April 6, 2011
Once upon a time, joking about ‘how many it takes to screw in a light bulb’ was a great way to poke fun at people’s intelligence. After all, what could be easier than screwing in a light bulb? Any idiot could do it.
Not so any more. Lighting has exploded into a sophisticated business. And for those who manage commercial buildings it can be downright intimidating.
Figuring out the difference between LEDs and CFLs is just the start. Then there are a whole range of dimmers, sensors, data loggers and controllers, both wired and wireless, and computer software to bring it all together. There are considerations to be made about light harvesting, interior space planning, and human behavior. And while learning all of this, the building manager is constantly wondering, ‘Will I really save energy? Will my utility bills drop enough to justify the investment?”
Clanton & Associates, a Boulder, Colorado company, is trying to help answer the big cost questions in a newly released, six-month study of life cycle costs for lighting control systems and technologies. Researchers looked at buildings in Boston and Los Angeles that had installed efficient lighting systems.
Dane Sanders, professional engineer at Clanton & Associates, says his company was trying to address the “fear factor” that exists for building owners when it comes to lighting projects. “The growth of these types of systems is happening so fast that keeping up with the technology is difficult,” he said. “This helps people understand the real benefits of advanced lighting control, and gives some basis for people to make decisions about what lighting control systems best suit their ends.”
The study offers some interesting findings for those making their way through the maze of options. Wireless controls, for example, deliver up to 25% lower lifetime costs than comparable wired systems, according to the paper.
Wireless systems with full dimming capability – a Cadillac system — seem to offer the best bang for the buck. “It pays back relatively soon; that is a very interesting conclusion. Just doing the minimum isn’t necessarily the best. A bit more investment upfront can pay back very quickly,” he said.
Dimmers also get points for being less jarring on the eyes than a sudden on/off of lights. “With dimming it happens slowly and smoothly and is imperceptible,” Sanders said.
In addition, it does make a difference who sits where in a building. The study finds the ‘inverted space plan’ works best, even though it runs counter to traditional office planning. In the inverted plan open offices are located on the perimeter, where the maximum number of people can take advantage of natural lighting. Private offices are pushed to the interior