A combustion device includes a combustion chamber with an outer wall enclosing a combustion space that can contain a fuel source on an adjustable fuel rack, side walls, a lower air jet tube and at least one air upper jet tube, a top opening, a grill top assembly to cover the opening, and a detachable power module. The power module can have batteries and a blower. The blower can force ambient air into a manifold, through the jet tubes, through ports in the jet tubes, and into the combustion chamber.