By Jeff Carpenter, PE, RCDD
Low-voltage systems can contribute to sustainability.
When thinking about sustainable concepts on projects, low-voltage building systems are likely not the first thing that comes to the mind. The initial focus is typically on architectural issues, electrical and mechanical system considerations, natural lighting, and other more commonly considered concepts. But low-voltage building systems can support sustainability, even to the point of providing LEED points on a project.
First, the easy initiatives.
Relatively recent code requires that abandoned low-voltage cable be removed from buildings. This requirement helps to support recycling. The benefits of recycling don't need to be further explained here; they are second nature in today's world. At least one company has developed a program for this purpose. DuPont has developed a closed-loop recycling program called DuPont Abandoned Cable Services. This initiative provides LEED credits for participation in the program. A waste management plan can be developed to outline how low-voltage cabling waste will be diverted from traditional landfill or incineration disposal.
Now for the broader design concepts.
Each client's project has defined low-voltage and operational requirements. Are there sustainable considerations in how we meet the client's defined objectives? Absolutely. Consider a design approach that reduces the amount of material necessary to meet the defined objectives. Consider also a design approach that lengthens the useful life of a portion of the materials installed, thus further reducing, over time, the amount of material required.
Both of these considerations can be met using a design concept we'll call the "Technology Utility" (TU). The TU is a shift in focus, recognizing the benefits that technology convergence has provided us. You may be familiar with the concept of a structured cabling system in the IT world. The structured cabling system provides an infrastructure that "all that is IT" could leverage. Think of the TU as an expansion of the structured cabling system concept. The TU provides an infrastructure that "all that is low voltage" can leverage. There are many benefits to this approach beyond sustainability. However, the sustainability benefits are considerable on their own merits.
The TU and the selection of systems that can leverage it reduce the amount of redundant cabling necessary to support traditionally disparate systems. Consolidating all low-voltage systems to a common infrastructure also permits a more concise sharing of space (once thought of only as "IT closets"), which can consolidate required HVAC cooling loads into common, shared spaces. This increases the efficiency of cooling low-voltage equipment.
Perhaps the most significant benefit of the TU is a longer term consideration. The useful life of an "edge device" is typically 3 to 5 years. Let's define an edge device as a thing that we use and interact with (such as a computer, PDA, phone, projector). Prior to the concept of a technology infrastructure, with each edge device replacement cycle much of the cabling and other support materials necessary to support that edge device also had to be modified or replaced. This increased costs, waste, and materials use. The TU creates an infrastructure that, when designed correctly, can have a useful life of its own that is double the useful life of the edge device. When you eliminate the infrastructure work to replace edge devices, you've achieved measurable sustainability benefits. In addition, just imagine the benefits that exist outside the scope of a sustainability discussion.
Architecturally, this discussion matters because the TU cannot succeed without programming and planning for it as an integral part of the A/E process. The space planning, cost considerations, and affect on the client's operations are too integrated into the architectural considerations to unbundle technology as a completely separate activity, as was the standard approach not too many years ago.
The TU can provide great benefits and contribute to the sustainable goals of projects when fully integrated into the A/E process.
Jeff Carpenter is an associate/technology department manager at KJWW Engineering Consultants in Urbandale, IA.
