Solar Heat & ole hoot blabb'n secrets. [Christian Material]

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For concentrated solar heating why not use the screen [front side] from a t.v. picture tube! Set the receiver at the focal distance originally made for the tube. Dependin on how large, old and style -the focal point could be anywhere from about 6" to 2 feet. The sunshine will be hot enough to start a fire if not done properly. Works best with hydronic versus air. Water/antifreeze solution needs to be moved continuesly to prevent boiling of liquid. The Receiver part needs to be heavy iron pipe or equiv. in order to withstand the extreme temps.

Several can be used in parallel to make a massive collector system. If'n ya'll want more info ---well rekon ya'll'l need to email or do some thinkin on ya'lls own. Now is the time to get more self-sufficient while there is still time.

Jesus Christ is coming back soon! Prepare now for His coming. Matt.24:44

-- hoot (hoot@pcinetwork.com), June 02, 2001

Answers

I would like more info Hoot. I always thought the TV screen was just a reversed movie screen,, its coated so you can see the picture, like the white of the screen.

-- stan (sopal@net-port.com), June 02, 2001.

I failed to mention [senior moment ?] the tube front is actually a large magnifing glass. All of the other glass needs to be removed from the tube leaving only the front. Focal distance can be either measured from the tube lens to the guns of the tube or--- just set the tube in sunshine and see where it comes to the smallest point of concentration. The coating needs to be removed from the inside of the lens [front] in order to intensify the suns rays. Don't think I've forgotten anything else but----????? Matt. 24:44

-- hoot (hoot@pcinetwork.com), June 02, 2001.

Can you draw me a picture or translate this technical stuff to blondespeak?

-- Laura (LadybugWrangler@hotmail.com), June 02, 2001.

laura,

blondespeak? ... now thats a new one! LOL (I love it.)

-- daffodyllady (daffodyllady@yahoo.com), June 02, 2001.


Blondspeak?! HA ha ha he he! Too funny! But don't fret, I'm a brunette and I didn't quite understand all of the tube/screen stuff... I think I'll be dropping hoot (that wise old owl) a line.

Peace to all-

-- Marty (Mrs.Puck@Excite.com), June 02, 2001.



I think you missed the safety lecture hoot! We don't want no folks 'imploding' any big picture tubes now do we! That could be a real nasty experience.

I dont pretend this is safe but what I do with old tubes before going to the tip is cover the tube with heavy carpet or sacks etc then break the little titty thing off the end of the neck. Once the air rushes in it is as safe as any other big piece of glass.

But are you SURE the front glass is a lense?

-- john hill (john@cnd.co.nz), June 03, 2001.


John! You're right about the saftey issue of the picture tube. Guess I'm gett'n old and forgetful---I just assumed that everybody knew that. Thanks for reminding me. I've never built this little gizzmotchie but a friend of mine has. He used an old picture tube from and early model Black and white t.v.set. I think it was an old 17" tube of 1960's vintage. The focal point was about 2' so that tell just how old it was! I don't know about new tubes or even color tu bes but assume they're similar. I do have a 25" tube that I'm savin for this task--that is if it will work. I'll know when I get around to build'n it.

Speakin of heating---we've just started offering, for sale, the new wood furnace, outdoor type, that Central Boiler is commencing to build. Called the "hydro-fire" and it's about $1,000 cheaper than the "classic" series. Matt.24:44

-- hoot (hoot@pcinetwork.com), June 03, 2001.


I understand colour tubes have a 'shadow mask' in the form of a metalic grid behind the screen. I dont know how that could be removed maybe easy or maybe not.

Sorry Hoot, I don't need a wood furnace :-)

-- john hill (john@cnd.co.nz), June 03, 2001.


I have had a think about the front being a lens, I guess it probably is although not out of optical consideration on the part of the makers. I just think the glass will be thicker around the edges as part of the manufacturing process and as they try to make the front as flat as possible you wind up with a convex lens, of sorts.

-- john hill (john@cnd.co.nz), June 03, 2001.

My brain is not working too well today, that should be a 'concave lens'!

-- john hill (john@cnd.co.nz), June 03, 2001.


Well...some CRTs do have a convex lens as the first surface, but most don't. My main concern here is the danger, mess and work involved in this project. The object here is to obtain a large convex lens to use as a concentrator, with the target vessel at the focal point. Skip the hammers and the picture tubes and simply purchase a fresnel lens for a few dollars from Edmund Scientific. The next problem you have to address is how your going to track the solar disc as it arcs from horizon to horizon. In a system as you're describing, this tracking is essential in order to keep the furnace operating. Not an easy task. Flat plate collection, while yielding lower temperatures due to lower overall gain do not require tracking. With regard to heating one medium (antifreeze/water) and moving that heat it to another (warmed air), losses will be inherent in the exchange. I've always preferred to warm air directly, allowing this heat to store itself in some sort of thermal mass (brick, stone, etc) taking advantage of the "flywheel effect" of said mass. But then again, what the hell do I know...only been at this since 1968.

-- Karl Keller (portlypaddler@yahoo.com), June 04, 2001.

ok now I've got 7 junked tvs behind my shed, a big pile of broken glass, cuts all over myself, and the only damn heat i got is coming from my head after going through all this. now what mr. smartypants??

-- Phil Abole (daytrader@hotbot.com), June 08, 2001.

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