Geo Theromal Heating

Wobs

Hi Slayer,

How big is your house? I got a quote from Sweco for the aerothermal and it was 15000 yo yo's. The house is 2800 sq ft. They reckoned id need 2 units @ 7500 each.

yop

Thanks lads for getting back, Slayer what sort of sponds are you talking?

Wobs- Are you happy with the Aerothermal? I have been doing a lot of research there over the last few weeks and without a doubt the D/X Geo is more efficent, but if you do not have the ground then you are grand.

Of interest more links!

http://geoheat.oit.edu/ghp/survival.pdf
http://geoheat.oit.edu/ghp/ghptable.htm

Also I was talking to a few people who have done papers on the different types, one is a Dr in the Dept of Geology of a Uni in Ireland and he said as regards the ground losing heat, something that the Aerothermal lads are claiming

The 1m cover of soil provides insulation, and temperature at that depth will not fluctuate to any extent. Air temperature is much more subject to fluctuation than the ground.

I also talked to a number of peole who are heavily involved in Alternative energy in the US, I asked him what he thought of both.

Air Source:
An air source heat pump removes heat from the outside air in the winter months and delivers heat to the outside air in the summer months. In the winter as the outside air temperature drops, the heat pump becomes less efficient down to 3 celsius. At this temperature a backup heating system must be activated to keep the home warm. When the outdoor temperatures are at their extremes the air source heat pump becomes less efficient in both heating and cooling. Also air temperatures can vary many degrees during day and night time and heat pump compressors do not like these drastic temperature changes. Result is that the life of the compressor is reduced.
Ground Source:
The ground source heat pump sees uniform earth temperatures year round because the earth temperature is more consistant than the outside air temperature. Yes it is true that at the end of the heating season the ground temperature could drop if it is an extremely long cold winter. The main difference is that the ground source heat pump will heat the home down to -15 degrees celsius befroe you need auxillary backup heat.
The earth loops can be installed vertically; diagonally or horizontal outside. The cost of installing a ground source heat pump is more than an air source heat pump but the benefits are much better. The horizontal system is buried (2) meters below the earth surface. The verticle bores are (15) meters deep.

just out of Interest lads how many have gone with Sweco based on getting the information from boards, I might get them to do us a promotional discount since from what I can see there are definately 4 of us who will be going with Sweco based on the information from here??


More info
http://www.nordicghp.com/mg/hpworks.htm
http://www.greenbuilder.com/sourcebook/groundsource/groundsourceeffic.html
http://www.spiritofmaat.com/archive/apr2/heatpump.htm
http://oee.nrcan.gc.ca/publications/infosource/pub/home/Heating_and_Cooling_with_a_Heat_Pump_Section3.cfm

Wobs

Yop

Won't be going with the aero, its a bit pricey and you have two big fans on the side of your house. I think I'll be going with the geo (Nibe) and ufh from unipipe, not the cheapest but from my dealings with them they seem very professional and their products are good. Also I have heard good feed back from other people in the building industry about them, regards reliability etc.

Asked Sweco yo quote for D/X but only quoted for the Aero. They are really trying to push it hard!!!

yop

Without a doubt they are pushing the Aero, too much so, reason is that it seems to be, from what I have been told, more expensive to purchase, with a bigger profit from them.

yop

Another update lads on another system I visited the last day. I have decided that after loads of web searching and reading papers published etc, that the Direct Evaportation (DX) system is far more efficent than a standard GSHP or ASHP.
So I did a bit more googling and I came across another company that are doing the DX system in Ireland apart from SWECO. They are CLimate Control in Galway, I contacted the lads there and luckily for me they are just after installing a GSHP in Mayo.
SO I took a trip to it there on Thursday evening, again you are talking a pump unit, about 2ft square by 4ft high. They supply Heliotherm pumps in Ireland and to be honest it is the sleekest pumps I have seen around, and good set of menus to control
the pump, heating phases, temperatures and also control your UFH which negates the needs for thermostats on your UFH, they reckon that in real terms a person rarely changes the UFH thermostats in each room and the fact that there is a temperature sensor outside that adjusts the heat according to the weather then this will cover the lack of themostats in the house, not convinced on this issue though.
The one this about this pump that I like is its usage calculating and logging so that you can see how much electricity you are using, also a modem allows them to fine tune the heatpump and diagnose issues, a fancy feature admittedly but sure we will see what happens!
Also the COP of this pump is the highest I have found at 5.7, meaning that for every 1KW of electricity it uses it produces 5.7.
In the house I was in the last day for the month that they HP was on, if you were to muliple the cost of electricity for that month by 12 it was working out at 326 euro for the year, but March was not really a cold month.

So at the minute these guys are the front runners, the cost of the system is higher than the brine system quotes I have but I will have to work out the difference on the COP and the fact that this system has only 2 pumps as opposed to 4 on the older systems.

Doper Than U

Sounds brilliant Yop, €326 for the year? That's excellent. How much electricity is that in all (approx)? Just wondering if off grid is an option with this kind of system.

yop

Doper,
Hard to know, That €326 I would be sceptical off to be honest, March was mild BUT in saying that the COP is 2.6 higher than the brine system that Dunstar are selling and my first choice for a GSHP intially, they told me we were looking at about 600 euro odd to run the house for the year.

In fairness to them they have answered all my questions well, the fact they are only about 40 minute drive from me also gives them an advantage.
Still waiting for SWECO to come back to me though.

Robyn

slayer92 wrote:

Yop,
You check out the aerothermal option from Sweco. I am getting one installed in my house (2700) with U/F downstairs and rad upstairs. It is a 11kw heatpump run by a 2 kw electrical motor. The buffer tank is 500 litres and supplies the water for the heating system. The water for the domestic system (showers and taps) passes through the tank and is heated by the water for the heating system. This means the hot domestic water can be pressurised.
No costly excavations!!

Regards

slayer

Hi Slayer,

New to boards.ie - I was wondering if you have gone ahead with the Sweco aerothermal system ... and if so how did it go? Would you recommend it ?

Robyn.

yop

I got my quote for the aerothermal unit from SWECO, came in at just under 13k.

slayer92

Sorry about the delay in getting back to you.

4 of us from work did a deal with SWECO. It was agreed in late summer 2004. Each of us went for the Sweco 11 (10.3kw heat output) It supplies a 500l tank which acts as a source for the underfloor heating (downstairs) and rads(upstairs) The domestic hotwater passes through this tank and picks up heat from the tank water.
At the moment, I dont have it installed because the house is not ready for it yet, but one of the other lads has it installed last October. He is very happy with his system, had some problems with the gas pressure tripping the system and also so problems with ice forming on the fan coils, however after some teaks from Sweco all is sorted. His most serious problem was the fact that the domestic hot water was too hot at the taps!!!.
Regarding prices, I can't honesty tell you what we paid as we agree with Sweco on confidentality. Suffice to say it was under €10k. For the running costs, we monitored this closely over the winter(Oct to March), it worked at €3.50 per day at the worst of the winter to just under €1 at the moment.

Hope this helps
slayer92

Robyn

slayer92 wrote:

Sorry about the delay in getting back to you.

4 of us from work did a deal with SWECO. It was agreed in late summer 2004. Each of us went for the Sweco 11 (10.3kw heat output) It supplies a 500l tank which acts as a source for the underfloor heating (downstairs) and rads(upstairs) The domestic hotwater passes through this tank and picks up heat from the tank water.
At the moment, I dont have it installed because the house is not ready for it yet, but one of the other lads has it installed last October. He is very happy with his system, had some problems with the gas pressure tripping the system and also so problems with ice forming on the fan coils, however after some teaks from Sweco all is sorted. His most serious problem was the fact that the domestic hot water was too hot at the taps!!!.
Regarding prices, I can't honesty tell you what we paid as we agree with Sweco on confidentality. Suffice to say it was under €10k. For the running costs, we monitored this closely over the winter(Oct to March), it worked at €3.50 per day at the worst of the winter to just under €1 at the moment.

Hope this helps
slayer92

Thanks Slayer - that is encouraging - I had heard from someone else that the system hadn't settled and that the running costs were a lot higher than that because of the booster immersions. Do you know roughly the sq. footage of your friend's house ?

Thanks again,

Robyn.

yop

booster immersions.

I did not think there was any booster immersions on this system?

UNEDO

YOP,
Like you I am researching options on Mayo build.Research and investigations not nearly as detailed as yours. Had made contact with Climate Control through SEI listing and had also visited installation in Mayo. Price, COP, design of UFH system all seem in their favour. Very interested to see that you were leaning towards them- same as that for me.

Collector bed installation cost will include supply of sand bed for collector loop. Not yet sure of what the actual cost will be.

Issue of thremostats came up but it was beyond me so I had asked architect to have conversation with Climate control. Will post if I learn anything that might be of interest.

Understood that ideally I needed ground conditions which retained water. Thats not really true of my site but Climate Control have been very re-assuring that my site is suitable. Any comment.

[

yop

cost will include supply of sand bed for collector

Umm, mine did not now, I will have to get back to them!

Issue of thremostats came up but it was beyond me so I had asked architect to have conversation with Climate control. Will post if I learn anything that might be of interest.

Ya I think I might put mine into the bedrooms anyway, prefer to look and see "oh don't really use them" than "Oh I really should have installed them"

Understood that ideally I needed ground conditions which retained water. Thats not really true of my site but Climate Control have been very re-assuring that my site is suitable. Any comment.

I did not have a site visit yet, is it rocky dry ground you have??



Who is doing your UFH?





Where are you building, what size hut?

UNEDO wrote:

YOP,
Like you I am researching options on Mayo build.Research and investigations not nearly as detailed as yours. Had made contact with Climate Control through SEI listing and had also visited installation in Mayo. Price, COP, design of UFH system all seem in their favour. Very interested to see that you were leaning towards them- same as that for me.

Collector bed installation cost will include supply of sand bed for collector loop. Not yet sure of what the actual cost will be.

Issue of thremostats came up but it was beyond me so I had asked architect to have conversation with Climate control. Will post if I learn anything that might be of interest.

Understood that ideally I needed ground conditions which retained water. Thats not really true of my site but Climate Control have been very re-assuring that my site is suitable. Any comment.

[

UNEDO

YOP,
"Hut" is approx 1600 sq ft on gravel/sandy subsoil setting. The site has excellent drainage. No rock bed but does have large stone/boulder mixed with the gravelly subsoil

Have had reasonably competitve quote for UFH from Climate Control .


Current understanding with thermostats is that one is best not using them because the heatpump size will have been determined by the output necessary to service the entire building at a uniform temperature and Eliminating some of the spaces would lead to more on/offs for the system . this apparently can have a bearing on the working life of the heatpump.

UNEDO

yop

Your soil content is exactly same as ours!

Was the site visit in Balla by any chance??

Cleared the site now, will be putting in Raft next week so all moving along nicely

UNEDO

[!

Was the site visit in Balla by any chance??

Yes.

yop

ummm, do they have any other sites, I know of a number of people who have contacted them, all have been directed to Balla!

I would like to visit another of their sites

Bill2

On a kind-of related subject, could a domestic wind turbine like the ones sold by Surface Power be used to power a Geo Thermal heating system and drastically cut down the running costs or do these systems need additional power requirements that i'm now aware of. Are they just plug in systems..??

Thanks..

yop

I presume you mean used to power the heatpump?
I am sure they could, but I doubt the fact that the fluctuations in power would be great for the HP

Doper Than U

What if you used wind energy with batteries (instead of grid tied)? You'd plug the hp into the batteries, which would give a steady feed instead of fluctuating. How much power/electricty do you need to run the HP?

Also, would it run with solar?

shanea

Powering the heat pump from a battery system would cost more to install than what would ever be revovered in savings.

With electricity generated by wind, voltage and frequency regulation is a major pain in the butt.

Instead generate hot water by imersions directly and the need for the heat pump is reduced but it will be unlikely that it would be replaced.

Bill2

Has anybody sourced info on an alternative system to Geo Thermal like a heat recovery ventilation system with air ducts in each room somewhat like an airconditioning system.. I'd be interested in hearing from anyone who has a system like this and what their experiences have been..

Great thread, very informative for folks like me with no knowledge of the subject..

Doper Than U

Powering the heat pump from a battery system would cost more to install than what would ever be revovered in savings.

It's not so much the savings as it is the ability to be off grid. Also, we do plan to have wind power with batteries for other electricity needs, so it's not just this. I'm just wondering how much electricity the HP actually needs to run so I can calculate how much power I need to generate.

Wobs

Hi Bill2,

From what Ive gathered HRV units are not used as stand alone heating systems but more as a back up. The main use for them is ventilation, where a house is tightly sealed and you don't want to break the seal by putting vents in the walls. The heating element of them is so that the fresh air coming back into the house is at the same temp as the air that has gone out and thus not making the house temp drop.

From what i've heard they work well and are really good for people with allergies or asthma.

Wobs

Hey,

Saw this crowd in Construct Ireland magazine, www.sunstreamenergy.ie. They are only a new company but they are supplying Heliotherm heatpumps, they do the whole range DX, Brine, aero. They got a good right up and the pump looks the biz. I was talking to the guy yesterday and will be sending my plans, will let you know how I get on. 15kw DX with 500L tank and extra water heating option a few other things he told me about for 13.5 yoyo's approx. Sounds like a good system.

Only a new company so references may be hard to come by.

Yop as the resident boards expert on geo maybe you could check these guys out and let us know what you think.

*apologies if they have already been mentioned, but this thread is gettting a bit long to trawl through to see*

Cheers

yop

Wobs - Ya no problem, leave it with me.

I will have a look at these guys, what I find really interesting is the fact that ClimateControl told me that they are "exclusive distributors of Heliotherm and Gabotherm UFH"?????

"I'll be back"

shanea

Doper Than U wrote:

I'm just wondering how much electricity the HP actually needs to run so I can calculate how much power I need to generate.

A typical house would have a 12Kw output heat pump which would have a 60 amp (at least starting current) and a continous 10 to 20 amp running amperage (amps are temperature dependant, the higher the temperature the higher the amps and therefore the lower the efficiency).

A soft starter would help with the satrting load, can you supply 15 amps continous for 10 to 12 hours. OR a 6 Kw heat pump for 24 hrs @ 7amps????

boidey

what about using something like www.windsave.com

Nordic

Nordic here.
FYI...We do:
Water-to-Water (underfloor units and radiator units)
Water-to-Air
DX-to-water
DX-to-Air
Pool Conditioners (heat recovery)

The Water source units are available for numberous water sources:
Wells
Ground loops
Streams & Rivers
Sea-water
Milking parlours

We are now also offering Solar panels and wind turbines to existing or new customers at low prices for example:
2kW turbine (complete with 8m mast, inverter,etc) for Eur2,700 + VAT
20 vacuum tube solar panels for Eur1,400 + VAT

Don't always have time to check out forums so e-mail me info@nordic-geothermal.com with any queries.