Building a new house in upstate NY in the Catskill region. There will be a 100,000 gal pond right near the house. The cooling demand will be low and I already have a propane radiant floor system in place. I was thinking about putting in an earth tube system but then I thought I could dump a loop in the pond and use a geo system.

Any thoughts? The ground is cool and the pond is cool.

I'm thinking a closed loop out to the pond, a pump, a heat exchanger inside, a fan, and a condensate pan to catch the condensation from the heat exchanger. Who makes this?

Re-inventing the wheel or building a hybrid may not be in your best interest. a closed loop in a pond if not a metal plate exchanger is subject to biologic and physical damage. Why not do a pump and dump directly to the pond?
Eric

The system I was thinking of is a lot like what you would use for an outdoor wood boiler except for cooling. It eliminates the compressor and the refrigerant.

Pond will be too warm in the summer to provide sufficient cooling when you need it most. Rethink to whole approch. Betting on propane with a new house is pretty brave, to say the least.

Summertime dew points in NY are too high to rely on earth tubes, since the dehumidification capacity would be quite limited.

At 1k'+ altitude in the Catskills, a tight well designed house that limits summertime solar gain the seasonal cooling loads will be pretty low- low enough that the economics of springing for geo just for cooling don't make a lot of sense. But the economics of geo vs. heating with propane would probably have an economic rationale.

You might be able to employ a hydronic fan coil with well water dumped into pond, it would do much of what you hope but not all. Shortcomings would be in dehumidification.
Why not consider a water to water geo for heating and a hydronic air handler with the same geo for cooling.

Posted By joe.ami on 17 Apr 2012 01:16 PM
You might be able to employ a hydronic fan coil with well water dumped into pond, it would do much of what you hope but not all. Shortcomings would be in dehumidification.
Why not consider a water to water geo for heating and a hydronic air handler with the same geo for cooling.

The as-used efficicency of a kludged up groundwater system would likely be less than a window-shaker, and the cost getting onto that of a (dare I say it?) ductless mini-split air-source heat pump, that could also take a substantial bite out of the heating bill (even if not the total solution.)

Given the current (and projected future) cost of propane, the rationale for an all-geo solution is probably there. 

Betting on propane isn't as risky as you think, docjenser. http://www.lpgasmagazine.com/propane-industry-issues/growing-supply. Propane production in the Marcellus and Utica shale is set to take off. While experts still expect propane prices to track crude oil rather than natural gas, propane today can be as much as a dollar cheaper per gallon in producing states like Oklahoma than in distant states like NY. It is hard to appreciate what New England and the Midatlantic states gain when they move from the tail of the supply chain to the head.

Open loop geo dumping into the pond for hydronic heat and a hydronic air handler or mini-splits for cooling makes sense to me.

The vast majority of the propane production is a byproduct of the oil refinery process. That is why the price for propane in the last 10 years has very much followed the price of oil and is very much disconnected from the natural gas price. That is why the price of propane has almost tripled in the last 10 years, what are you going to do if it triples again, and chances are it will. While local supply and infrastructure issues affect the market somewhat, with propane we are on a global market, like with oil. If China,India and Brazil are willing to pay more for it, guess where it is going to be shipped? It is the same with oil. Producing more in this country will not bring prices down, we will just import less. With propane, we will simply export more. The global market will determine the price.

About half the propane on the US market is from oil refining the other is from "wet gas" pre-processing of natural gas for pipelining, a necessary step to ensure that condensation of the larger molecule hydrocarbons won't destroy compressors and other pipeline equipment. It's the end-uses (space heating & motor fuel) more than the sources that couple the per-BTU cost of propane to that # 2 distillates (diesel & heating oil). Since the latter are coupled strongly to the per bbl cost of oil, propane tends to track crude oil prices, but it's not absolute. Another significant chunk of propane end-use unrelated to space heating or transportation is the chemical industry, so it's not a hard-coupling, and the lower BTU/unit-volume of propane and the pressurized container requirement gives it a transport-to-market DISadvantage relative to heavier refined oil liquids- it's more expensive to handle & store, making it less amenable to large scale import/export than diesel or heating oil.

That factor makes it more of a regional than an international market, and regional variations in propane pricing is much greater than with heating oil, particularly near wet-gas well head pre-processing sources. While toddm is right, in the Catskills region of NY the development of the Utica & Marcellus shale gas (both formations produce gas with substantial wet-fractions) may put some downward pressure on propane pricing over the next decade or two but probably not enough to matter. The regional market for propane as space heating fuel is HUGE in New England & NY, unlike OK & TX sources, so the prospects for a DEEP local price depression aren't likely to be there, but there will be less propane imported from the southern region. Upward price hikes will be tempered.

The price of propane would have to fall by half to be cost-competitive for space heating compared with ductless air-source or geo at the current electricity pricing in that part of NY. The same regional gas strikes that will cap the price of propane will also put a price limit on the per kwh price of electricity. Regionally the bulk of new fossil-fired generating capacity is already running natural gas, even without carbon taxes. Propane for space heating might have been a rational choice when oil was $25/bbl (which wasn't that long ago), and before heat pump technology evolved to current levels of efficiency, but that market has changed irrevocably. Even with moderating factors limiting future per-BTU price increases, falling back to mid-1990s price levels (which is where it would have to be to compete with heat pumps) just isn't in the cards.

In fact, docjenser, half of US propane production is from natural gas. http://www.afdc.energy.gov/afdc/fuels/propane_production.html 10 years from now, natural gas will be by far the larger source, but prices will still rise and fall with crude oil prices because propane is readily stored and shipped.

But storage and shipping cost money. Turns out Oklahoma doesn't collect retail propane statistics so here are numbers from a state next door: http://www.neo.ne.gov/statshtml/86.html#graph

Home delivery prices in February in Nebraska averaged $1.67 a gallon, vs. $3.11 in New York: http://www.nyserda.ny.gov/en/Page-Sections/Energy-Prices-Supplies-and-Weather-Data/Propane/Average-Propane-Prices.aspx

If you look at the charts on the nebraska site you will see that the highest average price paid there since 2001 was $2.05 in 2008.

In short, prices are lower and less volatile the closer you are to production.

Motor fuel is the wild card in this part of the world. No less than 50 percent of the gasoline refining capacity in the northeast is shut down, for sale or both. With natural gas prices at 10-year lows, producers are targeting wet gas areas and thinking big thoughts about how to sell propane.

Sounds like Propane is the fuel of the future. I need to write this down.

I was referring globally to oil refinery as a source of propane, not just the US. The attached graph (thanks earth sensitive solutions) shows thatin New York State 1) The price for propane went up from $17 (per million BTU using a 82% efficient furnace) to $40. 2) It very reliably followed (curve by curve) the price of oil.
Since the price of oil is determined globally, I have not seen anything which would indicate that the connection between oil and gas prices would be disconnected.
At current prices, natural gas exploration is not profitable anymore. Many gas rigs are moved into oil exploration. The only way to increase natural gas prices is to reduce supply. Reduced natural gas production -> reduced regional propane production.

"The price for propane went up from $17 (per million BTU using a 82% efficient furnace) to $40. 2) It very reliably followed (curve by curve) the price of oil. "

...and with 18 cent electricity a mini-split with a seasonal average COP of 2.5 costs ~$21/MMBTU (roughly comparable with natural gas at regional residential rates.)

... and geo with a seasonal average COP of 3.5 costs ~$14/MMBTU.

Note also that it's heating oil costs, not crude oil prices in docjenser's attached comparison graph. There is significant coupling of crude/heating oil prices but it's not in lock-step by any means, also driven by regional refinery resources and competition for the same fraction of crude barrel with motor fuel. The rapid expansion of the market for diesel fuel in S. America has been a significant price driver in recent years, independent of the $/bbl of crude, with regional refineries getting into that market in a big way. (As of last quarter the US is now a net exporter of refined oil products due to the surge of south American demand.)

The price of natural gas will continue to be volatile over decade time period- it's a classic boom/bust type of business that I've watched at fairly close range. (I have a relative who has been in the gas exploration biz since the 1970s, currently working coal seam gas projects in Africa.) The sheer size of the local shale-gas resource will put an upper bound on gas prices, but not on propane. In the current market the liquid fraction makes or breaks the profit picture of shale-gas for any particular well.

I agree that nat gas to generate electricity + heat pumps is one of the top options - say for the next 50 years. Nat gas in cars should be far more popular than it is. PV solar is moving up the list. Ethanol and coal should be removed.

Gotta give you an A plus for wishful thinking, docjenser. The last natural gas bubble lasted for 20 years (1982-01) for a simple yet powerful reason. If you own the drilling rights on 100 acres in northeast Pa and you are surrounded by producing wells, do you wait, even though reserves are depleting by the hour, or do you get yours while the getting is good? Yes the rig count in Pa is down because there is less interest in exploratory wells and marginal areas. Development wells continue apace in good producing areas, as does the gas glut.

To be clear, I am not endorsing propane, for one, because I doubt that producers are paying the true cost of fracking. I am merely pointing out that docjenser's prognostication abilities are about as good as his understanding of the gas industry.

Posted By toddm on 19 Apr 2012 12:44 PM
Gotta give you an A plus for wishful thinking, docjenser. The last natural gas bubble lasted for 20 years (1982-01) for a simple yet powerful reason. If you own the drilling rights on 100 acres in northeast Pa and you are surrounded by producing wells, do you wait, even though reserves are depleting by the hour, or do you get yours while the getting is good? Yes the rig count in Pa is down because there is less interest in exploratory wells and marginal areas. Development wells continue apace in good producing areas, as does the gas glut.

To be clear, I am not endorsing propane, for one, because I doubt that producers are paying the true cost of fracking. I am merely pointing out that docjenser's prognostication abilities are about as good as his understanding of the gas industry.

And yet, there is discussion of capping currently producing gas wells that have lower than average wet-fractions.  The available storage capacity for natural gas isn't sufficient to handle the current glut during warm winters like this.  Even if you can get it out of the ground profitably, if you can't ship it and you can't store it, you're kinda stuck, and the pace of development (not mere exploration) has fallen off since the peak of a couple years ago.

But this kind of bottleneck is typical for production booms.  Storage capacity will increase, as will the size/volume of the market at these prices, but it all takes time.