- Geology & Geological
- Institute for Energy Studies
- Prospective Students
- Current Students
The renewable hydrogen production test facility at the University of North Dakota (UND) consists of a 6 kW PEM electrolyzer system with specially designed control system and two 1.2 kW PEM fuel cells. The system is designed for PEM electrolysis hydrogen production allowing advanced control and monitoring over operating temperature, hydrogen system pressure, water resistivity, water flow, stack current and safety. Along with the temperature, pressure and current-voltage sensors, the main components of the system are a 6 kW PEM electrolyzer stack, hydrogen-water phase separator, two 6 kW Xantrex DC power supplies which are capable to deliver up to 200 A to the electrolyzer, a temperature controlled water loop, a two-tube desiccant drying system and a back pressure regulator to control the operating pressure. Water quality is maintained above defined 1MΩ-cm using mixed bed resins and carbon filters. A temperature control unit (chiller) controls the inlet DI water temperature thereby providing control of the operating temperature of electrolyzer. This system is designed to allow higher temperature testing by maintaining DI water temperature with the chiller and a heater provided in oxygen-water phase separator. The picture shown below is UND renewable hydrogen and fuel cell lab. Renewable generated DC power is simulated using power electronics packages. A 5.2 kW programmable DC load bank is used for fuel cell studies. A Solartron frequency response analyzer, 1250A with frequency range from 10µHz to 65kHz is used for electrochemical impedance spectroscopy (EIS) studies of both fuel cell and electrolyzer at the cell and stack level.
Current Development Work
The developmental work currently being performed at UND in this area is carried out primarily by the Departments of Chemical and Electrical Engineering, with support from the Chemistry Department. This is an advantage of a smaller university like UND – collaboration across departments is natural. Although we involve students at all levels, we currently rely on PhD students to perform the bulk of our research. This gives us the capability to explore research questions in great depth. We are application oriented. The experimental component of our program provides the data and capability to verify the models that we are developing. In addition, we view applications from the system level, rather than the component level. Having a strong modelling and experimental component, coupled with an eye toward overall system level efficiency has helped us keep our research meaningful.
Current Modeling Work
Current modeling work is focused on incorporating fuel cell, hydrogen storage, and power electronics models into RPM-Sim and simulating full system (wind turbine, electrolyzer, fuel cell, hydrogen conditioning and storage, power electronics and control, and load) testing under various operating conditions. Electrochemical impedance spectroscopy (EIS) work is focused on testing of a 6 kW PEM electrolyzer and PEM hydrogen compressor for detailed characterization of performance and the development of electrical equivalent circuits to enable study of the impacts of PEM fuel cell and PEM electrolyzers on power system performance. A method of drying hydrogen product gas to a specified dew point is being developed using Peltier effect based thermoelectric coolers (TEC) along with fuzzy logic control. A single, shared power electronics and control system interfacing a wind turbine(s) to PEM electrolyzers is being developed. Efforts to evaluate the feasibility and study the electrochemical compression of product hydrogen gas using PEM cell with high efficiency are planned. Back diffusion of hydrogen, water management, membrane electrode assembly for higher pressure difference will be studied.