Earth Heating

[Discomark]

Was over in Sweden recently and had a look at the in-laws house heating system. It looks like a normal central heating system with water pumped through radiators etc. The difference though is the heat is sourced from a series of pipes laid about half a metre below the surface around the property. I understand there is a fair amount of pipe required and at least a couple of hundred meters. They have a rural property so thats not an issue but you can also get bore holes drilled straight down if you don't have the space as their Son has done in town.

The system works on the principal that the ground is a few degree's warmer than the air temp and a heat pump amplifies this differential and subsequently heats water that is pumped through the radiators. They still need electricity to drive the pumps etc but this is a lot less that it would normally take to heat a house.

With the price of energy increasing in Oz I was wondering if anyone has installed or knows of anyone using a similar system over here?
I know it gets a lot colder in Sweden but they still use their earth heating in the "Summer" when the temp can still drop to single digits.

Cheers

Mark

[1976_michelle]

We'd be better to do something like that for cooling!
Havent heard of it before but I did do a project in High school (based on an idea dad gave me) of running water through coils of black poly pipe for heating it. My physics was a bit hazy as was my assignment dedication, but the results were positive enough for my physics teacher to install a system on his roof to heat his pool to a comfortable temperature

[Vern]

ground source heat pump. I wanted to do this for slab heating/cooling in our new house we built a couple of years ago, but NO ONE would return my calls, answer my emails etc...so it never went ahead which was a shame, as now i wish i'd stuck the plumbing in for it. works off the ambient temperature of the earth. quite simple.

[Dougal]

My inlaws had one outfit quote to install such a system and none of their numbers checked out.
Typical case of salesmen garnishing what used to be the truth to sell their system.
They were also hooking the system into the hot water circuit and claiming it would greatly reduce heating loads. Somehow they hadn't considered that you can't heat hot water at 60-65C with a heat-pump that only puts out 35C.

These guys were claiming the ground even where I live was a steady 12C a metre down all year. Now I keep forgetting to install temp probes, but I have seen ground frozen most of a metre down here in winter.

The actual unit was a Delonghi MTD, they are designed around sending water/glycol out at -3C and returning it at 0C.
The core parts of the system were sound, but I had zero faith in that pack of clowns to make a system perform as required.

[bee utey]

I remember reading about a ground source heat pump being installed in a community hall in Geelong, the article was in the ATA magazine. Try contacting them from their site: Alternative Technology Association website (http://www.ata.org.au/) they would be the most knowledgeable about where to search for a supplier.

[austastar]

Hi
The Marine Board building in Hobart was built with a sea water heating system, and that was back in the 1970s. It works by trying to freeze the Derwent River, and that is never much below 9 degrees.

cheers

[Landy Smurf]

hey discomark are you part of a swaussie couple? if you watch grand designs every second house on tehre do the pipes in the ground about 300m from memory and they use it for under floor heating. also where abouts in sweden were you?

[Discomark]

hey discomark are you part of a swaussie couple? if you watch grand designs every second house on tehre do the pipes in the ground about 300m from memory and they use it for under floor heating. also where abouts in sweden were you?
Hi schmierer
I guess we are a swaussie couple but i'm from UK originally so may not qualify ; )
The house is about 30kms from Växjö is Southern Sweden and the earth heating does seem quite popular over there and across Northern Europe.

The inlaws are pretty lucky in that they have a small creek running through the property and they have build a small hydro electric setup to make use of the constant flow of water. They produce between 7 to 10KW constant and year round so usually have enough to pump the surplus back into the grid and send the power company a bill (wouldn't that be nice!)
Cheers
Mark

[Landy Smurf]

i live 2 hrs south west of there.yes they are very lucky that they have the set up for it all constant water no natural disasters beside snow. and it funny what abit extra insulation can do to a place. when i build in australia i will make sure i go extra insulation and try and have at least 2 alternative energies because none of them are reliable enough all the time. i find it all very interesting and quite alot of it seems quite simple

[uninformed]

i live 2 hrs south west of there.yes they are very lucky that they have the set up for it all constant water no natural disasters beside snow. and it funny what abit extra insulation can do to a place. when i build in australia i will make sure i go extra insulation and try and have at least 2 alternative energies because none of them are reliable enough all the time. i find it all very interesting and quite alot of it seems quite simple

Well you may want to bring your galzing and insulation from europe with you. Double glazing here is double the price and insulation bats are rated at 3.0 not in the 20's and 30's like the USA etc :mad:

[Dougal]

Well you may want to bring your galzing and insulation from europe with you. Double glazing here is double the price and insulation bats are rated at 3.0 not in the 20's and 30's like the USA etc :mad:

They use a different R scale in the US as it's all about BTU's per F per square foot. I think.
In metric land (the world outside the US) it's watts per degree C (or K) per square metre. Or is that degrees per watt per m^2. I was using it two weeks ago and already I have it mixed up.

I have never got around to working out a simple conversion factor between the two. But fibreglass batts are pretty much the same the world over. For the same thickness, you'll have much the same insulation value.

Interestingly, even double glazing is terrible for insulation. R value of around 0.15 for single glazing and around 0.26 for double. Decent curtains can double that R rating.
Now how many movies do we see from the US where the main characters are living in unlined brick apartments with no curtains and crappy windows? IME the US and UK aren't that good at insulating their houses, they are just better at heating them.
It's the Scandinavians (as already mentioned) and apparently Koreans who have insulation and building methods nailed for cold climates.

[Landy Smurf]

they certainly are set up in scandinavia but australia is starting to head in that direction

[Dougal]

The new house standards here are pretty impressive too. The only problem is, takes about a century for new house standards to trickle down to the majority of the people.

The 27 year old house I'm in had no roof insulation when I moved in. Two storey house, vaulted ceiling upstairs. Was a fridge in winter and an oven in summer. On a sunny day with all the windows open it would run about 8C hotter than outside.
20C sunny day, 28C in my office.
32C sunny day, 40C in my office.:(

Over the last year I put R3.2 and R3.6 (started with R3.2, found R3.6 fit better) batts all through 100m^2 of roof. Batten and gib-board over it.
Transformed the house from terrible to quite good. It's still got a lot of bits that could be improved if I could get the bricks off the outside.

This winter we had a week with an average temp of -4.6C. I'd finished the insulation a few weeks earlier.:) I was able to keep overnight lows inside to about 12C when outside hit -10C and get it over 20C inside every day.

[Landy Smurf]

that is quite good. i know my uncle in canberra is doing a bit of insulating and blocking up drafts and he has noticed a big difference

[slug_burner]

I'd say that energy conservation standards as they apply to buildings have improved world wide much the same as the fuel economy of vehicles we drive have improved. Due to lower energy costs some areas may have been slower to take up the improvements. But now with costs as well as a growing awareness for climate change due to greenhouse effects improvements have been taken up in most parts of the world.

I lived in Canada for a short period and it is very apparent that they build for the cold with much better sealing of all habitable spaces, double glazing, insulating the garage from the living spaces where the garage is the bottom floor of multi floor dwellings. The houses did get pretty hot on a few days in summer particularly if you were not home to keep the windows open for ventilation.

[Landy Smurf]

that is probably one of the bigger downsides in lots of places in oz is that the temperature/climate changes so much oposed to the colder countries wher eit is cold most of the times but when in sweden it did get abit hot inside and it only got to 27c at the highest. i miss having a ceiling fan while there

[Dougal]

Umm guys. Insulation doesn't make your house hotter in summer.

The upstairs in my house used to be about 8 deg hotter than outside on a sunny day with all the windows open.
Now with R3.2 insulation all through the roof it sits at ambient temp in the full sun with the windows open.

Insulation is always better. Hot or cold.

[Landy Smurf]

i am not entirely sure on this one but you can get insulation that just keeps inside warm or cold but in australia most people probably have a general one. but generally insulation would always be better.

[Dougal]

All insulation does is slow heat transfer. The better your insulation, the slower the heat transfer and the less power it takes to keep one side hotter or colder than the other.

There is no fundamental difference between heating a workshop to 20deg when it's zero outside and keeping a coolstore chilled to zero when it's 20deg outside.

The 100m^2 of R3.2 insulation I've added over the last year, means with a 20C temp difference I am only losing 500w of heat through that 100m^2.
In comparison I'm pretty sure I'm losing 200w through each of the glass single glazed front and back doors.

The whole insulation makes a house too hot in summer thing comes from people thinking it's the same as them wearing too many clothes in summer. But there's a big difference.
With people we are the heat-source and more insulation slows that heat getting out. So we get hotter.
With houses in summer the sun is the heat-source and a better insulated roof slows the heat from that getting in. So it doesn't get as hot.

A great example of this is an insulated shipping container. If you leave them unpowered and shut up, then the temp inside stabilises at the average temperature over about a day. This is usually a lot cooler than the peak day-time temperatures.

[Discomark]

Well you may want to bring your galzing and insulation from europe with you. Double glazing here is double the price and insulation bats are rated at 3.0 not in the 20's and 30's like the USA etc :mad:

The house's i stayed at in Sweden all had triple glazing with argon gas between the layers. Imagine the cost of that over here!
I was also amazed that even the small pieces of decoration glass on the front door of the BIL's house was triple glazed as well.

[Dougal]

I think it's the swedes who have a very interesting window unit.
It's about two inches thick and has a double glazed outer pane with an opening single glazed inner pane and a venetian blind in between.

So you can open between the panes to clean/fix the blinds. You can open the whole window in summer without the blinds flapping around and breaking themselves and it's very well insulated.

It must be those long dark winters that give them all the time to think about such things.:D

[Landy Smurf]

i shall have alook when i get over there and try and find out how much it cost.discomark have you seen how cheap some of the real estate is over there?