A Life Cycle Assessment of the PureCell Stationary Fuel Cell System ...

Executive Summary
The PureCell Model 200 Power Solution (formerly the PC25) is a stationary power
system manufactured by UTC Power. It uses a 200 kW phosphoric acid fuel cell with a
lifetime of 85,000 hours and it has an internal natural gas steam reforming system. The
PureCell system can operate in both grid-connected and grid-independent mode and it
also provides the option of heat recovery. When it functions as a combined heat and
power (CHP) system, efficiency of 80% is achieved. Since 1991, more than 275
PureCell power systems have been installed at various locations around the world.
UTC Power is currently redesigning the system and would value having a life cycle
assessment (LCA) to highlight opportunities for improvement of its environmental
performance. LCA can clarify which stages in the product life cycle and which elements
of the product cause the most environmental pressure. Product development and
improvement is therefore one of its direct applications.
The LCA results show that the use phase has by far the biggest environmental impact.
The input of natural gas in the steam reforming process and the CO 2 emissions caused by
this process are the main contributors to the use phase impact. Maximizing the hydrogen
output of the steam reforming process and increasing the efficiency of the
electrochemical reaction in the fuel cell stack are therefore the main opportunities to
improve the environmental performance of the PureCell system. LCA results for a
separate analysis of the manufacturing phase show that the fuel cell stack is responsible
for almost half of the environmental impact of the manufacturing phase. The main cause
is the high amount of energy used in the fuel cell stack manufacturing process. The
biggest impacts per material in the manufacturing phase are caused by platinum used in
the fuel cell stack, copper used in the power conditioning and control devices, and
stainless steel 304 used for manifold applications. In the case of platinum especially it is
beneficial to pursue a high recycling rate, since the environmental impact of recycled
platinum is much smaller than that of raw platinum. The end-of-life phase has a small
environmental impact compared to the use and manufacturing phases.
This report also includes an analysis of two scenarios as opportunities for environmental
improvement of the PureCell system. One scenario analyzes the effect of using
renewable hydrogen from wind energy instead of using hydrogen from natural gas steam
reforming. The environmental impact is highly dependent on hydrogen transport from
the wind turbine site to the PureCell system site. However, if a transport distance of
100 miles is assumed, a decrease in the total PureCell system life cycle environmental
impact by a factor 7 is reached. The second scenario analyzes an alternative end-of-life
treatment including reuse of PureCell system components and maximizing platinum
recycling. Component reuse impacts both the end-of-life phase (less output to waste
management) and the manufacturing phase (less input of materials and energy) and
shows a 16% decrease in the aggregated environmental impact of the manufacturing and
end-of-life phase. The use phase impact is not taken into account here because the
alternative end-of-life scenario aims only at reducing the environmental impact of the
manufacturing and end-of-life phase.