Andreas Nunzer, the mayor of Spitz by the Danube river, told the press that it was impossible to use the wind turbines or the solar panels, so they needed to look for another way of producing electricity in an eco-friendly way. Eventually, they came up with the idea of using the power of the strong river current.

They created three prototype six-tonne buoys, placed them in the river and figured that the river current turns the turbines below the surface fast enough for each of them to produce enough electricity for 250 people. During the trials, the three turbines were able to produce between 40 and 80 gigawatts of electricity and the mayor just confirmed to AFP that permissions have been obtained to add six more into the river.

The river turbine technology is terribly clever. Not only it is leaving virtually zero ecological footprint and requires no special infrastructure, it is also – at the moment – the only way of securing non-stop renewable energy; every hour, every day of the week without being dependent on strong winds or the sun's energy.

The manufacturer claims the buoys will have no effect on shipping or plant and animal life in the river. They river turbines are acceptably large and simple to use and install, so they represent a very attractive option of securing electricity even in more remote areas, providing that a river runs through it.

The Austrian company that developed the technology, Aqua Libre, is set to begin mass production next year.