Looking for some feedback here. 
I am getting bids on a new house and here is where we sit: Location is NE Iowa.

Efficient construction with staggered studs on 2x8 sill plates, caulked and foamed. 1.5" XPS exterior sheathing, caulked and taped. dense packed cellulose in the walls, roughly r-35.  Ceilings is r-60. Windows are fiberglass with a u.=28 House is a single story with walk out basement.  Basement walls are ICF except on north face, where it is same frame construction as above.  Main level is 1550 sqft, lower is 1550 sqft w/ 2" XPS below slab, infloor radiant heat (optional).  A very conservative amount of glass being used.

Geo specs and included in price:  3 ton, 2 stage waterfurnace Syn. 3. w/ horizontal fields.  Desuperheater w/ buffer tank for infloor heat. infloor install (not the full 1550 sqft, rather about 600sqft of that) ERV, all duct work.  $35k
They have not done a heat load calc on this, they know they need too.  He thought if we did not do the infloor heat (I am not sure I see a point bc of carpet and pad in the basement) then it would be reduced to a 2 ton, 2 stage, possibly around a 4k savings. 

This same company installed my current HE Lennox gas funace in my house I live in right now.  They had the best prices of all bids.

Other people I have talked to are estimating more around 25-28k. 

They have also supplied another option of an all electric Lennox 2 ton 16EER HP w/ electric 2 stage air handler and backup heat.  ERV, all duct work, 12,500. 

We are also looking at an air handler w/ electric resistance.

The only gas option would be an LP tank.  Electric rates are currently $0.103, but drop to .04 in the winter after first 600KW is used.  On the flip side they jump to .19 in the summer after the first 600kw. 

I am attempting to decide if 7k+ (after fed rebate) will pay for itself or not.  I am thinking it will have a long payback period with this type of construction.  Anyone have a good website where I can input costs and compare that way and figure out pay back?

thoughts on the purposed systems or concepts? (I will also get other quotes from Trane, Currier, etc)

I don't accept that giving up infloor heat somehow reduces whole house load. The house needs what it needs.

4 cent winter power is incredibly cheap...given that I'd be quite tempted to go with the best air source heat pump system proposed and eat the costs of operating strip heat as needed.

The Lennox bid (or similar by Trane and Carrier dealers) may in fact be the best choice. Are you absolutely certain of 4 cent kWhrs for consumption above 600 / month?

Geo would give you some summer savings, but given the modest size of the house I doubt the difference between geo and a high end air source heat pump would be more than $100 / month, probably less.

yes, possitive on .04.  However it is not for everyone.  It only applies to people who build to a performance standard they set (similar to energy star) as well as uses all electric for their needs.
They also offer rebates for geo and air hp installs, although it is not very much. 

The 3 ton reducing to 2 ton also does not make sense to me.  It is my understanding that the house will use what it needs, and a desuperheater is added for the water collection w/ buffer tank.  I did not know you needed to add another ton for this...espeically to only heat 600 sqft of floor.......

Am I understanding you correctly in that two of the choices you have are a 3 ton Geo heat pump (+ some radiant) for $35K and a two ton Air Source HP for $12,500?

In other words, if you kick out $2,500 for the radiant heat, the difference is $20,000 between the two?

infloor was not included with the 12500 number, that added another 3k for pex install, boiler, tank, etc.  But if you take out the infloor completely, you are looking at 31k vs 12500, so around 18,500 difference.  If you want to be technical, wach 30% off of that, and it cuts it down to 21700, so a 9200 difference.  However the other system gets about 1200 in rebates, so you are back up to 10,400 difference.

I think that is a good analysis for feasibility, but what are you getting for the initial $18,500 difference? The difference in cost of hardware between the two systems is what.....$5,000 at the outside? What is the remaining $13,500 going towards?

With an accurate manual J, your heating and cooling costs can be estimated by the installer with both systems (include DHW production cost as well.) On a basic level (you can factor in interest if you want), the $10,400 difference divided by the annual geo savings is the number of years until the geo system pays back the incremental cost between the two systems. You need to see if it is worth it to you.

You could lower the pay back period by going with one of the lower cost installers, but check all references. Remember, if your loops can be reused at the end of the useful life of the current geo system, you won't have that expense again when replacing the system.

Posted By geome on 19 Jan 2011 10:21 AM
With an accurate manual J, your heating and cooling costs can be estimated by the installer with both systems (include DHW production cost as well.) On a basic level (you can factor in interest if you want), the $10,400 difference divided by the annual geo savings is the number of years until the geo system pays back the incremental cost between the two systems. You need to see if it is worth it to you.

You could lower the pay back period by going with one of the lower cost installers, but check all references. Remember, if your loops can be reused at the end of the useful life of the current geo system, you won't have that expense again when replacing the system.

well you will also have the loops in there, which around here, a vertical loop costs about 2k installed.  assuming they would need 2 or 3, thats only another 4-6k.  So your question is exactly my question.  What is the difference in cost for?  From me research, in my area, this shouldnt cost any more then 25k.  I could be wrong obviously.

The one thing is he has not done the calcs yet, but will he claims obviously.  These were "budget numbers only...but should be pretty close assuming the sizing close" was what he told me.

I was going under the assumption that the "w/ horizontal fields" were included in your quotes. Horizontal loops work fine if sized and installed correctly (vertical loops need to be sized and installed correctly as well.)

To tell the difference in cost, you need to get firm quotes, and possibly more quotes if you are not happy with them (not much else you can do unless you want to do all or part of the job yourself.) The only questionable part of our quote was the loop, that is, if there was an insurmountable digging problem with a horizontal loop, we would need to have gone vertical at additional expense.

Some installers charge for a manual J, and some do not. If you want good quotes, you may need to get the manual J calculation done. I would suggest getting more than one done to make sure they agree (since errors can be made.) Or you can try to do one yourself with a program such as HVAC-Calc for a temporary license of about $49.

I plan on getting 3-4 geo quotes and more "standard" quotes.  All are required to itemize and supply J calcs.  All have said they will do it with their quote. 

He included horizontal in the price.  I mentioned vertical because ultimately, I think that is what we would do for space reasons.  The lot is almost 1 acre, but on that acre we also need a septic system, so that eats up a lot of space as well. 

Posted By lzerarc on 19 Jan 2011 12:24 AM
yes, possitive on .04.  However it is not for everyone.  It only applies to people who build to a performance standard they set (similar to energy star) as well as uses all electric for their needs.
They also offer rebates for geo and air hp installs, although it is not very much. 

The 3 ton reducing to 2 ton also does not make sense to me.  It is my understanding that the house will use what it needs, and a desuperheater is added for the water collection w/ buffer tank.  I did not know you needed to add another ton for this...espeically to only heat 600 sqft of floor.......

Sure, the house needs what the house needs, but the geo can run without backup heat down to temps much lower than the air-source heat pump.  A good designer would rate the size of the compressor for the heat load at the outdoor temps where it's COP is low enough that the resistant  heating would be necessary.  Putting in a 3 ton air-source heat pump wouldn't reduce the annual operating cost much (if at all.)  A 2-ton heat pump would be much more appropriate for your cooling loads too.

On projects like this it's good to take a step back and consider whether a PassiveHouse approach on the building envelope (taking it way beyond EnergyStar) and skipping the cost of heating system entirely might be ultimately the better deal.  (It probably is, if geo is the heating option. With an air-source heat pump solution, maybe not.)

Is anybody supporting cold-climate air-source-hydronic heat pumps in your area?  The  Daikin Altherma still puts out ~18-19KBTU/hr @ +5F (with a COP of 2.4, with defrost-cycle derating included), or 16-17KBTU/hr @-4F  (which is probably close to your design temp.)  NRT.Rob (who posts on the radiant forum here) has been running one at their office in Maine (at similar design temps), hasn't measured it's performance, but seems impressed overall.  That (and possibly some supplemental resistance heating for peak loads)  might be an intermediate soloution.  At 25F the thing puts out ~24K, with a COP north of 3.

"Other people I have talked to are estimating more around 25-28k."
The price difference you want to reconcile is the one between 35K and the "other peoples" 25-28K.
That's an awfully large disparity for apples to apples geo.

At 4 cents a kwh electric baseboards could heat the house for $2,500 installed! I'm with Curt, you really wanna make sure the dollars make sense here.
Joe

well I have been doing some energy modeling in Revit and loaded my model into Autodesk Green Building Studio to check out the results.  Obviously my heating load will be dominate in my climate, but a 2 ton unit is still pushing being over sized for the cooling load.  Heating load would be about the right sized, but a 8-10kw heat strip added for peak nights (suppose to be -30 tonight with wind chill for example).

However running numbers, it does not appear pay off will even be done before the mortgage is paid.  I have to doubt we will even be in this house for 30 years anyway.  I can see us building another one, who knows though. I do have the design setup so it  can easily be added onto if we need more bedrooms for example.

So this leads me back to other options, sized at 2 tons or less.  Dana, I have heard and did some research on the Daikin stuff.  There are no installers within 50 miles of me, and that was the furthest their website would allow me to branch out.  Not sure if I would want to go down that road if there are problems in the future.

So really from what I can see, I have 2 options.  Standard AC and electric furnace vs heat pump and air handler plus aux heat strip.  Either would have some sort of high end filter and ERV. Possibly a dehumidifier and humidifier.  I am thinking a dehumidifier might be more efficient in the summer then the HP running.  Our temps do not get overly hot on average (typically stays in the 80s, sometimes 90s) but humidity is always 70-80% and higher.

I have also have a bonus room over the garage that will someday be finished, but for now probably just a large storage room.  Getting duct work up there might be slightly tricky.  I have considering putting one of those small single units from Mitsubishi or something up there instead when we do finish it out.  Any thoughts?

Humidifiers aren't necessary in a tight house in your climate- humidity can be maintained at 30-35% simply by backing off on the ventilation rate. An ERV/HRV under dehumidistat control would be sufficient, in winter.

Look for heat pumps with a dehumidfication mode rather than going with a separate system in summer. In dehumidification mode the blower speed is backed off to minimum, which handles the latent load more effectively/efficiently than the sensible load. But if the unit is oversized for the cooling load by 2x, a room-dehumidifier can often handle the whole-house latent loads in a tight house if the ventilation rate is reasonably low. (Going with an ERV vs. HRV helps too.) Mini-splits may be an option here too.

The outdoor relative humidity is the most-reported number, but the least relevant from an AC point of view, because it's relative (to the outdoor temp, which is variable). The absolute humidity that determines the latent load of the ventilation air is the outdoor dew-point. An outdoor humidity of 75% when it's 75F out isn't NEARLY the load of 75% relative humidity @ 85F. The former has a somewhat muggy but tolerable 67F dew point, but the latter has a stifling torrid 76F dew point.

here is the all electric option I have gotten so far.  He will also supply me with a 2 ton 2 stage geo quote, he says it should be "sygnificantly less"....

Lennox CBX27UH-024 blower coil w/ electric heat strip
XP16-024 2 ton 16.5 SEER HP.
HRV, auto switch over thermostat, all ducting and load calcs- $12,120

adds would be 2 ton 19 SERR HP- 850
CBX32MV-024 blower coil- 550
CBX40HV-024 Blower Coil- 700

THoughts on something like this?  Does anyone know how you calculate the efficiency and opporating costs of this in my area? (elec is .10 standard, after 600k in winter it drops to .04, after 600 in summer it jumps to .16 or.19, something like that.)

I have heard and did some research on the Daikin stuff. There are no installers within 50 miles of me, and that was the furthest their website would allow me to branch out. Not sure if I would want to go down that road if there are problems in the future.

If you ask around the quality outfits, you might find one who wants to get set up with Daikin. When I first started looking, you had to call long distance to find one and there were very few installed units, but since then, I've found local outfits who will get trained and set up in preparation for the first job.

And, doesn't Hallowell have one with the "Acadia", too?

Acadia's reviews have been less than stellar.
If your deep winter temps are near 30* I think ASHP may make sense to you. With electric rates, gas probably doesn't. With the summer rates as they are high seer ratings make sense as well.
There are comfort and warranty issues at stake here too (higher end equipment generally has longer warranties).
If humidity will need to be controlled in the summer that's when you'll be greatful for high end heat pump.
Do not assume lower end (cheaper equipment) offers the same comfort. Sure a Chevette will get you to work just like a Caddy, but one is a heck of a lot more comfortable.

If you are still looking at geo, the 35k bid seems out of sight and remains unreconciled, by your description. I suspect it is the only one that includes in floor piping, water to water heat pump, additional buffer and controls etc.
By continuing to not offer us detail you cripple us in our ability to help you digest the bids.
j

we are below 30 for at least 2-3 months out of the year.  THe electric aux stip in the air handler would be the main heater during that time, which is what I am concerned about.  However with it dropping to .04 during the winter, maybe it would be bad at all.

Unfortunately, what I posted is ALL I have at the moment.  It was a "budget" number, but I requested breakouts. 
Yes, 35k includes basically everything possible...3 ton, 2 stage Waterfurnace, dehuperheater and tank, infloor install, hrv, horizontal loops, etc.  He is suppose to be giving me the 2 ton 2 stage option.  I also have 3 other companies working on their estimates so hopefully I will have something to post and compare too.

we are below 30 for at least 2-3 months out of the year. THe electric aux stip in the air handler would be the main heater during that time, which is what I am concerned about.

The new air source heat pumps that have been thrown around still deliver a COP of just about 3.0 at freezing and 2.0+ all the way down to 0F. However, the heat output is about 70% of rated output at freezing and about half down at 0F. If the system is sized to meet needs at only at higher temperatures, then you will have Aux strips kicking on at a COP of 1.0.

So, you can oversize the system, which, because of inverter technology might not be as bad as in the past when oversized units short cycled.

OR, you do a combination of the both - oversize it a little and then just put up with the lower efficiency of the electric heat strip during the coldest periods.

An ideal situation is if you can have backup heat to cover those extra cold periods. For us that is a wood fire in an efficient fireplace. The fire goes on in late afternoon, is burned into the evening and then stoked for an overnight burn. It puts out enough heat during the coldest overnight periods to make up for what the heat pump can't deliver. Allows us to go with a single undersized heat pump which covers us for most of the year.

Posted By ICFHybrid on 22 Jan 2011 03:08 PM

The new air source heat pumps that have been thrown around still deliver a COP of just about 3.0 at freezing and 2.0+ all the way down to 0F.

Including defrost cycles?