A Triple-Bottom-Line Analysis of Energy-Efficient Lighting

Abstract

Lighting trends worldwide are shifting toward greater energy efficiency as incandescent light bulbs are being discarded in favor of higher efficiency compact fluorescent lights (CFLs) and light-emitting diodes (LEDs). As energy-efficient lighting becomes the new norm, payoffs are likely to be seen through reductions in utility bills, energy consumption, pollution, and greenhouse gas emissions. These changes in lighting practices can be used as a framework for students to explore the larger concepts of energy use, energy efficiency, environmental impacts, and sustainability. The activity described in this chapter situates this exploration within the context of the university campus by having students evaluate the sustainability of a campus lighting project using the model of the triple bottom line. Students calculate the payback period of a lighting project, estimate the effects on associated carbon dioxide (CO₂) emissions, and reflect on the societal impacts of the lighting project in particular and of energy efficiency in general. After completing the activity, students should be able to (1) compare and contrast the energy efficiency of incandescent, CFL, and LED light bulbs; (2) calculate the costs over time and payback periods for using different models of light bulbs; (3) estimate the CO₂ emissions attributed to electricity use for lighting; (4) describe the relationship among energy use, economic costs, and CO₂ emissions; and (5) apply the triple-bottom-line perspective to lighting choices and to decision-making on personal and institutional levels.