Q: Regarding the 100 cycle test, will this test be in a closed or open system, or does it matter? By open system I mean that during hydrogenation hydrogen is taken fresh from the hydrogen tank, as opposed to being taken from the previous dehydrogenation. A: While we haven't specified the test procedures, for our testing it will qualify as an open system per your definition. We will be analyzing the desorbed gas to verify it is hydrogen and determine any impurities. Q: Are electrochemical methods for hydriding and dehydriding allowed in the contest? A: We have not specified test methods. Electrochemical charging and discharging is an acceptable way for sorption capacities of some materials to be tested. The H-Prize is targeted at materials capable of storing gaseous hydrogen and therefore must be capable of being charged and discharged with gaseous hydrogen. The sorption properties will be determined by our lab using gaseous methods, not electrochemical methods, so the short answer is that the materials need to be capable of being tested by other than just electrochemical methods.