heating costs and sustainability

[Rogerwlt]

I am planning a new build of about 120M2 between Limoges and Perigueux on a 4000M2 site site bought build to start circa 2007

In Britain I would have installed a Condensing Gas boiler to heat water and provide Central Heating BUT no mains gas.

 Although a Wood burner seems a valid choice on a "zero carbon" basis the thought of having to buy my heating needs in at least a year in advance as well as storage and drying the wood worries me .

Has any one out there considered, researched, costed or even installed any of the following:-

Central heating oil or propane powered Combined Heat and power.

Ground source or Geothermal Heat Pump perhaps with heat recovery from waste water i,e around the fosse septique as well as the usual under soil receptors.

a combination of the two?

I am using a ten year period to compare costs

 

Roger Thomas

 

 

[Jeremy]

we have considered the geothermal system as our French plumber reckons it would cost at 2 euros per metre square per annm to hear our 400 m 2 house. Trouble is he has already installed the new Oil fired boiler at a cost of 10,000 euros.. Thanks a lot.

He has said a soil heat recovery boiler and bits and bobs would have been about the same cost..... But he is very sorry to forget to mention it. He will change the system if we want, for 10K euros.....

Good Luck.

[Teamedup]

Are you sure you will have planning permission in 2007, there is a time limit on this sort of thing and I cannot remember how long it is.

[Rogerwlt]

Planning permission:-

I have just reapplied to extend the CU (outline planning permission) for a further year (from march 2005) giving me march 2006. My information is that you can renew the CU if you apply within the two months prior to its expiry by means of a letter to the Mairie otherwise a new application is required hopefully I can either re apply again or go for a full 'permis de construire'(Detail planning permission) in that time. Which is why I am doing my research now.

Or have I got it wrong?

 

 

Roger Thomas

[Mazan]

If I were renovating or building again there is no question that I would go for low temperature wet underfloor heating powered by geothermal with oil backup. To which I would add a solar unit for hot water production. And probably a reversible air-conditioner, depending on the location of the house.

Underfloor heating is so much better than radiators that I can't imagine why it isn't standard in every decent new house.

Whatever the current insulation spec is when you build: double it.

[Jonzjob]

That's nice to here Mazan,

The house we are buying has low level, wet, under floor heating, but just on LPG. The hot water is solar with LPG backup. And the insulation in the roof is 100mm on the ceiling and 180mm under the brick roof under the tiles. It's classed as Bioclamatic with huge patio doors South facing in the living room and 2 bedrooms with the roof shielded in the summer, but allowing the sun in to heat it during the winter.

Even the terrace has the under floor heating, but isolated, so that if we decide to glaze it in all we have to do is turn a tap and that's heated too. The place was built, by the owner, 20 years ago and he really thought it out!!!

John (soon to have warm feet!)

[Mazan]

The house we are buying has low level, wet, under floor heating, but just on LPG.

Before taking over the LPG contract you might want to investigate the possibility of ripping out the gas boiler and installing an oil boiler and tank. LPG can be very expensive and once you've signed you're locked in for years.

[Rogerwlt]

 

Has to be underfloor never had a second thought. I would also instal a wood burner for A) The smell and boring B) as back up. DO EdF consider this to be Electric Heating for tariff purposes?

 When you reverse the pump in summer (for cooling) do you have a condensation problem on the floor or do you blame the dog?

Still no feedback on CHP ie where you have a small generating set and use the coolant for domestic heating, searches to date claim efficiencies better than 95% and in the uk there is a scheme to sell excess electricity back to the grid. for the techies out there try  http://www.stirlingengines.org.uk/manufact/manf/misc/sig.html

or for heat pump and ground array quotes  http://www.kensaengineering.com/ they're in the west country but I have no connection.

As an aside: If you are tied into a long term supply contract for Propane and would like to reduce costs could you install a CHP unit powered by propane and save on electricity to offset the apparent horrendous cost of even bulk propane?

Ebay have s/h reversible heat pumps on their auction site from £50 if any one is considering air con or is this advertising?

 

Roger L-T

[zeb]

A friend is going for geothermic air pumped underfloor heating (depending on devi). Doesn't need the vast amount of land or 150 ft bore hole that I thought and she has been told that it saves on electricty. There is also large (40% I think) refund for this method through l'impots.

She is meeting with guy (who advertised in Maison et Travaux and is based in southern Charente) on Wednesday to discuss so I will post after that.

Has anyone here got firsthand experience of this method?

[Rogerwlt]

No first hand experience but web search gives reduced efficiency with air sourced heat pumps rather than ground or water sourced, further reductions in efficiency were quoted for systems that relied upon underfloor hot air ducts, dire warnings of the need for the floor and the ducting to be insulated.

EdF vivrelec(I think) advertise a 15% tax reduction.

[Cat]

Fella and me, we're going for geothermic heating, sourced from 3 (dry) bore holes (more efficient than the "snake" type shallow system, and doesn't need acres of land.

Heat pump, water heater, installation, underfloor heating, bore holes et al coming to around 20,000 euros... gulp

Expensive initially, but with the tax refund initiative for renewable energy, low running costs and low maintenance we figure it will be the best bet in the long run.

[Hegs]

Hi Cathy,

I'm really interested in this, could you provide some more details? How big is the surface area you are heating, is it a renovation or a new build? Do you have an idea of how the cost splits ip into underfloor heating runs/machinery/outside piping?

[Cat]

[quote]Hi Cathy,I'm really interested in this, could you provide some more details? How big is the surface area you are heating, is it a renovation or a new build? Do you have an idea of how the cost splits ...[/quote]

Hi Hegs,

it's a new build, about 160 sq m to be heated, all on the same level.

Unfortunately I can't give a cost break-down yet, as the price is a ball-park figure given by the geo-therm company when they came to look at the land and for the initial survey (apparently they have to ascertain feasability with a prliminary visit).

We decided on the 3 bore-hole approach as we didn't want to tie up a lot of land for the shallow run horizontal system (might want to plant orchard/dig swimming pool or something in the future).