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A fuel cell is an exothermic device that wastes ca. 50% of the input chemical energy while methanol steam-reforming (MSR) reaction is endothermic. The integration of a low temperature methanol steam-reforming cell (MSR-C) with a high temperature polymer electrolyte membrane fuel cell (HT-PEMFC) in a combined stack arrangement allows the thermal integration of both reactors. A novel bipolar plate of poly(p-phenylene sulfide) (PPS) featuring the fuel cell flow field in one side and the reformer flow field in the other was designed, built and assessed. For the first time are reported high current densities (>0.5 A cm-2) with the integrated system running at 453 K. The system was also ran for more than 100 h at 453 K, at 0.3 A cm-2, with a methanol conversion of>90%. It was observed some degradation of the membrane electrode assembly (MEA) due to the continuous presence of methanol in the reformate stream. Electrochemical impedance spectroscopy (EIS) analyses revealed an overall increase of the resistances. The self-thermal sustainability of the combined device was only reached for >0.75 A cm-2 due to the poor thermal insulation of the combined reactor.

Abstract Concentrated solar power (CSP) plants generate an almost continuous flow of fully dispatchable “renewable” electricity and can replace the present fossil fuel power plants for base load electricity generation. Nevertheless, actual CSP plants have moderate electricity costs, in most cases quite low capacity factors and transient problems due to high inertia. Hybridization can help solve these problems and, if done with the integration of forest waste biomass, the “renewable” goal can be maintained, with positive impact on forest fire reduction. Local conditions, resources and feed in tariffs have great impact on the economical and technical evaluation of hybrid solutions; one of the premium European locations for this type of power plants is the Portuguese Algarve region. Due to the concept innovation level, conservative approaches were considered to be the best solutions. In this perspective, for a lower capital investment 4 MWe power plant scale, the best technical/economical solution is the hybrid CRS/biomass power plant HVIB3S4s with CS3 control strategy. It results in a levelized electricity cost (LEC) of 0.146 €/kWh, with higher efficiency and capacity factor than a conventional 4 MWe CRS. A larger 10 MWe hybrid power plant HVIB3S10s could generate electricity with positive economical indicators (LEC of 0.108 €/kWh and IRR of 11.0%), with twice the annual efficiency (feedstock to electricity) and lower costs than a conventional 4 MWe CRS. It would also lead to a 17% reduction in biomass consumption (approximately 12,000 tons less per year) when compared with a typical 10 MWe biomass power plant – FRB10; this would be significant in the case of continuous biomass price increase.