How did you cook your breakfast this morning? If you’re one of the roughly 3 billion people worldwide who live in energy poverty, it was over an open fire or a pile of lit charcoal inside a rudimentary stove. Cooking this way is inefficient, wasting up to 90% of the heat from combustion. It is also dangerous, affecting vision, causing heart and lung disease and ultimately shortened lives. Almost half the world’s population still cooks this way because they need to eat and don’t have other options, but thankfully progress is being made.