SPP

FERC issued SPP a Section 206 show-cause order on 18 June 2026 alongside all five other US Regional Transmission Organisations, requiring it to justify or reform its large-load tariffs across five areas including co-location terms, study processes, and cost allocation. SPP's response is due 17 August, public comments 16 September, and any binding national standard is deferred to 2027 at the earliest.

SPP (Southwest Power Pool) operates the high-voltage transmission grid across 14 US states in the central Plains, from North Dakota to Oklahoma, including Nebraska, Kansas, and Missouri. It is a non-profit, member-owned organisation: its members are the utilities it interconnects rather than independent investors. SPP manages one of the fastest-growing renewable energy corridors in the country, with substantial wind generation capacity in Kansas and Oklahoma that has attracted data-centre interest from operators seeking lower-carbon power mixes at competitive prices.

SPP's show-cause response carries strategic weight for data-centre developers considering whether to route builds from ERCOT-adjacent Texas into the SPP footprint. The Plains corridor offers wind power at competitive prices and avoids ERCOT's 438 GW interconnection queue, but SPP's own large-load backlog has grown as operators followed that logic. FERC's six separate show-cause orders mean SPP can tailor its reform response to its member-owned structure, which differs from the investor-owned or government-owned RTOs elsewhere.