Nuclear energy is gaining importance in the utility sector as rising electricity demand and clean-energy goals increase the need for reliable, carbon-free power. Unlike weather-dependent solar and wind resources, nuclear plants provide steady, around-the-clock electricity and require relatively less land for large-scale generation.
Against this backdrop, Constellation Energy Corporation CEG and Vistra Corp. VST stand out as major U.S. power producers with significant nuclear exposure.
Constellation Energy operates the largest nuclear fleet in the United States, with its plants maintaining an average capacity factor of more than 93%. The company’s nuclear assets provide dependable carbon-free electricity, while investments in clean hydrogen and energy storage further support its long-term growth strategy. Constellation Energy is expanding long-term clean-energy contracts with major customers. Its 15-year agreement with Walmart will supply nearly 176 MW of nuclear power from Dresden starting in 2029 and 2030, supporting uprates, grid reliability and long-term growth.
Vistra strengthened its nuclear portfolio through the 2023 acquisition of Energy Harbor. Its Vistra Vision subsidiary houses nuclear and other zero-carbon generation assets, positioning the company to benefit from rising demand for reliable clean power. Long-term PPAs remain central to Vistra’s strategy of expanding contracted earnings while retaining merchant exposure. Agreements with Meta and AWS should strengthen revenues, with some Meta-related benefits expected in 2027.
Both CEG and VST are well placed to capitalize on growing nuclear power demand. Let us compare their fundamentals, growth prospects and valuation to determine which stock offers the better investment opportunity.
CEG & VST’s Earnings Growth Projections
The Zacks Consensus Estimate for Vistra’s 2026 and 2027 earnings implies year-over-year growth of 75.1% and 14.01%, respectively.
Image Source: Zacks Investment Research
The same for Constellation Energy’s 2026 and 2027 earnings indicates year-over-year growth of 28.01% and 7.96%, respectively.
Image Source: Zacks Investment Research
Return on Equity
Return on Equity (“ROE”) is an important measure of financial performance that indicates how efficiently a company converts shareholder equity into profits. It highlights management’s effectiveness in utilizing invested capital to grow earnings and enhance shareholder value.
CEG’s current ROE is 14.89% compared with VST’s 108.68%.
Image Source: Zacks Investment Research
Nuclear Energy Generation Capacity
Constellation Energy has a total generation capacity of nearly 31,676 MWhs at the end of 2025, out of which 22,069 MWhs, or 69.7%, came from nuclear energy.
Vistra has a total generation capacity of 43,641 MWh at the end of 2025, out of which 6,448 MWh, or 15%, came from nuclear energy units.
VST’s Net Margin Higher Than CEG
Net margin measures the percentage of revenue retained as profit after deducting all expenses, taxes and interest.
VST’s net margin is currently pegged at 16.31% compared with CEG’s 11.39%.
Image Source: Zacks Investment Research
Valuation
Constellation Energy currently appears to trade at a premium compared with Vistra on a Price/Earnings Forward 12-month basis. (P/E- F12M).
CEG and VST are currently trading at 21.8X and 13.62X, respectively.
Image Source: Zacks Investment Research
Debt to Capital
The capital-intensive Zacks Utilities sector requires substantial investment to modernize infrastructure, expand operations and adopt new technologies. Utilities generally supplement internally generated cash with external borrowings to fund these projects.
Constellation Energy’s long-term debt-to-capital currently stands at 37.16% compared with Vistra’s 76.13%. Both companies are using debt to fund their business.
Summing Up
CEG and VST are major energy providers with substantial investments in clean and reliable energy generation, positioning them as key players in the clean energy transition.
Constellation Energy is currently using less debt than Vistra to run its operations. However, better earnings estimate movements, stronger ROE, a cheaper valuation and healthier net margin make VST more attractive.
Even though both companies currently carry a Zacks Rank #3 (Hold), based on the above discussion, it is evident Vistra currently has an edge over Constellation Energy and is likely to offer better opportunities for investors.
You can see the complete list of today’s Zacks #1 Rank (Strong Buy) stocks here.
Zacks' Research Chief Names "Stock Most Likely to Double"
Our team of experts has just released the 5 stocks with the greatest probability of gaining +100% or more in the coming months. Of those 5, Director of Research Sheraz Mian highlights the one stock set to climb highest.
This top pick is a little-known satellite-based communications firm. Space is projected to become a trillion dollar industry, and this company's customer base is growing fast. Analysts have forecasted a major revenue breakout in 2025. Of course, all our elite picks aren't winners but this one could far surpass earlier Zacks' Stocks Set to Double like Hims & Hers Health, which shot up +209%.
Free: See Our Top Stock And 4 Runners UpWant the latest recommendations from Zacks Investment Research? Today, you can download 7 Best Stocks for the Next 30 Days. Click to get this free report
Constellation Energy Corporation (CEG): Free Stock Analysis Report
Vistra Corp. (VST): Free Stock Analysis ReportThis article originally published on Zacks Investment Research (zacks.com).
Zacks Investment Research
