The sub-zero start-up capability remains as a technical barrier for large-scale adoption of proton exchange membrane fuel cell (PEMFC) vehicles; the situation is even worse when carbon-based (i.e. graphite) bipolar plates, with a larger heat capacity, are used. Herein, we develop an alternate hydrogen pump (AHP) method, which enables successful start-up of a graphite-bipolar-plate (GBP) PEMFC from -30 degrees C. By applying an alternate voltage to both sides of the PEMFC under H-2 atmosphere, the AHP method warms up the PEMFC using heat generated mainly from ohmic polarization and eliminates the hazard of super-cooled water freezing. Additionally, The AHP method causes minor changes of the PEMFC system. The energy efficiencies of the AHP method are analyzed and further improvements are proposed. (C) 2019 The Electrochemical Society.