Adapted from a presentation at the Central Penn Business Journal’s Real Estate & Development Symposium
When thinking about building energy efficiency, here’s an idea: let’s all agree to have no more bright ideas! He can have good ones and even great ones, but no more bright ones.
Why? As it turns out, many offices are still over-illuminated, and lighting accounts for 20% of a building’s energy consumption – even more in some older buildings.
Lighting designers and engineers used to design for the most light possible – that was just the way you did it. So if you’ve ever wondered why your office is as bright as an operating room, now you know.
JDB Engineering’s team still goes into existing buildings and find that they have up to twice as much light as they really need – or double the maximum light levels required by code!
Too much lighting lowers productivity (eye strain, headaches) and increases heat – resulting in the need for more air conditioning during the warmer months.
A good low-cost approach is to replace older T12 light fixtures with energy efficient T8 or T5 fixtures. Many building owners have already done this, but if you still have T12 lighting, get rid of it! While you don’t have to worry about this if you are in a newer building, we are always surprised to find that many older buildings still have the older, energy-wasting fixtures!
Use natural light to the extent possible. You probably don’t need to have window shades open and all your overhead fluorescent lights on at the same time, do you? As someone once said, if you don’t have a floodlight on your computer at home, why do you at work?
Consider using task lighting only, or reducing overhead lighting and supplementing it with task lighting.
CFL and LED options make good sense for task lighting – but if you want to be able to dim the light, you are better off going the LED route.
LED makes the most sense for exterior lighting and parking garages, as well as low temperature applications. But the return on investment (ROI) is just not there for overhead LEDs. Someday it will be, but that day hasn’t yet arrived.
Sometimes we have clients that intentionally want to be over-lit. We’re working with a firearms manufacturer in New England right now. They make weapons for law enforcement, and they have no interest in lighting to building code; in fact, they wanted double the maximum allowable lighting, so we had to go for a variance. But they are the exception, not the rule! So if you are not performing surgery in your office, or assembling firearms so police can keep us safe, maybe it makes sense to throttle back the amount of lighting you’re using!
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