Browse Forums Heating, Cooling & Insulation 1 Apr 17, 2010 9:10 pm Nice little piece in today's Age newspaper about geothermal heating/cooling Anyone use it? Anyone got any idea of approximate costs for this? Hmmm - methinks it can't be cheap Building on an acre in Macedon ......one day. Re: Geothermal ..... costs? 2Apr 17, 2010 11:04 pm Here is an article by the ATA: Geothermal 4 times the capital cost. About 1/2 running cost of an air-source heat pump (RCAC). The question is whether it will last long enough to pay for itself in savings. Re: Geothermal ..... costs? 3Apr 18, 2010 8:50 am Will also check this, interesting VICTORY 1800, EN-SUITE, DOUBLE GARAGE, FAMILY ROOM AND ALFRESCO Land Settled: 20 July 2010 Site Scrap: 30 August 2010 Slab Pour: 20 September 2010 Frame Complete: 23 September 2010 Fascia and Gutters: 28 September 2010 Roof Complete: 06 October 2010 Lock-up complete: 28 October 2010 Plaster complete: 29 October 2010 Fix-out complete: 22 Nov 2010 PCI 7 FEBRUARY 2011 Re: Geothermal ..... costs? 4Apr 18, 2010 8:11 pm dymonite69 Here is an article by the ATA: Geothermal 4 times the capital cost. About 1/2 running cost of an air-source heat pump (RCAC). The question is whether it will last long enough to pay for itself in savings. Thanks, I'd actually found that article through another geothermal thread. Sounds expensive. Frustrating really - I'd love to avoid using electricity for heating/cooling but it seems the reverse cycle keeps coming up trumps in terms of $$$. (We don't have access to natural gas.) Building on an acre in Macedon ......one day. Re: Geothermal ..... costs? 5Apr 18, 2010 11:18 pm The most cost-effective way of reducing your conditioning costs is by passive means e.g. optimising orientation, good weatherization, insulation, appropriate shading and radiant barrier. I don't believe in the concept of a 'zero-energy' building that doesn't involve fairly sophisticated solutions. In the course of my research I have investigated a whole range of 'high-tech' solutions * and there are no magical solutions. Most of them are either untried in the residential sector or too cost prohibitive **. You need to also factor in the materials and resources used to constructs these system and how long they will last. Any active system by nature will incur much more significant maintenance issues and problems with durability. On the other hand, an investment in the house design and construction will provide benefits that outlast any heating or cooling system. * ground source heat pump * radiant floor/ceiling * solar hydronic * solar air conditioning * absorption chillers ** true for turnkey solutions but there are cheaper DIY/bespoke ideas which you can find on the web but will need to install and maintain yourself. Re: Geothermal ..... costs? 6Apr 19, 2010 9:12 am dymonite69 The most cost-effective way of reducing your conditioning costs is by passive means e.g. optimising orientation, good weatherization, insulation, appropriate shading and radiant barrier. Despite having a great house design (and construction) to ensure all of this ^, we will still need some additional form of heating (though probably not cooling.) Am I right in assuming RCAC is going to be the most cost effective? At least in the short term ..... Building on an acre in Macedon ......one day. Re: Geothermal ..... costs? 7Apr 19, 2010 10:21 am Without access to natural gas, RCAC probably is going to be the cheapest conventional solution in the short to mid term. That's what I decided on. There are other important things you could do to reduce AC capital costs and running expenses e.g - combine them with ceiling fans in winter - choose to have only a few separate splits run independently rather than a whole of house ducted system - use some small low output radiant panels or mats right next to your desk or workbench for heating instead (particularly if you aren't going to be moving around too much) Re: Geothermal ..... costs? 8Apr 19, 2010 12:49 pm Thanks heaps for your advice (again!) It's always nice to have your opinion dymo. Who knows, by the time I get a planning permit (which may be years away the way we're going!) geothermal or solar panels may be a little more affordable anyway. Building on an acre in Macedon ......one day. Re: Geothermal ..... costs? 9Apr 24, 2010 9:27 pm I had an email back from the company mentioned in The Age. They suggested they could install a system in a 3-4 bedroom home for 30-45k ......... Building on an acre in Macedon ......one day. Re: Geothermal ..... costs? 10Aug 18, 2010 5:29 pm Sorry to "bump" an old thread but I guess it's better than making a duplicate! We are looking at green heating/cooling options for our house. In our current house we use an electric reverse cycle air conditioner. We like it because, being in Tasmania, most of our energy is clean anyway (hydro/wind). With our next house I'm hoping to go for a geoexchange/ground source/geothermal heat pump. I hear the huge installation cost is offset by the fairly significant reductions in energy usage (although our energy is green it still costs money!). Our architect has spoken to someone at a company which installs systems commercially, as well as has such a system in his own house, who has said: "For around 12kw you would require 3-4 x100m deep holes and it would cost around $35k (20k for the pipe and pump equipment = 15k for drilling)." Make of that what you will! Built 3br house in Glenorchy, Tas in 2001 * * * Built 5br courtyard house in Lenah Valley, Tas in 2011 - Homeone thread / Blog Re: Geothermal ..... costs? 11Aug 18, 2010 6:48 pm At 100m, this is true geothermal. A ground source heat pumps doesn't need to go so deep. Re: Geothermal ..... costs? 12Aug 18, 2010 7:16 pm dymonite69 At 100m, this is true geothermal. A ground source heat pumps doesn't need to go so deep. I was under the impression it could be either - we don't have a lot of flat, contiguous yard, so going down would be easier than going down a few metres then back and forth across the yard. I'm still learning though so I welcome any corrections! Built 3br house in Glenorchy, Tas in 2001 * * * Built 5br courtyard house in Lenah Valley, Tas in 2011 - Homeone thread / Blog Re: Geothermal ..... costs? 13Aug 19, 2010 11:25 pm dymonite69 At 100m, this is true geothermal. A ground source heat pumps doesn't need to go so deep. Hmm ours will only be drilled 30m - I think there will be 6 holes. Cost wise, it's about 10% of our build but the entire quote includes the compressor, hydronic heating upstairs only, in slab heating and the hot water service. The expensive part is the drilling + copper. The geothermal technology itself was around $20k. Downstairs - 11 squares and upstairs - 8 squares. Fingers crossed that there will be a retrospective government rebate coming... Re: Geothermal ..... costs? 14Aug 20, 2010 7:47 am Here is some info on ground-source heat pumps (GHP) - as distinct from geothermal sources GHP GHP ran twice as efficiently as an air-sourced heat pump (garden variety AC). So whatever it costs to heat a house with an RCAC, half that with a GHP. Re: Geothermal ..... costs? 15Aug 20, 2010 10:22 pm dymonite69 Here is some info on ground-source heat pumps (GHP) - as distinct from geothermal sources GHP GHP ran twice as efficiently as an air-sourced heat pump (garden variety AC). So whatever it costs to heat a house with an RCAC, half that with a GHP. Thanks dymonite69... yes when I say geothermal I mean ground-source or geoexchange heat pumps .. I think the inaccurate term gets used so often that it becomes common language sadly I've heard better than half the running cost, some sites claim 1/4 to 1/3. The fact that we are in Tassie, therefore it is even colder, will hopefully make it even more practical. Built 3br house in Glenorchy, Tas in 2001 * * * Built 5br courtyard house in Lenah Valley, Tas in 2011 - Homeone thread / Blog Re: Geothermal ..... costs? 17Sep 05, 2010 8:24 pm summergrace Hmm ours will only be drilled 30m - I think there will be 6 holes. Cost wise, it's about 10% of our build but the entire quote includes the compressor, hydronic heating upstairs only, in slab heating and the hot water service. The expensive part is the drilling + copper. The geothermal technology itself was around $20k. That sounds more reasonable than some of the quotes I have had so far summergrace... Can you tell me which company you are using? Re: Geothermal ..... costs? 18Sep 08, 2010 12:28 pm felicity1324 That sounds more reasonable than some of the quotes I have had so far summergrace... Can you tell me which company you are using? Direct Energy. Re: Geothermal ..... costs? 19Oct 25, 2010 12:06 pm Of course if you have a swimming pool, use that for heat exchange. Alternatively, an underground concrete tank can be used as described in this article: http://mtbest.net/heat_pump.html They dug a nice big hole and buried a 10,000 litre concrete tank in that hole. Normal geothermal systems have a pipe down a deep hole. But as soon as the ground gets cold surrounding that pipe, the systems efficiency drops off. But with 10,000 litres of water, the efficiency stays good until the whole of the tanks temperature gets lower, which would take some time. Plus, its relatively straightforward to add low-grade heat during the day. So, say, $4K for the tank, $1K to dig the hole - thats got to be a lot cheaper than drilling a very deep hole like the geothermal guys prefer. Probably works nearly as good too. In winter they used some cheap collectors to raise the temp a few degrees. The concept is that the water temperature stays pretty stable and that makes the heat exchanger work well. On a rural block, that water can also be used if there is a fire, to protect the house. Re: Geothermal ..... costs? 20Oct 28, 2010 7:31 pm Well I hate to contradict myself, but my previous post may have been a tad optimistic. I went to hear a talk by the guys from GeoExchange last night. They said it is possible to freeze the water in a swimming pool. It all depends on how much heat you extract and put inside the house which in turn depends on how well the house is insulated and how "leaky" it is in terms of air infiltration. The idea of a tank would probably only work if you add heat to it every day - eg with some sole collectors, which is after all what the guys do at Mt Best. I am not sure whether Perth has its own way of doing things in regards to this. Most of Perth has class A (sandy soil), except for some areas near rivers or hills. 2 13082 Looking to tile the facade pillars rather than rendering. Builder is quoting 2500$ laying cost for upto 10msq. The 2 pillars come to be 16msq. So laying costs are 5000$… 0 7542 10 15743 |