Detailed Product Description

Solar collector's efficiency test by  

TUV Rheinland Immissionsschutz und Energiesysteme GmbH.

η₀=0.754;

1st order heat loss coefficient , a₁=1.61w(m^2_×k) ;

2nd  order heat loss coefficient , a2=0.000w(m²×k²).

The collector performance is described by the equation for the power output q:

q = A*(n0*G - a1*dT - a2*dT²) [W]

With the operation conditions:

G : Solar irradiance on collector plane [W/m²]

dT: Temperature difference between collector mean fluid temperature and ambient air temperature [K] (Kelvin)

And the collector performance parameters:

n0: Optical efficiency

Combined efficiency of the transparent cover and the absorber [-]

a1: 1st order heat loss coefficient

Heat loss cofficient at collector fluid temperature equal to ambient temperature [W/K]

a2: 2nd order heat loss coefficient

Temperature dependent term of heat loss coefficient [W/K²]

The heat loss coefficient of a collector depends on the temperature. High values of a2 indicates large temperature influence

The higher the value of a2 the more "hookednosed" the power/efficiency curve)

Detail of material:

Outer tank: Al-Zn coated steel sheet

Inner tank: SUS 304-2B stainless steel sheet

Insulation: Polyurethane foam

Vacuum tube: Borosilicate glass 3.3

Absorption coating: Al-N-Al

Stand: Aluminum Alloy