Solar Evacuated Tubes in Houston, Austin, and San Antonio

Evacuated tube collectors have multiple evacuated borosilicate glass tubes which heat up solar absorbers and, ultimately, solar working fluid (water or an antifreeze mix—typically propylene glycol) in order to heat domestic hot water, or for hydronic space heating. The vacuum within the evacuated tubes reduce convection and conduction heat losses, allowing them to reach considerably higher temperatures than most flat-plate collectors.
Evacuated tube collectors are made of a series of modular tubes, mounted in parallel, whose number can be added to or reduced as hot water delivery needs change. They have rows of parallel transparent glass tubes, each of which contains a collector tube (in place of the collector plate to which metal tubes are attached in a flat-plate collector). In some cases, the tubes are covered with a special light-modulating coating. In an evacuated tube collector, solar heat passing through an outer glass tube heats the absorber tube contained within it. The absorber can either consist of copper (glass-metal) or specially-coated glass tubing (glass-glass). The glass-metal evacuated tubes are typically sealed at the manifold end, and the collector is actually sealed in the vacuum, thus the fact that the absorber and heat pipe are dissimilar materials creates no corrosion problems. Some systems use foam insulation in the manifold. Soda-lime glass is used in the higher quality evacuated tubes manufacture. Newer technology evacuated tube systems use a coated glass-and-metal absorber. The glass is a boron silicate material and the aluminum absorber plate and copper heat pipe are slid down inside the open top end of the tube. In lower quality systems moisture can enter the manifold around the sheet metal casing, and may eventually be absorbed by the glass fibre insulation and finds its way down into the tubes. This can lead to corrosion at the absorber/heat pipe interface area or freezing ruptures of the tube itself if the tube absorbs water.
Vitosol 200-T Vitosol 200-T


Vacuum tube solar collectors.
Absorber surface area: 22 and 33 sq.ft – 2 and 3 sq.m

The Vitosol 200-T is a high-performance vacuum tube solar collector that is ideal for DHW/combination space heating systems with versatile horizontal or vertical installation on roofs, walls or freestanding. The Vitosol 200-T is ideal for incorpation into any architectural design.

Vitosol 300-T Vitosol 300-T

Vacuum tube solar collectors.

Absorber surface area: 22 and 32 sq.ft – 2 and 3 sq.m

The most environmentally-friendly method of domestic hot water heating, as well as a backup/supplement for low-temperature heating purposes.

Thanks to the highly effective Sol-Titan coating, the vacuum tube collector Vitosol 300-T can even utilize diffused solar radiation. It is therefore suitable not only for domestic hot water applications, but also as a backup for central heating purposes.