Daylight as a driver of change

Daylight as a driver of change

Daylight drives change. It can’t help it. It always has.

Every minute of every day and every night on planet earth since it came into being, light has transformed everything on our little piece of rock, and continues to do so relentlessly. Some of these transformations are tiny - the chemical changes in the cells of a plant leaf to produce chlorophyll, for instance – even if their effect en masse is enormous - life on earth. Some of these transformations are incalculably vast, like the warming of the oceans, and the generation of their currents and motions.

The transformations that light stimulates affect minerals, vegetables and animals. Our very bodies and brains, our human emotions and moods, and those of every animal we share this planet with from nocturnal bats to sun-loving lizards, they are all governed by that strange entity that continually pours out of the sun and onto us
So ‘Daylight as a Driver of Change’ was a perfectly fitting theme for the 6th VELUX Daylight Symposium, held in London on 2 and 3 September.

These symposiums have been taking place every other year since 2005, on themes ranging from daylight and education to light’s impact on energy use, attracting hundreds of academics and professionals from educators to architects. But what kind of change can daylight drive?

The most fundamental change daylight wreaks in us, is in our wellbeing. Professor Koen Steemers’ talk drove home the consensus today on what both wellbeing and health in human beings actually are. He illustrated how our definition of them, via the World Health Organization, these days includes mental and emotional health, physical health, and the prevention of ill-health as well as cure. And light, as speaker after speaker demonstrated, is critical for preventing ill health in all its forms, but is just as critical for stimulating well-being.

These days we have the facts and hard data to back up our intuitive knowledge that natural light makes us feel better and behave in a more positive way. For instance, Arne Lowden, associate professor at the Stress Research Institute in Stockholm, showed how vital light is in regulating our body clock.

Daylight changes our bodies every day without us even noticing it. Where it is present – in the morning, perhaps – it stimulates our bodies to produce serotonin to energise us. Where it is not, in the evening, our bodies produce melatonin to help us doze off. And it is – in particular – the blue light so present in natural daylight, rather than the yellows or reds of artificial light, thatregulates our body clock.


That architecture can impact on this, as a conduit - or not - of natural light, by blocking it, transmitting it, capturing it or transforming it - was demonstrated again and again by the Daylight Symposium’s speakers. Light can help you work better. Professor Lowden, for instance, found that the further from a window office workers sit, the more fatigued and lethargic they are, and the more disturbed their sleep.

Daylight can help us achieve better grades. Stine Holm Jensen, from AART architects and Nafsika Christa Drosou, from Loughborough University, showed in their projects and research how vital natural daylight is in classrooms for maintaining the attention of students on their work and the teacher, rather than their own drooping eyelids.