A power generator (400, 500, 600, 700) comprising: a housing (200, 603); a chemical hydride fuel block arranged within the housing and adapted to produce hydrogen when exposed to water vapor; and an air conduit (110, 705, 710), disposed about the chemical hydride fuel block in the housing (200, 603), the air conduit (110, 705, 710) comprising a fuel cell portion (112, 730, 805), and a water vapor permeable, hydrogen impermeable membrane portion (114, 740, 810) adapted to allow water vapor to pass through to cause release of hydrogen from the fuel block; the chemical hydride fuel block being adapted to be removable from the housing (200, 603) and the air conduit (110, 705, 710); the housing (200, 603) including an air intake opening (215, 515, 622) adapted to draw air containing oxygen and water vapor into the housing (200, 603) and into the air conduit (110, 705, 710); the air conduit (110, 705, 710) being adapted to flow the air from the air intake opening (215, 515, 622) past the fuel cell portion (112, 730, 805) to provide oxygen to the fuel cell portion (112, 730, 805) and to receive water vapor from the fuel cell portion (112, 730, 805), and to flow the air including the received water vapor generated by the fuel cell portion past the permeable membrane portion (114, 740, 810) to transport water vapor across the membrane portion (114, 740, 810) to the replaceable chemical hydride fuel block; and the chemical hydride fuel block further comprising an exhaust opening corresponding to the air conduit (110, 705, 710) to facilitate exhausting air and heat from the air conduit (110, 705, 710) out of the housing (200, 603). a housing (200, 603); a chemical hydride fuel block arranged within the housing and adapted to produce hydrogen when exposed to water vapor; and an air conduit (110, 705, 710), disposed about the chemical hydride fuel block in the housing (200, 603), the air conduit (110, 705, 710) comprising a fuel cell portion (112, 730, 805), and a water vapor permeable, hydrogen impermeable membrane portion (114, 740, 810) adapted to allow water vapor to pass through to cause release of hydrogen from the fuel block; the chemical hydride fuel block being adapted to be removable from the housing (200, 603) and the air conduit (110, 705, 710); the housing (200, 603) including an air intake opening (215, 515, 622) adapted to draw air containing oxygen and water vapor into the housing (200, 603) and into the air conduit (110, 705, 710); the air conduit (110, 705, 710) being adapted to flow the air from the air intake opening (215, 515, 622) past the fuel cell portion (112, 730, 805) to provide oxygen to the fuel cell portion (112, 730, 805) and to receive water vapor from the fuel cell portion (112, 730, 805), and to flow the air including the received water vapor generated by the fuel cell portion past the permeable membrane portion (114, 740, 810) to transport water vapor across the membrane portion (114, 740, 810) to the replaceable chemical hydride fuel block; and the chemical hydride fuel block further comprising an exhaust opening corresponding to the air conduit (110, 705, 710) to facilitate exhausting air and heat from the air conduit (110, 705, 710) out of the housing (200, 603).