The need for reliable renewable energy is growing fast, as countries around the world—including Switzerland—step up their efforts to fight climate change, find alternatives to fossil fuels and reach the energy-transition targets set by their governments. But renewable energy can’t be incorporated into power grids efficiently until there is a way to store it on a large scale. “Most forms of renewable energy are dependent on weather conditions, which results in large fluctuations in the power they supply,” says Danick Reynard, a Ph.D. student at EPFL’s Laboratory of Physical and Analytical Electrochemistry (LEPA). “But power grids aren’t designed to manage these kinds of fluctuations.” Hydrogen, because it can supply energy consistently regardless of the weather, is now attracting growing attention.