A method of producing hydrogen gas using a hydrogen generator, the hydrogen generator comprising a container; a first reactant storage area within the container, the first reactant storage area having a volume and containing a fluid comprising a first reactant; a reaction area within the container, the reaction area having a volume; an effluent storage area within the container, the effluent storage area having a volume; a fluid passage from the first reactant storage area to the reaction area; an effluent passage from the reaction area to the effluent storage area; a compressed filter contained within the effluent storage area; a liquid impermeable, gas permeable component; and a hydrogen outlet; the method comprising the steps: moving the first reactant from the first reactant storage area, through the fluid passage, to the reaction area; reacting the first reactant in the reaction area to produce hydrogen gas and an effluent; moving the hydrogen gas and the effluent from the reaction area, through the effluent passage, to the effluent storage area; and passing the hydrogen gas through the filter and the liquid impermeable, gas permeable component to the outlet; wherein: the first reactant storage area volume, the reaction area volume or both the first reactant storage area and the reaction area volumes decrease, the filter expands, and the effluent storage area volume increases as the first reactant is moved from the first reactant storage area and the hydrogen gas and the effluent are moved from the reaction area to the effluent storage area; a moveable partition separates the effluent storage area from at least one of the first reactant storage area and the reaction area; a portion of the filter is attached to the moveable partition; and all hydrogen gas passing to the outlet passes through the effluent storage area. moving the first reactant from the first reactant storage area, through the fluid passage, to the reaction area; reacting the first reactant in the reaction area to produce hydrogen gas and an effluent; moving the hydrogen gas and the effluent from the reaction area, through the effluent passage, to the effluent storage area; and passing the hydrogen gas through the filter and the liquid impermeable, gas permeable component to the outlet; wherein: the first reactant storage area volume, the reaction area volume or both the first reactant storage area and the reaction area volumes decrease, the filter expands, and the effluent storage area volume increases as the first reactant is moved from the first reactant storage area and the hydrogen gas and the effluent are moved from the reaction area to the effluent storage area; a moveable partition separates the effluent storage area from at least one of the first reactant storage area and the reaction area; a portion of the filter is attached to the moveable partition; and all hydrogen gas passing to the outlet passes through the effluent storage area. the first reactant storage area volume, the reaction area volume or both the first reactant storage area and the reaction area volumes decrease, the filter expands, and the effluent storage area volume increases as the first reactant is moved from the first reactant storage area and the hydrogen gas and the effluent are moved from the reaction area to the effluent storage area; a moveable partition separates the effluent storage area from at least one of the first reactant storage area and the reaction area; a portion of the filter is attached to the moveable partition; and all hydrogen gas passing to the outlet passes through the effluent storage area.