have to be considered when studying the
quality of fuel cell generated waters.
After a nationwide search, the research
team identified six laboratory-scale PEM
fuel cells operated at research centers
throughout the United States. They
collected two water samples (exhaust [or
product] water and inlet humidification
water) from each bench top fuel cell and
analyzed them for a suite of contaminants.
The overall results indicate that water
generated from these fuel cells is relatively
pure. Contaminant levels are lower than
USEPA Maximum Contaminant Levels
(MCL) or water quality levels provided by
municipal water supplies representative
of some U.S. cities.
There were two exceptions where the
fuel cell waters were characterized by
lead and antimony concentrations,
respectively, that were higher than their
MCLs. Analysis of inlet humidification
water indicated that its quality can
adversely impact the overall water quality.
A second round of sampling was considered
but declined so that the research team
could focus on a laboratory-scale PEM
fuel cell set up at ASU, and a commercial-scale PEM fuel cell located at a local energy
provider. The lab-scale setup allows the
team to carefully study a range of operating
scenarios under controlled experimental
conditions. The commercial scale fuel cell
will help the research team anticipate the
quantity and quality of water generated
under realistic environmental conditions.
Preliminary results of the lab fuel cell
with a self-humidifying proton exchange
membrane show the water generated
consistently exhibits a very high quality.
It may not require additional treatment.
Concentrations of all ions were below
their enforceable MCL. However the
fluoride observed at a specific range
of current densities suggests membrane
decomposition. A new membrane that is
thicker and has a slightly different chemical
composition is currently being studied.
The commercial scale fuel cell was operated
for several months and the data are still
Research will be complete later this year
and a published report is anticipated in
early 2010. The report will include the
literature review, results of the sampling
events of fuel cells operated across the
United States, performance information
of the bench top fuel cell at ASU and the
commercial scale fuel cell, an evaluation
of water treatment needs for fuel cell
generated water, and a technology
comparison for producing high quality
water. For more information about the
study, contact Jennifer Warner at