10th largest plant in Maryland · 753rd nationally
Perryman is a natural gas power plant in Maryland with a nameplate capacity of 492 MW. It generates roughly 246.9k MWh per year — enough to power about 23,510 average U.S. homes.
Its capacity factor of 6% reflects intermittent or peaking operation. At 1363 lb CO₂/MWh, its emission rate sits above the national grid average of roughly 800 lb/MWh.
| Plant Name | Perryman |
|---|---|
| Operator | Constellation Power Source Generation, Llc |
| City | Harford County |
| County | Harford County |
| State | Maryland |
| ZIP | 21130 |
| Coordinates | 39.44284, -76.22176 |
This plant highlighted in navy-ringed pin; other generators within 25 miles shown as fuel-colored dots.
| ID | Technology | Fuel | Capacity | Status | Online |
|---|---|---|---|---|---|
| GT5 | Natural Gas Fired Combustion Turbine | Natural Gas | 192 MW | Operating | 1995 |
| GT6 | Natural Gas Fired Combustion Turbine | Natural Gas | 141 MW | Operating | 2015 |
| GT1 | Petroleum Liquids | Distillate Oil | 53.1 MW | Operating | 1972 |
| GT2 | Petroleum Liquids | Distillate Oil | 53.1 MW | Retired | 1972 |
| GT3 | Petroleum Liquids | Distillate Oil | 53.1 MW | Operating | 1972 |
| GT4 | Petroleum Liquids | Distillate Oil | 53.1 MW | Operating | 1972 |
| CO₂ | 168.2k metric tons |
|---|---|
| SO₂ | 1 metric tons |
| NOₓ | 65 metric tons |
| CO₂ Rate | 1363 lb/MWh |
Annual totals and CO₂ rate reported by EPA eGRID for 2023. Reference averages are approximate U.S.-wide figures from the same dataset.
| NERC Region | RFC |
|---|---|
| Balancing Authority | Pjm Interconnection, Llc |
Natural gas plants are the workhorse of the modern grid. Combined-cycle units achieve very high efficiency and can ramp up and down quickly to balance variable renewables. They emit roughly half the CO₂ per MWh of coal and far less of other pollutants, but they still release upstream methane during fuel extraction.