A solar home to almost autonomous thermal buffer

[Christophe]

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

Here is what I thought: the rollers are in fact "radiator" ... and not what stores energy.

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 ...

Ah, here we go

[CRETE]

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

Here is what I thought: the rollers are in fact "radiator" ... and not what stores energy.

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 ...

Ah, here we go

that's what was wanted! = the pebbles had to exchange calories between air and earth ... a radiator sometimes at the place, sometimes upside down ..

in fact c a Canadian well "whose contact surface has been increased"

[minguinhirigue]

a Canadian well "whose contact surface has been increased"

It is a little different from a Canadian well anyway since the heat which "leaks" from the stock will be partly released in the slab of the ground floor and partly blocked by the peripheral insulation, hence the depth.

Christophe, the pebble storage that was messed up, in Belgium, were the pebbles under the house, in the ground, and were they deep enough?

The same kind of test was done with classic Canadian wells at shallow depth too close to the house (below or on the periphery) the well "sucks" the heat radiating from the house then diffuses it again in the form of warm air ...

So for air geothermal energy, either we play on natural temperatures and we isolate the well ducts near the house, or we play on annual phase displacements forced by the ventilation, and we place the tunnels with deep water under the house without insulation.

It remains to isolate the house with straw boots and the stove will be more than decorative!

Crete thank you for the images of your projects, they are very interesting, you correct me if I said stupid in the post.

Would you have references, or counter-references of projects using a water storage, like indoor swimming pool in greenhouse, related to the building to dampen the weekly variations of temperature? I saw those of Christophe, I saw the project at the base of the tread, but I have no project where the basin could have a nice complementary use, and where it does not remain locked in an insulating box. ..

[Christophe]

I do not know about pebbles, it was Guidi who had told me about it, he came back from vacation I would ask him the question as soon as I see him.

For the stamp it is certain: the more you get better it is ...

[Christine]

I have no project where the pool could have a nice complementary use, and where it does not stay locked in an insulating box ...

..do make a pool in sum. Not very recommended for reasons of hygiene, development of bacteria etc. The insulating box limits losses and saves money, which is the objective of the stock. And then bathe in a water at 50 ° C is average, limit 26 ° to swim in the summer it does not make sense for storage.

It is best to optimize for a single use.

[harry ravi]

I was in concrete reading and I thought of some things.

In order to facilitate the insulation of this concrete under the house, it will be possible to leave air between the ground and this concrete, limiting the thermal conduction by pillars.

In addition, this mass of concrete in the summer is not uniformly heated: the point of arrival of the water heated by the panels on the concrete in the summer will be hotter than the point of exit on the concrete.
So we have a warmer part and a colder one in winter during the inercie.

And if we reversed the entry point by the exit point?
The water first passing through the colder side of the concrete would go towards the hottest side (instead of going from the hottest side to the coldest while cooling).
As in the summer, the cycle is reopened so that the hot water arrives on the hot side and then cools to the colder side which may be cold enough to regulate the temperature down in the summer.

I do not know if you see what I mean but I see

[CRETE]

and we isolate the ducts from the well near the house, or we play on annual phase displacements forced by the ventilation, and we place the tunnels with deep pebbles under the house without insulation.

Do not insulate the PC ducts = fresh air inlet for the VMc, this air will continue to preheat in the "pebble tunnels"!

Pool vs. tunnels?

the water I have many times thought, but calculette in hands = it is very very expensive .. sealing, excavation of 100m3 earth (expansion = 150m3 ..), concrete walls to super insulation, 50 ° C difficult to maintain , powerful water sensors, very fine regulation and forced heating floor, the hot water tends to rise will overheat the DRC = seriously isolate the slab of the ground floor ...

so I turned to air systems, simple and rudimentary, little risk of frost, leaks all the way without gravity, air sensors OR veranda OR flat roof with steel tank or a mix of these 3 solutions to manufacture 'hot air
a single fan, in fact a super VMC ..., three times less volume of earth to excavate (25 to 30M ..) no expensive sealing ..etc ...

[minguinhirigue]

Yes, I understood that you should not insulate in the case of a roller tunnel (3 m deep). It is in a traditional PC (1 m deep) where it is necessary to take care to reinforce the insulation between the house and the catchment areas (and not "insulate the ducts" themselves as I wrote ), otherwise heat exchanges between wells and houses may be unfavorable.

The reason I was interested in water storage is that in a rehab project, I already have a pit of 2 m bottom, 2,2 m wide up, 1,8 m bottom, 25 m of long. This small volume is an old manure pit.

I planned to build basins for the phytopurification of the gray water of two houses (roughly 1000 liters per day).

Part of the pit must be partially filled, to recreate soil heights suitable for the development of different purifying species. In order: common reeds, hunting rush, marsh iris and aquatic mint, the last basin and may consist of water lilies and water hyacinths.

The maximum acceptable temperature would then be around 38 ° C.

For me, on this element it is not a storage inter-season, rather intersemaines. To dampen two particularly cold or hot weeks.

I'm trying a little sketch, it may help you to comment.

[minguinhirigue]

I abandoned the idea of ​​covering this volume, sorry, the project will have another head.

At first a few pebble tunnels under a greenhouse. Unfortunately, the orientation is not favorable for the greenhouse. I have 77 m2 glazing possible south-southeast and 190 m2 west-southwest facade! The first is useful but with a limited view, the second is very interesting for the view but with a risk of summer overheating not insignificant. Finally the roof and these 120 m2 can allow to install a canopy with some solar collectors replacing the blinds.

I thought for a moment to exploit the 120 m2 of the greenhouse with a tunnel with roller underneath, and a finish of the soil in ground groomed to profit directly from the losses of the stock (the under soil) in winter and to cool the greenhouse in summer ( overheating due to southwest orientation).

Today, I wonder if the simple fact of glazing less the west-south-west facade can not allow both to avoid overheating of summer, and the need for recovery of winter calories (tunnel to pebble), and at a lower cost (straw insulation 10 € / m² instead of glazing 400 € / m²!).

[Capt_Maloche]

It's the story of a guy who made a "Canadian" pebble well

at the end of 2 years, the guy had to abandon his installation so the germs of all kinds had proliferated in his inaccessible construction facility

Morality, do not use this type of well directly, but go through a double flow exchanger; blows, with the losses of the exchanger and the additional cost, the interest of this system falls to the water