I am considering geothermal for my home here in west central NJ. I presently have multi-zone hydronic heat. I heat my house, detached garage (to 50 degrees), hot water, and cook using about $10K in propane per year. I have been hoping to achieve two goals here... Significantly reduce my energy costs as well as improve the value of my home by making it more energy efficient. In reading through the posts on this website, I'm beginning to question just how much the savings might be. It would appear that the picture is a bit less rosy than most commercial websites paint. I don't expect a quick payback. I'm more concerned with the overall cost of energy in my home and how it would effect my ability to sell our home in the future.

I'd like to get someone who knows what they are doing to come in and tell me what I could realistically hope to achieve and what it would cost to do it. Can anyone recommend a reputable firm in this area (Flemington,NJ)?

We would need to know how many btu's needed to be replaced (manJ load) as well as kwh cost, to hope to answer your question.

That's a lotta propane!

Unless the house is 10,000 square feet, I suspect the low hanging fruit lies in tightening up the building envelope rather than sizing a geo system to replace whatever burns that much propane.

Call Gary Brill and Pam at Millpond Mechanical sales in Port Republic. They have contacts state wide in regard to competant installers.
Eric

If you want to take advantage of the incentives the State of New jersey is offering, you must used one of the state approved contractors.

http://www.njcleanenergy.com/residential/tools-and-resources/tradeally/approved_vendorsearch&start=

What engineer said- don't even THINK about sinking $25K + into a heating system until you calculate what a similar amount (or large fraction thereof) spent on envelope improvements would buy you. Such as...

Air-sealing the place to less than 2 air changes per hour at 50 pascals (ACH/50) may only cost a few grand and could be a huge reduction in both peak & average loads.

Spot-insulating where it's cheap & easy to beef it up can be similarly cost effective and load reducing. Is your band joist & foundation sill foam-insulated? How about the foundation walls?

Are there any single-pane glass in this place without decently tight exterior storm windows?

Every ton of geo costs, and improving the envelope to remove another ton of load often costs less.

With NJ's outdoor design condition temps if you can get your design-day heat load down to something like 35KBTU/hr you can probably run a Daikin Altherma air-source to hydronic heat pump with geo-type annual performance, yet a simpler (and likely cheaper) system design & installation. It'll be more than half the cost of geo per ton, but not 3/4 as much. If your radiation is currently designed or condensing propane you can do VERY well with one of these. If it isn't, the cost of adding sufficient radiation to get another 0.5 in COP out of it may still be less than the cost of geo (and would probably be necessary to get the performance out of the geo running the same radiation anyway.) See:

http://thermalproductsinc.com/wp-content/uploads/2010/06/Daikin-Altherma-Engineering-Data1.pdf (see the capacity tables starting on P20 for the pump performance at different outside temps.)

It's easy to get enamored of a particular technology or solution, and there are many ways to skin the efficiency cat.

Getting a rough handle on it, Flemington's climate is ~5800 annual heating degree days (see: http://climate.rutgers.edu/stateclim_v1/norms/monthly/hdd.html ), and the design temp is around +10F. Assuming that $10K/year of propane is at an average price of $3.50/gal delivered you're looking at ~2800 gallons a year, which has a source energy content of ~255MBTU. Burned in 90% condensing boiler that implies a thermal load of ~225MBTU/year. Assuming 1/4 of that it hot water (typical for 4 person household in the NE), it means the space heating load is ~169MBTU/year. Dividing by 5800 heating degree days, that's ~29000BTUs/hdd, or /24 hours/day becomes ~1200BTU degree-hour.

A design temp of 10F that's 55F (base-65, less 10F degrees), so your peak heat loads would be roughly 55x 1200= 66KBTU/hr/

If your boiler is an oversized cast-iron beastie running 80% efficiency your peak heat load is really more like 58-60K.

Which is literally about twice my design-day heat load in ~3500' of conditioned basement + living space in central MA with a design temp of 0F, in a sub-code antique of a house (but I'm working on it, a bit at a time...) Unless yours is a real palace I'd be shocked if you couldn't cut the load by at least a third for $10-15K (maybe less after subsidies) in well targeted air sealing and insulation improvements.

Once you're below 50KBTU/hr loads Althermas start to make sense, but you'd still be running auxilliary heat quite a bit during peak periods, and annual COPs wouldn't be as good as geo, but operating costs would likely be well under that of propane. At 35KBTU/hr (peak) and under you could do VERY well with an Altherma in NJ.

Is fixing the envelope and going that route cheaper than going with 6 tons of geo to support the current load? Would the 6 tons of geo be cheaper to operate? Get some numbers, sharpen your pencil, but very often you can buy more in envelope efficiency reducing the load than it would take for the extra ton or three of geo, and when that's true the higher efficiency building envelope is usually the better investment.

A little more information... My house is around 4000 sq. ft. The portion of the garage that I heat to 50 degrees is another 1500 sq. ft. My biggest problem in the house undoubtedly is a sun room on the second floor that is floor to ceiling glass, along with several large skylights. You can feel the cold air dropping down the steps from the second floor. Not much that I can do about it without a major rebuild of the house. Other than that, the house is built pretty tight. Pella windows all the way around. The house is quiet and well insulated.I don't think that there is too much that can be done to tighten things up.

Posted By JerseyJim on 07 Mar 2011 06:27 PM
A little more information... My house is around 4000 sq. ft. The portion of the garage that I heat to 50 degrees is another 1500 sq. ft. My biggest problem in the house undoubtedly is a sun room on the second floor that is floor to ceiling glass, along with several large skylights. You can feel the cold air dropping down the steps from the second floor. Not much that I can do about it without a major rebuild of the house. Other than that, the house is built pretty tight. Pella windows all the way around. The house is quiet and well insulated.I don't think that there is too much that can be done to tighten things up.

Cold air dropping down and pretty tight do not belong in the same paragraph in my opinion.  I always thought windows added heat into a house, not take it away. Have you considering adding insulated skylight coverings?

[quote]
Posted By TechGromit on 07 Mar 2011 10:12 PM
[quote]
Posted By JerseyJim on 07 Mar 2011 06:27 PM


A little more information... My house is around 4000 sq. ft. The portion of the garage that I heat to 50 degrees is another 1500 sq. ft. My biggest problem in the house undoubtedly is a sun room on the second floor that is floor to ceiling glass, along with several large skylights. You can feel the cold air dropping down the steps from the second floor. Not much that I can do about it without a major rebuild of the house. Other than that, the house is built pretty tight. Pella windows all the way around. The house is quiet and well insulated.I don't think that there is too much that can be done to tighten things up.
[/quote]
Cold air dropping down and pretty tight do not belong in the same paragraph in my opinion.  I always thought windows added heat into a house, not take it away. Have you considering adding insulated skylight coverings?


[/quote]

Actually the issue is convection. Hot air expands and rises to the second floor. Denser, cooler air sinks to the first floor. The greater the differential, the stronger and more notable the flow. Not much I can do about. The glass is double pane with substantial spacing. There's just a lot of it. On sunny days, it heats a dark tile floor and a large stone chimney. So there is some minor benefit there. This home design is simply inefficient. So it really boils down to trying to produce heat at a lower cost.

Posted By JerseyJim on 07 Mar 2011 06:27 PM
You can feel the cold air dropping down the steps from the second floor. Not much that I can do about it without a major rebuild of the house.

Is there a door to this room that can be closed?  Keeping our upstairs doors closed (and putting a remote thermostat sensor in one of the bedrooms) has made a dramatic improvement in our house.

Posted By geome on 08 Mar 2011 07:43 AM

Posted By JerseyJim on 07 Mar 2011 06:27 PM
You can feel the cold air dropping down the steps from the second floor. Not much that I can do about it without a major rebuild of the house.

Is there a door to this room that can be closed?  Keeping our upstairs doors closed (and putting a remote thermostat sensor in one of the bedrooms) has made a dramatic improvement in our house.

Our house has a entry foyer that is open all the way to the 2nd story roof (cathedral ceiling in this area). The sun room is open to and directly behind this foyer. It is about 20 feet wide and open completely to the first floor. Beautiful...But totally inefficient design from a heating and cooling standpoint. No way to block this area off.

Jim,
First off, it sounds like geothermal might be a good fit. Now the questions. Help us help you.
What are your costs per kwh for electricity?
What are you paying per gallon for propane, high low and average
How much propane storage capacity do you have?
Do you own your own tank?
How much room do you have in the yard for a large tank?
What type, output and efficiency is your current propane boiler?
Hot water from an indirect tank or other?
Is natural gas available?
If I was paying 10K per year to heat my house, my first step would be a very careful energy audit. Clearly a wall of glass is not helping your case, but there may be other issues you are overlooking. Any builder who prioritizes looks probably skipped a few other things.
Propane costs also vary widely. Are you sure you are getting it at a reasonable price?

Cheers,
Eric

Jim,

The data requested will be valuable to make a very accurate cost calculation. You mentioned how much liquid energy in dollars you're using, but not year built. This gives us further data to work with. You should pursue geothermal because we haven't seen a home using propane that didn't benefit big time from installing a geothermal system. The cost to generate a million BTU's using propane and a million from geothermal is night and day. Propane costs more than three times as much (with kWh @ 15 cents) to generate the same number of BTU's.

Tightening up the thermal envelope is the first order of business. After that a geo system will work for you. Good luck

Paul
Total Green Geothermal
www.TotalGreenUS.com

Posted By TechGromit on 07 Mar 2011 10:12 PM

Posted By JerseyJim on 07 Mar 2011 06:27 PM
A little more information... My house is around 4000 sq. ft. The portion of the garage that I heat to 50 degrees is another 1500 sq. ft. My biggest problem in the house undoubtedly is a sun room on the second floor that is floor to ceiling glass, along with several large skylights. You can feel the cold air dropping down the steps from the second floor. Not much that I can do about it without a major rebuild of the house. Other than that, the house is built pretty tight. Pella windows all the way around. The house is quiet and well insulated.I don't think that there is too much that can be done to tighten things up.

Cold air dropping down and pretty tight do not belong in the same paragraph in my opinion.  I always thought windows added heat into a house, not take it away. Have you considering adding insulated skylight coverings?

So in New England we should all be maximizing the glazed area, cutting back on insulated walls?

In NJ south facing double-pane glass results in an annualized net gain in heat (and even reduced heating bills somewhat in modestly insulated houses) but not at night, which is when peak heating loads occur.  After sundown when it's cold out it represents a signficant heat loss- every square foot of glazing is an R2-R3 hole in your ~R10 (if 2x4) to R14 (if 2x6), assuming it's a typical fiber-insulated stick built structure.

The interior temp of the glass will be well below room temp, enough to drive strong convection current making it feel pretty drafty, even if tight.

I live on Long Island. I recently went through a similar exercise. Although my home is only 2200 SF, the thought process is the same - The cost to install geothermal was 50 to 55K. Even though I have an 8.1 KW solar installation on my roof to help pay for electric to run a geothermal system, i did my homework and found it way cheaper to install a high efficiency natural gas system. Look at the overall cost. True, geothermal is really neat, but it does use electric and it does cost a lot to install. Here on LI we pay $0.215 per KWH. My solar panels would work almost full time just to cover the electric the geo system would consume (on an annual basis). The cost of the system and the electric I would have to purchase just didn't justify geothermal. In the end the 95% efficient gas system was clearly the way to go.

Posted By jim5821 on 14 Oct 2011 11:37 AM
I live on Long Island. I recently went through a similar exercise. Although my home is only 2200 SF, the thought process is the same - The cost to install geothermal was 50 to 55K. Even though I have an 8.1 KW solar installation on my roof to help pay for electric to run a geothermal system, i did my homework and found it way cheaper to install a high efficiency natural gas system. Look at the overall cost. True, geothermal is really neat, but it does use electric and it does cost a lot to install. Here on LI we pay $0.215 per KWH. My solar panels would work almost full time just to cover the electric the geo system would consume (on an annual basis). The cost of the system and the electric I would have to purchase just didn't justify geothermal. In the end the 95% efficient gas system was clearly the way to go.

$0.215 per KWH for electric!!! In Portland we pay $0.108 per KWH and some of the PUD's in the area pay half that. It sounds like NG may be better in your area but not all areas. How much are you paying for NG? We are about $1.20 per therm.

Even at 21.5cent/kwh geo with a system runnng average COP (pumping power included) of 3.0 would be dramatically cheaper than oil, but well over the operating costs of condensing-gas:

Consider, 1 therm of gas in a 95% system delivers 95,000BTU to the house.

1kwh x 3412BTU/kwh x 3 = 10,236 BTUs delivered to the house for 21.5 cents so it would take 95K/10.236K= 9.3kwh to deliver the same heat to the house as 1 therm. From an operating cost point of view it's about the same as $0.215x 9.3= $2/therm gas,(which is quite an upcharge to pay extra for up front, eh?) The efficiencies at which geo at 21.5 cent electricity would break-even on operating cost with condensing gas is well over what's actually attainable.

But oil in an 86% burner delivers 138,000 x .86= 118,680BTUs to the house, or 118.9K/10.236=11.6kwh worth. The oil-price equivalent of geo would then be($0.215x 11.6=) $2.50/gallon oil, quite a bit less than the average price over the last 5 years.

In fact cheap mini-split air source heat pumps (average heating COP of ~2.5 ish in that climate) can make a lot of sense for those off the gas-grid even on Long Island, even if they're not big enough to carry the design-condition load and some propane or oil is still used.

I was engaged to remotely consult a Long Island new home builder as to merits of various geo system proposals, all north of $100k. Once I figured out he had NG and the unit costs both NG and electricity really were (vs the fictional unit costs used to justify various geo options), I talked him out of geo. I further persuaded him to spend some of the savings on upgrading to foam insulation, dramatically reducing the loads.

It definitely pays to do the math, and not get too enamored with any one solution. The GEO=CHEAP OPERATING COST isn't always true, and even when true doesn't mean it's the most cost-effective of cheapest option. With all subsidies removed, photovolaics & mini-splits can often beat geo on all counts, but rare is the house where more insulation than code-min isn't the right starting point.

Agreed