A 400 MW interconnection on paper is not 400 MW of delivered capacity. Once you subtract RICE NESHAP hour budgets, state BACT guidance like Virginia DEQ APG-576, and the curtailment frequency implied by a non-firm or interim non-firm transmission service agreement, the effective MW is often 20 to 30 percent lower. Most underwriting models do not price this. The developer finds out at ISA signature, or worse, at commissioning.
The Cliff de-rate calculator does this math per POI. Pick a state, pick a technology, enter the POI and the requested MW, and the calculator couples the RICE NESHAP annual hour budget, the state air-permit BACT hour cap, the Title V overlay if applicable, and the curtailment-product frequency implied by your interconnection class. The output is a single effective MW number with the math shown. Runs in under a second.
The math itself is arithmetic. What is AI-native is the input layer underneath. APG-576 is a guidance document, not a structured database. PJM’s non-firm product definitions live in tariff language that changes as FERC orders land. Five years ago a calculator that pretends to do this would have had to hire a regulatory team to maintain the assumptions. Today the assumptions update themselves from the same live docket corpus that Cliff’s regulatory intelligence layer ingests every day.
Run it on your own site at /de-rate/calculator, or read the walkthrough at /de-rate/how-it-works.
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Type your site in. See the de-rate.
The calculator returns an effective MW number, the binding rule, and a $/MW-yr net value as you type.