Global renewable zone classification to map deployment constraints and opportunities

<title>Abstract</title> <p>The global energy transition requires an unprecedented scale of wind and solar power deployment across diverse geographies. The time-variability and location-dependence of renewables mean that achieving deep decarbonisation through very high renewable shares raises more difficult challenges than those faced so far. Addressing them will require location-specific strategies, yet most studies examine only a few wealthy regions or disparate aspects, leaving the global picture fragmented and at risk of lock-in to suboptimal build-out. Here we show that constraints on wind-solar-only deployment are recurrent worldwide, identified with a unified global renewable zone classification in analogy to the Köppen–Geiger climate zones. Land that is abundant in both resources and temporally reliable is scarce; long-duration storage is a nearly universal requirement; demand centres are systematically misaligned with the best resources, a legacy of dense settlement in fertile, sheltered valleys whose topography suppresses generation; and these patterns are not reducible to climate. Grouping countries reveals four distinct deployment groups with frontrunners whose strategies may transfer to similar countries. Our globally consistent classification offers a shared reference across the energy, climate, geography, and policy communities, facilitating knowledge transfer among regions that face similar constraints.</p>