Lighting the Way to Energy Savings
Last year Pennsylvania adopted a comprehensive statewide Building Code. Like many states, Pennsylvania opted to adopt the family of ‘International Codes’ written by the International Code Council. As part of this family of codes, which includes the International Building Code, International Mechanical Code, and International Plumbing Code, Pennsylvania also adopted the International Energy Conservation Code (IECC).
Energy Conservation Codes are relatively new codes, when compared to traditional building codes, and design professionals are still adapting to their requirements. The goal of this article is to review some of the requirements of the electrical portions of the 2003 IECC. While the electrical sections of the IECC consume about only three pages in a manual that is over 200 pages in length, they are causing a ripple throughout the design community.
“Fundamentally, the code encourages good design practices that promote efficiency and should always be followed…”
Fundamentally, the code encourages good design practices that promote efficiency and should always be followed: carefully matching the lighting levels to the task (i.e. not overlighting), limiting the use of incandescent lamps, and selecting the most energy efficient products, such as electronic ballasts.
However, as the code is designed for commercial buildings, it does not account for the specific and varied lighting requirements inherent to certain building types. An example is the lighting needs of skilled nursing care. The energy code specifies the maximum wattage allowed by type of indoor space. The code allows a dining room to be designed to 0.9 watts/square foot. Hallways and support spaces are also allowed 0.9 watts/square foot. While sufficient for typical commercial buildings, these allowances may be insufficient in senior care facilities to create the level of illumination necessary for older eyes. In these cases, engineers must work with local code officials to find an acceptable, yet energy efficient, solution.
Another part of the code designers must react to is the implementation of improved lighting controls. The new code mandates the maximum area of lighting control zones and requires automatic control of exterior building and site lighting. The code also requires that all buildings over 5,000 square feet be provided with either time-of-day controls or with occupancy sensors to shut off lighting when the spaces are not in use. In most designs, occupancy sensors are the most direct solution in meeting this requirement. However, they come with a cost. On a recently bid 160,000 square-foot secondary school in central Pennsylvania, $87,000 of the $2.9 million electrical bid was attributable to the new code requirements. This 3% increase was due to the new requirement for automatic lighting controls throughout the building. Though Owners might balk at having to absorb this cost, the resulting energy savings ultimately lead to reduced long-term operating expenses.
While we are all adjusting to the terms and requirements of the International Energy Conservation Code, we must remember that the goal of this code is to control energy consumption and limit pollution, goals which benefit us all.
– James A. Hackman, PE, LEED AP
Jim is a Senior Principal, Licensed Electrical Engineer, Lighting Designer, and LEED Accredited Professional. Please feel free to contact Jim for further details regarding the above information.