The 66 GW AI power headline is a forecast with a missing bill

Goldman Sachs estimated in May that U.S. data-center power demand could rise from 31 gigawatts in 2025 to 66 gigawatts in 2027. The pace would be extraordinary, but the number is a forecast, not a 2027 meter reading. It assumes capacity expansion, about 70% utilization, and adjustment for delays. Goldman's own analysis says only about half to three-fifths of scheduled capacity over the next one to two years may arrive on time. It also warns that impacts will vary by region. Some power markets have little generation planned relative to prospective data-center load; others may absorb more. That distinction is what a household needs, not a national headline alone. A proposed campus can enter a planning queue long before it is powered, and overlapping applications may not become separate buildings. Yet utilities must decide how much generation, transmission and distribution capacity to prepare in advance. The cost can materialize before the forecast does. Electricity planners should publish project-level milestones and who pays for dedicated upgrades if a large load is delayed, scaled down or cancelled. This is not an argument against data centers or new power supply. It is an argument against asking ordinary customers to underwrite speculative capacity without a transparent allocation. The measured outcome to watch is commissioned load and actual tariff treatment, not a rendered campus or a single megawatt projection.