Analysis of Carbon Dioxide Emission Reductions From Energy Efficiency Upgrades in Consideration of Climate Change and Renewable Energy Policy Initiatives Using eQUEST

In January 2008 the Governor of Hawaii announced the Hawaii Clean Energy Initiative; an initiative that aims to have at least 70 percent of Hawaii’s power come from clean energy by 2030 [4]. In July 2009, the Hawaii Department of Accounting and General Services awarded NORESCO, an energy service company, a $33.9M contract to improve the energy efficiency of 10 government buildings. The avoided utility cost of the energy and water savings from the improvements is the project funding mechanism. The energy savings realized by the project will reduce carbon dioxide emissions associated with utility power generation. However, as renewable energy becomes a larger portion of the utility generation profile through the Hawaii Clean Energy Initiative, the carbon dioxide emissions reductions from specific energy efficiency measures may erode over time. This work presents a method of analysis to quantify the carbon dioxide emissions reduction over the life of a project generated by energy efficiency upgrades that accounts for both the impact of policy initiatives and climate change using DOE-2/eQUEST. The analysis is based on the fact that HVAC energy usage will vary with climate changes and that carbon dioxide emission reductions will vary with both energy savings and the corresponding utility’s power generation portfolio. The energy savings related to HVAC system energy efficiency improvements are calculated over the life of a 20 year performance contract using a calibrated DOE-2/eQUEST model of an existing building that utilizes weather data adjusted to match the predictions of the Intergovernmental Panel on Climate Change. The carbon dioxide emissions reductions are calculated using the energy savings results and a projection of the implementation of the Hawaii Clean Energy Initiative. The emissions reductions are compared with other analysis methods and discussed to establish more refined expectations of the impact of energy efficiency projects in context with climate changes and policy initiatives.