Alan Bernstein and colleagues recommend a global grand-challenge strategy for prioritizing clean-energy research (Nature 538, 30; 2016). In my view, this 'cockpit' approach — relying on top-down steering to seek out global solutions — risks galvanizing research along a fixed path.

A diverse set of research initiatives implemented across different scales could be a better approach. That would deliver ways of using energy sustainably under different social and cultural circumstances. The long-term questions for energy research are as much about the evolution of energy use as the revolution in its production.