Getting quotes for geothermal

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TomatoTomahto
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Getting quotes for geothermal

Post by TomatoTomahto » Thu Aug 30, 2018 6:44 am

I have noticed that there are some forum members who have experience/knowledge of geothermal.

We have a large home near Boston. Some of our AC condensers are old and beginning to show their age. Ditto the air handlers. All are one speed, old, and inefficient. We have an older Viessmann boiler that heats the house via forced air and water (radiant and baseboard); I find it infuriating to heat water this way in the summer to take a shower, but the unit is a marvel of engineering. The service people tell me I need a new burner, soonish, but not as an emergency. We have a lot of solar electricity generated, and intend to get battery storage of daily excess.

In getting quotes for condenser and air handler replacement, I realized that it might make more sense to go geothermal.

Anyone have any things I should look out for? It appears that the condenser units will be in the hall near two bedrooms (air handlers will be in the utility room); are they loud?

I believe that I’m eligible for 30% federal tax credit and $10k MA rebate. I hear that I might also be eligible for a $25k interest free loan. Any other financials to consider?

I am not looking for an early break-even, or even a financial break-even at all. I value being energy self-sufficient and non-polluting highly, and since we have solar, a well, and septic, we should be almost completely independent (other than a small amount of propane).
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Re: Getting quotes for geothermal

Post by JBTX » Thu Aug 30, 2018 12:22 pm

The only thing I know about geothermal is president gwbush's ranch in Texas has geothermal. Good enough for him, good enough for you? :happy

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Re: Getting quotes for geothermal

Post by TomatoTomahto » Thu Aug 30, 2018 12:43 pm

JBTX wrote:
Thu Aug 30, 2018 12:22 pm
The only thing I know about geothermal is president gwbush's ranch in Texas has geothermal. Good enough for him, good enough for you? :happy
If Yale and geothermal are good enough for them, they’re good enough for my family too :D

It’s actually a bit of a surprise down in Oil Country.
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Re: Getting quotes for geothermal

Post by Smoke » Thu Aug 30, 2018 12:58 pm

I have had 4 ton "Ground Source" Heatpump for 9 yrs now. So I can help with some info after I ask a few questions.

1. What is the source of the outside GeoThermal system, Wells/pond/trench/coil bed etc.
2. Do you plan on heating your hot water with this system?
3. How many "Ton" unit are the installers figuring on and did they do a "manual J" to get the size. Or are they just shooting from the hip?

Smoke

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Re: Getting quotes for geothermal

Post by TomatoTomahto » Thu Aug 30, 2018 3:00 pm

Smoke wrote:
Thu Aug 30, 2018 12:58 pm
I have had 4 ton "Ground Source" Heatpump for 9 yrs now. So I can help with some info after I ask a few questions.

1. What is the source of the outside GeoThermal system, Wells/pond/trench/coil bed etc.
Whatever you would call a hole dug in the ground. They called it a “vertical loop.”

2. Do you plan on heating your hot water with this system?
yes, but we will probably tie in an electric booster. First quote calls for 80 gallon tank with “desuperheater.”

3. How many "Ton" unit are the installers figuring on and did they do a "manual J" to get the size. Or are they just shooting from the hip?
They estimate 13 ton based on existing oil and AC capacity.

Smoke
Sorry for the terse answers. Typing on a phone in a parking lot waiting to pick someone up.
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Re: Getting quotes for geothermal

Post by Mountain Fiddle » Thu Aug 30, 2018 3:52 pm

The challenge for your home with regards to geothermal is the hot water baseboard. Most baseboards are designed for 180 deg F water. Geothermal water-to-water systems aren't very efficient above 100 F output, and very few can go above ~120 F for long periods of time.

The air handlers and radiant (assuming you mean radiant floors) could be good candidates for geothermal, otherwise. Also, it sounds like you are on propane, which changes the economics much more in favor of geothermal (compared to natural gas heating).

Note that if you have a large home, the domestic hot water load is usually pretty small compared to the house heating load. That being said, a lot of geothermal heat pumps have an option called a desuperheater, which can take waste heat from cooling in the summertime, and use it to preheat the domestic hot water.

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Re: Getting quotes for geothermal

Post by London » Thu Aug 30, 2018 4:41 pm

Are you planning an open loop or closed loop system? I ask because my house had an open loop system when I bought it and it didn't function properly due to water table. We eventually had to scrap it and convert to natural gas.

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Re: Getting quotes for geothermal

Post by Smoke » Thu Aug 30, 2018 5:05 pm

TomatoTomahto wrote:
Thu Aug 30, 2018 3:00 pm
Smoke wrote:
Thu Aug 30, 2018 12:58 pm
I have had 4 ton "Ground Source" Heatpump for 9 yrs now. So I can help with some info after I ask a few questions.

1. What is the source of the outside GeoThermal system, Wells/pond/trench/coil bed etc.
Whatever you would call a hole dug in the ground. They called it a “vertical loop.”

2. Do you plan on heating your hot water with this system?
yes, but we will probably tie in an electric booster. First quote calls for 80 gallon tank with “desuperheater.”

3. How many "Ton" unit are the installers figuring on and did they do a "manual J" to get the size. Or are they just shooting from the hip?
They estimate 13 ton based on existing oil and AC capacity.

Smoke
Sorry for the terse answers. Typing on a phone in a parking lot waiting to pick someone up.
Don't worry about the answers it's ok.

Outside of Boston and here in the south (Tennessee) I would advise "Wells" as vertical loops in a hole/trench are not deep enough for the extreme hot or in your case cold conditions. If done properly and deep and large enough a vertical loop can work, but it take a huge amount of property surface area to be dug up. Wells are 8" holes that go down hundreds of feet. Mine are 300 ft deep. and have no problem handling the outside temp at that depth. You do not need to hit water btw, they inject a compound for heat transference down the well.

Edit.... I misunderstood Vertical for horizontal, my bad... Vertical is the wells I spoke of, should be fine :beer

Hot water with a desuperheater will not heat all your hot water, which is why they are including an "electric booster" not sure what they mean by that actually. However a desuperheater Needs TWO hot water tanks. The desuperheater heats the first tank to a close to hot temp (preheat) then goes to a conventional electric or propane heater/tank. The preheat is the savings. It will not heat one tank to adequate heat at all for regular usage as it only heats while the unit is running to heat or cool the home. Incoming water temp (winter in Boston 45 deg guess) will change to around 90 ish in the preheat tank, 80 gal. then go to the actual tank electric heater to bring it to 125 ish or whatever ever you set it at, heating from 90 to 125 is cheaper than 45 to 125.

They need to do an engineering study 30 min tops, on your home not just go by what you had installed in the past, if it was the proper size to begin with.

The noise from the air handlers will be the same as any air handlers only new. I would recommend variable speed air handlers.

13 ton is a big one for sure. I don't know about the converting to hydronic so I can't expand on that, I would question instead of one large 13 ton unit to do forced hot air and hydronic have 2 units one for each, but again I don't know.

9 years ago my 4 ton unit with two 300 ft wells cost 24k less the same 30% in tax write offs. and for me I was going to replace the old system anyway so subtract the cost of conventional heat pump about 6k, These units are supposed to last about 25 yrs, due to the less stress on them so I figure double the lifespan. about break even... Then there is the savings in elec over 25 yrs.

I am very happy I made the switch, just be aware that the heat is not instant coming out of the vents it's a more gradual heat that some do not like.
But ground source heatpumps do not care what the air temp is outside as it is usually around a constant 55 deg 300 ft down.
Last edited by Smoke on Thu Aug 30, 2018 5:37 pm, edited 2 times in total.

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TomatoTomahto
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Re: Getting quotes for geothermal

Post by TomatoTomahto » Thu Aug 30, 2018 5:34 pm

Mountain Fiddle wrote:
Thu Aug 30, 2018 3:52 pm
The challenge for your home with regards to geothermal is the hot water baseboard. Most baseboards are designed for 180 deg F water. Geothermal water-to-water systems aren't very efficient above 100 F output, and very few can go above ~120 F for long periods of time.

The air handlers and radiant (assuming you mean radiant floors) could be good candidates for geothermal, otherwise. Also, it sounds like you are on propane, which changes the economics much more in favor of geothermal (compared to natural gas heating).

Note that if you have a large home, the domestic hot water load is usually pretty small compared to the house heating load. That being said, a lot of geothermal heat pumps have an option called a desuperheater, which can take waste heat from cooling in the summertime, and use it to preheat the domestic hot water.
I haven't figured out exactly how the baseboards work; they're a minimal part of the heating. I wonder if they were electric add-ons for a part of the house that wasn't sufficiently warmed with the main system.
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Re: Getting quotes for geothermal

Post by TomatoTomahto » Thu Aug 30, 2018 5:37 pm

London wrote:
Thu Aug 30, 2018 4:41 pm
Are you planning an open loop or closed loop system? I ask because my house had an open loop system when I bought it and it didn't function properly due to water table. We eventually had to scrap it and convert to natural gas.
What I know about geothermal can fit into a thimble, but my impression is that trying to install an open loop system in our town would have the wrath of the health department come crashing down on our heads. This is a town that posts notices that "Roadways are not salted," and they truly don't salt them. Our well water, and I gather the whole underlying aquifer, has incredibly good-tasting water, and the town protects it with vigilance. So, it's a closed loop system.
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Re: Getting quotes for geothermal

Post by TomatoTomahto » Thu Aug 30, 2018 5:52 pm

Smoke wrote:
Thu Aug 30, 2018 5:05 pm

Hot water with a desuperheater will not heat all your hot water, which is why they are including an "electric booster" not sure what they mean by that actually. However a desuperheater Needs TWO hot water tanks. The desuperheater heats the first tank to a close to hot temp (preheat) then goes to a conventional electric or propane heater/tank. The preheat is the savings. It will not heat one tank to adequate heat at all for regular usage as it only heats while the unit is running to heat or cool the home. Incoming water temp (winter in Boston 45 deg guess) will change to around 90 ish in the preheat tank, 80 gal. then go to the actual tank electric heater to bring it to 125 ish or whatever ever you set it at, heating from 90 to 125 is cheaper than 45 to 125.
After we remove the oil burner, we will have lots of room for water tanks. The 80 gallon one is, I guess, for the "preheated" water, and the quote doesn't include the second tank.
They need to do an engineering study 30 min tops, on your home not just go by what you had installed in the past, if it was the proper size to begin with.
I will ask about that, if not for the first company, then the second.
The noise from the air handlers will be the same as any air handlers only new. I would recommend variable speed air handlers.
The air handlers will be where they are now, and they aren't loud. I'm worried about the condensers, which will be closer to the bedrooms. I assume they're much quieter than an outdoor AC condenser.
13 ton is a big one for sure. I don't know about the converting to hydronic so I can't expand on that, I would question instead of one large 13 ton unit to do forced hot air and hydronic have 2 units one for each, but again I don't know.
There would be a total of 4 air handlers with 4 condensers to match (2x 2 ton, 2x 3 ton) and then one to do the water-to-water. So there would be 5 vertical loops. From what I understand, they have to be 20' apart from each other, so it's a good thing we have a lot of yard to give this install. The quote says "average depth of 170' per ton."
I am very happy I made the switch, just be aware that the heat is not instant coming out of the vents it's a more gradual heat that some do not like.
That's actually a plus for me. I don't like the too hot/too cold forced air; my previous house had steam radiators, and I loved their gradual nature.
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Re: Getting quotes for geothermal

Post by Smoke » Thu Aug 30, 2018 6:08 pm

TomatoTomahto wrote:
Thu Aug 30, 2018 5:52 pm
Smoke wrote:
Thu Aug 30, 2018 5:05 pm

Hot water with a desuperheater will not heat all your hot water, which is why they are including an "electric booster" not sure what they mean by that actually. However a desuperheater Needs TWO hot water tanks. The desuperheater heats the first tank to a close to hot temp (preheat) then goes to a conventional electric or propane heater/tank. The preheat is the savings. It will not heat one tank to adequate heat at all for regular usage as it only heats while the unit is running to heat or cool the home. Incoming water temp (winter in Boston 45 deg guess) will change to around 90 ish in the preheat tank, 80 gal. then go to the actual tank electric heater to bring it to 125 ish or whatever ever you set it at, heating from 90 to 125 is cheaper than 45 to 125.
After we remove the oil burner, we will have lots of room for water tanks. The 80 gallon one is, I guess, for the "preheated" water, and the quote doesn't include the second tank.

It may be they are going to install a tank-less electric water heater then? Not sure what they mean by booster :confused
They need to do an engineering study 30 min tops, on your home not just go by what you had installed in the past, if it was the proper size to begin with.
I will ask about that, if not for the first company, then the second.
The noise from the air handlers will be the same as any air handlers only new. I would recommend variable speed air handlers.
The air handlers will be where they are now, and they aren't loud. I'm worried about the condensers, which will be closer to the bedrooms. I assume they're much quieter than an outdoor AC condenser.

My 4 ton 2 speed unit with the compressor and air handler (it's one unit not split) is in my basement. even when I stand next to it it is very quiet especially when compared to my old outside unit. There are no condensers in a geo unit, the condensers are the wells. :wink:
13 ton is a big one for sure. I don't know about the converting to hydronic so I can't expand on that, I would question instead of one large 13 ton unit to do forced hot air and hydronic have 2 units one for each, but again I don't know.
There would be a total of 4 air handlers with 4 condensers to match (2x 2 ton, 2x 3 ton) and then one to do the water-to-water. So there would be 5 vertical loops. From what I understand, they have to be 20' apart from each other, so it's a good thing we have a lot of yard to give this install. The quote says "average depth of 170' per ton."

20 ft apart is the same as mine
Ah, 4 units in total, why are they spitting the units? compressor and air handler... My climatemaster is one unit compressor under the air handler in the same metal unit.
I am very happy I made the switch, just be aware that the heat is not instant coming out of the vents it's a more gradual heat that some do not like.
That's actually a plus for me. I don't like the too hot/too cold forced air; my previous house had steam radiators, and I loved their gradual nature.
:sharebeer

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TomatoTomahto
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Re: Getting quotes for geothermal

Post by TomatoTomahto » Fri Aug 31, 2018 2:03 am

Hey Smoke, shame on me for not noticing that you’re a new poster in the forum. Welcome! Thanks for posting.
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Re: Getting quotes for geothermal

Post by Valuethinker » Fri Aug 31, 2018 3:07 am

TomatoTomahto wrote:
Thu Aug 30, 2018 5:37 pm
London wrote:
Thu Aug 30, 2018 4:41 pm
Are you planning an open loop or closed loop system? I ask because my house had an open loop system when I bought it and it didn't function properly due to water table. We eventually had to scrap it and convert to natural gas.
What I know about geothermal can fit into a thimble, but my impression is that trying to install an open loop system in our town would have the wrath of the health department come crashing down on our heads. This is a town that posts notices that "Roadways are not salted," and they truly don't salt them. Our well water, and I gather the whole underlying aquifer, has incredibly good-tasting water, and the town protects it with vigilance. So, it's a closed loop system.
I believe the vast majority are closed loop systems. The loss of efficiency due to heat exchange (between the self contained coil and the ground) should be de minimis -- a few per cent.

The main problem is Coefficient of Performance (which can be up to 5.0 i.e. 5 kwhr of heat or cool moved for 1 kwhr of electricity) falls with an increase in difference between input and output temperatures.

Thus the systems usually produced significantly lower heat water (for rads) than a standard furnace ("boiler" in the UK) would do. Otherwise their COP looks lousy (anything below say 2.0 say).

For an old house, which is not well insulated, this is problematic. The way you run a HP is counter intuitive: you run it low and slow all the time, rather than (usual with a standard furnace) you bang it down when you are out and up when you get home (or an hour beforehand if you have internet controllable).

Given that old houses tend to leak heat, it may mean it is not comfortably warm at some times. In effect you have to oversize for that (with a leaky enough house, it just won't work). And you may need some kind of backup heating system (electric bar has COP of 1.0 by definition).

https://www.eia.gov/energyexplained/ind ... heat_pumps

https://www.energystar.gov/products/hea ... geothermal

https://www.energystar.gov/productfinde ... ps/results

https://www.energystar.gov/products/hea ... t_criteria

https://www.energystar.gov/index.cfm?c= ... _pump_spec

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Re: Getting quotes for geothermal

Post by Valuethinker » Fri Aug 31, 2018 3:41 am

Note because of the way geothermal works you'd need massive energy storage to be "Off grid".

Alternatives:

- a really big heat store (superinsulated hot water tank or basically pebbles heated by hot air)

- you could do a solar hot water arrangement connected to the above

- I am not sure a battery pack would do it at a feasible size - think you need total output from HP at say 30 kw (Europe we do things in kw & kwhr, conversion factors are 3.8 litres/ US gal, from memory 1 kwhr = 3466 BTU (have not googled). So that is 10kw and say it runs 12 hrs/ day - that's 120 kwhr/ day. Now I may have overestimated by 50% but 60 kwhr p/day is still significant.

https://nottenergy.com/our-services/ene ... omparison/ ("gas oil" is heating oil, LPG is propane)

Our heating oil costs are pretty much yours I think (heating oil is not taxed in the UK whereas gasoline is heavily taxed).

https://www.rensmart.com/Calculators/HeatingOil

https://www.monikie.org.uk/fuel-calorific-values.htm

In practice you are going to use the grid (at night, in winter; at peak summer cooling). The electricity grid is kind of like the internet in that its universal availability and reliability (in aspiration at least) creates its own pure Public Good (in an economic sense). Not that we are using it at any given moment, but we can.

Note

In an old house, hot water demand is probably 10% of total energy demand - unless you run a lot of hot showers. By American standards I have a small (say 1500 square feet) Victorian terrace (row) with minimal insulation (but average winter temperature is above freezing) with 2 people and that's about the ratio for us (superinsulated 55 US gallon hot water tank) although UK houses use an "indirect" system which heats both hot water and rads from the same boiler on separate circuits.

Thus, a separate Hot Water system may be justified. Whether propane or electric coil, it should not be a huge user -- electric HP (air source HP) hot water heaters are certainly available. That saves the problem of running the HP just to heat water.
Last edited by Valuethinker on Fri Aug 31, 2018 4:55 am, edited 1 time in total.

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Re: Getting quotes for geothermal

Post by Carl53 » Fri Aug 31, 2018 4:38 am

Our home had a "Cadillac" level geothermal system when we purchased it back in the 80's. I am surprised at the need for 13T. Ours was 4.5 ton for 2200 sq ft house. We are in Ohio so I doubt that your winters/summers are much worse than ours. When the geo was working properly, the emergency backup heat never kicked in even when it was -10F for a week.

In our case we had a horizontal installation of supposedly 1400 ft of line. I loved the system until components started failing. The desuperheater supplied our hot water needs at about 170F. If AC or furnace were not running, the unit would as necessary run just for hot water replenishment in the 70 gallon tank, or to heat the pool. There was an automatic mixer valve to cool to a tolerable temperature.

While heating ours put out around 100+F heated air.

The compressor/pumps/automatic valving were not noisy.

I did not replace it twenty years ago with a new geothermal due to the installed costs being quoted as double what a gas furnace, gas hot water heater and new AC cost despite having the ground loop already installed. Also, of course natural gas had become available.

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Re: Getting quotes for geothermal

Post by TomatoTomahto » Fri Aug 31, 2018 6:37 am

- I am not sure a battery pack would do it at a feasible size - think you need total output from HP at say 30 kw (Europe we do things in kw & kwhr, conversion factors are 3.8 litres/ US gal, from memory 1 kwhr = 3466 BTU (have not googled). So that is 10kw and say it runs 12 hrs/ day - that's 120 kwhr/ day. Now I may have overestimated by 50% but 60 kwhr p/day is still significant.
...
In practice you are going to use the grid (at night, in winter; at peak summer cooling). The electricity grid is kind of like the internet in that its universal availability and reliability (in aspiration at least) creates its own pure Public Good (in an economic sense). Not that we are using it at any given moment, but we can.
There's an app for that: :D Looking at the app for power generation before we bought the house, the electric production in summer months has been above 4MWh every month, with only intermittent slow days, so we should be good.

Winters are another matter. The worst month (January 2017) generated 1.33 MWh, with some zero production days. That might be a data anomaly, in that if the system is not connected to the utility, no data is gathered. There were many power outages that month, and there were also intermittent Internet outages which also interfere with data collection.

In any case, in Massachusetts, it is a requirement to be connected to the grid. I want batteries not to be "off the grid," but to be less dependent on the grid. If we have a power outage, we currently rely on a 7KWh propane generator, which keeps the essentials going. I would like to have a few days of stored electricity. If only one could discharge our car's battery; there is 90 KWh in my Model X.

I hope to know more about the batteries when Tesla finishes its (I hope) final inspection Sunday (yes, they're coming out the Sunday before Labor Day!!!).
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Re: Getting quotes for geothermal

Post by TomatoTomahto » Fri Aug 31, 2018 6:45 am

Carl53 wrote:
Fri Aug 31, 2018 4:38 am
Our home had a "Cadillac" level geothermal system when we purchased it back in the 80's. I am surprised at the need for 13T. Ours was 4.5 ton for 2200 sq ft house. We are in Ohio so I doubt that your winters/summers are much worse than ours. When the geo was working properly, the emergency backup heat never kicked in even when it was -10F for a week.
We have an inexcusably large house (over 7k SF). We don't use most of it, most of the time. We fell in love with the grounds mostly, and the too-large house was what came with the land. We love the house, but when the kids are away at school, we don't heat/cool athe majority of it.

In our case we had a horizontal installation of supposedly 1400 ft of line. I loved the system until components started failing. The desuperheater supplied our hot water needs at about 170F. If AC or furnace were not running, the unit would as necessary run just for hot water replenishment in the 70 gallon tank, or to heat the pool. There was an automatic mixer valve to cool to a tolerable temperature.
Was the pool heater connection difficult to install? We currently have propane heaters for pool and spa.

The compressor/pumps/automatic valving were not noisy.
Would you say that the compressor was tolerably quiet to have within 20 feet of a bedroom?

I did not replace it twenty years ago with a new geothermal due to the installed costs being quoted as double what a gas furnace, gas hot water heater and new AC cost despite having the ground loop already installed. Also, of course natural gas had become available.
I gather that, had it not been for cost, you would have replaced it with new geothermal.
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Re: Getting quotes for geothermal

Post by Valuethinker » Fri Aug 31, 2018 7:23 am

TomatoTomahto wrote:
Fri Aug 31, 2018 6:37 am
- I am not sure a battery pack would do it at a feasible size - think you need total output from HP at say 30 kw (Europe we do things in kw & kwhr, conversion factors are 3.8 litres/ US gal, from memory 1 kwhr = 3466 BTU (have not googled). So that is 10kw and say it runs 12 hrs/ day - that's 120 kwhr/ day. Now I may have overestimated by 50% but 60 kwhr p/day is still significant.
...
In practice you are going to use the grid (at night, in winter; at peak summer cooling). The electricity grid is kind of like the internet in that its universal availability and reliability (in aspiration at least) creates its own pure Public Good (in an economic sense). Not that we are using it at any given moment, but we can.
There's an app for that: :D Looking at the app for power generation before we bought the house, the electric production in summer months has been above 4MWh every month, with only intermittent slow days, so we should be good.

Winters are another matter. The worst month (January 2017) generated 1.33 MWh, with some zero production days. That might be a data anomaly, in that if the system is not connected to the utility, no data is gathered. There were many power outages that month, and there were also intermittent Internet outages which also interfere with data collection.

In any case, in Massachusetts, it is a requirement to be connected to the grid. I want batteries not to be "off the grid," but to be less dependent on the grid. If we have a power outage, we currently rely on a 7KWh propane generator, which keeps the essentials going. I would like to have a few days of stored electricity. If only one could discharge our car's battery; there is 90 KWh in my Model X.

I hope to know more about the batteries when Tesla finishes its (I hope) final inspection Sunday (yes, they're coming out the Sunday before Labor Day!!!).
If possible I'd be tempted to look into Solar Hot Water and a big hot water store - SHW usually does not pay off in any reasonable time frame but your situation is unusual. That could meet 100% of your HW needs in summer and a decent fraction most other times except say Dec- March - you'd still need a water heater though.

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Re: Getting quotes for geothermal

Post by Valuethinker » Fri Aug 31, 2018 7:27 am

TomatoTomahto wrote:
Fri Aug 31, 2018 6:45 am
Carl53 wrote:
Fri Aug 31, 2018 4:38 am
Our home had a "Cadillac" level geothermal system when we purchased it back in the 80's. I am surprised at the need for 13T. Ours was 4.5 ton for 2200 sq ft house. We are in Ohio so I doubt that your winters/summers are much worse than ours. When the geo was working properly, the emergency backup heat never kicked in even when it was -10F for a week.
We have an inexcusably large house (over 7k SF). We don't use most of it, most of the time. We fell in love with the grounds mostly, and the too-large house was what came with the land. We love the house, but when the kids are away at school, we don't heat/cool athe majority of it.
It has to be said I do not envy you your property taxes or municipal charges. Nor your repair bills. Until I owned a house I did not realize how much these rack up!

My father grew up in very large, undermaintained, English country houses. Whenever we would walk by a large house when we were growing up, I would say "that looks like a very nice house" and he would say "always something to clean and to fix in a big house". He spoke from family experience (his father was often away on overseas military postings).

Eventually his parents (second) last house was sold to a local council and used as a nursing home. When it became too expensive to maintain, they knocked it down. Because it was on the south coast, it had a very lush garden (palm trees etc. - the Gulf Stream effect) which became sadly overgrown.

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Re: Getting quotes for geothermal

Post by Carl53 » Fri Aug 31, 2018 7:43 am

TomatoTomahto wrote:
Fri Aug 31, 2018 6:45 am
Carl53 wrote:
Fri Aug 31, 2018 4:38 am
Our home had a "Cadillac" level geothermal system when we purchased it back in the 80's. I am surprised at the need for 13T. Ours was 4.5 ton for 2200 sq ft house. We are in Ohio so I doubt that your winters/summers are much worse than ours. When the geo was working properly, the emergency backup heat never kicked in even when it was -10F for a week.
We have an inexcusably large house (over 7k SF). We don't use most of it, most of the time. We fell in love with the grounds mostly, and the too-large house was what came with the land. We love the house, but when the kids are away at school, we don't heat/cool athe majority of it.

In our case we had a horizontal installation of supposedly 1400 ft of line. I loved the system until components started failing. The desuperheater supplied our hot water needs at about 170F. If AC or furnace were not running, the unit would as necessary run just for hot water replenishment in the 70 gallon tank, or to heat the pool. There was an automatic mixer valve to cool to a tolerable temperature.
Was the pool heater connection difficult to install? We currently have propane heaters for pool and spa.
The pool heater connection was already installed when we bought the house. The geothermal unit was designed for pool heating as a tertiary option. The system logic made hot water top priority, then heating/AC and lastly pool heating. It was plumbed with two one-inch copper pipes from a special heat exchanger in the house to the pool. Those pipes were connected to either side of a valve that could be throttled in the pool pump/filter return line going to the pool. The lines were plumbed with drains for winter. We now use natural gas for pool heating.


The compressor/pumps/automatic valving were not noisy.
Would you say that the compressor was tolerably quiet to have within 20 feet of a bedroom?
Our was.

I did not replace it twenty years ago with a new geothermal due to the installed costs being quoted as double what a gas furnace, gas hot water heater and new AC cost despite having the ground loop already installed. Also, of course natural gas had become available.
I gather that, had it not been for cost, you would have replaced it with new geothermal.
That was my first choice. Had three different companies out looking to replace the components in the house. They all wanted 2X+ the cost of the high efficiency gas furnace, hot water tank, and air conditioner plus about 200 feet of gas line despite us already having the geothermal piping in the yard. None of those replacement units would heat the pool nor were able to do more than supplement the preheating of the hot water tank. A few years later we added a natural gas heater for the pool.

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Re: Getting quotes for geothermal

Post by WhyNotUs » Fri Aug 31, 2018 7:55 am

FWIW, the system that you are seeking is really geo-exchange rather than geothermal.
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TomatoTomahto
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Re: Getting quotes for geothermal

Post by TomatoTomahto » Fri Aug 31, 2018 8:03 am

Valuethinker wrote:
Fri Aug 31, 2018 7:27 am
TomatoTomahto wrote:
Fri Aug 31, 2018 6:45 am
Carl53 wrote:
Fri Aug 31, 2018 4:38 am
Our home had a "Cadillac" level geothermal system when we purchased it back in the 80's. I am surprised at the need for 13T. Ours was 4.5 ton for 2200 sq ft house. We are in Ohio so I doubt that your winters/summers are much worse than ours. When the geo was working properly, the emergency backup heat never kicked in even when it was -10F for a week.
We have an inexcusably large house (over 7k SF). We don't use most of it, most of the time. We fell in love with the grounds mostly, and the too-large house was what came with the land. We love the house, but when the kids are away at school, we don't heat/cool athe majority of it.
It has to be said I do not envy you your property taxes or municipal charges. Nor your repair bills. Until I owned a house I did not realize how much these rack up!

My father grew up in very large, undermaintained, English country houses. Whenever we would walk by a large house when we were growing up, I would say "that looks like a very nice house" and he would say "always something to clean and to fix in a big house". He spoke from family experience (his father was often away on overseas military postings).

Eventually his parents (second) last house was sold to a local council and used as a nursing home. When it became too expensive to maintain, they knocked it down. Because it was on the south coast, it had a very lush garden (palm trees etc. - the Gulf Stream effect) which became sadly overgrown.
2/3 of our property is "Protected Wetlands," which we agree to leave wild and forested. It apparently is home to a special kind of frog; our pond and pool are home to more pedestrian type frogs. That saves us quite a bit on taxes. For comparison, our more than 20 acres of land pays just slightly more than we did for half an acre in a NJ suburb of NYC. Long live special frogs!!!

We could afford this house because most buyers were scared off by the maintenance and repair issues. Our realtor said that most potential buyers looked at the large ground-based solar array and wanted nothing so unappealing on their property; I looked at it and smiled at the organic way I could charge my Tesla. It had been well maintained, but I think in the last 5 years of ownership, the previous owner was weary of it, and did let some things slip. I'm a young 67 year old (ha!), retired, and still have the appetite for it. I am simplifying the house at every turn. For example, I am replacing the app-based lighting scheme with switches (remember those?); I have coined what I think is a neologism: "deappifying."
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Re: Getting quotes for geothermal

Post by TomatoTomahto » Fri Aug 31, 2018 8:04 am

WhyNotUs wrote:
Fri Aug 31, 2018 7:55 am
FWIW, the system that you are seeking is really geo-exchange rather than geothermal.
I guess the incorrect term has come into common usage.
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Re: Getting quotes for geothermal

Post by cpumechanic » Fri Aug 31, 2018 8:56 am

FWIW I would not worry much about hot water. You can install an electric one with a heat pump on top that is very efficient and will cool and dehumidify the area around it. Cost is $1000 or so at the local big box stores, and you can claim the energy credit, and check to see if your local electric supplier has any rebates.

The heatpump on top is a little noisy so you would not want it installed in a bedroom .

This link shows a comparison of various sources of hot water heat.

https://www.efficiencymaine.com/at-home ... omparison/

I am a little surprised at the low yearly cost mentioned at that link ($144/yr) but by comparison it confirms that this choice is best for hot water generation. I would not mess with any other approach for my hot water.

My opinion for what it is worth.

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Re: Getting quotes for geothermal

Post by Valuethinker » Fri Aug 31, 2018 9:10 am

TomatoTomahto wrote:
Fri Aug 31, 2018 8:03 am


2/3 of our property is "Protected Wetlands," which we agree to leave wild and forested. It apparently is home to a special kind of frog; our pond and pool are home to more pedestrian type frogs. That saves us quite a bit on taxes. For comparison, our more than 20 acres of land pays just slightly more than we did for half an acre in a NJ suburb of NYC. Long live special frogs!!!
Amphibians are the canary in the coal mine of any environmental change. The outbreaks of frog-killing fungi out there are a warning. Amphibians are the first, but seldom the last, thing to die as change takes hold.
We could afford this house because most buyers were scared off by the maintenance and repair issues. Our realtor said that most potential buyers looked at the large ground-based solar array and wanted nothing so unappealing on their property; I looked at it and smiled at the organic way I could charge my Tesla. It had been well maintained, but I think in the last 5 years of ownership, the previous owner was weary of it, and did let some things slip. I'm a young 67 year old (ha!), retired, and still have the appetite for it. I am simplifying the house at every turn. For example, I am replacing the app-based lighting scheme with switches (remember those?); I have coined what I think is a neologism: "deappifying."
It was reported here this week (UK) that ex partners are using Internet of Things to track and terrorize their former (female) partners. For example turning the thermostat up too high or shutting it off on cold days.

We have not even begun to grasp the risks and implications of IOT, mobile connectivity etc. Alexa etc. are listening to you even, apparently, when switched off.

This does not make me want to install Nest.

Reminded of 1970s thriller films The Groundstar Conspiracy (George Peppard) which hangs on a tape of a phonecall and The Anderson Tapes (Sean Connery) which hangs on electronic surveillance. Also of course The Conversation (with Gene Hackman as the sound man).

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Re: Getting quotes for geothermal

Post by TomatoTomahto » Sun Sep 30, 2018 10:34 am

Update:

The company I felt best about gave me a quote of $135k, less $40.6k (federal tax credit) less $10k (MA Clean Energy Rebate) less $11k (estimated MA DOER credits). We are eligible for $25k MA heat loan (7 years at 0% interest).

We are responsible for removing oil, oil tank (above ground), and boiler. We are also responsive for water heater. Connecting to desuperheater can be done concurrently or later.

A detailed manual J test will take place in a month or so.

The J test will tell us a lot about the radiant heat in the master; there’s a $6k option (net of incentives) to provide that via geothermal.


ETA: the units are not specified in tons, but rather BTU peak, but a rough conversion makes it a 3 ton, a 4 ton, and a 5 ton units. In finding the conversion factor, I learned that the Ton Unit Measure derived from the days of cooling via . . . ICE! A refrigeration ton is roughly 12k BTU, or 3.5 kW. Thank God everyone uses different units!
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Re: Getting quotes for geothermal

Post by Valuethinker » Mon Oct 01, 2018 3:42 am

TomatoTomahto wrote:
Sun Sep 30, 2018 10:34 am
Update:

The company I felt best about gave me a quote of $135k, less $40.6k (federal tax credit) less $10k (MA Clean Energy Rebate) less $11k (estimated MA DOER credits). We are eligible for $25k MA heat loan (7 years at 0% interest).

We are responsible for removing oil, oil tank (above ground), and boiler. We are also responsive for water heater. Connecting to desuperheater can be done concurrently or later.

A detailed manual J test will take place in a month or so.

The J test will tell us a lot about the radiant heat in the master; there’s a $6k option (net of incentives) to provide that via geothermal.


ETA: the units are not specified in tons, but rather BTU peak, but a rough conversion makes it a 3 ton, a 4 ton, and a 5 ton units. In finding the conversion factor, I learned that the Ton Unit Measure derived from the days of cooling via . . . ICE! A refrigeration ton is roughly 12k BTU, or 3.5 kW. Thank God everyone uses different units!
At that kind of capital expenditure I would be surprised if you could make it pay? And I thought upgrading my gas-fired boiler to 90% efficiency and a super insulated tank and new rads was an expensive business (around £15k or USD 20k). And we use indirect heating i.e. the boiler also provides the hot water.

The history of the New England ice industry is fascinating. Way into the late 19th century, they used to ship ice to Europe (there's a canal museum in London in an old ice house in Kings X which only shut down in the 1930s).

So it's perhaps not surprising the metric used was tons of ice. And water is so ubiquitous and the freezing temperature of water such a universal constant, that it's not a bad choice.

But yes the kilowatt hr, BTU, tons conversions make my head hurt ;-). Not to mention tons and tonnes ;-). From memory, the British ton is not the America ton (it's to do with short tons and long tons) and neither is a tonne ;-). And do I mean kwhr or kw to BTU?

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Re: Getting quotes for geothermal

Post by TomatoTomahto » Mon Oct 01, 2018 7:03 am

I was discussing the "make it pay" issue with a friend of mine. He's written a book about achieving a Zero Carbon Home, and his opinion is (strongly) that the economic way to do it is with air based heat pumps. He also emphasizes insulation, triple glazed windows (if current windows need replacing), and PV panels.

He lives near me (Boston area) and has kept his oil burner, which he says he uses fewer than 45 days per year. On a strictly cost basis, that might be right for us also, but 1-there are repairs that should take place on our oil burner, 2-I can't stand the stink, and 3-I don't know if we'd have room for all the other equipment if we kept the large Viessmann just for occasional use but replaced hot water (domestic, radiant, and baseboard) generation with heat pumps. I don't think air based heat pumps, as much better as they've gotten over the past few years, could heat this large house in the winter on the coldest days. There are architectural reasons that we can't sufficiently insulate the house (structural fieldstone, no crawl space, no attic, etc.).

It is difficult to place a dollar value on it, but geothermal is a quieter source of heating and cooling than air-sourced heat pumps. Our house is well off the road, and we have the sounds of hawks, turkeys, coyotes (not my favorite sound), frogs, and all kinds of birds here.

There is an additional dollar value in achieving not only a zero carbon home, but one that brings its own water from underground using well pumps powered by solar, heats it without fossil fuels, and returns it to the ground via septic. I'm waiting for battery storage 400A gateways (currently (ha!) limited to 200A), which is a few years away, but that would make us electrically independent. I can't tell you how many dollars that's worth, but it's not $0.

The cost would be considerably less if we didn't opt for the "top of the line" system. The pumps are all infinitely variable speed, so I'm hoping that the system doesn't cycle often, if at all, and that a steady slow stream of conditioned air is possible once we have it dialed in. Our old home used steam radiators for the master suite, and while they aren't quiet, I loved their steady heat. I hate the sound of air conditioners turning on and the dramatic changes in room temperature as heat and cool are manipulated by forced air systems; my expectation is that a smoother gradient will feel much more comfortable.

The installer had initially spec'ed a system one notch down from the top. That probably makes economic sense, but I am not sure that's optimal for a system that will last many years.

ETA: It is almost as though the industry doesn't want to progress sustainable heating and cooling, electric vehicles, etc., by their use of conflicting and confusing units of measure. Maybe everyone should agree to specify in kW, so that consumers could do easy comparisons of quotes.
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Re: Getting quotes for geothermal

Post by Wellfleet » Mon Oct 01, 2018 7:22 am

Respectfully, I think you are getting taken for a ride. At that kind of cost I would recommend a net zero type engineer/architect and start from scratch. More of a general commentary, but if this company is specifying $135,000 systems for a 7,000 square foot house there is no future in the market.

You could replace the boiler ($20K maybe?, install a generator, be 100% self sufficient and then make a big donation for conservation land preservation that would be much more impactful for generations to come.

I disagree with the statement about ASHPs. I am increasingly impressed with them at my home and at new commercial buildings/libraries, etc. They are absolutely silent and and the variable speed fans eliminate the freezing or blast of hot air feeling.

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Re: Getting quotes for geothermal

Post by TomatoTomahto » Mon Oct 01, 2018 7:40 am

Wellfleet wrote:
Mon Oct 01, 2018 7:22 am
Respectfully, I think you are getting taken for a ride. At that kind of cost I would recommend a net zero type engineer/architect and start from scratch. More of a general commentary, but if this company is specifying $135,000 systems for a 7,000 square foot house there is no future in the market.

You could replace the boiler ($20K maybe?, install a generator, be 100% self sufficient and then make a big donation for conservation land preservation that would be much more impactful for generations to come.

I disagree with the statement about ASHPs. I am increasingly impressed with them at my home and at new commercial buildings/libraries, etc. They are absolutely silent and and the variable speed fans eliminate the freezing or blast of hot air feeling.
I will, in turn, respectfully disagree with you. I have consulted with a net zero type engineer. My choices are more driven by what I feel comfortable doing than what saves me money.

The company had initially specified a system that cost less. I insisted on the luxury version.

Replacing the boiler is abhorrent to me. It might make sense financially, but the thought makes me gag. In a similar vein, my Tesla might not be a winner economically, and perhaps my next car will be a less over-the-top EV, but there are some things that I don't want to do, and which we have sufficient assets to allow me to be stubborn on.

We do have a generator (8kW), but upgrading it to be 100% self-sufficient is probably impossible; even making the house semi-self-sufficient would call for at least a 20kW, and possibly larger, generator. I would have a choice of propane (current) or diesel generator; I don't want to invest further in fossil fuels, but am okay with leaving propane where it is (stove, generator, pool heater) for the time being. The house has 400A of service. The 8kW generator powers essential parts of the house, but a much larger generator would involve putting in a new propane tank.
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Re: Getting quotes for geothermal

Post by TomatoTomahto » Mon Oct 01, 2018 8:23 am

I should add that it’s a 50+ year old house (with a substantial renovation 30 years ago). I’ve consulted with an engineer and an architect; we have limited options on making it more thermally insulated without completely changing the nature of the house. So, we have to overcome some of those failings with brute force.

For example, as lovely as all the fieldstone is, and as thick as it is, its R-value is low. It’s much more effective as a WiFi insulator :D
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Re: Getting quotes for geothermal

Post by Wellfleet » Mon Oct 01, 2018 8:41 am

OK fair enough. At least be a good Boglehead and get three quotes. :sharebeer

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Re: Getting quotes for geothermal

Post by TomatoTomahto » Mon Oct 01, 2018 9:17 am

Wellfleet wrote:
Mon Oct 01, 2018 8:41 am
OK fair enough. At least be a good Boglehead and get three quotes. :sharebeer
Well, almost. I did get two quotes, and contacted a few more companies that I ruled out just based on their telephone demeanor. I got lots of personal reviews from engineers, neighbors, and architects. The company I selected was well ahead of the others in terms of thoroughness, and was busy enough not to be able to start right away (some others were chomping at the bit to do it before the winter).

I am going to keep an eye on oil usage this winter, and also see how much I use the baseboard heat.

:sharebeer
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