Turning off the lights to see the bigger energy picture
July 13, 2017
When’s the last time you interacted with your office’s lighting system? Many office workers come into offices with the switches already flipped on. Others have no control over their centralized lighting systems. And some work in environments that are so devoid of natural light that their only option is to keep on overhead lights during business hours.
For something so omnipresent, lighting is rarely noticed or even directly affected by those who use it. And that can contribute significantly to electricity costs and carbon emissions — lighting accounts for as much as 40% of energy use in office buildings.
Daylight Hour, a campaign launched by the nonprofit Building Energy Exchange in 2014, is out to change that. The campaign encourages offices to turn off electric lighting for one hour on one afternoon — a request that’s simple enough to be achievable, but unusual enough that it gets people to pay attention.
“A fair amount of energy is saved even by doing something as small as turning off a light switch,” said Tiffany Broyles Yost, a sustainability consultant at Arup who helped lead the firm’s participation in Daylight Hour. “But it’s also about understanding the impact of your choices and the habits we get into.”
Daylight Hour began with 140 participating offices. Since then, the project has grown rapidly. In 2015, 300 offices participated; this year, the number hit 820. The project also partnered with 12 city governments, which helped spread the word. The result: in 2017, turning off lights in 100 million square feet of office space across 17 countries (including nine Arup offices) reduced greenhouse gases by the equivalent of 310,000 miles driven by a car. The campaign also garnered widespread attention on social media, hitting 10 million impressions this year.
“We’re trying to create awareness and get the maximum number of people engaged in questions about energy use,” said Yetsuh Frank, the managing director for strategy and programs at the Building Energy Exchange. “A lot of us sit in office spaces that have daylight but we still keep the lights on, and it’s often nobody’s job to monitor these things.”
Frank said increasing awareness about lighting usage was especially important because people tend to use lighting when they need it the least. Peak office energy demand comes at midday, when there’s plenty of natural light. And peak energy usage is when the most carbon-intensive power plants — gas and coal — come online to make up for the shortfalls of greener energy.
Barriers to adoption
The people who organized Arup’s Daylight Hour said while this year was a success, there are two challenges to expanding the program: design and culture.
The biggest problem is that many offices simply aren’t designed to use daylight efficiently. In older offices, desks can be too far from windows, or the windows can be too small for 100 percent sunlight to be a viable lighting option.
But even newer “smart” offices often aren’t designed to allow daylight to be used in place of artificial light. In many newer buildings, lighting, window shades, and everything else are controlled centrally by computers, making it nearly impossible for an individual to turn off a light in an office when she wants to. “In that way, the system meant to simplify your life actually makes it more complicated,” said New York-based lighting designer Yuliya Savelyeva, who helped coordinate Daylight Hour in Arup offices.
The other problem is culture: many people are accustomed to using artificial lighting at all times of the day, and tend to be disconnected from natural light cycles.
“It was interesting to see how easily some offices got on board,” said Savelyeva. “The Australian offices were enthusiastic, which I think has to do with their relationship with the outdoors, which is different than it is in cities like Boston and Chicago,” where staff tend to rely more on artificial light.
That culture appears easy enough to change, though. Jack Lim, who oversaw the initiative in Arup’s San Francisco office, said that people there turned off the lights for Daylight Hour and got so used to it that they didn’t realize they were sitting without overhead lighting until late afternoon. Some people then complained that it was getting too dark, not realizing they could turn back on the lights.
That, Broyles Yost said, points to a deeply ingrained belief that environmental sustainability and efficiency equals discomfort. But this doesn’t have to be the case. “We just want people to ask, ‘Am I turning on the lights every morning and then not turning them off? Am I putting shades down and then not putting them back up?’”
“The idea is not to suffer,” she said, “but to be more in touch with your environment.”