The Iron Law of Technology holds that a technology becomes useful only when its future promise becomes current practice — and by that measure, solar, wind, and lithium-ion batteries remain incomplete solutions. Despite decades of subsidies and policy preference, these renewables cannot solve the climate problem without three additional technologies that are themselves still “shiny objects”: intermediate and long-duration storage and grid-forming inverters. Until those dependencies become demonstrated, certified and reproducible products, energy planners cannot responsibly rely on solar and wind as the sole pillars of decarbonisation.
The concept, articulated in the source article via the “Iron Law of Technology,” is a necessary reality check for an industry flooded with hype. Every energy technology begins as a promise; only a few survive the transition to reliable, economic practice. Nuclear fusion has been “ten years away” for fifty years — a shining illustration that breakthroughs cannot be scheduled. Fusion may one day solve the underlying problem, but it cannot feature in any credible plan today. The lesson is blunt: policy and investment must favour what works now, not what might work eventually.
What does the Iron Law tell us about today’s energy transition?
Solar and wind have indeed achieved stunning cost reductions and deployment at scale. They are no longer laboratory curiosities. Yet they are still dependent on supporting technologies that are not yet commercially viable at the required scale. The “shiny object” trap is to celebrate generation without solving integration. The current policy environment in many jurisdictions assumes that long-duration storage and grid-forming inverters will appear on schedule — but the Iron Law warns that this is a bet, not a plan. Capital allocated to unproven enablers risks becoming stranded if those technologies fail to materialise or prove uneconomic.
Consider the key dependencies that remain unresolved:
- Long-duration storage (e.g., 10–100 hours) — no dominant technology has yet reached commercial bankability.
- Grid-forming inverters — essential for maintaining stability when renewable penetration exceeds a certain threshold; still in early deployment.
- Intermediate storage (e.g., 4–8 hours) — lithium-ion batteries currently serve this role, but at high system cost for deep decarbonisation.
Until these components are proven products available at scale, the promise of 100% renewable grids remains exactly that — a promise.
Which next-generation technologies are still promises?
The article highlights two prominent “next shiny objects”: Dispatchable Emission-Free Resources (DEFRs) and green hydrogen. DEFRs, most likely in the form of Small Modular Reactors (SMRs), lack any detailed engineering description and are far from commercial readiness. Multiple designs are under development, but no single approach has yet demonstrated technical and economic viability. Including SMRs in national energy plans is premature, even if those plans ultimately depend on them for dispatchable zero-carbon power.
Green hydrogen faces a similar gap. Produced via electrolysis powered by renewables, it is touted as a solution for hard-to-abate sectors such as steelmaking and heavy shipping. But electrolysis is energy-intensive, costly, and largely reliant on the same intermittent renewables whose limitations it is meant to overcome