Balance-of-Plant (BOP) cost for PEM fuel cell systems are now equal to or exceeding the cost of PEM fuel cell stack. The fuel cell systems cost analyses funded by the Fuel Cell Technologies Office (FCTO) of the U.S. Department of Energy (DOE) confirms the near equivalency of the BOP cost to fuel cell stack cost for PEM fuel cells in the studies by Battelle[1], Lawrence Berkeley National Laboratory[2], and Strategic Analysis Inc.[3]. The cost equivalency between the BOP and the PEM fuel cell stack is observed over the full spectrum of fuel cell applications; Material Handling Equipment (MHE) fuel cell systems, stationary fuel cell systems, automotive fuel cell systems. James et al[4]evaluated PEM automotive fuel cell costs and found that at production rates of 30,000 automotive units per year or greater the BOP cost were more than the PEM fuel cell stack cost, as shown in Figure 1.Battelle[5] reports the BOP cost is 3.5X the cost of the fuel cell stack in their analysis of the cost of a PEM 10 kW fuel cells for MHE; these data are represented in Figure 2 where the balance of plant is 59% of the fuel cell system cost at production rates of 10,000 MHE fuel cell systems per year.For a PEM 100 kW hydrogen fueled stationary fuel cell systems, Wei and McKone[6]of Lawrence Berkeley National Laboratory (LBNL) reported the ratio of BOP-to-stack cost is 1.3 at production rates of 1,000 hydrogen fueled units per year. For a PEM 100 kW reformate fueled stationary power plants, the LBNL data demonstrate the ratio of BOP to fuel cell stack cost is 1.1 for a production rate of 10,000 fuel cell systems per year.LBNL evaluated smaller hydrogen fueled PEM stationary, backup power (BUP) systems and the ratio of BOP to fuel cell stack cost was 1.5 for a 10 kW system. At BUP system production levels of 50,000, the ratio of BOP-to-fuel cell stack cost increased to 2.3 in the LBNL data.A three part approach to improving BOP performance, durability and reduced cost is:Increasing awareness of BOP specifications for performance, durability and cost within the supply chain.Optimization of manufacturing processes to reduce cost of BOP componentsDevelopment of fuel cell system BOP components that meet original equipment manufacturers specifications. Increasing awareness of BOP specifications: For many years, the approach to fuel cell BOP components has been to use Off The Shelf (OTS) components developed for non-fuel cell applications. Overall, this approach has not been successful because of a lack of awareness of the OEM specifications by the BOP manufacturers. The Ohio Fuel Cell Coalition brought the OEMs and BOP manufacturers together to share specifications, discuss manufacturing capabilities, and establish acceptable cost targets. The results of these exchanges will be presented.Optimization of Manufacturing Processes for BOP Components: The FCTO has sponsored manufacturing R&D programs for the last three years. Manufacturing R&D for BOP components will be discussed and recommendations for optimization of manufacturing methods for specific BOP components presented.Development of Fuel Cell Balance-of-Plant Components: Replacement of OTS components that are mismatch for fuel cell applications will in many cases require alternative materials and specialized designs to meet the OEM durability and performance requirements. The R&D pathways to identify alternative materials and specialized designs will be discussed.