Home Energy Management Stairwell Lighting: An Area of Opportunity to Reduce Energy Costs

Stairwell Lighting: An Area of Opportunity to Reduce Energy Costs


NATIONAL REPORT—When looking for ways to green your hotel, one of the first things you should focus on is energy efficiency. Pure economics show it is cheaper to save a kilowatt hour then it is to produce it. Couple this with reduced carbon emissions, and efficiency is one of the first things a property should consider, even before looking at renewable energy sources.

The first energy conservation measure that should be evaluated in hospitality, whether it is a small 100-room property or a large destination resort, is lighting. Common lighting opportunities include T-12 to T-8 or super T-8 linear fluorescent lighting retrofits in back-of-house applications, compact fluorescents in guestrooms and downlight cans, and cold cathode lamps for ballroom lighting. Until recently, stairwell lighting wasn’t looked at as an energy conservation measure by energy services companies and facilities managers alike.

Stairwells never represented a significant opportunity because they are required to be lit 24 hours a day, 7 days a week. Typically the solution for these types of areas would be a simple T12 to T8 retrofit. Occupancy sensors that would completely shut off the lights when the space was empty were not a consideration as this would violate safety and fire codes. As a result, stairwell lighting was bypassed when evaluating energy savings opportunities.

Significant Energy Savings

The solution to this unique application is bi-level lighting which maintains minimum illumination requirements when the stairwells are empty, thereby maximizing energy savings. Bi-level lighting fixtures have an ultrasonic sensor integrated into the fixture that dims the lighting down to minimum standards—as low as 10 percent of normal output—when no one is present. When the fixture detects someone in the area, the lighting is restored to full brightness. This can result in 50 to 80 percent energy savings per fixture replaced. Most occupants don’t even realize that the lights are motion sensor controlled, or that the light levels have changed.

The significance of the savings potential coupled with high energy costs in Hawaii make this an attractive market for bi-level lighting. Six installations were analyzed to determine savings potential. These installations consisted of two high-rise office buildings, three hotels, and one hospital. In most of these installations, the standby light levels were reduced to 10 percent in non-occupied mode to maximize the savings.

The stairwells in the hotel proved to be the least occupied, averaging between 1 to 3 percent. This varied based on the number of floors at the hotel as well as what floor was being monitored. Lower floors of the hotel had slightly more occupancy than the higher floors. The hospital had the highest occupancy of about 7 percent, mainly because many of the nurses used the stairs when traveling only one floor. The two office buildings were in the middle, averaging 2 percent occupancy.

The most significant savings was realized in one of the hotel applications where existing 2 lamp 40-watt T 12 lamps and magnetic ballasts were replaced with a 2 lamp bi-level fixture containing 2 lamp T8s. With 50 fixtures replaced, this amounted to an annual energy reduction of around 37,000 kilowatt hours for an annual energy savings of just over $5,000 or about $100 per fixture. This represents a 78 percent savings from the installation of the bi-level lighting fixtures.

Guests Not Impacted

This data proves the hospitality market is a prime candidate for this technology. Because stairwells are seldom used by guests, this technology doesn’t affect the guest experience, especially because the fixtures return to full brightness when the space is occupied.

In addition to the significant energy savings realized from the implementation of bi-level lighting, this type of project can qualify for a rebate from the local utility. The Energy Policy Act of 2005 allows for a tax deduction on these installations. One installation at a hotel on Waikiki Beach that combined this technology with other energy conservation measures was awarded the Energy Star Building Label from the EPA. The Energy Star Label can provide up to 10 points for Leadership in Energy and Environmental Design certification.

By including the battery backup in these fixtures, it also ensures that the emergency lighting will be available if there is a power outage even if the fixtures were not on an emergency circuit. After the October 2006 earthquakes in Hawaii, many hotels quickly discovered that some of the stairwell lighting was not on emergency circuits as previously believed. Hotel employees used glow sticks to help guests through the stairwells while the elevators were not operable during the power outage. The battery backup feature has increased the interest in these bi-level fixtures as it is now not only providing energy savings but also curing health and safety issues.

Given the success of the technology and Hawaii’s high energy costs, bi-level lighting will soon become the standard fixture for hotels and condominiums. Tax deductions and increasing energy costs also makes this technology appealing for all stairwell applications across the country. There are very few energy conservation measures that offer between a 50 to 80 percent reduction in energy usage, which makes bi-level lighting an exciting opportunity for you to reduce your carbon footprint. With ROIs like that, how can you afford not to do it?

Brian Kealoha, CEM, CLEP, is senior vice president of Energy Industries, LLC, a Hawaii-based energy services company with offices across the United States. He can be reached at brian.kealoha@energy-industries.com.