Thermo Storage Options

[Yianie123.]

Hello, I have a 90 tube (evacuated tube) hot water solar system.  It has an 80gal storage tank.  I want to increase the heat capacity for storing large amounts of hot water.  I use the hot water to heat my floor (hydronic heating).  I see that a lot of people built wooden square tanks with a rubber lining, others collect old water tanks.  I was wondering if anyone has seen or built thermo storage,tanks of water? or sand? Wooden tanks? any ideas will be greatly appreciated.

[bob g]

while i haven't built one, i understand that the wooden ones that are are
built with treated lumber and marine plywood, with a liner (which is made
for hot water, and who makes them i can't remember), are fairly straightforward
and simple to build.

from what i understand they make the liners in custom sizes to fit the containment you
have built.

when i finally get to that point i am thinking it would be a good way to go.

aside from that, getting as much heat that is comfortable into the floor during the day
and maybe adding more thermal mass to the interior to absorb more heat if it is available
might be easier in the long run?

bob g

[Yianie123.]

Thank you for your reply.  My understanding is that the liner is actually the same as a pond or rubber roofing material.  What do you mean by interior thermo mass?

[zap]

What do you mean by interior thermo mass?

Anything you add to the heated space is added mass.  Some mass will perform better than others.

Consider an empty room.
Let's say your present system on a typical day would heat that room to 70°F by 1pm and by 6pm the room is down to 65°F

Add a couch and a couple of chairs and it will now take till 1:15pm to bring the room up to 70°F but it doesn't get to 65°F till 6:15pm.

Add a half a dozen huge planters filled with water and now the room won't reach 70°F till 2:30pm, but... it doesn't reach 65° till 8:30pm.

Consider something a little different... something opposite.
Your fridge is completely empty except for that 2 year old mustard bottle
You open the door of the fridge hoping the food fairy has blessed you with a complete Thanksgiving dinner but alas... all that remains is the 2 year, 2 hour old mustard bottle.  When you opened the door the fridge spilled much of it's cold air out because there isn't much mass and the temperature increased from 38°F to 42°F.


Open the door of the 'beer fridge' which is almost always stocked and full and the temperature only went up a half a degree from 38°F to 38.5°F after you grabbed a brew. 

Why?  The bottles of beer and their contents kept most of the cold in their mass and kept it from spilling out when you opened the door.

[hayfarmer]

Zap,that's what I like about this board.very concise explanations ,make it easy for you to understand.lots of new guys /gals in the room,don't have to get headaches,

some of the topics and articles are real heavy for us new guys.but the advise saves allot of problems and (magic smoke) keeping us from

thinking too hard,my self included. "note to food fairy" please tell the beer fairy they have missed my fridge. 

hayfarmer

[Madscientist267]

Hayfarmer -

I gave up the beer myself, so when they stop by here I'll leave them a note to head your way.

Zap -

I had a couple ideas for this once -

'Decorative' 55 gallon drums full of Freon TF with heatsink fins on the sides . . . ?

- or -

Interior walls with water (or freon TF) tanks embedded in them . . .

Of course, getting one's hands on some TF nowadays would be pretty difficult, but when I thought about it (1992), the stuff was halfway readily available. 

It's amazing how much heat that stuff can hold.

Steve

[snowcrow]

I was thinking of using a 250 gal food grade container, about like the one in the link below.  The walls in the two containers I have are about 3/8 in.  in thickness.

http://cgi.ebay.com/275-Gallon-Reconditioned-IBC-Tote-Tank-/230467753063?pt=LH_DefaultDomain_0&hash=item35a8f2d467

[Madscientist267]

That would do it for sure.

I love how they call it a 'tote' tank.. haha Like you're going to fill it up and toss it in your backpack to bring it with you... 

Steve

[fabricator]

The actual name for them is Intermediate Bulk Container (IBC tote) the sizes are 275 or 330 gallons. (I have 12 of em full of used fryer oil waiting to be turned into bio diesel)