This paper reviews the current techniques being applied and that have been patented in relations to the cooling of insulated electrical cables. Patents in three specific areas of application are described. The first set of patents relates to cooling methods applying water and cryogenic coolant technology. These fluid-based cooling systems have been applied to underground transmission lines, superconductors and welding cables. The second area relates to the application of redox reactive material to the cooling of electrical cables. By utilising the endothermic/exothermic characteristics of the oxidation-reduction reaction, the temperature of the cable can be controlled. The third application area is the use of phase change materials (PCM) as a heat dissipation medium utilising their high latent heat of melting. Finally, the current and future developments in the field are briefly discussed.