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  1. #14
    Join Date
    Feb 2012
    Location
    New York City
    Posts
    106
    First cost and design cost has always been an issue with GSHP. If its cheap and easy to put pipe in the ground where you are, GSHP is great, but you need to make sure you have enough pipe in the ground. That's not easy. You need someone who understands local hydrogeology well.

    ASHP performance on an annual basis is worse than GSHP but closer than you'd think. ASHP performance is also easier and cheaper to accurately predict. If you're looking to combine water heating I'd look at Daikin Altherma or the hydronic attachments to mitsubishi's city multi system. Both of those systems have good low ambient performance.

    I think something like the Altherma would be a cheap and easy "bolt on" solution to your energy cost issue by adding a hydronic coil to the existing propane furnace system (probably in place of your existing DX cooling coil). On the DHW side you could put the Altherma DHW tank in a preheat position in series with your existing and run your recirc to the Altherma tank if youre not comfortable with peak day performance and want to minimize your capital costs now.
    I hope I helped!

    Feel free to contact me and other users here for more detailed assistance within the context of a contract. Advice and opinions are provided here "as-is" without any warranties, guarantees or acceptance of liability for use, misuse, or accuracy of advice given. (Gotta keep my legal team off my back at work.)

  2. #15
    Join Date
    Apr 2012
    Posts
    19
    Interesting, very interesting. I googled Altherma and it looks like it's a inverter heat pump boiler? I'm trying to understand how that would work with my force air ducts though? Use a water to air heat exchanger? Or would I have to put those fan coil units in each room? Thanks

  3. #16
    Join Date
    Apr 2012
    Posts
    19
    Sorry, I re-read your post and you explained it already, add a hydronic coil to the propane system. So I'd use my existing ducts. I could probably easily add a zone to the basement also with a fan coil. I will contact a local Daikin dealer, thanks.

  4. #17
    Join Date
    Feb 2012
    Location
    New York City
    Posts
    106
    If you went with Mitsubishi, you'd put small DX fan coils in each room and a hydronic heat exchanger on a recirc loop with domestic. They have a product called HydraDan that's just like Altherma but not available in the US.

    Make sure you understand how the Altherma system wants to operate on the hydronic side before doing this. It looks more like a commercial two-pipe hydronic system to your terminal equipment, except add on the complexity of DHW priority during both cooling and heating. It will affect the piping layout. Basically you want to keep the tees going off to the Daikin DHW tank close to the hydrobox so that there isn't a big cold slug when it changes over for DHW priority in the summer and a big hot slug when it goes back into cooling once the DHW call is satisfied. Also I would suggest using three port valves on your water to air coils so that you keep a decent mass of water moving through the refrigerant to water heat exchanger. Speaking of those coils, size them based on 105F entering water in heating for best performance.

  5. #18
    Join Date
    Feb 2009
    Location
    Portland OR
    Posts
    2,030
    Maybe your area is much different than mine but an Altherma costs MORE than geothermal where I am and does not receive a tax credit. I can put in a vertical bore or horizontal bore(about $18 per foot in my area to drill) for the cost of an Altherma and still have higher performance. Just something to consider.
    Check out my YouTube channel - http://www.youtube.com/user/skyheating1 We have customer testimonials, product reviews and more!
    Like us on FACEBOOK if you like our advice here!

  6. #19
    Join Date
    Feb 2012
    Location
    New York City
    Posts
    106
    At nominal 200-250 of borehole ft/ton equipment, that sounds like it would be 20 to 25 k to drill plus equipment and installation less the tax credit. Which isn't bad, I guess. I'm not sure how much Altherma systems are running per ton, and in propane territory you should have lots of skilled people who can make big holes in the ground for a reasonable price. So it's something to consider.

    I've dealt with a bunch of site constrained closed loop projects and drilling ends up being expensive and logistically constraining the balance of activities on site. Worse, I've had a bunch of boreholes come up short due to broken drill bits and difficulties getting through frag rock. When you've got lots of space accessible to the drill rig it's easy to just dig another hole if one goes awry or comes up short and the drill rig doesn't hold up other activity.

    From a carbon and energy perspective, ground source is hands down the way to go. I've just been burned with drilling issues.

  7. #20
    Join Date
    Apr 2012
    Location
    Georgetown Delaware
    Posts
    197
    The lion share of drilling issues are based in in-experiance. I have taken my share of lumps. When you pile up issues on one site, you are generally asking for it. We counter act nature by talking alot upfront about fall back positions and plan B's on sites where the lot size does not allow any flubb. The other side of that is that you really need to hire a looper that is local. They know when and where to expect what and how to deal with it, or punt.
    Eric

    Just to stir the money pot a bit. Vertical closed loop resi goes for 6 dollars a foot in my AO.

  8. #21
    Join Date
    Feb 2009
    Location
    Portland OR
    Posts
    2,030
    Quote Originally Posted by waterpirate View Post

    Just to stir the money pot a bit. Vertical closed loop resi goes for 6 dollars a foot in my AO.
    Come to Oregon, I would go vertical on most jobs and sell twice as much geo for that cost! Every driller here complains about our soil and rock etc and nobody can do it for less than $18 a foot. Hell charge $10 a foot and I will guarantee you will stay busy.
    Check out my YouTube channel - http://www.youtube.com/user/skyheating1 We have customer testimonials, product reviews and more!
    Like us on FACEBOOK if you like our advice here!

  9. #22
    Join Date
    Apr 2012
    Location
    Georgetown Delaware
    Posts
    197
    No thanks!
    I will stay with my sand and shale, thank you. lol
    Eric

  10. #23
    Join Date
    May 2012
    Location
    NY
    Posts
    21
    Put it on paper. The avg. install cost of a geo thermal system is 30k.(in my region) If your saving 1.8k per yr that is almost 17 years before a return on investment. (ROI...yes that means before you even begin to save a dime)
    My big concern is your heating figures seem off. Is your 700 gal figure based on the entire year or just heating season? Your numbers say....700 gal of propane x 91600 btu per gal = 64,120,000. If that is for the gal usage of the season your hourly heat loss calculates to : (64120000/352)/24 = 7589 btuh. This is unreasonably low. Even changing the number so that your 700gal bill is for just the heating season (roughly 6 mths) it still seems low. In different scenario using only 6 mth usage (1/2 of previous example) our numbers are 700 gal lp x 916000 = 64,120,000. (64120000/176) /24= 15179btuh.
    In either case it seems your ROI is very lengthy and this is not even considering maintenance, repairs, equipment failures, depreciation and inflation. In my honest opinion a geo thermal system is not your best option. (Unless of course the bids you are receiving are much more reasonable than my 30k and from reputable companies)

  11. #24
    Join Date
    Apr 2012
    Posts
    19
    It looks like $20,000 after tax credit. My savings should be about $2000 per year, including hot water and a/c. My furnace and a/c are 8 years old, so that's part of the ROI also. Yes, about 700 gallons to heat the house each year. We use propane only to heat. Blower door test shows about 7.5 air exchanges per day, or .33 per hour. 8 year old house, r-19 walls, r50 attic. Yes, so about 65 million btus.

    I'm figuring $5000 added to value of house if we sell, so now we're down to $15,000. So now break even is at 7 to 8 years, plus factor in buying new a/c @ $5000 in 8 years, and in that case I'd replace whole system with heat pump at $10,000 vs going with new a/c and staying with propane.

    Still waiting for more bids to come in, will reevaluate then.

    Working on getting a price on the altherma. Also, Carrier Greenspeed air source heat pump @ $12,000 is a possibility, (HSPF of 13), saves me $1200 per year, break even in 10 years.

    I have a pretty elaborate spreadsheet that I created showing all my options and the costs breakdown and net cash flow each year. Doing nothing and continuing to pay $3 for propane is the worst option. Only risk with geo is having to move and sell house before year 8. I have option through PA state for 10 year loan at %1 for half the cost of geo and %4 through state for rest. Payments on both loans combined should be less than my monthly savings from geo, so net positive cash flow month to month.

    Gotta do something, I told propane company I refuse to pay $3 and asked him how he sleeps at night, price gauging customers who are leasing tanks. Three neighbors had to dig their tanks up and replace with identical tanks so they could shop around. Propane company refuses to sell the tanks (underground 500 gallon tanks that we signed a lease agreement when we built at settlement). There is no cheap solution.

    Outside wood hot water boiler is probably my cheapest, smallest break even point option, but I'm not chopping wood and dealing with all that.

  12. #25
    Join Date
    May 2012
    Location
    NY
    Posts
    21
    You certainly seem to have the numbers down. Unfortunately with the price of lp in your area there aren't a lot of options. A geo system seems like a huge investment if your considering a move in the near future. Contrarily, you will invest about 16k in lp alone over the next 8 years (assuming prices don't inflate). Your in between a rock and a hard place. Either way you have a considerable amount to spend. In this scenario given your installation cost and factoring in rebates, hot water and ac; I would personally lean towards the geo system. Even if you didn't quite make it to your payback period (8-11 yrs) at that point it would be water under the bridge. You could at least say you improved the local economy and foot print on the environment. Best of luck!

  13. #26
    Join Date
    Apr 2012
    Location
    Georgetown Delaware
    Posts
    197
    You are lucky to pay 3.00 a gallon. This past heating season propane sold for in the neihborhood of 3.85 a gallon for heating.

    I am no math wiz, nor am I a economist. What I am is a guy with a lot of common sense. I hate the whole investment/Roi pitch because I understand that with enough swagging you can make 2+2=37.

    Price gougeing is rampant in geothermal due to inexperiance of both the HVAC people and the people doing the loops or othe exchanger install. Gougeing happens do to inexperiance so they add danger money or no competition in their OA, or both.

    This is how I think about the costs, understanding that any contraption used to heat and cool your home is a choice. If a traditional system costs 20k and a geo costs 30k that is a difrance of 10k additional cost. That is the amount of money we should be looking at for any math discussion. My other question about ROI is that what is the return on a conventional system? You buy it, you use it, you pay bills to run it, you fix it, when it dies you throw it away. That is a great ROI.

    Most loops are warranted for a minimum of 30 years and sometimes 50. In my mind loops will be under the fridge with the cockroaches, still working after a nuclear event.

    Geothermal is a choice and does not need to be marketed or justified, it just is.
    Eric

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