Photovoltaic devices that directly convert sunlight to electricity aren’t new. Various types of these energy transformers, which are also known as solar cells, have been around for decades. The type Snaith refers to, perovskite solar cells, has been studied intensely only in the past year and a half. During that time, numerous researchers joined the effort, attracted by these cells’ promise to be inexpensive yet high performing. These scientists quickly boosted perovskite solar cells’ electrical output. Now they are working to broaden the cells’ appeal by tailoring their chemical compositions to further boost electrical output, by improving processing methods and stability, and by figuring out why these solar cells perform so unexpectedly well.