A dirty secret of mobile communications is that it uses lots of electricity. It’s also sometimes powered by giant tanks of diesel fuel, especially in poor countries. But new research shows that it’s possible to build complex networks that run on renewable or other local power sources, with no need for backup from the electricity grid or diesel fuel.
Small transmitters, called small cells, will provide much of the capacity for future networks. These small cells might be tethered to small windmills or solar panels and batteries, or even include their own built-in power sources and batteries, as in this prototype. But fluctuations in the electricity generated at each cell could make the networks they serve less reliable.