Researchers at MIT have come up with an alternative system for generating electricity, which harnesses heat and uses no metals or toxic materials.
A wire made from tiny cylinders of carbon known as carbon nanotubes can produce an electrical current when it is progressively heated from one end to the other, for example by coating it with a combustible material and then lighting one end to let it burn like a fuse.
The researchers caution, however, that it could take several years to develop the concept into a commercial product.
