Benefits in terms of thermal comfort, glare protection and energy consumption

Halio’s Smart-Tinting Technology passes tropical test

A study by the BCA Skylab Singapore has compared the electrochromic technology of Halio® glass with classic 2-layer thermal insulation glazing plus mechanical sun protection.
The results show that smart-tinted glass improves user comfort and lowers energy costs while maintaining visual contact with the outside world. 100% of the glare was blocked, between 17 and 25% of the energy costs for the lighting was saved and over 95% of the test period, a good room comfort was achieved.



Halio International has published the results of a full scale laboratory trial conducted by the Energy Research Institute of Nanyang University of Technology in Singapore. Halio‘s electrochromic glazing technology, known in the market as “smart-tinting glass,” was tested under real-world conditions at BCA Skylab, one of the world‘s most spectacular laboratories. “The study results prove that we can rightly call Halio technology an innovative, green solution for the buildings of the future,” said Benoit Domercq, General Manager Europe and Middle East at Halio International.

Rotatable platform allows different lighting scenarios
On the roof of a 7-storey building, two identical test rooms of the BCA Skylab, each with 43 m2 floor space, are mounted on a rotatable platform. This allows technology tests under tropical conditions as well as different solar irradiation. More than 200 sensors are available for measurements.
In the Halio study, a façade with Halio glass and a façade with conventional double glazing with low-E coating plus shutters were installed next to each other in the test rooms. Both rooms mimicked the identical office situation. The results show that Halio technology outperforms traditional low-e glasses in three areas: anti-dazzle, thermal comfort and energy savings in lighting.


Visual comfort: glare protection
Shots with an HDR camera that covered the complete field of view of a building user show that Halio blocks even extreme glare for 100%. The test period included three consecutive afternoons with the test facades facing west. The values recorded by the camera were converted into the glare code DGP and, according to Wienold and Christoffersen (Wienold, 2006), were classed in the four categories imperceptible, perceptible, disturbing and intolerable glare.
A total of 3 hours of “intolerable glare” and 1.25 hours of “disturbing glare” in the reference room would have forced the users to lower the blinds and thereby also interrupt the connection with the outside world. In the test room with the Halio glazing, however, no glare due to daylight was measured during the entire three days. Even when completely dark, Halio Glass remains transparent. Since the control adjusts the tint level automatically to changes in the glare intensity, the building user always has the best daylight access.

Less artificial lighting necessary
At the same time, the improvement of visual comfort was accompanied by a reduction in energy costs for lighting. The test room, equipped with Halio glass, required 17 % less energy when facing west and 25% less energy when facing north compared to the closed-blind reference situation.

Improved thermal comfort
Last but not least, the differences in thermal comfort according to DIN EN ISO 7730 and DIN EN 15251 were also measured. In the calculation of PMV index (personal well-being) and PPD index (dissatisfaction percentage) according to ISO 7730, the climate parameters included room temperature, mean radiant temperature, room air humidity and indoor air velocity.

Again, the results show clear advantages of electrochromic technology. Over 95% of the time, the Halio glazing test room provided a comfortable category B climate, compared to 75 to 78% in the room with double glazing and open or closed blinds. This suggests that the Smart-Tinting, in addition to preventing glare, can also sustainably improve the energy input from the outside and thus the thermal comfort.

References
Wienold, J. C. (2006). Evaluation methods and development of a new glare prediction model
for daylight environments with the use of CCD cameras. Energy Build. 38, pp. 743-757.

About Halio International
As the exclusive supplier of Halio products and services to the building industry, Halio is a joint venture between AGC, the world’s largest flat glass manufacturer, and Kinestral Technologies, Inc., which develops and manufactures Halio smart-tinting technologies. The joint venture comprises two entities: Halio North America and Halio International. The partnership leverages the partners’ respective strengths and knowledge: AGC’s reputation in the building industry and 100+ years of experience in glass technologies and Kinestral’s innovative, patented smart-tinting technologies.


Halio International
www.halioglass.eu