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Need a serious capacity Storage Tank for solar hot water ?

Posted: Thu Jun 18, 2009 12:26 pm
by TheyCallMeDave
http://www.plastic-mart.com/class.php?item=1534

I came across this Tank which can be put underground , and, it is safe for potable water. Has an inlet and outlet fitting . Thought it would be great for those who want to heat ALOT of hot water for bathing as well as space heating. Price is reasonable for 300 gallon capacity.

I was even thinking of getting one to be used as a temporary underground storm shelter since i live in a hurricane prone area. Even has a stand built into the bottom so you can sit down till the storm passes ! The inlet/outlet could be used for ventilation air while occupied.

Dave

Posted: Fri Jun 19, 2009 1:56 pm
by flcruising
The thing that must be determined, is how hot can it get. All plastics have a heat limit.

Have you considered these?

Tractor Supply

Or a series of metal (water heater) tanks?

Posted: Fri Jun 19, 2009 4:14 pm
by TheyCallMeDave
flcruising wrote:The thing that must be determined, is how hot can it get. All plastics have a heat limit.

Have you considered these?

[url=http://www.tractorsupply.com

Or a series of metal (water heater) tanks?
Aaron, Upon further investigation, Polyethlene plastic tanks max. out at 120 f. ..so that eliminates Plastic for Solar ; plus...only a very small variety of them can be buried underground . The one i posted can be buried, but, it is restricted to 120 f. which isnt going to help me. Im in need of a good size Tank ...like 150 + gallon storage capacity that i can bury and which will support at least 160 f. water temperature as i want it for my second project of Space Heating my Living Room /Kitchen/Bedroom using hot water Baseboard (or small Airhandlers with hot water coil) ; ideally , id like to use an Open System as they are much more efficient than a Closed System. From the site you posted, this may do the trick , although i think id need two : http://www.tractorsupply.com/webapp/wcs ... ue&cFlag=1

As for Water Heaters used purely for water storage ,I suppose i could bury them, but id need 2: 80 gallon . Kind of an expensive way to go . I may go this route afterall as they would hold up well underground plus they would have the insulated protective outer shell too. Dont have any room to install them inside, plus, 700 lbs. each (filled) is ALOT of weight for my floors. Thanks for the site . David.

Posted: Fri Jun 19, 2009 7:29 pm
by flcruising
You could build a shed. Or maybe place them horizontal just under the house.

RE: Need a serious capacity Storage Tank for solar hot water

Posted: Fri Jun 19, 2009 9:57 pm
by Johanna Bruns
Dave,

Before you bury a hurricane shelter, be sure that the water table is low enough that the storm surge or other flooding doesn't cause it to float. I grew up in hurricane country, and the high water table is why houses don't have basements on the coast. The floating coffins in New Orleans also come to mind.

Just FYI...

I've been getting my stuff together for a rainwater harvesting system, so I've Googled any number of tank sellers. One if the most reasonable is

http://www.plastic-mart.com/class.php?item=9

They ship about anywhere. There is a cheaper one in San Antonio (TX), but youu have to arrange your own shipping. I'm just lucky enough to live close enough to both to pick up myself--if it fits in a 14ft cattle trailer, I'm good to go.

Re: RE: Need a serious capacity Storage Tank for solar hot w

Posted: Sat Jun 20, 2009 6:46 am
by TheyCallMeDave
Johanna Bruns wrote:Dave,

Before you bury a hurricane shelter, be sure that the water table is low enough that the storm surge or other flooding doesn't cause it to float. I grew up in hurricane country, and the high water table is why houses don't have basements on the coast. The floating coffins in New Orleans also come to mind.

Just FYI...

I've been getting my stuff together for a rainwater harvesting system, so I've Googled any number of tank sellers. One if the most reasonable is

http://www.plastic-mart.com/class.php?item=9

They ship about anywhere. There is a cheaper one in San Antonio (TX), but youu have to arrange your own shipping. I'm just lucky enough to live close enough to both to pick up myself--if it fits in a 14ft cattle trailer, I'm good to go.
Yes, i knew about Plastic-Mart as the OP was one of their Tanks. My Well had to go down 50' so i think im ok on the water table for an underground shelter, plus, my land is sloped real good. Thanks for the link Johanna on rainwater.

Posted: Sat Jun 20, 2009 9:45 am
by TheyCallMeDave
flcruising wrote:You could build a shed. Or maybe place them horizontal just under the house.
Aaron, What do u think about using 55 gallon galvanized Drums buried upright , and adding a 3/4" inlet/outlet Port in the side ?

RE: Need a serious capacity Storage Tank for solar hot water

Posted: Sat Jun 20, 2009 9:56 am
by Yanita
I would never choose to go underground during a hurricane, water run off is another issue and what about air supply?

Yanita

Re: RE: Need a serious capacity Storage Tank for solar hot w

Posted: Sat Jun 20, 2009 11:00 am
by TheyCallMeDave
Yanita wrote:I would never choose to go underground during a hurricane, water run off is another issue and what about air supply?

Yanita
We are speaking of a temporary underground shelter, just for clarification .. as im also discussing hot water storage tanks underground in this same thread...which is probably a no-no.

If the plastic container mentioned in my opening post is put underground as a temp. storm shelter , the manhole access of the tank is not covered . It also has a good seal on it . Futher, the tank comes with two 3" bungs for attaching PVC piping which would be run above grade thereby allowing air supply into the vessel. In my situation, the runoff does not provide for any puddling water on my property since it is greatly sloped and is very sandy soil. Water almost instantly sinks into it.

RE: Need a serious capacity Storage Tank for solar hot water

Posted: Sat Jun 20, 2009 11:09 am
by Yanita
Thanks for clarification, not all land is equal LOL.

Sorry but I am not knowledgeable in the solar dept, need to educate myself as this is something I want to do as well.

Yanita

Re: RE: Need a serious capacity Storage Tank for solar hot w

Posted: Sat Jun 20, 2009 3:52 pm
by TheyCallMeDave
Yanita wrote:Thanks for clarification, not all land is equal LOL.

Sorry but I am not knowledgeable in the solar dept, need to educate myself as this is something I want to do as well.

Yanita
True...it all depends on the lay of the land. I think having a plastic underground temp. shelter using a Cistern Tank, would work real well for my application...but it wouldnt for everyone. I sure wouldnt want to float away in the thing...especially if i lived by the coast !

Posted: Mon Jun 22, 2009 10:27 am
by flcruising
Dave,

Have you looked into building your own EPDM lined storage tank? There are a number of projects on builditsolar that did this. One of them even simply dug a hole and lined it with foam insulation, then the EPDM pond liner. These systems are non-pressurized though, so not sure what approach you were going to take.

Posted: Mon Jun 22, 2009 3:08 pm
by TheyCallMeDave
flcruising wrote:Dave,

Have you looked into building your own EPDM lined storage tank? There are a number of projects on builditsolar that did this. One of them even simply dug a hole and lined it with foam insulation, then the EPDM pond liner. These systems are non-pressurized though, so not sure what approach you were going to take.
Thanks for that. The project burying a storage tank will be my closed / non pressurized system for space heating using water. Havent thought about using EPDM and ill look into it. It would be simplier if i could just find a galvanized steel drum that hasnt has and toxic chemicals in it. Id like to buy it horizontally directly under my domestic solar hot water heater so the piping run is short. I suppose 'in series' is how the two tanks should be piped (?)

Posted: Mon Jun 22, 2009 8:58 pm
by flcruising
So you are going to have two independent systems? One pressurized for the DWH, and one unpressurized for the space heating? Am I understanding this right?

The tractor supply in town (Crestview) had a 50+? gallon galvanized tank (not water heater, so would need insulation) that was a little over $100. You wouldn't have to worry really about temperature with a metal tank, so 180+ degrees would be no problem. And with water that hot, you could space heat, and use an anti-scald valve (I found one online recently for $20) to feed your faucets. 2 tanks wouldn't be unreasonably priced, and depending on the efficiency of your collector, 100± gallons, I'd think, would be enough.

I think I remember you mentioning that you were thinking of using baseboard radiators? Have you thought about an air-to-water heat exchanger installed in your air handler? This would minimize piping, and the thermostat could be wired to run a circulation pump for it too.

Posted: Tue Jun 23, 2009 10:15 am
by TheyCallMeDave
flcruising wrote:So you are going to have two independent systems? One pressurized for the DWH, and one unpressurized for the space heating? Am I understanding this right?

The tractor supply in town (Crestview) had a 50+? gallon galvanized tank (not water heater, so would need insulation) that was a little over $100. You wouldn't have to worry really about temperature with a metal tank, so 180+ degrees would be no problem. And with water that hot, you could space heat, and use an anti-scald valve (I found one online recently for $20) to feed your faucets. 2 tanks wouldn't be unreasonably priced, and depending on the efficiency of your collector, 100± gallons, I'd think, would be enough.

I think I remember you mentioning that you were thinking of using baseboard radiators? Have you thought about an air-to-water heat exchanger installed in your air handler? This would minimize piping, and the thermostat could be wired to run a circulation pump for it too.
I was going to have 2 independent systems till this morning when i figured out a way to have ONE open system for both the domestic hot water and space heating hot water...using the same solar collector . My concern is not having enough hot water stored for my evening hours in order to maintain 60 something degrees inside during our winter months here ; do you truly think Ill have 180 f. stored water if the sun is out and it only gets up to 55 f. during the day ? Further, is 100 gallons enough ? Ive considered installing a seperate hot water heating coil for the existing Air Handler , but need to find someone whos made the modification to see how effective it is. Otherwise, ill be looking at an independent compact Living Room fan powered Space Heater that incorporates a hot water coil . Im anxious to see how much hot water i get this winter from just the Domestic Hot water Solar System i install --- that will tell me volumes.