The speed and size of computer chips are limited by how much heat they dissipate. Resistive heating in electronics generally outweighs smaller thermoelectric effects that can locally cool a device. To help dissipate heat, additional cooling with fans is commonly employed.

William King and colleagues, University of Illinois, Urbana-Champaign, USA, have used an atomic force microscope tip as a temperature probe to make the first nanometer-scale temperature measurements of a working graphene transistor. The measurements revealed that thermoelectric cooling effects can be stronger at graphene contacts than resistive heating. This allows the devices to cool themselves.
This self-cooling effect would eliminate the need for additional cooling, making graphene-based electronics more energy efficient than their current silicon counterparts.

• Nanoscale Joule heating, Peltier cooling and current crowding at graphene–metal contacts
  K. L. Grosse, M.-H. Bae, F. Lian, E. Pop, W. P. King,
  Nature Nanotechnol. 2011.
  DOI: 10.1038/nnano.2011.39