New Page on Launched To Visualize Marginal Emission Rates for the PJM Footprint

Marginal Emissions Graph Soon Also Available for PJM Now With Additional Updates To Come


PJM has launched a new page on that visualizes marginal emissions information for the region PJM serves.

The new Emissions page and marginal emissions graph reflect the marginal emission rates of carbon dioxide (CO2), nitrogen oxides (NOx) and sulfur dioxide (SO2). Marginal emissions are the emissions caused by producing the last megawatt of energy on the system serving customer load.

Any variations in the way the system is dispatched to maintain grid reliability may change the type of electricity resource serving this “last megawatt,” which in turn would change the marginal emissions accordingly.

The new graph can display marginal emissions data for the PJM footprint in two-, four-, eight- and 12-hour increments, pulling information from PJM’s Data Miner tool. This information is based on annually reported average data from electric generators within the PJM footprint. PJM does not receive real-time emissions data from plants.

The new marginal emissions graph is also available on the PJM Now app for iPhone and Android devices, with additional emissions-related graphs also to come in 2023 on both the emissions page on and PJM Now.