A solar home to almost autonomous thermal buffer

[the middle]

Hello,
And the pebbles? caught in a river? not good

[CRETE]

that the T ° of the "well" falls to 10 ° C

No, by feedback on several houses = end of February = 14 ° C to 17 ° C ...

At the end of the summer, the earth's temperature is around 25 ° C to 28 ° C depending on the surface of the veranda or the air sensor

therefore slow release on 3 to 4 months in winter from 26 ° ~ 28 ° c to 17 ° C ~ 15 ° C ..

Pebble 150m3 will provide 1 / 8e or 13% of annual heating requirements

I am not a fan of "pebble pools" and I preferred to place spaced trenches in the median of the future house
and in the end, we have a natural reservoir of 250 300M3 compact earth with better management of the phase shift of the thermal wave.

this type of storage ensures a good third of the heating needs and the air quality (appreciable in the south
Where is ...)

with a roof fault, are these linear losses so important?

Yes, 56 ml of wall exceeding insulation and 20cm thick = 11.8 m2 of uninsulated wall equivalent!

not to mention the fact that the roof insulation is only 16cms of rock wool that could have been worn at 24 or 30cms because the roof / wall ratio is high

With better insulation, we would have fallen well under the 25KWh / m2 / year ECS understood ..






the horror, with the bullshit of the entrepreneur, that my client gave up attacking, too eager to live there, without making waves ..


the trenches, instead of digging a cellar full of pebbles!





deep, huh ?? and it was cold in the middle of August ..
we put 80cms of rollers in height + polyane + tubes PVc to bring / recover the air having walked in 5ml of rollers with the speed of 0.1ms ..

[CRETE]

Hello,
And the pebbles? caught in a river? not good

Simply ordered to a company and anyway, it only takes 6 to 8m3 for a home of 125m2 livable (50 / 80mm clean rolled rollers

and NOT 150 to 250m3 of pebbles for "fans" of pools filled with pebbles to place under the house !!!

it is the solid earth which stores the heat around the gelts which only serve as a heat exchanger, in one direction or the other, and these "tunnels" filled with gaets are an economical alternative to 100 to 150 ml of PP or sandstone pipes that should have been put in place for air-land exchanges.

[Capt_Maloche]

Thank you for the photos, it's very informative

So 30% of the heating needs thanks to the regeneration by the veranda in the Toulouse area, and a little less in the Paris area. It's not bad at all !

but the defect of this system is that when you need cooling at the height of summer, it is at this time that you load the "well" to bring it up to T °, ​​it is a hell of a calculation of inertia
or else there should be 2 independent.

for thermal bridges, if the outer wall is insulated from the inside, damage will be limited

Do you have other projects of this type made / ongoing?

[Christophe]

I had echo of a storage by thermal buffer in stone pebbles ...It had never worked well ...

But it was not in the south of France. (must be heated in the south ??? ). Guidi told me about it. So it could be in Belgium.

In your case the pebbles seem to be more exchangers (exchanges house-underground) than real thermal buffers alone.

What is the CP of pebbles you use in comparison to water?

[Capt_Maloche]

Crete will answer more precisely, but I based on Concrete, 2 times less than water in volume

[Christophe]

Ben I think there is another advantage with the pebbles: air can flow between them and so you find a kind of natural convection that have water buffers.

For the concrete heat buffer, we had already talked about it and you know that I do not agree with you

The "thermal concrete" poses many problems: thermal and mechanical (expansion) but also cost ...

Question: how are the heated floors done? It's a special concrete?

[Capt_Maloche]

For the concrete heat buffer, we had already talked about it and you know that I do not agree with you

Question: how are the heated floors done? It's a special concrete?

It's your right , and I'm not sure to use it one day, I'm simulating for now and looking for ways to accumulate a max of calories

The heated floor concretes are dosed "stronger" in cement, a fine sand is used and a special additive is mixed in order to thin the mixture and stick perfectly to all the exchange surfaces.

the fact of the fluidify avoids to vibrate it to drive out the air bubbles

[Christophe]

Ben, luckily, we have the right to disagree !!

Even if one day you dare (even a proto) I would be curious to read the results.

Ok for PCs, so it's not a very specific concrete. From what I understand it is especially the planeness that one seeks and the chasing of the bubbles (logic), nothing special therefore at the level of the concrete against the dilation?

[CRETE]

but the defect of this system is that when you need cooling at the height of summer, it is at this time that you load the "well" to bring it up to T °, ​​it is a hell of a calculation of inertia

In the spring, the 300m3 is between 15 and 17 ° C and it takes 3 months to raise the temperature to more than 25 ° C

the air coming out of the rollers remains below 26 ° C until mid July, end of July

Beyond 26 ° C, we do not store but we do not get air through the house but directly to the air sensor or the veranda

or else there should be 2 independent.

An achievement in this direction will have leu in Hte Savoie with the installation of two independent pebble tunnels, one "cold" and the other "hot" to have more flexibility in the management of steockage / destocking

in fact it is an external Canadian well associated with a set of these pebble tunnels ("hot")

herewith an installation of "tunnel" pebbles before backfilling by compacted layers of earth + all-terrain, the type had planned to make a "pool" filled with pebbles but quickly realized that the 180m3 of pebbles him would be expensive; there he only put 12m3 ... as exchangers

Works completed end of June

last week, the air coming out of the pebbles was 16 ° C ...



herewith a standard plan for the distribution of trenches under the slab