G.D. Botto, an Italian inventor and physicist, performing experiments on a technique for hydrogen generation, has discovered that a chain of iron and platinum wires, wrapped around a wooden stick and alternately connected as thermocouples, can be used to convert a temperature difference into an electric voltage. The iron-platinum junctions were evenly positioned on opposite sides of the stick. Heating this thermocouple with a flame of burning alcohol, Botto managed to generate electricity. By this, he dissociated water into hydrogen and oxygen through the well-known electrolysis.
Nowadays, when an inventor isn’t such a big deal after all, but instead the institute that he’s working fpr, Roberto de Luca of the University of Salerno in Italy, aided by a team of scientists, revised G.D. Botto’s experiments and adapted them with the technology and modern requirements. For example, they substituted the copper for platinum in the thermocouples. They also proposed completely replacing Botto’s thermocouples with thermoelectric semiconductors for greater efficiency.
But what’s most interesting about their innovations is the fact that they’re not going to heat the thermocouple on one side with an alcohol lamp, but with the Sun’s power. To cool the other side (in order to create a temperature difference), the wooden stick might be replaced with a hollow electrically insulating material through which water could run to cool the desired junctions. So, here’s an interesting modernized invention that uses the solar power to heat matter and directly generate electricity, other besides the photovoltaic effect.
Indeed, the theoretical calculation provided a small power for this device, about 20mW, as PhysOrg.com says, but it’s enough to slowly, cheaply and surely make hydrogen (read: energy) out of nothing (read: solar power). If we don’t give a dime on it, then it’s free, and it’s also protecting the environment from the polluting means we would otherwise have used.