Disclosed are methods of making low voltage joule heating elements (10, 40, 50) from carbon nanotubes (CNT) (32). In an embodiment, the heating element (10) includes layers (12) of aligned thin film CNTs. In another embodiment, the heating element (40) includes CNTs (32) dispersed in a polymer (34) to form a CNT polymer composite (30). In another embodiment, the heating element (50) includes CNT thread (52) stitched to a fabric (54). Each embodiment further includes a pair of electrodes (20, 22, 42, 44, 56, 58) that are configured to be couple to a source of electricity. Embodiments further include an encapsulating film (24, 46) over at least the heating element. The heating elements (10, 40, 50) produced by the processes disclosed herein are lightweight and highly efficient and suitable for many uses including incorporation into objects such as clothing and footwear.