Hydrogen is the energy future | Letters

Renewably generated hydrogen could supply energy storage at scales many times beyond which even the largest battery systems could attain, writes Mike Koefman; while John Ellis says it’s time for joined-up thinking on our future energy strategyThere is truth in Professor Underwood’s assertion (Letters, 16 May) that nothing can surpass the “round trip” efficiency of lithium-ion batteries from, for example, solar input to final user’s output. But in focusing on this un