Replies

1. 
   CloudHidden | Aug 29, 2004 04:41am | #1

   It'd seem like a straightforward analysis to compare the $/mbtu/h of one versus the other. Find the rates and the btu output and your load and see what wins.

   Oh, and look into electric boilers or heat pumps, too. Water heaters require a lot of power to achieve the btu. My ground source heat pump outperforms the water heater by a factor of at least 4.

   
   

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   Edited 8/28/2004 9:44 pm ET by Cloud Hidden

1. 
   JohnT8 | Sep 01, 2004 06:25pm | #5

   Hey Cloud, how do you like that ground source heat pump? 

   I have been considering one, but haven't made up my mind if I want to spend the extra $$.  If I did have one installed, I'd probably opt for the vertical loop (call the well driller), thereby limiting the amount of yard I need to protect from trenchers, tree roots, and the like.

   Around here it gets hot/humid in the summer (up to 100 F with 90+ humidity) and cold in the winter (typically around zero F, but occasionally substantially lower).   Do you see any problem with a ground source being able to keep a 2k sq ft (well insulated) home at 72 year round?

   If I stay with the same utility, I'm only paying 6 cents/kw.  I like the thought of stable electric rates better than the wildly fluctuating natural gas.

   jt8

1. 
   CloudHidden | Sep 01, 2004 07:04pm | #6

   I think all the reasons you gave are in its favor, though only you can decide if the cost works out for you. I like the quiet operation and the stable elec rates. I'm heating/cooling 6000 sf w/ a 4 ton unit and an 805' deep loop.....2k sq ft should be a non-issue. I didn't have room for a fuel tank, nor the desire for one. This was a good solution for me.

1. 
   JohnT8 | Sep 01, 2004 09:16pm | #8

   Cloud, looks like the GSHP is right up your alley.  They probably work well with those domes.  You're located where, NC?  Probably just as muggy down there (or worse), so I would assume the cooling/dehumidification portion must work.   In a structure of that size, are you employing one 4 ton unit, or do you make use of multiple smaller units?  Are you running a forced air system and a radiant floor?

   I'm planning on playing GC on this house.  It is likely that after I'm in it for a few years, I will sell it and build another, so I'm a little hesitant in putting in all the bells & whistles that I would like to (especially if they wouldn't increase the sale price).

   From a financial point of view, I might be in the house long enough to pay for the difference in price between the GSHP and a regular system, but I won't be in the house long enough to pay for the whole system.  So I guess my gut reaction at this time would be to include the GSHP (if it works as advertised) but hold off on the radiant flooring until the next house. 

   jt8

1. 
   CloudHidden | Sep 01, 2004 10:46pm | #9

   Yeah, NC. I've found they work well wherever the temps don't have to be too high. It's speced at 4 ton, but performing about 5 based on our measurements, so I'd say it's working well. We only have one unit, and a 3 ton Unico air handler. The unico's for A/C, and rfh as you mentioned. Plus a dehumidifier, since the a/c doesn't run much.

2. 
   dIrishInMe | Sep 08, 2004 03:14am | #11

   In the original post, the guy was concerned about the $670 CD (not sure how much that is in US), and referred to it as "large coin".  What was the cost of your ground source heap pump setup (including the excavation, etc))? 

   Matt

   Edited 9/7/2004 11:08 pm ET by DIRISHINME

3. 
   CloudHidden | Sep 08, 2004 06:47am | #12

   Too much. But that's not the only kind of heat pump, either. That's why he needs the economic analysis. Replacing what I have with elec water heaters woulda saved me thousands in installation, but cost me maybe a grand a year in extra heating costs. There's a payback in there somewhere. Should someone else do it? Dunno. All I suggest someone else do is calc the cost of the alternatives.

2. 
   vivadriver | Aug 29, 2004 07:32am | #2

   Depending on the area of  beautiful Georgian Bay you are at I'm not too far from you and know how long and cold the winters are. However a guy on my hockey team did some radiant floor heat in his house on the shore of beautiful Windy Lake.  Long story short, after two winters the hot water tank got yanked and in went a Victory Boiler. That was for his whole basement though. Check out all the options.

   Have a good day...Vivadriver

1. 
   MrBlister | Aug 29, 2004 05:30pm | #3

   Thankx for the input.  This addition is insulated within an inch of it's life.  The basement is built with Arxx ICF.s.  The basement RFH is on 2" of foam, and then 3" of concrete and the main floor has a 2" concrete screed to imbed the RFH.  The finish floor will be Mexican Saltillo Tile.  (lots of thermal mass.) The main floor walls of the addition are 3" polyurethane foam, and the cieling is R40 celulose fiber.  There should be lots of thermal mass to hold the heat.

1. 
   CloudHidden | Aug 29, 2004 06:07pm | #4

   I have a million pounds of thermal mass (literally) and 3" of continuous spray polyurethane foam everywhere, but it still comes down to calculating loads, knowing btu requirements, and doing the math of what will provide them at the best cost.

3. 
   whoover | Sep 01, 2004 08:00pm | #7

   If you are a typical water heater user, you will find that the annual operating cost for the elec tric is about three times that for natural gas.   Even though you are paying a ridiculous amount for the w/h, I would guess that you would save the $500 cost difference in a few years.

   Bill

4. 
   TRice | Sep 07, 2004 08:41pm | #10

   "Not sure about the cost of kilowatt hour of Hydro, ........ am I missing something?"

   The cost of electricity is what your missing. Electricity (resistance heat), at all but the lowest rates, is more expensiveto heat with than fossil fuels. There are no absolutes, though.

   Electric resistance heating devices are very easy and cheap to install. That is why the elect WH is alot cheaper than a gas fired version. No piping, venting, gas valves and controls.

5. 
   csnow | Sep 08, 2004 09:00pm | #13

   Yeah, in New England the electric runs roughly 3x the cost of gas.  Payback is pretty quick.

   Perhaps your electricity is cheap.  Electric units are cheaper buy and install, require less maintenance, and last longer, so balance that in.