Sierra Club attorneys are advocating across the country to shield residential customers from exorbitant increases to their utility bills caused by the artificial intelligence (AI) boom. The growth in AI has created increased demand on the electric grid, particularly from the data centers powering it. This issue is being negotiated in public utility commissions nationwide, where commissioners are grappling with how this increased demand, or large load growth, will shape not only electric customer utility bills but also the energy sources needed to power the increased demand. Some utilities have proposed to keep fossil plants slated for retirement online and to build new gas-burning power plants, a decision that will impact public health for decades to come. As a result, Sierra Club has been advocating for large load tariffs to help quell data center speculation and customer bill impacts while also advancing aggressive renewable energy growth. Here's a primer on the topic: at its simplest, a large load tariff sets the rules for large customers that seek to connect to a particular utility’s grid.
In Fall 2025, Sierra Club shaped two tariffs governing (1) how large loads pay for electricity, and (2) how they access clean energy in Evergy's service territory. Evergy, the largest electric utility in Kansas and second-largest in Missouri, anticipates unprecedented load growth—more than double its existing load—primarily from data centers. The tariffs protect energy consumers by ensuring that large load customers pay for the additional costs they impose on the electric system without shifting those costs to other customer classes, like residential customers already squeezed by the affordability crisis. The tariffs also insulate Evergy from stranded asset risk—i.e., building (mostly) gas-burning power plants to serve data centers and then being left with the bag if the AI boom ends up a bust.
Critically, the adopted tariffs in Kansas and Missouri—due directly to Sierra Club’s advocacy–provide a renewable pathway to power data centers with clean energy. Large load customers will now have an ability to use Evergy’s existing resource planning process to procure clean energy, which can stabilize and even drive down utility costs for non-large load customers through diversification of electric generation. Sierra Club will continue to engage in resource planning and advocate for large customers to utilize the clean energy options now available to them.
Sierra Club was represented in these matters by in-house counsel, Senior Attorneys Sunil Bector and Tony Mendoza, with support from Research Analyst Ashley Soliman and in-house expert, Jeremy Fisher, Sierra Club's Principal Advisor for Climate and Energy.