Evacuated Tube Collector
ETC-30 Apricus evacuated tube solar thermal collector
Construction
Evacuated Tube (ET) - Absorbs solar energy and converts it to usable heat. A vacuum between the two glass layers insulates against heat loss.The Heat Transfer Fin helps to transfer heat to the Heat Pipe.
Heat Pipe (HP) - Copper vacuum pipe that transfers the heat from within the ET up to the manifold.
Manifold - Insulated box containing the copper header pipe. The header is a pair of contoured copper pipes with dry connect sockets that the heat pipes plug into.
Mounting Frame - Strong and easy to install with a range of attachment options.
Evacuated tube and heat pipe
The Apricus evacuated tube and heat pipe are assembled in a patented format that is different to any other product on the market. Rather than a centrally located heat pipe with heat transfer fins radiating out to the glass wall, the heat pipe is positioned directly against the glass wall, where the sun strikes. The aluminum heat transfer fin is tightly held against the top inner wall of the evacuated tube and heat pipe with a set of spring clips. This is an important design feature as over time, with exposure to high temperature, the aluminum will soften. The spring clips guarantee long term tight contact with the glass wall and heat pipe, which is essential for optimal performance.
Header Design
The header pipe in the AP series evacuated tube solar collectors is designed for reliability. Large fluctuations in operating temperatures from day to night cause thermal expansion and contraction of the metal, which, combined with high operating pressures, places a huge amount of stress on brazed connection points.
In contrast to most other header designs that have 2 brazing points per heat pipe (60 for 30 tube collector), the Apricus design uses a twin contoured header pipe design that allows "dry" connection ports that don't penetrate the header pipe. This means the header only has 4 brazing points in total. The result is an extremely reliable design that is able to withstand the rigors of daily thermal cycling.
Flat Plate Collector
Glass
Toughened glass (glazing) protects the absorber from the outside environment while allowing through >90% of sunlight.
Absorber
A thin sheet of Aluminium is coated with a highly selective material that is extremely efficient at absorbing sunlight and converting it into usable heat. The aluminium sheet is ultrasonically welded to the copper riser pipes.
Insulation
The insulation helps reduce heat loss from the sides and back of the collector. Made from ultra-light weight melamine foam this material is chosen to greatly reduce the weight of the collector.
Back Sheet
An aluminium alloy sheet seals the back of the panel and adds to the rigidity of the collector.
Riser & Header Pipe
The header and riser pipes are brazed together to form a harp shaped heat exchanger that the solar system heat transfer fluid circulates through. The absorber sheet is ultrasonically welded to the riser pipes, thus transfers heat to the heat transfer fluid.
Aluminium Rails
Extruded from high tensile 6063 aluminium alloy, the rails form the outer framework of the collector and are designed with wings for easy mounting frame attachment.