You don’t always need a flashy renovation or a deep retrofit that requires gutting your building to boost energy efficiency. Sometimes the best things come in small packages – like these strategies by practicing FMs and green experts.
Covering a dozen aspects of streamlining commercial
lighting, these bite-size tips can provide the foundation for your next efficiency project. In the meantime, peruse lighting advice that helps slash energy costs and
1) Investigate Interior Fixes
Before tackling the lighting system itself, consider optimizing your indoor environment first. At the Mountain View, CA, headquarters of the social networking site LinkedIn, brightly colored walls complement ample daylight and efficient artificial lighting.
“In existing buildings, there are a number of things you can do with normal maintenance and upkeep or with a tenant improvement change to a floor plan,” explains Michael Hummel, senior sustainability consultant with Environmental Building Strategies, the high-performance building consultancy that worked with LinkedIn to create a two-story, 70,000-square-foot office building that later earned LEED-NC Gold. “One is just the color of finishes – lighter colors allow more light to bounce and there’s actually a significant amount of energy that can be saved just with lighter colors. Low cubicle walls allow both electric and natural light to reflect within the space in offices that can handle that kind of acoustic situation.”
2) Consider Daylighting Retrofits
If a structural retrofit is in the cards, adding an atrium can lend your daylighting utilization a big boost, Hummel says.
“LinkedIn has a really full building and couldn’t afford to give up any floor plate. In cases where you can, minor structural retrofits like bringing an atrium down through the middle of the building are not terribly complicated in terms of the payback for the effort put in,” notes Hummel. “We also see a lot of tech and up-and-coming companies that are trying to attract high-quality employees, and part of how they’re doing that is through sustainable design. Daylighting is a great way to do that.”
3) Make Cautious Lamp Choices
LEDs are widely heralded as the most efficient lighting source where lumens per watt are concerned, but you may find that other light sources fit your needs better. The LinkedIn project, for example, uses 32W T8 linear flourescents, while the BUILDINGS offices utilize linear T5s overhead and linear T8s for task lighting (see “The Dark Side of Poor Lighting”).
Don’t rule out LEDs completely, however – they may be the most cost-efficient choice in some spaces. One current project, a renovation of a large Boston library, includes a retrofit in an auditorium where fixed seating makes lighting access difficult and time-consuming.
“To get in over the seating, the client would have to bring in an adjustable lift like scaffolding or an asymmetric ladder to straddle these seats. Not only is there a cost to rent it, but that also means shutting down the space while they have scaffolding in there and getting someone up to the ceiling with a harness on. It’s a huge production,” explains Matt Latchford, senior associate for Lam Partners Inc., the architectural lighting design firm working on the renovation. “A lot of auditorium spaces still use halogen, and maintaining that is a huge endeavor.”
4) Lower Light Levels
Offices are notorious for overlighting, especially for computer-based work that adds light from the monitor to an already bright space. When the green building design and development firm Paladino and Company moved into its new home – a floor in a 10-story building – decision-makers set the default lighting level at 15 footcandles at the desktop and offered task lights on request. So far, not a single person has asked for supplemental lighting.
“That tells me that people are getting used to working in lower-lit environments than they typically have,” explains Brad Pease, director of building science practice at Paladino and a member of the in-house team that helped design the new lighting. “That means we’re overlighting spaces just by not challenging the conventions of how much light people need.”
LinkedIn used a similar strategy in 2011 when piloting a new wireless lighting control system in an office building more than 20 years old. Starting at 100% brightness for all fixtures, the team gradually dropped the light levels by 5-10% every few days until they reached the optimum balance. Combined with the extra light from computer screens – the majority of building occupants are engineers or IT professionals with at least two monitors – the low ambient light levels helped secure a two-year payback.
In fact, the pilot was so successful that LinkedIn expanded the retrofit-friendly control system to its entire Bay Area portfolio, as well as every new LinkedIn building worldwide where its installation is deemed feasible.
“We eventually got to 46 to 48% power the pilot building before the first person called us up to say ‘Hey, it seems like it’s a little darker than it was yesterday,’” says Eric McReynolds, environmental health and safety and sustainability manager for LinkedIn. “We were able to cut power by half before anyone even noticed anything. Then we went through with light meters to make sure we met all of our design requirements. That’s what we do in every building now – tune the system down to the point where it’s noticed and then pump it back up just a notch.”