Future indoor climate installed
in Halmstads Library
management of sun screening and lighting regulated by solar sensors
mounted in all directions.
The sensors regulate motorized window panels and airing gaps to make
indoor climate is as good as possible for visitors and employees.
A scrollable cloth is lowered from the ceiling, which functions as light
and temperature regulator in the summer and can be used as additional
insulation in winter.
The SEV solar sensor with 0-10V output 0-1500W/m2 is designed
to measure global radiation and the cosine adjusted head contains an
especially high-quality silicon photocell, which are sensitive to light
between 350 and 1100nm.
This head is completely airtight and can be left indefinitely in exposed
The sensor is calibrated for conditions prevailing outdoors, against
reference pyranometers that can be attributed to global standards.
Calibration thus refers to solar energy at a wavelength of 300-3000nm,
that is, the acceptance band for thermostat pyranometres.
Because of the different spectral reactions on the silicon photo cell
and thermo bars, the device must be used under natural light conditions
to obtain accurate readings i.e. outdoors.
Different weather conditions like sun, clouds, etc. will slightly affect
the calibration but the absolute difference will always be within 5% and
usually better than 3%.
During long measurement periods / i.e. monitoring of daily, weekly or
monthly levels) the differences become minimal.
The linearity is excellent with a maximum of 1% differnce up to levels
above 3000W/m2 (higher than normal solar radiation)
Typical daily Total Solar Radiation levels in the UK
Measured by a Pyranometer sensor, in Watts/m2
Winters day, overcast sky up to 150 Watts/m2
Summers day, overcast sky up to 200 Watts/m2
Winters day, clear sky up to 400 Watts/m2
Summers day, clear sky up to 1100 Watts/m2
Threshold level for measurement of 'daylight hours': 120 Watts/m2
Threshold level for measurement of 'sunshine hours': 200 Watts/m2
TAC Svenska AB, Halmstad