Key Post: geothermal heating system/ground source heat pump

E

extopia

Guest
Anyone got any comments on the reliability/efficiencies of such a system, which allegedly uses the earth's natural heat to warm your house. Would especially like to hear from anyone who has installed such a system or knows someone who has.
Thanks
 
L

legend99

Guest
..

Isn't it so expensive for install that it takes more than 20 years or something to pay for itself?
 
E

extopia

Guest
Re: costs

I've heard that statistic.... but not sure that it means anything. Does an oil system EVER pay for itself? If it pays for itself at all well that's a positive. Am interested in being environmentally friendly and also not being dependent on oil. Gas is not an option where I am.
 
M

murray

Guest
heat-pump

Hi extopia,
We starting our build in the next 6 weeks and will be installing a geothermal heating system. We have researched this thoroughly and think that it only takes 3-5 years to pay for itself. With the rising price of oil and the fact that it will probably run out within the next 20-30 years, we figured it was worth the extra hassle and (initial) expense. If you are going to go down this route, it's probably worth factoring in extra insulation in order to maximise the efficiency of your system.
 
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extopia

Guest
Re: heat-pump

Murray, which system and company did you use? I'm looking at ClimateMaster.
 
H

heinbloed

Guest
prices for energy

As long as oil is the major energy source all other energy
prices will go up and down with the oil price.That is the principle of the free market.And night safer is only worth it - at the moment-since we have outdated energy plants.Once they are taken from the grit you have to pay for electricity what it costs.A taxi is not cheaper at night time.For example.And most of us -industry and private-need the warmth,the heat,during the day.So make sure that your financial calculations are based on economical realties and not on propaganda material.
For the environment it could be better to use a geothermal system-as long as you use no electricity to run it .At least no conventional electricity but "green"electricity which is more expensive.Think also about the Grey energy that is embedded in the product.A product that costs €5000 contains energy worth....€5000!Usually that is "cheap","dirty" energy,market forces usually enforce the usage of cheap
energy during the manufacturing process.Watch the company producing/selling/installing the product:D o they use "green" energy ?What sort of cars do they drive etc.?What happens to the profits that they make?A bigger company car for the Boss?An extra flight holiday for the sales man?An energy consuming equipment does NEVER pay for it self since it DEMANDS permanently energy.
The solution for this problem:an energy PRODUCING equipment ! Like for example solar energy,wind energy."Green" energy pays for itself (it will be a net earner once the installation costs have been covered),all other forms of energy production will always cost !Think logical.
 
E

extopia

Guest
Re: prices for energy

Interesting points, heinbloed.

But say I install a wind turbine on my land, that would produce more energy than I can use. It can't be a net earner unless I can sell the excess energy ("green" though it may be).

I doubt if I could ever justify the cost.

The Climatemaster system I'm looking at indeed uses electricity, as do most heating systems. But it uses no "direct" oil, and if one can believe the literature and the sales pitch, produces an additional 3 units of energy for each unit of purchased electrical energy. They claim that's 3 free units, but of course you pay for the system so nothing is actually free.

In choosing a heating system I'm looking for the following (in order of priority):

1. Comfort. I want the system to be capable of heating my house to an acceptable level for each member of my family.

2. Reliability. It has to keep working, especially in winter.

3. Cost-efficiency. I'm prepared to pay more now for a system that's more reliable in the long term, and that does not require constant "re-fills" (apart from the power element).

4. Eco-friendliness. If it fulfills the above and is better for the earth, great. I'll pay more than I would for an equally comfortable/reliable/cost-efficient but less environmentally friendly system, within limits.

I'm interested in your comment that a system that costs €5000 contains €5000 worth of energy. Do you mean that the profit element is necessarily used by the manufacturers to purchase "excess" energy, for example by driving bigger cars than you or I? How can one prove this kind of statement? It's a very interesting thought and I'd be interested in knowing more about your line of reasoning.

For what it's worth, I can't speak for the ClimateMaster operation because I haven't seen it, but the main distributor here, whose offices I have visited, is by no means a Flash Harry. Modest Industrial Estate warehouse building with one modest office and a couple of chairs for visitors. Nice people it has to be said.

Expensive system though, in the underfloor configuration I am interested in. Is it worth it? I reckon about twice the cost of a system based on an oil burner, but with lower ongoing costs. Haven't done the maths in any detailed way yet though. What else should I be considering? I'll be going with Poroton block construction in the extensions to my house, but the main building is 70-year-old rough stone construction, which needs total renovation.

Thanks for your thoughts, tell me more.
 
A

Arrowmania

Guest
Considering geothermal also!!

Great to see an informed discussion on this topic!!

I am currently building a house on my own land which will be the only house I will ever live in. I have been looking into the geothermal system as the main way of providing heat energy to run an underfloor heating system for my house. My feelings on it are that it seems like a great efficient system to run but the initial capital cost is scaring me a bit.

Different builders and plumbers who I have talked to about it have looked at me as if I had two heads and the usual comments are 'unproven', 'what if there is a leak', 'why not stick to the proven oil burner'. People in the general trade are extremely sceptical but then the same was probably true when people went from open fires as the main source of heat to an oil burner heating radiators. I myself think that the traditional oil fired burner could be on the way out as carbon taxes and other such measures are imposed on home-heating oil for use in burners which could be wildly inefficient and which can't be regulated or inspected.

Apart from the initial capital cost of a heat-pump I fully understand that, for the system to achieve payback on the initial capital cost, it needs to be efficient to run and this depends on making use of night-rate elecricity. Heinbloed's comments that night-rate could soon be a think of the past would have a major impact here and are very worrying.

I'll be watching this discussion with interest so keep the comments flowing!
 
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extopia

Guest
Re: Considering geothermal also!!

I would't worry too much about the comments of your builders and plumbers, who tend to be conservative about adopting new methods. Underfloor heating is widely used all over the globe, so it's hardly "unproven." It's just that it's relatively unusual here in Ireland. Your plumber knows how to fix leaks in a conventional system so that's what he wants to install.

Good question though, What if there IS a leak? I'd imagine its location would be fairly obvious in the concrete floor, part of which would then have to be taken up for the repair. Not TOO complicated but certainly harder than fixing an exposed pipe.
 
K

kfpg

Guest
Geothermal Discussion...Great !!!

Also delighted to see a discussion on this. I am building and have been researching this for ages. From what I can make out more and more companies are springing up and getting into heat pumps - there in itself is a danger. My research leads me to believe that this is a job where you go with the recognised experts in both geo and underfloor, companies who have been at this for a good number of years, have plenty of installations and are willing to give you phone numbers for happy customers (they all seem slow to respond in this area!!) There have been price discrepancies between all companies but I don't see an outlay of any less than €22k covering this installation.(my house is 2,800 sq ft)
Approx rough figures
Underfloor 8
Geothermal 10
Groundwork 1
Extras 1 (Kingspan insulation under pipes, other fittings etc)
Installation Cost 2 ???

It's obvious you have to be taking a long term view on this investment. Even though it is probably (??) cheaper to run, the payback I guess is 10 -15 years minimum. One concern here is that in 15 years time will the pump be either still working or as efficient as it is in the early years? Just when you think its pay back time perhaps there will be further investment required in the system.

I also believe that its wrong to focus too much on the heat pump itself to the exclusion of the devices and sensors which will "call" for heat to be sent to the floors / rooms. Spend as much attention on this i.e. individual zone (room) control, ideally digital stats with timers and temp control etc. Its as important for the system to stop calling for heat and the other way round. Example two downstairs rooms but only one sensor. Room A has high solar gain and heats up quickly due to large windows, room B is north facing with smaller window. Only one stat is calling for 19 degrees overall. By the time Room B reaches 19 it could be 22 degrees in Room A (underfloor on although room already warm) due to the heat not being able to shut off separately here. Answer = individual room zones and control.

Anyway back to the heat pump what we all really need are long term, happy users to contribute, they may well not be on Askaboutmoney?? Please keep the posts going as ye all find out more...
 
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extopia

Guest
Re: happy customers

Excellent point kfpg. I'll ask the salesman I've been dealing with for some customer references.
 
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harto1

Guest
Re: Geothermal heating system

Good post.

Am also planning a build and looking at heatpumps, mechanical ventilation and heat recovery, extra insulation, underfloor heating etc

I think the heat pump issue is set to become a hot topic in the coming 2-3 years. I have read recently that county councils and garda stations which are building new offices are using heat pumps. Now when public sector bodies who are often criticised as slow moving are adapting to new technology then I believe that points to a certain shift in thinking.

I believe the government should also be doing a lot more to encourage self builders as well as developers to go in this direction. There should be some form of grant aid and reduced or zero rated vat on the products, like in the uk and other european countries. I have also written an email on the subject to Minister Martin Cullen minister@environ.irlgov.ie . The response from the department was non-committal as you would expect, but did say to watch for future developments on the issue.

Although the technology is new here, it it tried and tested in many other countries around the world. It would be really interesting to have feedback from people using the system in Ireland.

On the electricity issue, if electricity does go up then don't forget standard boilers and heating systems use electricity too so they are affected. The oil companies use electricity, and will factor increases into their prices. Just think that as heatpump installations grow, particularly in rural areas, there will be less oil or gas delivery trucks frequenting the roads
reducing the risk of spillages and traffic pollution.
 
M

murray

Guest
geothermal heat pumps

Hi Extopia,
We have decided to go with a company in Cork called Alternative Heating and Cooling http://www.ahac.ie We recently visited a satisfied customer and grilled them about the company and the system for about 3 hours. I would highly recommend you do the same. This will also give you a much clearer picture as to how the system will work in your own house. Generally people (especially self-builds) are only too happy to show you around and talk about their house.
Good luck.
 
D

davelerave

Guest
heating

i'm on a job now where they're installing it,the pipe runs up and down the floor with about a foot spacing between loops.i'm sure they pressure test the initial installation work and i see them taking photographs of the pipe layout.i think there might be some sort of backup for the ground heat like an immersion heater type thing but i'm not sure ,i wasn't talking to them
 
H

heinbloed

Guest
geothermal heating pumps

I would be very interested to see some calculations on
a.) costs to run a heating pump,what are these costs
based on etc.
b.) the environmental costs,carbon dioxide , land use ,
etc.
c.) maintenance costs
d.) experience by a user
I myself use underfloor heating and I am happy with it.It takes much longer to heat up the room from zero but no problem with the right thermostats.And in combination with a condensing boiler it is not more expensive to run than a conventional rad. system.And with good insulation and sun facing windows it is cheaper to run.I use LPG and have a 1400l tank in use since June last year , still the first filling despite that it used for cooking and warm domestic water as well,10% still left in the tank.So more than a year heating ,warm water, cooking for €400.When I think of my old ,damp and cold semi
detached-what a difference!
So underfloor heating gets my thumbs up but I am still not convinced by the geothermal heating system.The SEI was not too convinced either,seeing the point of carbon dioxide emissions.Electricity from the Irish grid contains only 1% or 2% non-CO2 emitting prime energy.
Electricity is the must polluting form of energy use.So if there comes a carbon tax it will hit electricity prices hardest.On the web page of the SEI are some numbers available concerning CO2 emissions by various energy forms, see www.sei.ie
Keep posting, it is an interesting issue.
 
H

harto1

Guest
Re: geothermal heating pumps

This article also from the SEI makes for an interesting read.
It gives energy and co2 reductions calculations for different energy saving standards which could be applied to a house. So you can compare on a par the effects of passive solar gain, better heating system (condensing bolier), improved insulation, solar water heating, heat pump.

www.sei.ie/uploads/docume...ations.

The heat pump does not fair as well as the condensing bolier run on natural gas for example, but when compared with an oil powered boiler it achieves a considerable decrease of CO2 emmission.
 
H

heinbloed

Guest
geo-heating pump

Hi harto1!
The sei page gives no figures of cost comparing a geo-heating system with some other systems.The important number in such a calculation is the cost for electricity.Where is the break even point -€cents per usable kilowatt hour heating energy ? This number makes a financial calculation a genuine calculation.A pity that we don't have any numbers regarding that point.....And as far as I searched no trader of geothermal heating pumps gives out such a number.Geothermal heating is on the market on the continent since many years.But it never reached mass satisfaction i.e. only in certain cases -when heat is needed at night time(nightsafer) and when the system is used for cooling as well.The long pay-back times of 20 jears or so haven't made it possible to give a final result,if the night safer -or electricity prices in general -goes up than all the financial calculations have to be adjusted.
In my opinion a good insulation of the building makes a geothermal heating system surplus.The lesser the demand for energy the longer the payback time.And with a low energy house or a passive house the pay back time would be somewhere in eternity.
The money for a geothermal heating system is better invested in insulation.Energy that is not needed won't be payed for since it won't be consumed.Equipping a badly insulated building with an expensive heating system makes no sense no matter which system is used.
But I have an open mind for any figures and would welcome the posting of any of those.
 
G

glenamaddy

Guest
Re: geo-heating pump

heinbloed, what make, model and output boiler do you use?
 
K

kfpg

Guest
Geothermal Un-necessary in Well Insulated House

Heinbloed, thanks for your post, as always you make some great points. My situation leads me to think you would be cautious about the large investment in geothermal if you were in my position. As you recommend I plan to insulate my house well,

Wall Cavity Increased from 100mm to 125mm (4" to 5") to allow extra insulation.
Cavity to be fully pump filled with Polypearl beads.
Windows proposed considered to be the best available in terms of insulation quality, timber frame, double glaze, well sealed, gas filled K glass, low e (etc)
Large panes South facing for passive gain.
Smaller Panes for north facing windows.
Propose to use all insulation in loft etc with good K values
(not sure what else I can do)

Anyway from your post I take the point that a geothermal system in this house could have a 20 plus year payback which is not very attractive. I feel now that I might be well advised to look at a condensing type boiler to run in conjunction with underfloor heating. My question to you is if you have much knowledge of gas condensing versus oil condensing, which would be the best??
 
H

heinbloed

Guest
geo-heating pump

Hi glenamaddy !
For my underfloor heating I use a "vokera hydra" which is a modulating condensing combi boiler.It "modulates" the heating output automatically from a minimum of 8 kw up to a maximum of 26 kw depending on demand.These are the numbers for a flow temperature of 50 degrees Celsius and a return temperature of 30 degrees Celsius , taken from the installation and servicing instructions.Since I adjusted the flow to around 40 degrees -the return is about 5 degrees lower- it operates at its minimum output.The house is well insulated and floor heating does not demand higher temperatures.The efficiency is 90.3%, which means that 9.7% of the primary energy is lost as steam.
"Combi" means it produces hot tap water as well ,on demand , without the need for a holding tank.
The calculations I got from the underfloor heat. manufacturer rated the demand for heating at 8 kw.At the time there where no smaller boilers available,so my over sized model would produce enough output for two more houses."Vailant" and a few other manufacturers are producing smaller boilers but you have to check your self to get one in Ireland.Try Heatmerchants.For efficiency check www.sedbuk.com
 
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