THE odd thing about nanotechnology conferences is that they often feature innovations that are anything but nanoscale. You could be forgiven for thinking that as long as it’s smallish, it’s nanotech.
One invention to be revealed at this week’s conference is a case in point. A team based in Washington has developed a 3-millimetre-wide “micro heat engine” that converts heat into electricity. Its inventors hope arrays of them will one day use waste heat to replace batteries in many consumer appliances.
So far, attempts to build tiny electricity generators have focused on miniaturising hydrocarbon-powered internal combustion engines to turn a…
