Geothermal Energy

[Babnik]

Has anyone installed geothermal heating, and if so any recommendations? Various different technologies to choose from...a little difficult to separate wood from the trees!

Steve

[Thedunnes]

I too have looked into this a little.  There is an english chap who I know who lives in Normandy who has been involved in helping a firm who manufacture the equipment in France.

Simply put he explained to me that installations work better the bigger they are.  As a small system and a large system would both need a similar sized compressor to extract the heat, thus making a large system more cost effective.

The one house I am doing at the moment is only small and so I am probably going to install a regular oil fired boiler but with a separate hot water tank to allow me to use a solar system to heat all the water in the summer and assist the boiler int he winter.  Yes they do work in winter as well but do need help.  There is still a huge barn to get my head round and I will look at Geothermal heat for that.

hope this is some help, but if you have a decent sized property and want to know more I will dig out this chaps address and let you have it.

Stephen

www.forsac.co.uk

 

[Babnik]

The property we have is pretty large, and we have decided on Geothermal heating. Only problem is there are various technologies, Sol/Sol, Sol/Eau, Eau/Eau, and obviously everybody says their system is the best, and the competition are not to be trusted! Very difficult to find out what is true and what is sales speak!

[Hegs]

I'm finding the same thing. I am starting to wonder if the best thing to do is to install the in-house heating pipes etc when renovations are done but leave the heat pump and (?)field until the technology has bedded down a little. Hopefully the costs will go down as well!

I'm also confused about how much land area is needed for each option, and how good the interior insulation should be in a renovation.

Also, and I know I should go find out for myself, but how do the tax refunds work, lets say a 40% income tax rebate on an install of EUR 20000, does that mean I pay EUR 8000 less tax, or that my declared income is reduced by 8000?

Any clues?

[Babnik]

As to land area, there are several options depending on what land area you actually have. Horizontal option needs around 120% of the area to be heated. Vertical option, doesn't need much lan at all, but I guess is quite expensive and depends on the tye of land you're trying to bore a hole in. Third type depends on the water table, and again depends on the water table being present and is more a vertical solution. As to insulation, as with all heating systems, the more the better. The less you have, the harder the heating is going to work. We have decided to insulate all outside walls (to whatever the norm is) and only leave internal walls in stone. As to tax credit, it is indeed 40%, and I always assumed it meant you'd pay less tax in subsequent years. Their is also a ceiling. I have found prices to be failr reasonable with quotes in the region of around eur 16000 for an area of 165m2. This includes the underfloor heating. I'm sure if I were to go for radiators and oil fired boiler I'd get a bit cheaper, but not too much! With the tax credit, it's a no brainer.

From what I can gather, Sol/Sol or Fluide/Fluide is the simplest system, and basically has two systems of Refrigerant Fluid, with the heat from the outer fluid directly heating the inner fluid which flows through your underfloor heating. Advantages : Simple. Disadvantages : Cannot regulate room by room, cannot use existing radiators and cannot have an option for cooling in summer. Sol/Eau, uses a system whereby the outside system is again refrigerant, and the heat is indirectly, through an exchanger transmitted to the inner water system. Advantage : Since the inner system is water, can be used in traditional radiators, each room can be regulated independently and can be reversed in summer for cooling. Disadvantages : Dunno! Where is get's complicated is that each system has what is called a coefficient, which seems for most systems to be in the region of 4. What that means is that for every 1 kw of electrical energy (you didn't think you were going to get something for nothing did you?), you get 4kw of heat. I say most systems are around 4, but nobody gives you exact figures. The guy pushing Sol/sol tells you his system is more efficient, while the guy pushing Sol/Eau tells you the opposite. If anybody knows the answer to that question, I'd be very interested to know it.

For those with pools, it's possible to heat the pool using the same equipment, BUT only when heating is off. Basically it will extend the duration of pool use to those months where it's warm enough to have no heating, but too cold to swim. I guess April/May and September/October. Doesn't sound like much, but does double the amount of time you can comfortably use the pool.

As you can see I've done my homework, but still a few unanswered questions remain!

[bigjimbishop]

http://www.avenir-energie.com/english/acceuil/frame.htm

These guys may have an answer at a price.

I found the link here... http://freeenergynews.com/index.html

My favourate site

Jim

[Rogerwlt]

I'm only a new boy and searching for info like you but have you looked at >House renovations>ground source heat pumps or >heating costs and sustainablity yet?

Personally I'm worried that an air sourced system would fail i.e freeze up, at low temperatures just when you most need it. but I'm willing to learn.

Roger L-T

[Fridgeman]

Hi All

air sourced system will freeze up but will not fail they are used today all over the world, when the outside coil freezes over a sensor sends a signal to the controller which in turn tells the system to reverse cycle which defrosts the coil and then turns back again onto heating mode.

hope I have explained the principle clearly

Regards

The Fridgeman