Light that follows the day: blue-rich and bright when people should be alert, warm and low when they should be winding down. Energylight luminaires can be specified with BIOS SkyBlue, the only circadian technology with a peak at 490nm.
The human body evolved to benefit from bright days and dark nights over a 24-hour cycle. Spending long hours indoors, away from daylight, has broken that relationship. Circadian lighting puts biologically effective light into the places daylight does not easily reach, so people's rhythms stay aligned with the day.
Brighter days, darker nights
Our internal clock is kept in time by light entering the eye, and it is most sensitive at 490nm, the blue of a clear sky. That wavelength has largely been engineered out of modern LEDs in the pursuit of efficiency, so daytime light indoors is biologically dim, and light at night is biologically too bright. The result is a body clock that never gets a clear signal.
The benefits of biological light are the ones you would expect from a clear signal: a stronger circadian rhythm, more alertness, better productivity, better mood, and better sleep.
SkyBlue
Energylight luminaires can be specified with BIOS SkyBlue lighting technology. It brings the benefits of blue skies inside, and is the only circadian lighting technology with a blue peak at 490nm, giving the industry's highest melanopic ratios at 3500K and 4000K, with colour rendering of R9 above 90. Tunable, it runs high through the day and drops back at night with minimal visual change.
It is designed for the WELL Building Standard, which measures the features of a building that affect health and wellbeing, and reports in the metrics WELL and the CIE use: equivalent melanopic lux and melanopic ratio.
What a circadian scheme needs
Product is the smaller part. Effective circadian lighting is spectrum, timing and placement together:
SkyBlue tunable spectrum in the luminaire.
Optical control, to avoid glare and deliver vertical illuminance to the eye.
Lighting and spatial design by an engineer or lighting designer.
A control system that delivers the right light at the right time of day.
In 2019, experts in chronobiology, sleep and light set out recommendations for the lighting industry, built on the CIE's metrology for light's non-visual effects. Energylight has adopted them as the pathway for interior circadian design. For the science behind them, and the spectra side by side, read Circadian Lighting: Evidence-Based Design vs Standards-Based Design.
The Energyline systems below can be specified with SkyBlue. The projects show circadian thinking at work in healthcare, where the time of day matters most to the people inside.
