When employing sustainable lighting strategies, financial benefits can be realized from several sources including energy savings from proper controls, efficient equipment and behavioral change, as well as increased productivity and reduced maintenance costs.
For a high-level overview, watch DOE Better Buildings' The Business Case for High-Performance Buildings.
With payback periods often less than one year, lighting projects offer some of the simplest measures when seeking to reduce energy costs. For example, a conversion from T-12 lamps to T-8s with electronic ballasts can save 35% on lighting energy . Savings can be even greater with LEDs. Daylighting strategies employ free light from the sun. Of course, lighting systems use the least energy when turned off. Occupancy sensors ensure that lights are off when no one is around, which can be most of the day in many applications. Efficient exterior lighting provides another great opportunity for savings.
An educational campaign for your staff can quickly pay for itself. Ask your employees to turn off the lights when leaving a room, particularly at the end of the day. Task lighting, often unconnected to occupancy sensors, should also be turned off. Consider asking your IT department to install a shut-down reminder on employee computers, a message that asks employees to turn off lights when headed home.
High-efficiency lighting tends to have very long life. Technologies like LEDs, which today have longer payback periods when considering energy alone, can look even more attractive when one considers the infrequency with which your maintenance staff will have to get up on the ladder. Group re-lamping, where multiple lamps near the end of their useful life are replaced at the same time, may help reduce maintenance labor costs. For more money-saving tips related to lighting-maintenance, see the Operations & Maintenance Impact sub-section.
Even though energy and maintenance are significant portions of an organization’s operating budget, these tend to be greatly outweighed by the cost of the workforce’s salaries and benefits. Better lighting can increase productivity (see the Human Impacts sub-section), and even small improvements in worker productivity or reductions in worker absenteeism can lead to significant financial gains. For a typical organization, an improvement in productivity of just 1% would offset lighting energy costs entirely.
Findings and Case Studies
Finding: LED downlight lamps for existing CFL ballasts can produce energy savings between 40-50%, matching light levels and quality, and have a payback of under 3 years. Source: GSA's Proving Ground | LED Downlight Lamps for CFL Fixtures
Finding: Savings of over 30% is possible in just one year.
Scope: 245 Buildings in the 2011 National Building Competition Source: EnergyStar.gov | National Building Competition: 2011 Summary
Finding: Occupancy sensors can save 15% to 20% on lighting energy costs. Source: ASHRAE.org | Advanced Energy Design Guide for Small to Medium Office Buildings
Finding: One lighting upgrade at a postal sorting facility in Reno, Nevada led to a 6% increase in worker output and a reduction in sorting errors.
Scope: Mail-processing center in Reno, Nevada Source: Rocky Mountain Institute | Romm, Jospeph J. and Browning, William D. “Greening the Building and the Bottom Line” (1994)
Did You Know?
Improvements in indoor environments are estimated to save $17-48 billion in total health gains and $20-160 billion in worker performance.
Courtesy: E Source; data from Right Light Consortium
According to the Right Light Consortium, salaries and benefits account for nearly 86% of annual operating costs per square foot in a typical office space. As a result, even small improvements in worker productivity or reductions in worker absenteeism can lead to significant financial gains, with only a 1% productivity savings offsetting a company’s entire annual energy cost.
Be sure to buy ENERGY STAR qualified Compact Fluorescent Lamps (CFLs) and LEDs. ENERGY STAR qualified CFLs will save approximately $30 or more in electricity costs over each bulb’s lifetime; LEDs will save even more.