Novel Solar Heat Dump??

gasfolk

During the summer, could you dump enough (and any objection to dumping) Btu's by

1) heating DCW by 10 or 15 degrees?

2) piping cold and hot to the outdoor sillcocks?

Warm toilet water??

gf

[Deleted User]

the solar pros here would certainly know,

but my guess with the extra plumbing/valves etc, that such a part-time dump wouldn't dump enough to make it worth the effort

mark s

I don't now if that would work without a storage tank. I would be concerned with growing nasties in the water at low temps.
I am working on a dump using the tankless in my oil boiler.

[Deleted User]

yeah, cooties would be a concern

unless you used a heat exchanger for the dcw, and didn't drink from the hose or toilet. but the dog wouldn't care if you did. dogs are generous that way

hot_rod

define how much

you want to dump? The re-cool function works very well with flat panel collectors. When the tank reaches a pre determined temperature it runs the pump at night to shed some back.

This will handle most 1.5 to 2 gallon per square foot arrays.

Running a radiant loop, in a garage for example could work.

Ideally you could use what the array provides and not need to dump.

Covering the collectors, or removing some of the evac tubes in the summer is another way to size down.

hr

gasfolk

Just thinking about wild possibilities...

The risk of overheating seems real, with potential frying of glycol, flashing to steam, Boeing noises, etc. Some describe heat dumps of copper coils in various materials, etc. Is there something simpler??

Would you sprinkle 80F water on your lawn? If I left for vacation and had no DHW use for a week, with concern for significant overheating, would a daily watering of 1/4 inch of DCW heated from 50-55F to 80F be feasible for dumping as many Btus as desired?? Would the grass suffer??

Just kicking ideas around. Heated toilets--we have a friend who paid dearly for a Toto with heat.

Cheers,

gf

[Deleted User]

Covering the collectors?

bingo! how about temp sensored, operable louvers?

[Deleted User]

Would the grass suffer??

use a temp or timed pump and sol valve to operate a fan sprinkler to chiller the water?

Unknown

Novel idea?

I'm sure it won't apply to your situation but I do have a novel idea. I should keep it a secret but I'll post it here anyways. You'll all know where the idea came from. First you need a house that will be passively cooled in the summer. This is essentially a house within a house with space between the inner and outer walls that will allow airflow. At the bottom of these walls there must be a means to draw cool air from underground such as long tunnels. Anyhoo, the idea is as the sun hits the house it warms the air in the space between the walls and causes it to rise toward some kind of venting system at the top, thereby drawing the cool air out of the tunnels and up the walls, cooling the house in the process. So, ok, MY idea is to build a cupola type structure at the termination / vent point on top of the structure. Then I would install basebord all around the inside of this cupola and feed the excess hot water (or most likely glycol solution)from my solar panels to this baseboard with some kind of smallish pump. What will this accomplish? Well, first off, it will dissipate that annoying and troublesome heat that has to be dealt with from solar panels in the summer but SECONDLY, it will further heat and cause an acceleration in the air just as it begins to exit the structure through the cupola, which in turn will cause an increase in the amount of cooling that can be derived from the passive cooling system as it will naturally pull more air through the walls than it would should this cupola setup not exist. Just a nutty idea I came up with looking at plans for a passively cooled house and trying to figure out how to cool off solar panels in the summer. Looks good on paper, don't know if it works or, if it does, how well. Novel, eh? Remember, this is TOP SECRET!! so don't tell anybody!! lol...

As a matter of fact, now that I'm thinking about it again, if we place the baseboard/cupola above the panels and configure the piping correctly, wouldn't it flow naturally by gravity and eliminate the need for a pump?

hot_rod

use the excess to power an absorbition

chiller, refrigerator, or freezer Find an old Servel and use the solar to "cool"

Build a "green" Jim and Tammy Faye Baker air conditioned dog house.

hr

gasfolk

Recirc through a flat-plate collector would only dump heat after sunset, so does not seem to protect against overheating during the day?? Covering or manipulating evac tubes is limited by the installation being three stories up?? Watering the lawn with 1/4 inch over a 25x25 foot area, with water heated from 55 to 80F, would dump about 20,000 Btus?? There are other options for heat dump.

Louvers and double-hulled houses seem designed to discourage further exchange, and though solar thermal seemed an extension of hydronic heating, this may be the wrong forum. I am looking for a more appropriate, solar-heating website.

Thanks,

gf

Unknown

Oh,

don't think that isn't being looked at!

I know it was a while back but they were trying to do the whole thing with just solar and it wasn't hot enough. I said, why not just preheat the ammonia with it before it hits the generator? They said, "Hmmmm..."

First thing I need to do is get myself a Robur and then take a close look at how I might go about that. I've tried talking them into giving me a "free sample" but it's not working. lol...

Unknown

There's some good solar people here...

just so you know. I'm not necessarily one of them. One thing I do recall from the Florida days was there were a lot of people with artesian wells that were specific to providing water to their water cooled a/c systems. They passed the water through the A/C and then into a lawn sprinkling system so every time the A/C ran the lawn got watered. So that particular idea is not too far off the mark. From what I understand it only requires a trickle to do the job for solar.

hot_rod

I researched solar cooling

for an upcoming article. There is a lot going on in that industry and in many countries. Robur is a major player as are many of the icemaker and refrigeration manufacturers. There are quite a few residential systems operating in various countries. Some systems are looking at "driving" temperatures around 130F.

hr

Unknown

Wow,

I did not know that. I thought Robur had dropped it. Something to look into! Thanks!

Can you get the article to me when it's done/published?

[Deleted User]

flow naturally by gravity?

sure, but at what rate/heat deposition?

and the cupola idea will really work well as a stand-alone, if also incorporated above the main stairwell, and open the basement door if there is a basement, all the way up through the stairwell/whole house 'chimney'

[Deleted User]

here's a free robur

find a junked motor home, bec they frequently have ammonia based units in them, and play til your heart's content

Unknown

Good idea!

I'll check around.

Unknown

Good question!

I just come up with the ideas, I don't do the math...

As I understand it, as long as we can establish a flow then stagnation is not an issue. I imagine if we wanted to boost flow we'd go with like 1" tube and high output baseboard. I'm drawing from my experience with an old homemade passive DHW system that was on a house I occupied in Florida. There was a tank in the attic and the solar panel (A box with 1/2" tube inside and covered with glass) was located just below the tank, connected by 1/2" tube as well. That system worked GREAT as long as there was sun. On a good day that water got up to 160*! On a bad day, well, I hope you like cold showers. lol...