Humidifier

A humidifier for increasing a humidity of a supply of air, the humidifier comprising:

• an enclosed gas flow path for the supply of air;
• a heating element including a porous structure of electrically resistive and thermally conductive material configured to substantially vaporise liquid that is passed through the porous structure, the porous structure having a liquid inlet and a vapour outlet;
• and
• an outer housing surrounding at least a portion of the porous structure for containing the liquid and vapour within the porous structure, an enclosure of the enclosed gas flow path surrounding the outer housing so that the enclosed gas flow path is between the outer housing and the enclosure of the enclosed gas flow path and the heating element and the outer housing are immersed within the supply of air in the enclosed gas flow path;
• wherein the porous structure includes a first electrical connector and a second electrical connector, the first electrical connector and the second electrical connector being configured for receiving electrical power and applying a voltage across the porous structure so that the porous structure generates heat;
• and
• the vapour outlet is arranged to expel heated vapour for delivery into the enclosed gas flow path to increase the humidity of the supply of air.