We found that the same exact query, with the same exact energy demand, will have a very different climate impact depending on what the data center is powered by, and that depends on the location and the time of day. For example, querying a data center in West Virginia could cause nearly twice the emissions of querying one in California, according to calculations based on average data from 2024. There is still so much that we don't know when it comes to AI and energy. But ultimately, we still have no idea what many of the biggest, most influential models are adding up to in terms of energy and emissions. This article is from The Spark, MIT Technology Review’s weekly climate newsletter.