When the Grid Feels the Heat: Transient Stability in Low-Inertia Power Systems

As some parts of the world face record-breaking temperatures and electricity demand peaks, the grid is under more pressure than ever. But this spike in demand isn’t just seasonal—it’s a real-time stress test for a system that’s already going through massive change.

With more inverter-based resources (IBRs)—like solar and wind—replacing conventional generators, the grid is steadily losing something it once relied on: inertia.

In traditional power systems, large rotating machines act like the reflexes of the human body—responding instantly to disturbances and keeping everything balanced. Inertia in that context acts like a cushion, absorbing shocks and buying a few precious seconds to stabilize the system before things spin out of control.

But in today’s grids, where renewables and IBRs dominate, those natural reflexes are fading. The result? A system that’s slower to respond, more fragile under stress, and increasingly sensitive to sudden faults or load shifts.

As part of our latest green hydrogen initiative, the Go2Power team explored how to boost the stability and flexibility of a microgrid by simulating different scenarios using a digital twin—tailored to reflect real-world power system constraints.

 Our model included:

• 4 GW of solar generation

• 4 GW of wind power

• 700 MW of battery storage

• 250 MW of internal combustion engine generators

• Sensitive loads, including a 3.5 GW hydrogen electrolysis facility

Here are some of the ways we explored to improve transient stability in a system with little or no traditional inertia:

• Battery Energy Storage Systems (BESS) + Grid-Forming Inverters (GFM): These inverters don’t just follow the grid—they create it, setting their own voltage and frequency references. With advanced droop control and adaptive Q–V tuning, GFM-enabled BESS can intelligently share power and help maintain voltage, even in weak grids.

• Synchronous Condensers: While they don’t supply active power, their spinning mass provides real inertia and fault current contribution. Often repurposed from retired generators, they’re a practical, cost-effective way to strengthen system stability.

• Grid-Forming STATCOMs (and E-STATCOMs): By combining reactive power support with energy storage, these systems offer low O&M costs and virtually no environmental impact—especially valuable in grids that prioritize sustainability.

• Supercapacitors: With ultra-fast discharge and minimal footprint, supercapacitors can respond in milliseconds—perfect for fast frequency response (FFR) and short-term stabilization in low-inertia systems.

• Smarter Control Schemes: Enhanced phase-locked loop (PLL) algorithms allow inverters to more accurately “lock onto” the grid, which is essential in weaker or more dynamic networks.

As climate extremes become more common, the way we approach system stability has to change just as quickly. Renewables are here to stay—but without matching that transition with smarter infrastructure, the grid becomes vulnerable at the worst possible time.

Whether it’s grid-forming inverters, condensers, or something entirely new, the key is engineering resilience, adaptability, and speed into every layer of the system.

The heat wave will pass—but the urgency to modernize our grids won’t. As the Northern Hemisphere enters another long, hot summer, just a kind reminder: don’t forget your sunscreen—and let us handle grid stability.