A coil-in-coil electric heating assembly for industrial applications heats any gas through an annular space between the coils to very high temperatures. Gas is introduced into the annular space through one open end of a tubular enclosure and leaves through an opposite end after being significantly heated. Coils may be made from several heating element materials and may be wound in the same direction or opposite direction. The opposite winding direction often gives a higher temperature of the exit gas. Temperatures even as high as 1500° C. in the exit gas have been recorded. The heating system may be utilized to generate superheated steam for industrial applications even in a recirculating manner.