Technology converts industrial waste heat into electricity

The high-efficiency thermal waste heat energy converter actively cools electronic devices, photovoltaic cells, computers and large waste heat-producing systems while generating electricity, according to Scott Hunter, who led the development team at the US Department of Energy’s Oak Ridge National Laboratory (ORNL).

‘In the US, more than 50 per cent of the energy generated annually from all sources is lost as waste heat, so this actually presents us with a great opportunity to save industry money through increased process efficiencies and reduced fuel costs while reducing greenhouse-gas emissions,’ said Hunter.

Hunter’s technology is said to use cantilever structures that are about 1mm² in size. It is claimed that about 1,000 of these energy converters can be attached to a 1in square surface such as a computer chip, concentrated photovoltaic cell or other devices that generate heat.

Although the amount of electricity each device can generate is small — one to 10 milliwatts per device — many arrays of these devices can be used to generate sizable amounts of electricity that can power remote sensor systems or assist in the active cooling of the heat-generating device, reducing cooling demands.