Alex A.C.
Value/GARP Investor, Semiconductor & Financial Analysis, Electronics MEng
Comfort Systems, MasTec and Quanta Services are hidden champions of the physical build-out behind AI data centers and US reshoring. Tech giants' data centers need massive cooling and electrical infrastructure, which Comfort Systems builds; it is up 500% from its lows. MasTec and Quanta build the power lines, water lines and pipelines for a factory boom funded by the Chips Act and Inflation Reduction Act. They rarely make headlines but are booked out for decades and quietly outperforming. x.comÂ
Comfort Systems USA remains a bullish holding, reaffirmed here with a shared link and no new argument. x.comÂ
HVAC's limited pricing power means Comfort Systems USA's margin expansion story is over. If supply and demand return to normal, operating margins could fall toward the historical norm of about 5%, from 16.5% in the latest quarter shown. x.comÂ
Comfort Systems' solid execution is a reason to hold despite a rich valuation, because selling a long-term winner on valuation alone rarely works. Long-term gains taxes of up to 37.1% in California mean the stock must fall a lot just to rebuy the same shares, and re-entry timing is uncertain. Some who sold it on valuation saw it rise 2-3x, so even a 50% crash would leave it above their exit. Only a material, lasting change in the long-term thesis justifies selling, not quarterly noise. x.comÂ
Comfort Systems USA is the more stable long-term holding than Vertiv, with an HVAC business available across the country and better fundamentals, so it merits about twice the position size, though both are worth owning. x.comÂ
Comfort Systems USA, a contractor installing HVAC and electrical systems inside AI data centers, trades at nearly twice Nvidia's forward earnings multiple, even though Nvidia's chips and CUDA ecosystem made the entire buildout possible. x.comÂ
Legence is a comforting company to own after a second quarter as a shareholder, a junior version of Comfort Systems USA in the portfolio. x.comÂ
Record data-center construction supports Sterling Infrastructure, Quanta Services, Comfort Systems USA, Vertiv and Argan. Per The Kobeissi Letter, US data-center construction spending jumped 46% YoY in June to a record $68 billion annualized rate, up 158% since January 2024, and now exceeds office construction by a record $25 billion. Kobeissi calls AI the driver of the biggest investment wave in US history. x.comÂ
ABB owns the supply in the transformer and switchgear shortage that is delaying 50% of 2026 US data centers, and its record Q1 order intake leaves the thesis intact. Equipment prices are up 77-95% since 2019, and management guided to a confident 2026 with customers planning ahead. Kepler raised its price target to CHF 80 even while downgrading on valuation. x.comÂ
AI infrastructure operators such as Core Scientific, CoreWeave, Galaxy Digital and TeraWulf benefit if out-year gigawatt projections are not met. Constraints on power generation, grid transmission, labor and wafer capacity limit how many debt-financed data centers and chips get built, which is healthier longer term if the build-out is funded from operating cash flow. @LEJCapital counters that this assumes demand keeps growing exponentially and stays far above supply. x.com x.comÂ