Results from the Open Hydrogen Fueling Methodology Workshop
by Jesse Schneider

A cross-industry group of fuel providers, automakers (OEMs), and other organizations wrote a technical paper "Optimizing Hydrogen Vehicle Fueling", which will be released in the NHA 2005 conference proceedings. The purpose of the paper was to show the origins of hydrogen vehicle fueling in various demonstration projects up to the current "state of the art" being developed by organizations such as the SAE fuel cell vehicle committee.

Many companies were involved in this effort. For instance, DaimlerChrysler began with a hydrogen vehicle demonstration project in 1984. Frank Lynch, of Hydrogen Components, Inc. was one of the pioneers in this area who brought many of the ideas we utilize today such as: H2 fueling station-vehicle communications, temperature compensation fueling control on the dispenser side, cooled hydrogen fueling (conceptualized originally by Dick Cromwell), and density targeted fueling. These are the components which can be seen, optimized, in many demonstration projects across the country and the world. Many automakers and fuel providers have also contributed to these efforts.

Unfortunately, not all of these concepts are widely used. Mr. Lynch and Jesse Schneider, from DaimlerChrysler, hosted a workshop on how to get hydrogen vehicle demonstration projects lessons learned and concepts for 'optimizing hydrogen fueling' communicated to the industry. The Open Hydrogen Vehicle Fueling Workshop was developed for the industry to agree upon a minimum performance targets to insure industry-wide station-vehicle interoperability. At this point, it is still too early to make standards relating to fueling, however it would be beneficial for industry guidelines to set minimum performance criteria to insure that performance targets are met and that storage parameters are not exceeded.

At the same time, industry is dealing with intellectual property concern in the form of patents. Some standard development organizations industry groups such as SAE, CSA and others are currently stalled in developing guidelines due to these issues. One goal of this Open Fueling Methodology paper was to search for a way to move forward. In many occasions it was found that there are publicly available concepts such as density targeted fueling (published in a paper from Air Products and Frank Lynch in 1997). However, pre-cooled fueling, which involves literally cooling the hydrogen before it is dispensed, is believed to be essential for fueling with 70 MPa (10,000 psi). There are however, numerous patents in this regard.

One of the co-authors of the paper, Gas Technology Institute's Bill Liss announced at the workshop that GTI is intending to donate their "cooled gas" patent for the SAE J2601 draft technical report. This should be applauded by the industry as a step forward. There were a number of concepts (not previously documented) which were revealed in the workshop, such as having the station control the fueling process. This concept and others were later incorporated in the paper.

The authors of the paper are planning to give this NHA 2005 technical paper to SAE, CSA America and CaFCP teams in the hopes the industry can benefit and develop an open hydrogen fueling guideline.