EcoRenovator  

Go Back   EcoRenovator > Improvements > Solar Heating
Advanced Search
 


Blog Register 60+ Home Energy Saving Tips Recent Posts Search Today's Posts Mark Forums Read


Reply
 
Thread Tools Display Modes
Old 03-10-21, 12:29 AM   #1
jeff5may
Supreme EcoRenovator
 
Join Date: Jan 2010
Location: elizabethtown, ky, USA
Posts: 2,394
Thanks: 410
Thanked 604 Times in 506 Posts
Send a message via Yahoo to jeff5may
Default Cheapest most effective solar thermal system ever

Due to a few armchair conversations with the masses, I've decided to build a few of the cheapest, most effective solar thermal collector panels ever. Here's the plan:

I did some research online and with a few (real) people that have been operating thermal collector panels for a few years. I've decided not to mess with antifreeze or highly pressurized rigs. This leads me towards a drain back system.

Low wallet dent/ high eco recycle factors also apply here. Something like a higher performance version of a flat plate plastic pool heater is the object here. I've got an endless supply of 3 foot wide storm windows and corrugated metal roofing also.

I have a fence about 100 feet long at the north side of the property that runs really close to due East - West that would be a good place to put the array. The spot would get total solar exposure until about 3pm, then the shadow of the house creeps down the fence row. Decreasing exposure until about 6pm when the shadow reaches the back corner of the fence.

The corner of the house nearest the fence is where the heat pump is located, so there's an ample chase to run plumbing above the basement drop ceiling that's somewhat isolated/insulated but accessible as well. That corner of the house is where the master bath (ground floor) and the basement bathroom are located. Behind the basement bath, there's a little equipment closet with a sump pump on it's own 20 amp breaker. Probably room enough for a 50 gallon water heater and more plumbing.

As of now, I'm open to suggestions. Main purpose of the system is to decimate my electric bill. Heat domestic bath and shower water, and keep the basement warm. Not trying to build a massive insulated aquarium in the basement. If I need a big heat store, it'll be an ibc container sitting next to the heat pump.


Last edited by jeff5may; 03-10-21 at 12:41 AM.. Reason: Information
jeff5may is offline   Reply With Quote
Old 03-10-21, 05:57 PM   #2
jeff5may
Supreme EcoRenovator
 
Join Date: Jan 2010
Location: elizabethtown, ky, USA
Posts: 2,394
Thanks: 410
Thanked 604 Times in 506 Posts
Send a message via Yahoo to jeff5may
Default

Looking for a suitable design, I found one on builditsolar. They call it the MTD collector, short for modified trickle down.

https://www.builditsolar.com/Experimental/MTD/MTD.htm

There seem to have been two guys (Richard and John) collaborating on a few different versions of the basic design. John has some YouTube videos up describing a few of them. I like this idea because it uses a variety of materials for the actual absorber, that all seemed to work good enough to heat water up above the 150 degF range. It uses polyiso "Rmax" boards for rear insulation and mylar sheet for a waterproof membrane. Pretty much "zero pressure" drain back operation.

John built his panels out of light gauge galvanized steel "stud wrap" channel, that's dirt cheap. My local Menard's has them in multiple sizes for between 3 and 6 dollars each per 10 foot stick. So between the stud track and insulation, I can probably build a 10 foot long (probably a little shorter, due to the Rmax being only 8 ft long) enclosure for under 50 bucks.
jeff5may is offline   Reply With Quote
Old 03-10-21, 06:12 PM   #3
pinballlooking
Super Moderator
 
pinballlooking's Avatar
 
Join Date: Jun 2013
Location: SC
Posts: 2,844
Thanks: 166
Thanked 541 Times in 444 Posts
Default

Nice project. I have considered doing this in a closed-loop fashion to heat my fish water.
__________________
Current project Aquaponics system , Passive Solar Greenhouse build

To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.

Solar Install 12.5 Kwh-
To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.

Mini Split installs -
To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.

EV Chevy Volt -
To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.
pinballlooking is offline   Reply With Quote
Old 03-13-21, 09:35 PM   #4
jeff5may
Supreme EcoRenovator
 
Join Date: Jan 2010
Location: elizabethtown, ky, USA
Posts: 2,394
Thanks: 410
Thanked 604 Times in 506 Posts
Send a message via Yahoo to jeff5may
Default

Nope, not trying to do a copper skeleton and roll form or solder or both. If it was going on a roof, if it was meant to last 50 years, if I had a big budget... Maybe. Too high speed high cost for my "meager" purpose. For fish or swimming pool duty, the plastic micro channel heat soakers are very bang for the buck. I had some and they don't bust when they freeze if you don't touch them.

Anyhow, I went shopping at menards and came home with 3 pieces of 3-5/8 track, 2 pieces of 1-5/8 track, and a sheet of polyiso Rmax board. 1 inch was 20 bucks, half inch was 10 bucks, and 3/4 inch was 13 bucks, so I got 3/4 inch. Grand total of about 34 bucks. I had a chat with hotrod / ratrod builder buddy, and found a few suitable watertight back things for the wet collector part: plastic store sign panels. Pretty close to the same thing as gas station signs without the number brackets. He had two that were long and skinny: smaller was about 2 ft x 10 ft, larger about 3ft x 15 ft. Good enough for prototype duty. We're still negotiating on price, but I may be able to get them for sweat.

I found a water pump on FB market for 10 bucks also. 12 volt RV duty, 3 gallons per minute with a built-in pressure switch. Previous owner took the pressure switch apart and couldn't put it back together. Go figure. Rigged it to my truck battery and jumped the switch contacts to verify no moving parts gremlins in the actual pump, and it spit out some moisture. Yee haw! Thanks, see ya, zoom! Flojet model 03526 looks up easy on the net, dude had a Ziploc bag full of guts and fittings for the pump body, so whenever I can carve out some time I've got just about everything I need to get something made.

Another possibility: it's fake spring here. All of the pilgrims are getting rid of their old hot tubs. For some more sweat and some beers, I could probably score one for free. I absolutely NEED another hot tub. One if those appliances you either love or hate and I love 'em. It would make a great heat dump for all the extra summer output.
jeff5may is offline   Reply With Quote
Old 03-21-21, 04:26 AM   #5
jeff5may
Supreme EcoRenovator
 
Join Date: Jan 2010
Location: elizabethtown, ky, USA
Posts: 2,394
Thanks: 410
Thanked 604 Times in 506 Posts
Send a message via Yahoo to jeff5may
Default

We finally got a clear day that wasn't windy. I got the small one about whipped together today. A buddy had a bunch of wood shelving this week, and I grabbed half a truckload of it from him. So the back of the panel is gonna be 5/8 x 12 inch slats of particle board. He had solid wood, but I traded it to hotrod guy for the plastic store signs.

Next layer up is the polyiso, then the plastic sign collector, top is gonna be classic single storm window pane in aluminum frame. Yes, they'll butt up fine, I just have to remove the spring loaded latches and pins from the corners.

All this sandwich is wrapped in the steel stud channels. The small collector absorber is gonna be corrugated galvanized steel roof, painted BBQ grill flat black. Paint was a toss up between engine paint and BBQ paint. Engine paint can said use primer and don't eat it. BBQ paint said wire brush, rinse, dry, spray. Non stinky, non poisonous. Hopefully that means no off gas after the initial dry and bake cycle.
Attached Thumbnails
Click image for larger version

Name:	IMG_20210320_172040920_HDR.jpg
Views:	127
Size:	541.3 KB
ID:	9254   Click image for larger version

Name:	IMG_20210320_172032421_HDR.jpg
Views:	123
Size:	575.8 KB
ID:	9255  
jeff5may is offline   Reply With Quote
Old 04-27-21, 03:49 AM   #6
osolemio
Hong Kong
 
Join Date: May 2010
Location: Hong Kong
Posts: 108
Thanks: 20
Thanked 17 Times in 13 Posts
Default

Interesting experiments, Jeff.

What is the latitude of your location?

What elevation angle do you plan to install the panels at?

If the panels have any tilt to them, you could consider to look at the area in front of them. You write they are mounted on a fence, right? So if there is a somewhat reflective surface in front of the panel, you should get extra performance out of them.

__________________
Space heating/cooling and water heating by solar, Annual Geo Solar, drainwater heat recovery, Solar PV (to grid), rainwater recovery and more ...
Installing all this in a house from 1980, Copenhagen, Denmark. Living in Hong Kong. Main goal: Developing "Diffuse Light Concentration" technology for solar thermal.
osolemio is offline   Reply With Quote
Reply


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -5. The time now is 07:01 PM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2021, vBulletin Solutions Inc.
Ad Management by RedTyger
Inactive Reminders By Icora Web Design