Economic and GHG Emission Analysis of Implementing Sustainable Measures in Existing Public Buildings

Buildings in the United States are responsible for 72% of the nation's electricity consumption, 39% of energy consumption, 39% of carbon dioxide emissions, and 13% of potable water consumption. These significant energy and water consumptions and their carbon emissions contribute to global warming, ozone depletion, and air pollution. To reduce these negative impacts of buildings and improve their economic performance, there is an increasing demand for integrating sustainable measures in public buildings such as energy-efficient lighting; motion sensors for interior lighting; motion sensors for lighting of vending machines; motion sensors for exhaust fans; solar daylight tubes; energy-efficient HVAC systems; thermal-pane glass; vestibule entrances; energy-efficient hand dryers; solar photovoltaic systems; and water-saving toilets and urinals. Despite the recent increase in the availability of these sustainable building measures and technologies, there is a pressing need to analyze the economic and greenhouse gas (GHG) emission effects of implementing these measures in existing buildings. This paper presents an economic and GHG emission analysis of implementing various sustainable measures in six highway rest area buildings. The economic analysis was performed based on the initial upgrade costs, maintenance costs, operational costs, energy and water savings, discount rate, and escalation in energy rates. The GHG analysis was conducted based on the generated building emissions of carbon dioxide, nitrous oxide, and methane. The findings of the conducted economic and GHG emission analysis showed promising results with feasible implementation and return on investment for various sustainable-building measures. In addition, the implementation of all the analyzed measures in all rest area buildings simultaneously showed promising return on investment with payback periods ranging from 6.9 to 11.3years. The findings of this research paper can aid decision-makers and building owners to estimate the costs and benefits for implementing various sustainable-building measures in public buildings, as well as to prioritize the implementation of these measures based on their available budgets, reduction in operational costs and GHG emissions, and payback periods.