FRANKFURT — European and North American transmission operators executed binding procurement orders exceeding twelve gigawatt-hours of 100-hour iron-air battery storage this week to firm regional renewable grids.
Unlike lithium-ion arrays optimized for four-hour evening peaks, reversible iron-oxidation modules store energy across four-day weather lulls using abundant domestic iron pellets and ambient air.
Grid planners noted that colocating multi-day storage at retired coal substations accelerates interconnection timelines by reusing existing high-voltage step-up transformers.