HOT. The word carries so many meanings: passionate, sizzling, trendy, intense, and yes, sexy. But for us, it signals our favorite month. Meet the 20 movers and shakers that have us fired up this year.

Graduating from college in Nova Scotia at the age of 17, Danielle Fong faced the “what do you want to do when you grow up” question a little earlier than most people—which might account for her idealistic answer.

“I decided I wanted to solve an important problem—and the energy problem was by far the most important that I could see being solved technologically.” Specifically, how to store solar and wind energy, which would make relying on renewable power truly practical.

Her solution? Capturing and releasing it—efficiently—via compressed air. Not surprisingly, such technology would be of great interest to, say, the developers of solar and wind farms, municipalities, big industry, and the armed forces. (Being able to generate reliable power would save not just money but lives.)

What’s more, says the founder and chief scientist of LightSail Energy, the “unintended positive consequences” would make this scientific advance revolutionary. “If you can democratize the production, storage, and usage of energy”—so that average citizens can power their own light, heat, refrigeration, clean water, and Internet connections—“you can totally transform how people live. I mean, that’s incredible.”

What Danielle Fong does with her rare free time

“I play music—I really like to play the keyboard and the guitar, and I used to compose a lot. I am making a little more time for that. I’ve been teaching myself to draw—I’m doing pretty good faces now. I love going for a walk around Lake Merritt. I like long walks—they basically keep me sane. I spend a lot of time helping people out with their own projects, their own ideas, the things they want to do. It is essentially my social life. The way to spend any time with me as a friend is to do some project that I think needs to happen, so maybe 50 hours a week is working with my friends and LightSail, and the other 40 hours a week I’m working with other friends on their projects. It means that my social life tends to be only with other people starting up cool new projects, but… these are my people. I love them.”