The Sierra Club's sixth annual Dirty Truth Report card has ranked Mississippi Power near the bottom of U.S. utilities for its environmental performance and cost management, assigning the company a 44 out of 100.
The utility scored poorly across all three metrics the Sierra Club uses to evaluate power companies. Mississippi Power is retiring coal plants too slowly, planning excessive natural gas capacity, and adding insufficient renewable energy to its grid. These failings have direct consequences for both consumers and the climate.
Mississippi Power serves roughly 190,000 customers across central and southern Mississippi. The state's utility regulatory environment historically favored fossil fuel infrastructure, and Mississippi Power's strategy reflects that legacy. The company continues to operate coal plants that cost more to maintain than new renewable alternatives would cost to build and operate, according to energy economics research from utilities analysts over the past five years.
The Dirty Truth Report grades utilities on specific, quantifiable standards. Coal retirement timelines matter because aging coal plants emit high levels of carbon dioxide and other pollutants while requiring expensive maintenance. Natural gas expansion matters because it locks in decades of continued fossil fuel burning, delaying the transition to zero-carbon energy sources. Renewable energy capacity matters because wind and solar installations have become the cheapest source of new electricity generation in most U.S. regions, including the South.
Mississippi Power's low score places it among the worst performers nationally. This contrasts sharply with utilities in states like California and New York, where aggressive decarbonization mandates and consumer pressure have accelerated retirements of fossil fuel plants and major renewable buildouts. Southern utilities have generally lagged behind regional peers in transitioning away from coal and gas.
The financial argument cuts both ways. Mississippi Power argues that maintaining coal plants preserves jobs and grid reliability. But independent analyses show that renewable energy paired with battery storage delivers both lower operational costs and greater system reliability than aging coal plants. Utilities that have accelerated renewable transitions, like Duke Energy in the Carolinas, have not experienced the grid instability their predecessors predicted.
Mississippi Power's parent company, Entergy, operates across multiple states and has committed to carbon neutrality by 2050 under its corporate goals. However, Mississippi Power's actual project portfolio does not align with that timeline. The utility has proposed new natural gas generation while maintaining its existing coal fleet, a strategy that extends the company's reliance on combustion-based power for decades beyond when economics and technology suggest alternatives should dominate.
Consumers pay the price. Mississippi Power's residential electricity rates rank among the highest in the South, yet the utility continues recovering costs for coal plant operations that provide minimal operational advantages over newer technologies. Solar and wind installations would diversify Mississippi Power's generation portfolio, reduce fuel cost volatility, and lower long-term customer bills.
The Sierra Club's report functions as a public benchmark. It names Mississippi Power and other low-scoring utilities while highlighting top performers. This transparency creates regulatory and reputational pressure on companies to accelerate their energy transitions. The Mississippi Public Service Commission, which oversees the utility's rates and operations, will likely reference the report in upcoming rate cases and capacity planning decisions.