solar water heating

evacuated tube heat pipes

Category:

Science & Technology

Tags:

• solar
• hot
• water
• evacuated
• tubes
• heat
• pipes

[solution246]

Where can one get an evacuated tube?

[sundug69]

@solution246 Lots of places, but for some reason I cannot post links here, just do a search

[adxoplo]

How many BTU's per panel? Thanks, great vid.

[sundug69]

I have no way of knowing

[12robot345]

Okay, quick Engineering tip: Evacuating the inner copper tube is really a waste of time. The vacuum you're interested in is the vacuum between the glass tube and the copper tube. you want that so you don't lose the solar heat back out to the environment through conduction. A better plan: bigger copper tubes painted black. More surface area to absorb solar radiation. Pass fluid through tubes. Use anti-freeze so it doesn't freeze, and so the pipes don't corrode. Good luck!

[sundug69]

@12robot345 I did not evacuate the copper tube, I just heated the acetone some to drive the air out, nit the same thing at all. I know about the vacuum in the evacuated tubes. And the size of the copper tube doesn't matter, as the insulation value of the vacuum is so good that all the heat (not solar at this point) goes into the smaller tube as I have the copper scrub pads as conductors. This enables using less costly copper, and is the way they are made commercially. Forget fluid thru the tubes

[solution246]

@sundug69 I got it. Thanks so much.

[1foxtrot70]

LOL, that sounds like one of those exciting moments of science thru experimentation.

[sundug69]

Trial and error, and the error can get dangerous. Instead of rupturing the tube, the bulb blew off and went completely over my house!

[1foxtrot70]

How did you decide on 8 cc's of Acetone? I am sure this is one of those things where more is NOT better. I can see where an optimum amount, if exceded, would rupture the tube.