't work.... how can you get 120F out of 45F ground?

"You get the first 50 degrees for free, form 50 degrees to 70 degrees you have to pay for"

"You cant take heat out of ice!"

"There is no payback- Geo can't write me a cheque every month"

Adam

Posted By joe.ami on 05 Jan 2011 10:26 PM

Posted By jerkylips on 05 Jan 2011 02:24 PM
I have one, but it's probably going in the opposite direction that you're looking for. We had an estimate for geo in our new house. I knew that we were building a rather efficient shell so I didn't know if the upfront costs could be justified. The "economics report" that was provided showed that the break even point would be about 6 years. As I looked further into the numbers, it took some serious liberties. I think that the estimated gas costs were increased by 5%/year every year, but electric rates remained stabile. When I looked at the historic increases in our area & projected them forward, just the opposite was true - electric rates were increasing at a much higher rate than gas, and with those numbers it was something like 25 year payback.

This is not by any means a knock on geothermal - but in our case I feel that we were mislead, & I'm guessing that it's not that uncommon.

jerky,
we'd have to see what you were presented with to confirm or deny.
I think most of the pros here have suggested more than once that geo is not a fit in every application. with tax credits available there would be no possible way in my area that geo would take 25 years to pay for itself. longest one i've seen recently in calculations has been 12 years (vertical system against nat gas). Not everyone enjoys our electric rates but....25?
need more info.
If your opinion of the contributers here is that we would divide payback by 4 I'm sorry.
suggesting it is common is also unfair to the pros here.
J

Joe -

I ABSOLUTELY don't think that the contributors here would misrepresent, and you're probably right - my statement was probably too broad.  In any industry, there are going to be good & going to be bad. 

In our case, our house is not large, is really well insulated, and has lots of south-facing high solar gain windows.  Our heat loads are pretty low to begin with.  I posted something recently about our numbers, and overall gas usage last month was 5 btu/hdd/sq ft.  Taking into account gas stove, dryer, etc., I think 4 btu/hdd/sq ft is a fair estimate for heating.  That equates to probably $40/month to heat the house.  That's the reason the payback was so long in our case - because even with gas it's really low.

Again, sorry to make any generalizations about your field..

Here, I've got one;

Consumer: "Why are you charging 25% more all of a sudden to put in GEO systems?"

Contractor: "Don't worry about it, you can get 30% back via the tax credit."

This one cracks me up every time I hear any of their ads on the radio...

We were running ads on the radio promoting geothermal heat pumps.

A local HVAC "rule of thumb" (rule of dumb) company tried to combat our ads with their own radio spots. Their ad said: "with a gas furnace you won't have to pay for expensive electric heat to heat the air coming out of the ground".

They have absolutely no concept of geothermal. Also no concept of load calculations, duct sizing, furnace or A/C sizing, etc. There are many in our area that are of the same merit. However, others aren't as willing to broadcast their intelligence on the radio...

Some others I've heard

Myth: Copper will naturally corrode in the ground

Reality Check: Copper comes from the ground. Duh.

Myth: Direct Exchange doesn't work

Reality Check: We have hundreds of EarthLinked direct exchange systems in Utah. They work wonderfully well.

Myth: You have to have 55 deg. EWT or else the GHP won't work. (our school district maintenance man, who is outright ignorant to geothermal, and is so set on boilers it's not even funny)

Reality Check: GHPs can be sized and design to provide enough heat, even when the EWT temps get below freezing!

Myth: A refrigerant leak in the ground can contaminate ground water

Reality Check: HAHAHAHA! Refrigerant is a gas when at atmospheric pressures! It doesn't mix with water!

Myth: R-22 is less efficient than the newer refrigerants.....or R-22 will damage the ozone...

Reality Check: R-22 is a great, efficient refrigerant, and is HEAVIER than air...how does it get up to the ozone to hurt it? theory after theory after theory........ I guess theories = laws these days.


I was about to continue with some political ones, but I better stop there....feel free to ignore the last one. just venting.

Myth: Copper will naturally corrode in the ground

Reality Check: Copper comes from the ground. Duh.

Actual FACT: ...from The Copper Development Association. Double duh!!

http://www.copper.org/resources/properties/protection/underground.html

Myth: A refrigerant leak in the ground can contaminate ground water

Reality Check: HAHAHAHA! Refrigerant is a gas when at atmospheric pressures!

Actual FACT: Compressor oil is NOT a gas at atmospheric pressures.

Myth: ... R-22 will damage the ozone...

Reality Check: R-22 is HEAVIER than air...how does it get up to the ozone to hurt it?

Actual FACT: O2 is lighter than CO2. ...how does oxygen get down here so we can breathe it?

Actual FACT: R22 has a low ODP but a very high GWP -- and GWP is a problem at ANY altitude.

I guess theories = laws these days.

Uh, gravity is just a theory. Best to reserve judgement until all the facts are in...

...google: "intelligent falling"

Looby

Not really wanting to argue any points...just was venting a few views. I knew I was getting too political, anyway.

btw, I didn't say refrigerant oil.

btw, I didn't say refrigerant oil.

Urban legend: There's no compressor oil in DX refrigerant.

Argue, argue.....Why? It seems you have something against DX. Fine, I'll argue.

The amount of compressor oil in the DX system is very minimal. It will contaminate the ground water to a much lesser degree than the amount of methanol in many water loops. Refrigerant won't contaminate the groundwater.

We started with geothermal in 1995. Initially, we did water source. In 2001, we switched to EarthLinked. I used to hold a grudge against water source heat pumps and their supporters. They won't give DX time of day. My grudge was pointless. EarthLinked DX has been a great success for us. I've seen botched up EarthLinked installs; I've seen many more botched up water source installs. Typically it's because of short-looping the system. But hey, the biggest advocate in Utah of water source heat pumps just puts boilers in the loop circuit. It's CYA I guess...

Urban Myth: The brand and type of my geothermal system is the most important part of my geothermal decision.

Reality Check: The installer is more important, hands down.

Anyway, there's no point in arguing which type is better. The fact is that there are many myths about DX geothermal that are put out there by water source supporters. You can't and won't convince me that EarthLinked systems won't work. You can't convince me that water source systems won't work, either. In fact, it would be stupid of any of us to try to do so.

It's still a myth that copper will just naturally corrode anywhere in the earth. In acidic soils, (5% of the land area of the lower 48 states) it will naturally corrode. However, in the other 95% of land area, it won't. Copper.org is a great website to learn all about it. How about a measurement worth more than opinions...the statue of liberty, made of copper, has oxidation how deep? .005" into the copper. And it has stood there how long?

Arguing just to argue is asinine. argue away...

How 'bout-
"now that air source can go down to 0* there's no reason for geo"

How 'bout-
"now that air source can go down to 0* there's no reason for geo"

The newest ASHPs work fine down to half of that temperature.

The newest ASHPs work fine down to half of that temperature.

That's sort of confusing because half of 0F is -230F.