Geothermal and UFH Vs Oil and Rads

MicktheMan

Plombier wrote: »

You said the house was 1900 sq ft(180 m sq) if the house is not up to current building regulations then I suspect that using a figure of 75 watts per meter sq. might be about right for this excercise, 180 msq times 75 is 12.6 KW just for heating, 12.6 times 24 is 304.4 KWH because of the current weather the heating system is at design condition and will run continuiously as would oil or gas, you measured 52.4 KWH of electricity for a 24 hr period giving 304.4 KWH of heat thats a COP of 5.8 which is excellent. Oil (approx 10KW/ltr.)for the same period with a 90% efficient boiler 10KWH times 90% is 9KW/ltr. 33.8 ltrs. per 24hr at the wonderful price of 55 cent will cost 18.60 for the same period but at 75 cent its 25.35.

HP____Oil@ 55c____ Oil@ 75c
€8.34__ €18.60_____€25.35

The cycles you see are related to different parts of the heatpump, compressor, heating pump, brine pump etc.

33.8 l/24hrs ... "A" rated 1900 sq ft house ...

Chipboard

No. It was stated to be an A rated house, but we've come to the conclusion that it's not.

Chipboard

RavenII wrote: »

At a third of the price of oil, its such a no-brainer; I think the title of this thread is stupid ....but you do have to run the things correctly and use a good heatpump.... Your bill won't be as high as you think, as I said before there's nothing else happening in the empty house...are the curtains even drawn in the evenings etc etc

I accept that if the house was occupied it may have a positive effect but it's doubtful. Surely the opening and closing of external doors would seriously lessen the heat retention. Your cooker fridge etc may produce heat but these use electricity too and surely a geothermal heat pump must be more efficicient producer of heat than a household appliance. If we're at home some night and it feels a bit cold I'm unlikely to ask my wife to boil the kettle! I'm going to say turn up the heating. I don't accept that the presence of 'people' would heat the house. Houses heat people not the other way around.

These systems may be viable in very well insulated houses but based on everything I've discovered to date, they are totally uneconomical in most houses. I was speaking to a builder last night who reckons that he knows loads of people who have them and they all have had huge electricity bills. As a result most are supplementing there use with solid fuel. That's proof enough for me. If you outlay the capital required for this system, you should never have to use solid fuel.

I've queried with the SEAI and will post up their response. It shouldn't be difficult to estimate the annual cost, given the cost for this time if year.

Chipboard

RavenII wrote: »

At a third of the price of oil, its such a no-brainer; I think the title of this thread is stupid ....but you do have to run the things correctly and use a good heatpump.... Your bill won't be as high as you think, as I said before there's nothing else happening in the empty house...are the curtains even drawn in the evenings etc etc

I accept that if the house was occupied it may have a positive effect but it's doubtful. Surely the opening and closing of external doors would seriously lessen the heat retention. Your cooker fridge etc may produce heat but these use electricity too and surely a geothermal heat pump must be more efficicient producer of heat than a household appliance. If we're at home some night and it feels a bit cold I'm unlikely to ask my wife to boil the kettle! I'm going to say turn up the heating. I don't accept that the presence of 'people' would heat the house. Houses heat people not the other way around.

These systems may be viable in very well insulated houses but based on everything I've discovered to date, they are totally uneconomical in most houses. I was speaking to a builder last night who reckons that he knows loads of people who have them and they all have had huge electricity bills. As a result most are supplementing there use with solid fuel. That's proof enough for me. If you outlay the capital required for this system, you should never have to use solid fuel.

I've queried with the SEAI and will post up their response. It shouldn't be difficult to estimate the annual cost, given the cost for this time if year.

RavenII

The fact that a building is occupied, means its picks up incidental heat from all the other normal electrical things in the building...I merely made the point because your 'test' isn't reflecting reality...I'm not saying you would boil a kettle to heat the house

People with heatpumps have higher electricity bills...of course!..they can't run them for free..but they SPEND LESS MONEY overall, and that I assume is what you're worried about. The eejits bob-the-builder etc is talking to are forgetting they HAVE NO OIL BILL, so you're getting bad info there!

If a house is badly insulated, then it will need more energy - that will cost you more on oil, simple, easily proven fact. Just read SEAI's bi-monthly 'Domestic Fuel Cost comparison' charts on their site.

To sum up, I paid about €1400 odd extra on electricity (this year), the SAME energy on oil would have been €3500 + (we used to use 4 x fills of oil a year and turned the heating on & off - now we just leave it on). I'm happy!

P.S. People are warmer than the air surrounding them....if you ask enough friends around....An average person adds around 70W of heat energy to a zone, just by being there. (Wikipedia)

L driver

Hello,
Raven/Evarybody in a very well insulated house would the capital costs of a heatpump make an oil condensing boiler with UFH more attractive?An oil boiler approx €1400 versus ASHP €7000 ( I think), GSHP €????. I know it satisfies the renewable part of planning, but I think we should be using solar regardless.
I am only asking the Q, and my figures are open to interrogation. But alot of oil could be bought for the difference and in a very well insulated house there would be no need for heating up the floor on night saver. I like the idea of a heatpump and I know people that will show esb bills and they are as you say. I also know people and their HP is a disaster but so is their insulation and maybe there installer was too.
Anyway back to the original question in a very well insulated house would the capital costs of a heatpump make an oil condensing boiler with UFH more attractive?

Chipboard

RavenII wrote: »

To sum up, I paid about €1400 odd extra on electricity (this year), the SAME energy on oil would have been €3500 + (we used to use 4 x fills of oil a year and turned the heating on & off - now we just leave it on). I'm happy!

With due respect my test is nearer to reality than your example. We currently rent a house which is ridiculously badly insulated and we still only use 2.5 tanks (1000 ltrs per tank) per year and our house is occupied 24/7/365. How the hell could you use €3500 a year with intermittent use. Methinks that like alot of people you would say black was white to justify geothermal and ufh.

I am taking account of the fact that I won't have oil bills if I buy this house. At the moment it still doesn't look viable. 53 kw of electricity per day or 3200 per two monthly bill is alot no matter what way you carve it up. If the SEAI are able to give me a rough distribution of heating costs over the year I will know more.

RavenII

[ How the hell could you use €3500 a year with intermittent use. Methinks that like alot of people you would say black was white to justify geothermal and ufh.


LOL! ...I'll tell you how: -

1. My wife loves heat, but she does suffer from bad arthritis
2. The house is 3500 Sq. Ft and very tall ceilings, roughly 20" in one area and a lot of open plan areas.
3. Built in 1971, 2/3 of the house has just 25mm of insulation in the walls.

We used to consume 4 x 1200L fill annually...I don't need to 'justify' our choice of heating, it has paid for itself by now. Getting €6500 from SEI was nice too.

RavenII

L driver wrote: »

Hello,
Raven/Evarybody in a very well insulated house would the capital costs of a heatpump make an oil condensing boiler with UFH more attractive?QUOTE]

Think it would depend on whether its a new build or retrofit....

If its a new house, I'd go for a geothermal heatpump (with the hot water built-in) and locate it in your utility room. Then you are looking at the difference in cost for that over oil boiler/cylinder/controls/oil-tank etc. If it was just the OFCH vs Geo contest then the difference may be somehwere around €4000, but if you have to comply with new regs and fit solar with the oil, you'll probably have spent just as much on the install but will not have a system that is as cheap to run. Two solar panels will save about 3000kW hrs a year, if those kWs are from burning oil, that's about €300. (10.3c per kW according to SEAI)

Read a few posts back too, it was dealt with already I think.

L driver

Hello,
Please forward me name of company that is only €4000 dearer with geo than oil,
Thanks in advance

parkman2010

Hi folks,
Apologies for the long post.
Just reading all the posts here with interest. I'm currently in my new home built in 2008/2009. I have a Neura heatpump installed, and have had nothing but trouble with it. This is my second winter in my new home and my second winter without heating, thanks to my interest in doing what I see as the right thing and being "green". These systems can work very well, but unfortunately there are alot of installers out there that don't know what they are doing. I am now starting to really regret spending big bucks for a cold house.

L driver

Parkman,
sorry to hear your woes. How much did your heatpump cost? Is it installed badly?

parkman2010

It was included in all the plumbing, all in all about 26k. I guess that the heatpump itself must be around 15k. Too much for something that doesn't work in the winter, when you need it most.
Don't know if it is the installation or the unit is faulty. Still waiting on answers!

L driver

parkman2010 wrote: »

It was included in all the plumbing, all in all about 26k. I guess that the heatpump itself must be around 15k. Too much for something that doesn't work in the winter, when you need it most.
Don't know if it is the installation or the unit is faulty. Still waiting on answers!

Best of luck. Keep us updated please. It seems to me that the installer might be a huge factor in relation to heatpumps, because it is the constant in the scenarios. What is the formal training for a heatpump installer/engineer?

Chipboard

RavenII wrote: »

Built in 1971, 2/3 of the house has just 25mm of insulaWe used to consume 4 x 1200L fill annually...I don't need to 'justify' our choice of heating, it has paid for itself by now. Getting €6500 from SEI was nice too.

I don't believe that you went from spending €3500 on oil annually to an annual ESB for geothermal of €1400 unless you spent a very significant amount on insulation - which of course would have significantly reduced your Oil bill. GHP is not economical in a badly insulated house.

If someone can afford it and they want to have geothermal, fine, but unless the payback period is reasonable, it is a waste of money.

There was a programme on rte two weeks ago about a guy who built a passive house. He put in a domestic wind turbine (total White elephant) which he said had a payback period of 26 years. In reality this means it won't pay for itself at all, as it will be sitting in a junkyard in less than 15.

RavenII

L driver wrote: »

Hello,
Please forward me name of company that is only €4000 dearer with geo than oil,
Thanks in advance

Ken Glover installed ours - 087 8296762 - very competent, really knows his heatpumps.

RavenII

Chipboard wrote: »

I don't believe that you went from spending €3500 on oil annually to an annual ESB for geothermal of €1400 unless you spent a very significant amount on insulation .

Well as I said, we used to get an average of 4 fills a year, 1000 to 1200L a pop. That was our hot water too in summer. We didn't add in any significant insulation, we extended the building a little too, so just the extension is well insulated. It is a fairly large house too.

The cost meter squares with the heatpump's current read-out, so we believe it to be quite accurate.

In an existing house, if you know how much oil you use, its easy to convert that to an annual energy total and work out the payback of the heatpump installation...thats a calculation you should ask you installer for.

weston1

hi raven, where is ken glover based, is he a plumber on his own or is he with one of the geothermal companies

weston1

hi raven again. got quotes off a number of geothermal co.s both for air to water and ground collecter. there is some variance in the quotes for what looks like the same product from different companies. eg. one co wanted nearly 13k for uf pipes supply and install another wanted only 3380 plus vat. quotes ranging from 17k to 37k depending on the company. its nothing to do with the air system or ground collecter as individaul companys only have a 10 to 15 % variance between them on their quotes

RavenII

Ken's in Wicklow, near Redcross, works for himself with a couple of guys. He's actually an electrician but with a plumbing background...that's probably why his controls etc work!

Plumbers often treat heatpumps like they're boilers, they need to be piped and set up slightly differently, which probably accounts for a lot of the whingeing here!

parkman2010

yes will keep ye posted Ldriver, just found out that the company installing them has gone bust but they have told me that they are still going to service the units they installed. I think it might be worth getting on to the manufacturer at this stage and finding out if they are going to deal with it directly. As for the formal training of installers, i'm not really sure if there is any. Like everything in this country, if you pay some tax no one will ask any questions!

Jrochey

Well lads just wondering given the current weather conditions and extreme frost and cold how do people who have a geo system currently rate their system. Got a quote for 13500 for a 13kw heat pump and 8500 for underfloor on both floors in a 2960sq ft house horizontal loop in the garden thats inclusive of vat and labour what do ya reckon good/bad. Should the quotes be lower given current economic conditions. Have been told that a normal heating oil based system would be half the price without including solar panels which would bring it up to 20grand true or not any advice would be greatly appreciated thanks

parkman2010

Jrochey wrote: »

Well lads just wondering given the current weather conditions and extreme frost and cold how do people who have a geo system currently rate their system. Got a quote for 13500 for a 13kw heat pump and 8500 for underfloor on both floors in a 2960sq ft house horizontal loop in the garden thats inclusive of vat and labour what do ya reckon good/bad. Should the quotes be lower given current economic conditions. Have been told that a normal heating oil based system would be half the price without including solar panels which would bring it up to 20grand true or not any advice would be greatly appreciated thanks

Hi Jrochey,
See my post above about my current situation. Don't allow this to put you off going ahead with your geothermal system. When it works right it is a dream, the problem is getting the right installer to put it in for you. As regards your prices that you refer to above, they sound ok given the fact that competition is strong at the moment in the market. Make sure you go and visit some houses that have the system installed by the company you are thinking of using. Also have you considered getting some form of backup system in case of problems with the unit? Possibly connecting a solid fuel stove? Consider what are the effects of the unit failing? What backup service is given, warranties etc. Consider the cost saving versus oil. Worth checking www.sei.ie website. Hope this helps you to make up your mind!!

Jrochey

Hi Parkman,
Thanks for the response. I was thinking of getting a buffer tank and piping a solid fuel stove into it in case the esb prices rose etc he included all the pipework from the stove to the dhw tank and plate exchanger. 13kw he reckons it will keep costs down. Hard to know what to do !! reckon i'd need 20 rads or so otherwise with back boiler and solar panels have u good insulation and good windows is that helping. Having a disaster on ur hands is not what i want bills are hard enough to pay without extra hassle. Given the bord gais intro to the market do u think it might help bring down prices.

parkman2010

Hi Jrochey,
Yeah I think that you have a good idea in the stove. I did the same myself, I connected up a 14Kw stove straight to the tank. My tank has the top half for hot water and below for the heating system. The mistake I seem to have made is that the hot water from the stove is piping into the hot water area of the tank. This in turn is supposed to heat the buffer area. It does not. The basic result I have now is that the stove brings the tank to 70 deg +, but when I turn on the ufh pump it has only access to about 30deg. And this only lasts for about 1 hour before you are back to 20deg or less. Therfore it is pointless for the ufh. I am putting in a new tank without the buffer system in the future to see if this works.
As regards the windows, they are double glazed but to be honest I would put in triple if I had the chance again. Insulation is pretty good, as I did it myself!! or at least I hope its good enough.

I am actually with airtricity and yes it does make a big difference!!

Just wondering where abouts in the country are ya?

Plombier

parkman2010 I think by your description that you will only need to change pipework and controls, you shouldn't need to change the tank.

Idbatterim

can you not get gas? you could get a condensing combi boiler, even one with a heat exchange on it, they are extremely efficient, and only heat up water when you open the tap and provide unlimited amounts.

Arseways

Underfloor or rads? Depends what you're looking for. Underfloor heating provides a very comfortable environment, at a cost. It has a very slow thermal response, ie it takes time to heat it's environment, and for this reason it's recommended that the underfloor heating be left on 24/7. Therefore it uses fuel to maintain an ambient room temp of approx 20c for 24 hrs per day. Rads on the other hand have a fast thermal response and need only use fuel to maintain an ambient room temp of 20c for the time of occupancy..........8 hrs per day!? For this reason, as comfortable as it is, underfloor heating is more expensive to run, regardless of the fuel or heat source.

You'd also have to ask yourself, with our changeable weather, would a heating system with a fast or slow thermal response be more sensible??

kingchess

hi all,my house is 2500 square foot and my esb bills for 08 was around 1670 and for 09 it was 1600 euro,(with airtricity this year so cheaper,)this includes every thing for the house-cooker fridge etc and all heating and hot water,my hp is a thermia diplomat 10 and has a built in 180lt tank,it also has an immersion built in but i never connected that up, ihave ufh down stairs and rads upstairs that i never use.also a stove and a fireplace that i never light as there is no need.i put in the ufh pipes myself cost around 800 euro all leading to the utility room where hp is.150mm insulation under the 75 mm screed,used quinnlite block for inner leaf of house and put 200 mm insulation in the attic.moved in just before youngest was born in jan 08 +two older girls and they all love leaving lights etc on.i bought my hp from poland around 6000 euro deliverd to my door in late 07 and got grant of 4500.my own plumber connected it up, there is 450m of collector pipe buried in the field-cant remenber the cost of that but i paid 300 euro for the gysol(antifreeze) to put in that and 300 to digger man, if it cost me more than 5000 including the grant i would be suprised. i think the bottom line is insulate and then insulate some more

jimmyging

hi all,

we have a new build and had nuera ghp with ufh installed when we moved in last year.the whole system was running v well and our esb bills were €1900 for last year for a 3800 sq ft house and plenty of hot water .I am now sitting in the kitchen with 2 dimplexes on and the stove blazing as our compressor is gone I believe.I have been told that it will take 2 weeks to get this compressor in from Austria so on with the thermals for the moment.Anyone have this happen to them?