Hydrogen Cost Forecasts May Be Measuring the Wrong Kind of Doubling

Clean energy analysts have long relied on experience curves to forecast future costs. The basic idea is straightforward: as cumulative production of a technology doubles, its cost tends to drop by a consistent percentage. Apply that rate to the doublings still ahead, and you get a rough picture of where prices are heading. It has worked well for solar panels and batteries, and now many forecasters are applying the same logic to hydrogen electrolyzers.

The problem, according to a growing critique, is that the doublings being counted may not be the ones that actually drive cost reductions. Electrolyzer manufacturing and electrolyzer deployment are not the same thing, and plant-level scale-up introduces engineering, permitting, and integration challenges that a simple cumulative-output curve does not capture. If the learning rate is calculated from the wrong variable, the resulting forecast can look precise while resting on a shaky foundation.

This matters because hydrogen is often presented as a cornerstone of decarbonization plans for industry, shipping, and heavy transport. If the cost trajectory is built on a misapplied model, policymakers and investors could be planning around numbers that never materialize. The takeaway is not that experience curves are useless, but that they need to be matched carefully to the mechanism actually producing the savings, whether that is factory volume, project size, or something else entirely.

For now, the debate is a reminder that clean energy forecasting is only as good as its assumptions. Hydrogen may still get cheaper, but the pace will depend on which levers are pulled, and on whether analysts are measuring the right ones.