Most of us brew the way we cook, which is to say, with gas or electricity. When we’re just starting out with extract kits, we use whatever we have at hand, usually the kitchen stove. Moving up to larger batches or bigger boils often entails a move to an outdoor propane burner, and those who really dive in use sophisticated brew rigs that commonly rely on propane, natural gas, or electricity for heat.
While gas and electricity differ in how they create heat, they’re united in the manner in which they deliver it. Both rely on direct contact with some kind of heat source, a phenomenon scientists call conduction. In the case of gas, a flame heats the kettle (along with the surrounding air), which in turn heats your wort. Electric brewing typically involves direct contact between an electric heating element and water or wort, a combination that necessitates the utmost in safety precautions.
But there’s another way to heat wort that doesn’t get as much attention: induction. Unlike gas and electric methods, which depend on the direct transfer of heat from a source, through the kettle, and to the wort, induction turns the kettle itself into the heat source. There’s no middleman.