The problem
The hours that threaten adequacy are the ones where high demand and low supply coincide — a cold, still evening; a heat wave with derated thermal units. If demand and supply come from different assumptions, those hours are either missed or manufactured.
Coherent inputs
Demand scenarios (native load, electrification, large loads) and supply scenarios (renewables, conventional outages and derates, imports, storage, behind-the-fence generation) are drawn from the same weather and growth assumptions. Every hour of the balance is internally consistent.
Metrics
Probabilistic outcomes
Adequacy is reported as P10/P50/P90 outcomes across the 8760-hour scenario family, so planners can see how much of the risk comes from weather, from load growth, from the supply fleet, and from the assumptions that bind them.