Posted by Jeff on December 18, 2007, 12:31 pm
Assuming I finish my water collectors (I have three to finish
rivetting) I'll need a water store. I had thought of just making an EPDM
lined box (although I've had trouble finding the width I wanted).
Someone had mentioned plastic drums. I'm assuming those are HDPE
polyethylene. It seems to me the upper temp limit would be marginal
(~160F 70 C).
Anyone have any experience with either plastic or steel drum heat
storeage? I'm assuming both can be near free, which meets one of my
Posted by Morris Dovey on December 18, 2007, 3:09 pm
| Assuming I finish my water collectors (I have three to finish
| rivetting) I'll need a water store. I had thought of just making an
| EPDM lined box (although I've had trouble finding the width I
| Someone had mentioned plastic drums. I'm assuming those are HDPE
| polyethylene. It seems to me the upper temp limit would be marginal
| (~160F 70 C).
| Anyone have any experience with either plastic or steel drum heat
| storeage? I'm assuming both can be near free, which meets one of my
I have some of both in my shop, but I've never tried using 'em for
heat storage (I use steel drums for dust collection and poly drums as
While I was putting my dust collection system together, I discovered
that most major metro areas seem have a (steel) barrel
cleaning/reconditioning business. They clean and "reline" (sand blast
and repaint the inside) barrels, then sell them to folks who need 'em
as shipping containers.
The barrels are available with either removable (clamped) lids or with
a pair of screw-in top bungs. When I last checked a couple of years
ago, a reconditioned barrel (in Omaha) was about $0.
Stainless steel barrels are sometimes available, but they're at least
a full order of magnitude more expensive. I think I recall a quote of
$00 for a used s/s barrel.
The poly barrels are more often free if you can find the right source.
My first poly barrels came from a hospital and had contained x-ray
stop bath (and smelled stringly of acetic acid until washed). You may
be able to get some of these from a local car wash since they seem to
be the container of choice for detergents. The last poly barrels that
I got had held orange juice concentrate, but a friend (who had gotten
them from someone I didn't know) dropped them off at the shop and I
don't know where they came from (the stencil on the side says
DeSoto, Iowa USA
Posted by gary on December 18, 2007, 4:08 pm
My understanding is that the commonly available plastic barrels start
going soft at around 130F.
You might ask the question on the Yahoo SolarHeat group -- there are
some people there who use a collection of plastic barrels for heat
What width of EPDM do you need?
Around here, its available in 12 ft and 20 ft wide rolls.
Places that do landscape ponds usually have a big roll that they will
cut pieces off of.
On my EPDM lined plywood tank, the insulation cost more than the rest
of the materials for the tank, and might deserve some attention.
Posted by Jeff on December 18, 2007, 5:41 pm
Oh, that's not good. Of course that still leaves steel (as Morris
mentioned)... In Cleveland (where my brother lives) I can get stainless
steel drums for about $0, but I'm 700 miles away in a city with almost
OK, that's new to me.
The 12'. We've had a drought here and the landscaping place I was
going to pick up the liner from went bust. I can find the 20'...
I think you used polyiso and would have lined the inside to keep from
pinching the liner.
I can only get half inch here. I was thinking of a double box, the
outside shell would be thin plywood (could be poly) and filling the
space with cellulose loose fill (a half inch sheet of polyiso inside and
out). Moisture is not the problem with cellulose as it is with
fiberglass. I'm unsure what to do with the bottom although I could build
a frame of 2x8s or 2x10s. With the 2x10s I'd have an R of ~10 due to the
insulation of the wood and the bulk of the R would be the insulation.
What R did you insulate your tank to?
Posted by gary on December 19, 2007, 2:40 pm
Mine has 2 inches of polyiso just inside the lining (for temperature
reasons) + 4 inches of extruded polystyrene (blue) + some
miscellaneous bats over the top that I had left over that may not do
much. About R12 + R10 +R10 = R32
But, mine sits out in the cold.
If you could use the cellulose and keep it dry, that would save quite
a bit I think.
Keeping it dry probably just means a lid that seals well so that you
don't get water vapor coming out all the time.
To get mine to seal well, I had to back up the insulation lid with a
sheet of OSB, and use long deck screws about every 12 inches around
the periphery. It then has a very small pipe to vent the air pocket
above the tank to atmosphere.