Small 12-W System

Hydrogen is supplied up a central tube to the undersides of all the MEAs 

The hydrogen supply is dead-ended , there is no circulation or venting - though there may be a system of periodic manual purging to release impurities from time to time. 

This then is an attempt to produce a pure fuel cell system, with the absolute minimum of extra devices. The efficiency, as with all fuel cells, varies with current, but at rated power it is liable to be around 48% (refer lower heating value (LHV)), that is, the voltage of each cell will be about 0.6 V. 

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