PJM Interconnection, LLC - the company that manages the electricity grid in all or parts of 13 states and the District of Columbia - has found that raising renewable energy to 30 percent of the electricity supply can reduce CO2 emissions by 40 percent - while maintaining the reliability ofthe electric system.
PJM conducted a comprehensive study of the operational, planning, and market effects of large-scale integration of wind and solar power in its service territory (details here). The study’s Executive Summary says that the PJM system “will not have any significant issues operating with up to 30% of its energy provided by wind and solar generation.”
In this must-read blog post, the Union of Concerned Scientists’ Mike Jacobs explains the CO2 reduction potential of this shift to renewable energy:
The PJM scenario with greatest CO2 reduction is 30 percent renewable energy, using the best sites for wind, including a low amount of offshore wind, and one-sixth of the renewable energy coming from solar. The CO2 emissions change from over 500 million tons in year 2026 when running the grid as usual, to a new level of 300 million tons with this addition of renewable energy. That is a 40 percent reduction.PJM’s study represents the gold standard for this kind of analysis. As Jacobs notes, it shows the way forward to other grid operators and to states in the PJM region on meeting new Federal power plant emission standards. It should also propel those states to significantly increase their renewable energy requirements to get to 30% renewables as rapidly as possible - and then go beyond it.