The Section 206 show-cause orders FERC issued on June 18, one for each of PJM, MISO, SPP, CAISO, ISO-NE, and NYISO, have moved from headline into procedural work. The July 9 intervention deadline closed last week. The next hard date is July 20, when each RTO and ISO must file a resource adequacy informational report describing what large loads mean for capacity, planning reserves, and near-term reliability under current tariffs. Substantive show-cause responses, including proposed tariff revisions where filings concede a gap, are due August 17. Stakeholder comment on those responses runs through September 16.
The five reform categories the Commission listed give the shape of a federal large-load regime rather than a rulemaking-in-name-only. First, application and study processes for large-load transmission service. Second, cost transparency and cost-shifting protections between large loads and existing customers. Third, terms and rates for co-location arrangements where load sits alongside dedicated generation. Fourth, treatment of flexible large loads and behind-the-meter generation services. Fifth, rates and conditions for what the Commission calls “electrically proximate” large load interconnection, meaning load sufficiently close to generation that a full transmission upgrade path is not the right frame. The orders illustrate proximity with a “no more than two substations away” example but stop short of a numeric threshold.
Two elements are worth watching in the July 20 filings. One is how each RTO characterizes its current large-load pipeline in gigawatt terms, because that number will anchor every downstream capacity and planning-reserve debate. ERCOT’s own June disclosure of 226 GW of large-load requests already set the scale of what a normalized federal accounting could reveal in other footprints. Two is whether any RTO uses the July 20 report to concede that its current tariff cannot address one or more of the five categories on its own, which would preview an August 17 filing of substantive tariff changes rather than a defense of the status quo.
Supply-chain read-through. The August 17 filings are the first opportunity to see what a co-location and behind-the-meter regime looks like in filed-tariff language across multiple RTOs at once. That language determines whether the marginal hyperscale gigawatt continues to route around the public grid via bilateral deals at existing nuclear plants and gas peakers, or whether uniform federal terms compress the negotiation surface enough to pull large loads back into the standard queue. The nuclear-for-data-center procurement stack, roughly 9.8 GW of announced hyperscaler commitments across SMR and restart deals, is priced today assuming the workaround remains the fast path. If August 17 filings signal a durable federal regime, that assumption resets.