Twenty percent of US energy consumption and its consequential environmental effects is associated with the building sector. The residential housing market alone has a significant impact on US emissions. Residential retrofits have been identified as a key solution to reduce building energy consumption, without consuming a large portion of upfront embodied energy and generating consequential embodied carbon for a new building construction. While increasing home energy efficiency is a national goal, there has been only a limited number of homeowners who accept pursuing comprehensive home energy improvements. Even if they are accepted, it is often done in a “single-measure implementation” approach.
The objective of this research is to study residential buildings built over several years in the city of Atlanta and conduct comprehensive energy, cost, and carbon emission retrofit optimization analysis over a potential mix of improvements and technologies. The goal is to find the best multimeasure retrofit solution to minimize both cost and energy consumption, as well as environmental emissions. For this purpose, we have modeled Atlanta residential buildings built over decades using the Energy Performance Calculator (EPC) building energy modeling tool and conducted sensitivity analysis to find the best possible retrofit option while changing the cost and emission restrictions.
The preliminary results show that by decreasing the retrofit cost, the minimized delivered energy generally increased. The best cost solution is found when minimizing energy while keeping the retrofit cost lower than $30K. Results also indicated that improving the Heating, Ventilation and Air Conditioning (HVAC) system, windows, and building insulation have the greatest effects (approximately 60%) on reducing buildings’ energy consumption. The result of this research can be used by policy makers and city planners to implement the best development scenarios for the Atlanta metropolitan area while improving the sustainability and energy-efficiency of the nation.