A system includes a flow-through electric generator and an electrolytic cell. The flow-through electric generator includes a turbine wheel, a rotor, and a stator. The turbine wheel is configured to receive natural gas from a natural gas pipeline and rotate in response to expansion of the natural gas flowing into an inlet of the turbine wheel and out of an outlet of the turbine wheel. The rotor is coupled to the turbine wheel and configured to rotate with the turbine wheel. The flow-through electric generator is configured to generate electrical power upon rotation of the rotor within the stator. The electrolytic cell is configured to receive a water stream and the electrical power from the flow-through electric generator. The electrolytic cell is configured to perform electrolysis on the water stream using the received electrical power to produce a hydrogen stream and an oxygen stream.