For solar water heating in your home, there are basically two types of solar collectors: conventional flat-plate collectors and evacuated tube collectors. Evacuated tubes have a number of advantages: the work on overcast days, in colder weather, and the tubes can be installed and replaced individually without special tools.
The evacuated tubes act like giant thermos, allowing 93% of the sun’s radiation in, but only 3 to 5% out. Thermal conduction and convection losses are almost nothing (under 2%) because of the vacuum gap. This design allows the system to work in very low temperatures (down to about -40°F).
The only disadvantage is the higher price of these systems. For a residential installation you are looking at about $1500-$2500.
When using solar water heaters, you need back-up heating method. Tankless water heaters work best with solar installations.
The Solar Rating Certification Corporation rates solar collectors for sale in the U.S.
Here some retailers of evacuated tubes: Generation PV, Sun Spot Solar and Apricus, Omega 2000
4 thoughts on “Solar Evacuated Tubes: Free Hot Water”
Evacuated tubes are OK, but for subzerro temperatures you would want heatpipe manufactured in to the heater element http://pa-international.com.au/index.php?option=com_content&view=article&id=129&Itemid=174
Useful info at the bottom of the page, there are some calculators there to..
When did you buy these collectors. I have been thinking about buying off of them but I am questioning the quality of their current units.
Please email me @ dishman “@” canada.com
I have purchased several solmaxx evacuated tube collectors from Silicon Solar and think they are the best and cheapest. they can be found at http://www.siliconsolar.com
I think all new houses in the US should be built with solar power, we have become to realiant on foreign oil. In addition, we need to be more concerned with the environment which solar power would do by reducing pollution.