Given the continual improvement in gas appliance efficiencies, it is surprising that commonly available tea kettles have efficiencies as low as 40% when used on a gas range. This innovative “center flue” kettle is specifically designed for gas cook tops and is based upon the design principles used in modern gas water heaters, which now reach energy efficiencies over 90%.
The center flue portion of the kettle improves heat transfer in three ways. First, it is made of a highly conductive and formable material such as copper with a flat portion that is in direct contact with the gas flame. Second, it is formed with a ribbed or fluted surface to increase surface contact between the heated air, the metal surface and the water. Finally, the flue directs more of the heat of the gas flames through the kettle’s interior when it would otherwise spill around the outside.
Traditional kettles must locate their handles across their top, away from the heat escaping around the sides. In the center flue design, the handle can be located on the side which is a more ergonomic position for pouring. Furthermore, the handle can be integrated with a high temperature plastic cover that insulates against heat loss after the water is heated.
As can be seen in the attached images, such a kettle could be made of parts that are inexpensive to form and easily assembled. Consequently, a purchaser of a center flue kettle would heat water faster, use less energy and find it more comfortable to use than currently available kettles. While most recent kettle designs attempt to differentiate themselves through aesthetic elements, this kettle is distinguished by a design that is derived naturally through form following function.