no more pellet stove and fuel oil as primary heat, hello Geothermal

[rparker]

Not an expert on the systems but the office I work for is totally geothermal heated/cooled. It was a new construct building, about 1200 sq.ft. on 2 floors. The geothermal keeps everything a comfy 68* and the TOTAL electric bill is about 120.00 per month. This includes lights. office equipment and heat/cool.
Granted we severly overbuilt the insulation levels and draft sealing (R=45 walls, R=75 roof).
One thing that we did was take the initial design for the system and enlist a hydraulics engineer. The original design had a single 3.5 hp pump to move the water. The engineer figured out that this was a major overdesign (and also huge power consumption). We finally dialled things in to need two 1/6 hp pumps (one push - one pull). With the size of these pumps we could easily run the system and have a photovoltaic solar array designed and ready to go if the price ever becomes affordable.
The payback at $3.00 per gal oil was figured to be 7-10 years. Also we have NO backup system so we are our own test case.
If I ever build new that is the way I will go (and keep the pellet stove for a "boost").

 

[hoverfly]

Geothermal pumps loose efficiency as it gets colder out side? I think they do, but what I do know about regular heat pumps is, that you need supplemental heat. Either electrical, wood or fossil, for the North East when it gets bellow 40F and stays bellow there for some time.

 

[johnny1720]

Geothermal pumps loose efficiency as it gets colder out side? I think they do, but what I do know about regular heat pumps is, that you need supplemental heat. Either electrical, wood or fossil, for the North East when it gets bellow 40F and stays bellow there for some time.

Umm no they actually do not lose efficiency as it gets colder. The COP (coefficient of performance) is usually around 4, so that means for every dollar worth of energy you put in you get 4 dollars out of it. Also the ground is constantly 56 degrees and that does not change. Last winter was one of the coldest and longest here in western new york. My fathers bill was only slightly higher than it was the previous year. What he does is takes his entire electric bill and divides it by the cost of a gallon of fuel oil. Then he says well last months bill was $220 and fuel oil is $3.59, so that means I would have been able to buy 61 gallons of fuel oil. And he knows that he previously used 6 gallons of fuel oil per day. So if he was heating with fuel oil he would have only been able to heat his home for 10 days for $220. And then he would have to have gone amish and be cold for the other 20 days per month.

 

[SmokeyTheBear]

Geothermal pumps loose efficiency as it gets colder out side? I think they do, but what I do know about regular heat pumps is, that you need supplemental heat. Either electrical, wood or fossil, for the North East when it gets bellow 40F and stays bellow there for some time.

That is true only for outside air sourced heat pumps and geothermal units that weren't installed at the correct depth.

 

[Jaugust124]

There was a large upfront cost ($22k or so) that we put in the mortgage

Not to be nitpicky, but amortized over 15 or even 30 years how much is did that system cost. According to my calculations if you had a 30 year loan at 5% the system cost an extra $42,500. A 15 year loan at 5% would cost just over $31,000. 30% back on $22,000 is $6600 you got back. Still quite expensive.

Now of course I have no idea what type of loan you got, how much interest you got it for or for how long. I'm just putting it out there because I think its something that needs to be taken into consideration when planning on putting in such a system.

 

[jtakeman]

Geothermal pumps loose efficiency as it gets colder out side? I think they do, but what I do know about regular heat pumps is, that you need supplemental heat. Either electrical, wood or fossil, for the North East when it gets bellow 40F and stays bellow there for some time.

That is true only for outside air sourced heat pumps and geothermal units that weren't installed at the correct depth.

I need to know more, I too though they were only good for warmer climates. Once the temp dropped below 30ºF they were not as dandy and needed assistence fro another source.

What do I need to look into?

 

[bonesy]

Geothermal pumps loose efficiency as it gets colder out side? I think they do, but what I do know about regular heat pumps is, that you need supplemental heat. Either electrical, wood or fossil, for the North East when it gets bellow 40F and stays bellow there for some time.

That is true only for outside air sourced heat pumps and geothermal units that weren't installed at the correct depth.

I need to know more, I too though they were only good for warmer climates. Once the temp dropped below 30ºF they were not as dandy and needed assistence fro another source.

What do I need to look into?

maybe true for older systems but I have no issues with temps below 20. Goto waterfurnace.com to learn more.

Edit: now don't me wrong, there is a point where they become inefficient in very cold climates but I don't have that issue in northeast PA.

 

[jtakeman]

Geothermal pumps loose efficiency as it gets colder out side? I think they do, but what I do know about regular heat pumps is, that you need supplemental heat. Either electrical, wood or fossil, for the North East when it gets bellow 40F and stays bellow there for some time.

That is true only for outside air sourced heat pumps and geothermal units that weren't installed at the correct depth.

I need to know more, I too though they were only good for warmer climates. Once the temp dropped below 30ºF they were not as dandy and needed assistence fro another source.

What do I need to look into?

maybe true for older systems but I have no issues with temps below 20. Goto waterfurnace.com to learn more.

Thanks! ;-)

 

[bonesy]

There was a large upfront cost ($22k or so) that we put in the mortgage

Not to be nitpicky, but amortized over 15 or even 30 years how much is did that system cost. According to my calculations if you had a 30 year loan at 5% the system cost an extra $42,500. A 15 year loan at 5% would cost just over $31,000. 30% back on $22,000 is $6600 you got back. Still quite expensive.

Now of course I have no idea what type of loan you got, how much interest you got it for or for how long. I'm just putting it out there because I think its something that needs to be taken into consideration when planning on putting in such a system.

sort of true, however add up the cost of X other type of heat for the rest of your life. Still much cheaper. As mentioned above, for every 1 unit of energy it uses, it returns 4 units. My system also preheats domestic hot water before it goes into the electric water heater. Its a byproduct of the heat generated by the compressor, only a few degrees warmer but it all counts. Waterfurnace.com will answer a lot of questions.

 

[Krik]

What do I need to look into?

Ground Source Heat Pump (GHSP). Several forums (forgot which) discuss them in depth.

The air temp doesn't matter like it does for air source heat pumps, because ground temperatures swing much less than the air. However, ground temperatures do vary throughout the U.S. (and even have a seasonal change) at the depths you bury the loops at. So there is some variation in how much pipe you need to bury to get a certain heating/cooling capacity. There are plenty of maps/tables that show ground temps throughout parts of the country. Engineering the loops right is a science - there's software out there to help if you want to do it DIY. Digging the trenches for the loops is quite the job, too. Plus, there are other ways to do it (vertical/wells).

 

[smoke show]

Seems some are confusing heat pumps with actual geo thermal.(water furnace)

 

[johnny1720]

There was a large upfront cost ($22k or so) that we put in the mortgage

Not to be nitpicky, but amortized over 15 or even 30 years how much is did that system cost. According to my calculations if you had a 30 year loan at 5% the system cost an extra $42,500. A 15 year loan at 5% would cost just over $31,000. 30% back on $22,000 is $6600 you got back. Still quite expensive.

Now of course I have no idea what type of loan you got, how much interest you got it for or for how long. I'm just putting it out there because I think its something that needs to be taken into consideration when planning on putting in such a system.

For me no loan,

The old fuel oil furnace was built in 1986, to replace would have been $4k. I wanted central air, that would have been $3k. so for another 10k i am saving $2k per year.

 

[bonesy]

What do I need to look into?

Ground Source Heat Pump (GHSP). Several forums (forgot which) discuss them in depth.

The air temp doesn't matter like it does for air source heat pumps, because ground temperatures swing much less than the air. However, ground temperatures do vary throughout the U.S. (and even have a seasonal change) at the depths you bury the loops at. So there is some variation in how much pipe you need to bury to get a certain heating/cooling capacity. There are plenty of maps/tables that show ground temps throughout parts of the country. Engineering the loops right is a science - there's software out there to help if you want to do it DIY. Digging the trenches for the loops is quite the job, too. Plus, there are other ways to do it (vertical/wells).

correct. And there is more then one type of "loop". It could be vertical wells like I have. Useful if you don't have acres of property to string out horizontal lines everywhere. Or in my case, if you have forest and don't want to cut all the trees down. There are also loops you can lay in a pond, or open loops that can use fresh well water and keep circulating new water from the ground. Mine is a closed loop, meaning it circulates a solution of water and an "antifreeze" type mixture through 3 185' deep dry well holes and back into the unit, ie it is closed and never leaves the lines. These wells are dry and underground, you don't see anything, all the pipes are all connected underground into the basement.

 

[bonesy]

There was a large upfront cost ($22k or so) that we put in the mortgage

Not to be nitpicky, but amortized over 15 or even 30 years how much is did that system cost. According to my calculations if you had a 30 year loan at 5% the system cost an extra $42,500. A 15 year loan at 5% would cost just over $31,000. 30% back on $22,000 is $6600 you got back. Still quite expensive.

Now of course I have no idea what type of loan you got, how much interest you got it for or for how long. I'm just putting it out there because I think its something that needs to be taken into consideration when planning on putting in such a system.

For me no loan,

The old fuel oil furnace was built in 1986, to replace would have been $4k. I wanted central air, that would have been $3k. so for another 10k i am saving $2k per year.

and that my friend is a "net positive cash flow". Its actually paying you each month (figuratively)

 

[Jaugust124]

There was a large upfront cost ($22k or so) that we put in the mortgage

Not to be nitpicky, but amortized over 15 or even 30 years how much is did that system cost. According to my calculations if you had a 30 year loan at 5% the system cost an extra $42,500. A 15 year loan at 5% would cost just over $31,000. 30% back on $22,000 is $6600 you got back. Still quite expensive.

Now of course I have no idea what type of loan you got, how much interest you got it for or for how long. I'm just putting it out there because I think its something that needs to be taken into consideration when planning on putting in such a system.

For me no loan,

The old fuel oil furnace was built in 1986, to replace would have been $4k. I wanted central air, that would have been $3k. so for another 10k i am saving $2k per year.

$3k for central air? Installed? Please elaborate further on that for me. Last summer had a guy check out my system and he wanted to replace the inside and outside unit for $8k-$14k depending on which system I chose. All duct work is already in place.

As for replacing with the geothermal unit, sounds like a very worthwhile investment. I honestly thought that geothermal didn't make sense in the Northeast but only because I don't know a single person who has one. Perhaps its the upfront cost that scares most away. I never really checked it out.

 

[Krik]

Ah found it - not sure if links to other forums are appreciated, but I found a lot of good info on geothermal at http://www.greenbuildingtalk.com/Forums/tabid/53/aff/13/afv/topicsview/Default.aspx

Several DIYers there as well. And yes, even some who successfully did so in the North East.

 

[B-Mod]

I have a 4 ton Waterfurnace geothermal system that provides heating and cooling. It is the most efficient, hands down. I also consider Waterfurnace to be the best. I do not have high electric bills because of the geothermal. My ground loop is not huge, it has 3 vertical dry wells 185' deep. We did it when we built our house in '09. There was a large upfront cost ($22k or so) that we put in the mortgage but we got 30% of that back with the refund. The ROI is very well within 5-7 years on a new constrcution home.

Here's a quote from Waterfurnace:

"The increases in mortgage costs are typically offset by the decreased operating costs of our geothermal systems — providing a net positive cashflow."

Essentially I'm paying a few extra bucks a month in my mortgage instead of paying hundreds per month for any other heating source.

During our first winter (09-10) our highest electric bill was $199. This includes our drinking well (600' down), 80gal electric hot water heat and the electricity for the entire home, including the geo unit. No oil bill, no gas bill, no pellet bill, no coal bill.

Why aren't you pre heating your water with geo?

 

[bonesy]

Why aren't you pre heating your water with geo?

I am...

 

[Jerry_NJ]

I have a two speed (compressor and fan, plus a third lower speed on the fan for air circulation when the unit is not heating or cooling, unless I turn it off) Water Furnace that is about 20 years old.

I gave up reading the thread about 10 posts back because I was reading so much crazy stuff it was giving me a head ach.

The geothermal HP efficiency is independent of the out side air temperature, other than it must deliver more BTUs when it gets colder, or hotter, same for air conditioning. My unit has a COP of 3.6 to 4.0, read that 360% to 400% more efficient than resistive electric heat (an no need to exchange air with the outside to feed a fire/flame, and no loss of humidity due to the need to heat outside air drawn in for the flame). Its cooling is similar with about 20 BTU/Watt, an efficient air-to-air is closer to 12...I think that is called the EER. It too does not depend on air temperature when cooling, so it is just as efficient cooling when the outside is 120 degress as it is when the outside is 80 degrees, or 70 degrees....

Yes, the pumping of the ground loop does raise (when cooling) and lower (when heating), in fact my ground loop has antifreeze so it will continue to work if the loop is driven hard enough to freeze water. That said, my unit's heating efficiency at 3.6 in high speed is with a ground loop temperature of 32 degrees, which it never is. My design is set to be able to maintain the house at 70 degrees with an outside temperature of 0 degrees. It then has available two stages of resistive auxiliary heating, each 5K Watts, or about 17K BTU.

Other than changing filters the unit had Zero maintenance in the first 17 years of its life. Then I had to replace the 3 speed fan and then two years ago the two ground loop pumps. This cost me about $3K total, so over 20 years I have paid $150 a year, less than one pays to have an oil furnace cleaned and adjusted each year. And, I have all new moving parts except the compressor, which I am thinking I may want to plan to replace, maybe this spring...still thinking on that one, the compressor is working great now.

It makes no sense to compare electric bills with anyone but yourself, or with someone for which you have a complete picture of what they are using and how the environment they are conditioning.

I paid about $12,000 for my system 20 years ago, suppose it would cost at least twice that much now. Of course I can replace/upgrade my system and reuses the existing ground loop (which is a dual verticle loop in my case, goes deeply into the water table, thus it too is efficient with exchanging BTUs with the earth. I had help from my electric company, they paid about $3,000 so my cost was $9,000. That works out to $450 a year if I want to consider the unit fully depreciated at this moment. I'd guess I've averaged well over $1,000 a year in saving over the last 5 - 6 years following the rapid run up of energy costs. In fact my annual electric usage compares well with people who heat with oil but heat hot water, cook, and dry cloths with electricity. But, I run the house closer to 65 degrees, less at night and use about 2 cords of seasoned hardwood for supplemental heat, especially when it is real cold out. We also use CFL extensively and have only one refrigerator. I also try to dry cloths on the good old cloths line.

I am not trying to sell Water Furnace, but I can say I have long term experience with a geothermal HP (Ground Source if you prefer). I am pleased with the purchase and believe I'd go that way again, but admit a cost over $25,000 would make me think it over really hard. If rebates got that below $20,000 it seems comparable to what I paid in adjusted dollars.

 

[johnny1720]

The above response reminded me to update this thread,

The new heat pump was installed and made functional on 2/17, it has been running and my pellet stove has not. The one cool thing about this setup is that I can just run the unit on fan , which will allow the pellet stove to heat to circulate in the house.

I had to get a ClimateMaster, I could not choose to get a Waterfurnace because my installer sells ClimateMaster. The installer was top notch and if this thing works as good as I think I may consider selling these for him.

 

[tjnamtiw]

Have a buddy with Geo-Thermal and he still has a pellet stove.

When its cold, its only good to the mid 60's. Afer that, the electric rate goes through the roof (so he says). He has a Breckwell (model? ) freestanding thats vented through his fireplace. I know its a multi fuel model. It has an agitator in it. He rarely ever cleans it. Maybe twice a season. Had it for 5-6 yrs now and only replaced the agitator rod twice (used to burn just corn).

Summer is nice..... Winter. Not so much.

Your buddy has a PROBLEM if his geothermal is only good to mid-60's! A BIG PROBLEM! I've experimented this year heating my house with the pellet stoves at various temperature ranges and recording pellets used. Then this past month I used the regular 15 SEER heat pump at similar temperature swings while monitoring my daily electrical usage with my whole house monitoring system (The Energy Detective) which gives me cost including all the surcharges. I've found that if the outside temp dips to 40 at night and 55 during the day, it costs me about $2.50 to $2 more a day for the heat pump. That's a half a bag of pellets so it makes no sense to use the pellet stoves. It appears that it will only pay to run them when the temperature is close to freezing. Last night it got down to 34 and I used about $3.50 extra electric. The main reason for using the pellet stoves, now that I see the electrical usage, is when the heat pump's efficiency really nose dives below freezing.

 

[Jerry_NJ]

Sorry, I go into this thread from a search on "Water Furnace" and I assumed it was in the Green Room..not Pellet. Yes, I saw the many references to Pellets and that made me check. We still have a common thread, Heat Pumps economics verses... in my case Hard Wood (Wood stove/insert). Again, I have a geothermal so my economics point to using the HP all the time. Still I enjoy a wood fire, in fact there is on in my insert right now. I also think in the case of a ground loop external heat exchange it helps to lower demand by increasing HP efficiency when it is running, that is when my wood fire shuts down the HP, the area around my ground loop warms up, like have the outside temperature around the air-to-air go up, more efficiency for the HP. So, I see the pay-off being both the electricity saved when the HP is off, as well as the increased HP efficiency when it is running following a rest due to the wood heat. I also find the circulating fan on the HP a big help when the wood heat is on as that is a point source and I need to move some of the heat to the back corner of the house on the same floor. The upstairs bedroom get some of the heat too from convection flow, but the study next to the garage needs some help from a resistive space heater when the wood stove has the HP shut down, another negative economic impact of using wood heat (same would apply if I had a pellet insert).

Of course, if the power goes down, and it did that once for 4 days in late October, the wood fire kept the house liveable - one neighbor had to move to a motel for a couple of those days.

 

[DexterDay]

Have a buddy with Geo-Thermal and he still has a pellet stove.

When its cold, its only good to the mid 60's. Afer that, the electric rate goes through the roof (so he says). He has a Breckwell (model? ) freestanding thats vented through his fireplace. I know its a multi fuel model. It has an agitator in it. He rarely ever cleans it. Maybe twice a season. Had it for 5-6 yrs now and only replaced the agitator rod twice (used to burn just corn).

Summer is nice..... Winter. Not so much.

Your buddy has a PROBLEM if his geothermal is only good to mid-60's! A BIG PROBLEM! I've experimented this year heating my house with the pellet stoves at various temperature ranges and recording pellets used. Then this past month I used the regular 15 SEER heat pump at similar temperature swings while monitoring my daily electrical usage with my whole house monitoring system (The Energy Detective) which gives me cost including all the surcharges. I've found that if the outside temp dips to 40 at night and 55 during the day, it costs me about $2.50 to $2 more a day for the heat pump. That's a half a bag of pellets so it makes no sense to use the pellet stoves. It appears that it will only pay to run them when the temperature is close to freezing. Last night it got down to 34 and I used about $3.50 extra electric. The main reason for using the pellet stoves, now that I see the electrical usage, is when the heat pump's efficiency really nose dives below freezing.

By mid 60's. I mean inside temps. Hard to get his house above the mid 60's when its freezing and snowing outside. Above 40-45 he doesnt use the stove. But below that and his Wife cant take 66° inside. She wants it 76° . So they Fire up the Breckwell.

Sorry. I could see how that could be misunderstood. Inside temp of mid 60's when below 25°-30°…

 

[SmokeyTheBear]

The only way to answer any of the dollar questions is to size a system for your house and climate. Then you can figure out the yearly non operation cost of the system then add in the cost of operating such a system.

For example as was pointed out earlier this fixed cost can be substantial.

In some of the system cost figures I've seen this one figure alone amortized is equal to an entire years pellet supply and will be with you for a long while (say 30 years).

Now some of us could take uncle for double or more of a ride tax wise your actual mileage will be different than mine (think reduction in taxes on tax deferred retirement plans).

Get a quote and start your calculators.

 

[tjnamtiw]

By mid 60's. I mean inside temps. Hard to get his house above the mid 60's when its freezing and snowing outside. Above 40-45 he doesnt use the stove. But below that and his Wife cant take 66° inside. She wants it 76° . So they Fire up the Breckwell.

Sorry. I could see how that could be misunderstood. Inside temp of mid 60's when below 25°-30°…

That sounds more like you