I would encourage you to
look towards a hybrid solution since you have hydronic baseboard emitters,
force air and access to natural gas. Geothermal might be a good fit as well.

Look for a geothermal contractor
that is up on the latest in hydronic heating and cooling. See link below. Search
for a Certified Geoexchange Designer, as your situation is larger and more
complex than most.

You did not mention the type
of baseboard rads (cast iron or copper tube with aluminum plates) or your
electrical rate per kW.

I would be suspicious of a contractor that only wants to do one thing, such as geothermal with forced air. The best results may come from a 'blend' of technologies. This however requires more expertise and experience.

IMPO

SR

International Ground Source Heat Pump Association

Thanks very much. That
looks like a solid resource for finding more Geothermal expertise.

I think I misspoke – I think I actually have a hybrid system
– baseboard heating (copper with aluminum fins) in basement, plus a peerless
gas boiler that pumps hot water to the air handlers and Goodman condensers that
pump something to the air handlers. Here
are the models of these units:

Goodman GSC 130301EB 2.5 ton condenser

Goodman GSC 130481BB 4 ton condenser

Goodman SSX 160591AA 3 condenser

Peerless gas boiler 85-280-WPC-HD – ratings 197000 BTU/HR
Water

The condensers are all less than 5 years old. The guy who did the survey when we bought the
house said the boiler is in good shape, but somewhat old and less efficient
than what is available today.

Here are the costs of electricity and gas per my Con Ed
bill.

Electricity

Supply Charge 8.8096 cents/kWh

Deliver Charge 11.399 cents/kWh

Gas

Supply 41.4129 cents/therm

Delivery 62.6201 cents/therm

One more question – is there a recommended resource/book to
help a homeowner educate themselves on some of the core principles and
terminology, or maybe how to approach undertaking a retool of a house’s HVAC /
insulation system? I’ve had one firm
make a very expensive proposal to do a comprehensive analysis ($2,500), but I’d
kind of like to try and understand it all better myself, and be more involved
in the thought process, rather than a total outsource. And of course keep costs under control

Thanks again for any help!

I would turn the thermostats up to 80 to the units that supply non bedrooms upon retirement for the evening in the summer. A fireplace insert will heat everything up in the winter, but it's work to keep it going. A regular fireplace looks nice, but doesn't heat much. I'm assuming you have one. Check out youtube for education on hvac and insulation as there are many excellent quality productions to watch. If the solar panels weren't so ugly, they would be an option.

“Is there a recommended
resource/book to help a homeowner educate themselves?”

While I’m sure there are
many at your favorite bookstore, one book I did enjoy is, ‘Natural Home Heating’
by Greg Pahl. It’s a few years old now but I believe it’s still relevant and
interesting.

IMO

SR

You stated you spend $1100 a month with some months as high as $1500. That's about $15,000 in annual energy costs. Any idea how much goes towards heating and cooling? Even if it were half, that is a very high energy cost and you are uncomfortable. You have some serious energy issues that need to be addressed.

The house is 5000 sq. feet. Does that area include the basement? What size are the first and second floors? Is the basement mostly underground?

You have 9.5 tons of cooling capacity and 197K BTU boiler. It is hard to believe you need all that cooling and heating capacity. I think a lot of energy is being wasted.

I assume by geothermal you mean a ground source heat pump. If you didn't have natural gas then a heat pump would be a viable option. Using the the electricity and gas costs your provide I get the following estimates:

cost of 100,000K BTU of heating:

boiler @ 80% efficiency: $13.00

GS heat pump @ COP = 4.5: $13.02

The heating costs are about the same. If the boiler was more efficient then the costs would be lower. The COP for the heat pump may be higher, but probably not by much. The heat pump may help lower domestic hot water costs, but that number is small compared to heating.

You would save on cooling costs. The problem is you have 3 condensers. It is going to be very expensive to replace those. The terrain in Westchester can be diffult. Installing a ground loop could be expensive. Get some estimates but be prepared for sticker shock.

Your money is going up in smoke literally (in the winter).

Thanks for the feedback and perspective. It’s very valuable to me. Yes, the house is an energy hog. I’m trying to figure out an aggressive but
realistic plan to get it under control.
A combination of ‘blocking and tackling’ on the house envelope and
making sure the systems are performing properly, combined with an eyes-wide-open
assessment of a bigger solution like geothermal/ground source heat pump. If there is more I can be doing, feel free to advise.

We bought last year - the house was listed as 5,700 square
feet – that is including the finished half of the basement (the rest is the
crawl space). That said, the energy audit listed the house as Total Floor Area
of 12,080 sq ft, and the Total Heated Floor area as 8,900 sq ft. I’m not putting a tremendous amount of
credence in the audit (performed quickly, lots of other errors in report).

The finished basement and unfinished crawl space are mostly above
ground. The Feb energy bill consisted
of $530 elec; $620 gas (and we weren't over-heating - there were many nights the kids rooms didn't get above 60 degrees). The Sept bill
was $1,074 elec; $175 gas. The May bill
was a victory – I got it down to $232 elec; $151 gas. That was a month where there was very little
HVAC usage.

This could all be a moot point if the house doesn’t perform
better this winter because my freezing wife will throw me out and I will be
living in a shack.

I would advise that you
treat your home as if it were a small commercial/institutional project and as
such hire a professional mechanical engineering firm that specializes in
geothermal HVAC. Hire a company with serious professional credentials and proven expertise.

I still think a hybrid
system incorporating geothermal; gas and hydronics might be the way to go. By
using hydronics, small pumps can move water around carrying a lot of energy
verses having to run several much higher wattage blower motors for forced air. A
given volume of water can absorb about 3500 times
as much heat as the same volume of air; a 3/4in pipe carrying water is equivalent
to 20 x 12 inch duct or an 18 inch round duct.

Pay attention to first
improving the envelope.

Don’t hire a contractor that
knows almost everything.

IMPO

SR

I find it amazing your gas bill was $175 during the month of September. My was $23.79 for the same month. That is a month with no heating. The boiler must be producing the domestic hot water and doing a very poor job. Either that or you are running a restaurant in your kitchen and drying several loads of wash a day.

What are doing about upgrading insulation and windows?

Don't forget to spray expanding foam insulation around all the places where the walls have communication with the outside. Eg dryer vents, cable wire, pipes ect.

Thanks for all the feedback. mike_home - the gas use in September is driven by pool heating. In July/August the pool basically heats itself enough, but in Sept things started to cool down. Heating the pool is something I am adding in to my thoughts about geothermal. And this year the pool will be closed earlier!

I have a friend who has a solar heater on his roof to heat his pool. I don't know the details, but it is a lot cheaper than burning any fossil fuel. I think he said he can actually make his pool too warm. I would think it would be cheaper than using geothermal.

Are you going to get quotes for geothermal anytime soon? I would be interested in seeing the numbers. You should find a contractor who will do a load calculation. If he refuses then move on to someone else.

I have some firms coming out over the next few weeks. Don't know how long it will take them to turn around and get quotes but will post when I know more. Is load calculation synonymous with Manual J calculation, or are there other types of load calculations?

Load calculation and Manual J calculation are the same thing. The other important one is the Manual D which calculates the sizes of duct work. You could have great equipment, but if the duct work is undersized and poorly configured you will continue to have problems. The fact that you spend so much money on energy and are still uncomfortable suggests the ducting and piping is not good. A good HVAC contractor should inspect everything before giving a quote.

If you are adding additional insulation and making the house tighter, then it needs to be reflected in the load calculation.

Take good notes as you talk to these firms. You may feel you don't know much about HVAC, but as you start talking to these guys you will quickly pick up who knows what they are doing and who does not.