Grid Expectations: Americans' Overestimation of US Data Center Electricity Use

Data centers have become a controversial part of American culture, in part because of the massive amounts of electricity required to run them. But we know surprisingly little about how much the public understands the scale of their electricity use. In a preregistered survey of a Prolific sample recruited to mimic US demographics (N = 303 after preregistered exclusions), respondents estimated the share of US electricity used by data centers today and in 2030.

The median current estimate was 20%, compared with a reported benchmark from Lawrence Berkeley National Laboratory of 4.7% for 2024. Ninety-two percent of respondents' estimates exceeded that reported benchmark, and 63% put current use at or above LBNL's 11.8% Reference Case for 2030. All four preregistered tests supported the predicted directions, with large rank-biserial effects; the results were unchanged by winsorization and remained strong when the preregistered exclusions were removed.

Two exploratory patterns deserve replication. First, women's median estimate was 30%, versus 11% for men, with both groups having a vast majority of respondents above the benchmark; the gap remained after adjustment for age, politics, ethnicity, information source, and self-stated confidence. Second, confidence ran backward: the least confident guessers were the most accurate group, while the four very-confident respondents missed by a median of 65.8 percentage points.

Political affiliation showed no detectable association with current-use estimates in this sample.