inZOR-ND: 1.66× Faster Real-Time N-1 Grid Security Under Renewable Volatility — 132,480 Contingency Assessments on ENTSO-E Germany Q2 2025 Data

This study quantifies how a bio-adaptive warm-start strategy (inZORi) reduces the number of Newton-Raphson iterations needed for N-1 contingency power flow convergence under real renewable volatility. **Setup:** case1354pegase Pan-European benchmark network (1354 buses, 1991 lines, ~73 GW nominal). 8,832 sequential 15-minute intervals of real ENTSO-E generation data from Germany Q2 2025 (April–June). 132,480 N-1 contingency assessments (3 seeds × 5 random lines per interval). Identical tolerance (10⁻⁶ MVA) for both solvers. **Core Result:** inZORi converges in **3.15 iterations** on average vs Newton-Raphson's **5.22 iterations** — a **1.66× speedup** that translates to **1,058 vs 638 contingencies verified per minute**. The advantage is consistent from 0.90× to 1.31× load (the full physical operating range) and largest at normal operation (~1.99× at 0.92× load). **Key Findings:** - Global speedup: 1.66× (3.15 vs 5.22 iterations) - Iterations saved per contingency: +2.07 (mean) - Throughput gain: +66% more N-1 security checks per minute (1,058 vs 638 ctg/min) - Peak speedup: 1.99× at 0.92× load (normal operation) - Both solvers solve exactly the same 130,056 cases and fail on the same 2,424 (physical collapse at >1.31× load) - Advantage consistent across all renewable share levels (12%–91%) **Methodology:** Both solvers use identical Newton-Raphson mathematics (pandapower) and convergence tolerance (10⁻⁶ MVA). Only the starting strategy differs: NR uses flat-start (V=1.0, angle=0°), inZORi uses a genomically-evolved warm-blend (97.9% previous solution + 2.1% flat). The genome (memory_lr=0.979) was evolved using (μ+λ) evolutionary strategy on case1354pegase N-1 scenarios. **Practical Impact:** On a 2,000-line network, inZORi saves ~1.2 minutes per full N-1 scan. Over a 15-minute real-time cycle, this enables 3 additional complete security assessments — directly supporting EU renewable integration targets by maintaining grid security assessment speed as the generation mix becomes more volatile. **Limitations:** Results use case1354pegase benchmark topology, not real TSO network. Load scaling is uniform across all nodes. Real SCADA data not available for validation. **Related publications:** - Phase 1 (IEEE 118-bus, Proof of Concept): https://doi.org/10.5281/zenodo.18716837 - Phase 2 (Real AC Power Flow): https://doi.org/10.5281/zenodo.18717007 - Phase 3 (N-2 Contingencies): https://doi.org/10.5281/zenodo.18735120 - Phase 4 (Historical Blackouts): https://doi.org/10.5281/zenodo.18735099 - Phase 5 (ENTSO-E Real Load RO/DE/FR 2024): https://doi.org/10.5281/zenodo.18806567 - Phase 6 (Capacity Boundary case1354pegase): https://doi.org/10.5281/zenodo.18806643 https://dumitrunovic-svg.github.io/inZOR-ND/index.html