Combined effects of policies to increase energy efficiency and distributed solar generation: A case study of the Carolinas

This paper estimates changes in the cost of electricity, reliability, and atmospheric emissions resulting from large penetration of residential roof-top Photovoltaic (PV) and end-use energy efficiency (EE) within the service areas of Duke Energy in the Carolinas, where nuclear power plants account for almost 50% of electricity generation. Results show that 8.7–10.2% of 2015 electricity consumption could have been avoided by upgrading all residential units to comply with Energy Star standards. The range for this estimate stems from uncertainty on whether, under business-as-usual conditions, most buildings comply with the 1978 or the 1996 energy building codes. These energy savings would have implied a reduction of 3–4% in the costs of running the current power generation fleet and a 9–11% reduction in CO2 emissions. If this level of EE had been paired with the installation of roof-top PV providing 6.1–6.4% of the total electricity generated, the costs of operating the system would have been reduced by 8.6–9.6% and CO2 emissions would have been 24–26% lower. This level of roof-top PV penetration is the maximum permissible under this EE scenario due to the reductions it causes to daily peak electricity consumption and the limited operational flexibility of the nuclear plants.

Duke Scholars

Author Dalia Patino-Echeverri Environmental Sciences and Policy