A thermal cracking apparatus and method includes a body having an inner volume with a longitudinal axis, where a reaction zone surrounds the longitudinal axis. A feedstock process gas is flowed into the inner volume and longitudinally through the reaction zone during thermal cracking operations. A power control system controls electrical power to an elongated heating element, which is disposed within the inner volume. During thermal cracking operations, the elongated heating element is heated to a molecular cracking temperature to generate the reaction zone, the feedstock process gas is heated from the elongated heating element, the power control system uses a feedback parameter for adjusting the electrical power to maintain the molecular cracking temperature at a substantially constant value, and the heat thermally cracks molecules of the feedstock process gas that are within the reaction zone into constituent components of the molecules.