i had an idea for storage

[101x81]

i have an idea for storage

a big concrete block buried and with 2 coils of pex, the concrete block, you can insulate it as much as you want and this act like a hx plate, tell me what you think

 

[pybyr]

The beauty of water as a heat storage medium is that it holds more thermal energy per unit of size/ weight than nearly anything else available- and by a considerable margin. Counter-intuitively, it can store much more in this regard than stone or other solid materials-- comparing apples to apples with the volume being the same. About the only way you can do better than water is if you get into exotic phase change materials. The only reason you'd want to rely on masonry as your thermal mass storage, rather than water, is if the masonry is also doing the end-heat emitting/ radiating.

Never hurts to think/ ask, though-- that's how we all learn, individually and collectively.

We're darn lucky that water is so good at retaining temperature; we'd be on an inhospitably chilly planet otherwise...

 

[jebatty]

Water has 4 to 5 times the heat storage capacity of concrete by weight. A cubic foot of water weights 62.4 lbs, of concrete in the range of 140-200 lbs cubic foot. Water vapor has almost twice the heat capacity of liquid water, and hydrogen gas has about 3.5 times the heat capacity of liquid water (all by weight). This is probably more than you ever wanted to know, but if not, *oogle "specific heat" to satisfy your curiosity.

 

[Chris Hoskin]

the heat transfer rate into and back out of the storage medium is an important consideration too.

 

[101x81]

thanks i will think again,
and buried fittings is not the best also

very helpfull to have you out there
the boiler room is best thing after the sliced bread

claude

 

[bigburner]

in the 70's there were plans that could be bought from mother earth news, you built a box out of concrete blocks and filled it with sand and CPVC pipe. fire box inside the sand, guess it worked KIND-OF I have about 600,000 pounds of concrete in my shop which is floor heated, it will suck up a bunch of heat, but with a low Delta -T its hard to get much extra reserve [flywheel] it stores heat for a couple days, with a steady loss, but storing usable heat here is not practical, if this worked you could run your under ground lines with out insulation and get some usable heat from the ground.

 

[leaddog]

in the 70's there were plans that could be bought from mother earth news, you built a box out of concrete blocks and filled it with sand and CPVC pipe. fire box inside the sand, guess it worked KIND-OF

I built one and it was better than using oil but there were MANY design problems and I ended up making some of my cpvc pipes go from 3/4 to 6in. Makes them REALLY thin and then they leak bad. Trying to get to much heat didn't work. Also they didn't tell me that the walls would crack and let the sand leak out which then let my cellulose insulation slide down next to the smoke pipe and had a very smoldering fire xmas day, just not in the stove. Ended shutting it down and now I've got my EKO in the shed. LOTS better technology and using alot less wood. My 2000 gal of water works better than sand to store heat. I think it is hard to find a cheaper or better storage than propane tanks for your btu's.
leaddog