S&P 500 power stocks soar 11-13% on Google's nuclear deal and a $4.2B DOE loan

Three of the S&P 500's biggest gainers on Tuesday had nothing to do with chips or software. Vistra jumped 10.8% to close at $160.50, Constellation Energy surged 12.3% to $300.40 and NRG Energy added 7%, while Talen Energy — outside the index but squarely in the trade — ripped 12.4% higher to $373.11. Two nuclear-sized headlines drove it all within 24 hours. On Monday, the Energy Department offered Vistra a conditional loan commitment that could reach $4.2 billion for modernizing its nuclear fleet. On Tuesday, Constellation announced a 20-year agreement with Google to lift generation at 11 of its reactors, committing more than $4.3 billion of its own capital to the upgrades.

Energy Secretary Chris Wright unveiled the financing during a tour of Vistra's Perry site in Ohio. The package targets power uprates at Vistra's existing fleet in Ohio and Pennsylvania — the Perry, Davis-Besse and Beaver Valley stations — with an option to extend the program to Comanche Peak in Texas later. Two concrete targets were named: keep nearly 4 gigawatts of always-on baseload generation running, enough to supply over three million households, and add 433 megawatts of brand-new nuclear capacity across the 13-state PJM grid. Money only flows if milestones are met — the commitment is conditional — but investors read it as the first real federal check behind the administration's nuclear revival push. Vistra had already gained 3.5% on Monday's news; Tuesday's move extended the breakout, retaking the stock's 200-day moving average after that line had capped it since February.

The Constellation agreement attacks the same bottleneck from the private side. Under the 20-year arrangement announced Tuesday, Constellation will spend more than $4.3 billion on fresh hardware and systems at 11 reactors in the Midwest and Northeast — Illinois, Pennsylvania, New Jersey — unlocking roughly as much additional electricity as a brand-new reactor. Google will pay a set rate for the power its data centers use while the plants stay connected to the wider grid — a structure designed to keep new data-center load off household electricity bills, the political flashpoint that has dogged power markets all year. At the deal's core sits an 890-megawatt supply contract, the largest yet built around squeezing more electricity from existing reactors, according to the Journal. Constellation's stock reclaimed both its 50- and 200-day moving averages on the news.

For the index crowd: the S&P 500 itself closed at 7,819, up 0.58%. Vistra's single-day gain was roughly 19 times the index's — when three independent power producers rank among the day's top large-cap winners, that is a breadth story, not a stock story.

Why it matters

Power stocks have been 2026's pain trade. Fast-rising electricity bills turned data centers into a political target, regulators tightened the rules on who pays for new capacity, and the sector spent months in the dumps while the rest of the AI complex ran — Barron's notes these names were all down double digits on the year before Tuesday. The AI buildout keeps colliding with a physical limit: the grid. Hyperscalers can finance data centers, but the electrons have to come from somewhere, and a brand-new reactor takes a decade to permit and build. What broke the logjam was a two-front solution to the same problem: federal money de-risking Vistra's upgrades on one side, and a buyer template on the other showing hyperscalers will pay for firm nuclear power without raising rates for households. Tuesday's rally was the sector's sharpest single-session move in months, and small modular reactor names like Oklo rocketed alongside the incumbents — though the speculative SMR end of the trade remains far below its highs.

The move also shifts the AI trade's center of gravity away from the chipmakers. With the Nasdaq at 27,600 and the S&P 500 holding its record, the benchmark's gains are increasingly being shared with the companies that keep the servers lit — a rotation worth watching for anyone tracking US equity breadth. See our indices hub for ongoing coverage of the US benchmarks.