Tanuj Deora works in the energy industry — specifically to decarbonize energy systems. That’s the technical term for efforts to reduce the reliance on fossil fuels. It’s a vast and complex problem, but Deora and his family try to do their part. At their home in Northwest Washington, they have solar panels, LED lightbulbs and a hybrid minivan. In the kitchen, though, the issue of fossil fuel usage was more personal. Their natural gas cooktop was making Deora sick.