Solar Heat pipes

syboit

Hi,

I had looked into solar for heating water a while back and gone through all the pros/cons about tubes vs flat plate. Just as we are about to make our mind up, I see that firebird now do a solar heat pipe.

Just wondering if anyone has any experience with this option?

thanks

BryanF

syboit wrote: »

Hi,

I had looked into solar for heating water a while back and gone through all the pros/cons about tubes vs flat plate. Just as we are about to make our mind up, I see that firebird now do a solar heat pipe.

Just wondering if anyone has any experience with this option?

thanks

seems like its just a set of tubes to me?

Do-more

There are two main types of evacuated tube solar thermal panels. Heat pipes being one type and U tubes being the other.

20. What is the difference between U tube and heat pipe collectors?

U tube collectors have a copper pipe, attached to a heat absorbing fin, running from the top of the solar vacuum tube and making a U turn at the bottom. Heat pipe collectors have copper heat pipes inside the evacuated tubes, with water only flowing past the header of the collector. Both collectors stand high pressure and look the same externally but the U tube can be used in any orientation. Heat pipes can not work lying flat; the bottom of the pipe must be lower than the head

21. Which solar collector is most efficient?

U tube collectors are almost exactly the same efficiency as copper heat pipes under standard conditions. In persistant low light, the U tubes should be better than any heat pipes, since they have no minimum start up light required. Copper heat pipes are slightly more efficient than glass heat pipes, with faster starting in low light, but yearly average performance is very similar. Any heat pipe is more efficient than water in tube. Any vacuum tube collector is more efficient than a flat plate collector if the air outside is more than a few degrees cooler than the hot water inside. Lowest cost is a different story-the all glass heat pipes win on that.

22. What are the advantage of a copper heat pipe solar collector versus u tube collectors?

Extreme high pressure-since only the manifold is pressurized, and heat pipes ends have a much smaller area than several meters of pipe, higher pressures are possible. Better drain back-draining the top manifold is easier than several meters of pipe in a u-shaped path. More resistance to corrosion and failure-less water in contact with metal and less volume pressurized mean less risk of failure. Less circulation pump load-path of water is only through the top manifold, not through several meters of pipe.

23 What are the advantages of u-tube solar collectors versus heat pipe collectors?
Flexibility-U tube collectors work in any orientation, including horizontally flat roofs, or on edge such as on walls or balcony mounts, while heat pipes only work tilted between 15º and 75º

http://www.seabirdsolar.com/scripts/faqs.php