Low utility bills with geothermal heat

[JackMentink]

I know everybody is into the alternative building types and high tech insulation sytems, but most I've seen are not real cost effective and have very long paybacks.

When I built our new house two years a go I went with 6" stud walls, r-19 blown in cellulose, r-48 blown in celulose in the ceiling, and anderson 200 series low-e windows (lots of them as my wife is a sunshine fanatic. I paid attention to the house wrap to get it sealed on the outside, and put my energies in the heating system.

I installed a ground source heat pump with a open loop system that use my well that supplies water to the home to supply a geothermal source. ( I upsized the well pump to a 2 HP and put a variable speed drive on the pump).

I discharge the geothermal water into two 1500 gallon tanks that I use to irrigate my two acre lawn. The heat pump has a variable speed fan and four zones with four thermostats to keep the house perfectly temperate in all areas. The house is the most comfortable I have ever been in it cost less than conventional system as my electric cooperative gave me a $1700 rebate for the system.

The house is 4400 square feet finished with all of it heated and cooled to 73 year round.
It is about 2800 foot ranch over a full walk out basement. I live in Missouri and we have winter with lows of 0 and summers over 95 for weeks.

The best part is the utility bills. The largest heating portion of the electric bill we have ever had was $45/month, with the largest summer cooling bill of $30/month.

Ground source heat pumps rock

 

[BruceWard]

Great info. I am curious what brand of ground source heat pump are you using?

Also do you know how much water you are pumping out the ground?

I am planning for a closed loop system on a house we are building next year.

 

[JackMentink]

My unit is a Water furnace. As far as how much water it depends on how much the furnace runs. At 3 tons it uses 6 gallons per minute, at 6 tons it uses 12 gallons per minute. On a day where it doesn't run a lot it uses 700 gallons in a day. On a real hot or very cold day it uses about 3000 gallons of water in a day.

Water is very economical to pump, and we have very strong aquifers in this area of Missouri

 

[woodlandfarms]

I am thinking of closed loop as well. What do you do with the remainder of the water? Once pumped I would think they would not allow it to return to down the wellhead.

Also, are you using this system for cooling, like a swamp cooler? Just wondering how the cooling works out for you.

Also, how deep is your well? The water is 55 degrees or are you getting something different?

 

[peterssj4034]

I have a closed loop, vertical geothermal system using 2, two stage electric heat pumps that heat and cool about 5,000 square feet. I live in Northeast Ohio, so our summers aren't quite as hot, and our winters can be a bit colder (we had numerous days of below zero temps this year). I have an all electric house, built in 2006. My electric bill, for everything, is between $100 (spring/fall) and $225 (coldest months, Jan/Feb).

I have already recouped the additional cost of installing this system in the short time I have lived in my house.

Seth

 

[eepete]

My heat pumps (two 3 ton, one 5 ton) are also Water Furnace. They are closed loop systems with horizontal ground loops. House is insulated with 5" isocyonate (sp?) foam in walls, 7" in ceiling. Tin roof reflects lots of heat. The entire house is enclosed space so the attic is sealed too. Way to expensive 2 pane Anderson argon filed low E windows. Fenestration percentage is about 13.5% with the main room (kitchen/living room) area pushing that up there, most of the other rooms are single window or small windows. We also upped the air duct sizes by 2" over what was recommended for better efficiency and increased the number of output registers in bedrooms so that the noise level was reduced. I could drone on about many other little tweaks that were done.

All of these various energy related things have about an 8 year payback on them. That's all a calculation, so could be 6 to 10. And when electric rates go up it gets better. A common theme dealing with all the energy related trades is that they push things with 3 year paybacks because that's all most people will pay for. This is also what they have been taught. So you really have to fight to spend more money. Since I'm leaving here horizontally some day, a long payback period and doing it right were doable. A starter house is a much more challenging problem, but you can make good decisions and get most of the money back by showing off your low electric bill. Nothing new here- If you're in your 40's or higher, I'll bet your 2nd or 3rd tractor was bigger and cost more than your 1st tractor.

Interesting money numbers example: We did semi-custom cabinets and Corian counter tops. That saved about $35K over full custom cabinets and granite counter tops. That money paid for all the improvements in energy related areas. Much like life, I worry more about feeling good on the inside than looking good on the outside, but then I'm just a butt ugly geek.

Pete

 

[JackMentink]

I am thinking of closed loop as well. What do you do with the remainder of the water? Once pumped I would think they would not allow it to return to down the wellhead.

Also, are you using this system for cooling, like a swamp cooler? Just wondering how the cooling works out for you.

Also, how deep is your well? The water is 55 degrees or are you getting something different?

As fAR as my system goes the excess water that is placed on my yard just overflowes my irrigation tanks and down a swale on the back of my property.

I use the system for cooling but the water is just what is circulated over my coils , the same way as an Air to Air heat pump does with air cooling the coils. Mine just uses 55-57 degree water as my fluid instead of air. Stiill a totally sealed system with freon.

My well is about 370 feet deep with the pump set at about 220' and my sttic water level is about at 100'

The nice thing is that my unit has a zero year pay back. I priced high effeicency gas heat with high efficiency cooling and it was the same price as my ground source unit. I had to up size my well (2 hp) and put a variable frequency drive on the pump and all that cost about $2000 extra, but I got a $1700 rebate from my cooperative for installing the ground source heat pump.

So it started paying for itself from day one. I estimate that it saves me about 2000-2500 per year at todays electric prices (7 cent a KW). That will increase as time goes on. The other thing is that the blower on the furnace is on a variable freq drive so it slowly ramps up and down and only speeds up to the speed it needs. It also has a loop that pre heats my hot water when it is in cooling mode.

I have to say that the house is the most comfortable, even, draft free home we have ever lived in. And it is economical also.

Geothermal Heat pump is the way to go.

 

[woodlandfarms]

Given the politics of washington state, I am sure that they would not allow open loop. In a state that rains so much, the water seems pretty precious (I don't mind as I am a bit of a tree hugger).

Carl

 

[slan]

Most states either have or WILL be banning open loop systems and for GOOD reason if you think about it.
IMHO

I have a closed loop system in my lake. If my neighbor was pumping water out of OUR water source I would be having a talk with him directly but I would,t need to because it is illegal to do it here.
Sorry, not a tree hugger but you got to think about what your doing as fresh water will be like oil in another 20 years.
Geothermo systems are great, I just dont like anyone promoting the open loop system because they are cheaper.

 

[dave1949]

Most states either have or WILL be banning open loop systems and for GOOD reason if you think about it.
IMHO.

Like a 100 house subdivision each with open loop geothermal? That would be problematic.
Dave.