A research study by the National Center for Sustainable Transportation examined the feasibility of deploying renewable hydrogen and DC fast-charging stations for fuel cell electric vehicles (FECV) and plug-in electric vehicles (PEV) in California, and in integrating such stations with the electricity grid to lower infrastructure cost and encourage the use of renewable energy.
A key challenge with such a design is that it represents a higher initial capital cost, and its capacity will not be fully utilized in the early stages of the PEV and FCEV market. However, the proposed system would take advantage of underutilization by serving as flexible energy storage for the grid, benefiting both utility operators and fueling/charging station owners.
Researchers designed two station configurations that integrated hydrogen fueling/DC fast charging: one used battery energy storage, and the other used hydrogen energy storage. They compared these designs with the currently-in-use distributed station layout, in which hydrogen fueling and DC fast charging are separately sited. Between the two integrated designs, the battery storage was found to be more energy efficient, while the hydrogen storage was more economically efficient. The distributed station had overall lower capital and maintenance costs, but was the most reliant on grid energy.
- Compared to distributed stations, integrated stations are more energy efficient and economically attractive in terms of hydrogen fuel cost: Based on the schedule used to determine future electricity cost, integrated stations found hydrogen cost savings of upwards of 30 percent.
- The cost of PEV charging at the integrated stations was projected to be close to that of the currently-in-use distributed stations.