Power from water wheels for 100 million people?

The German magazine Der Spiegel has a article on new water wheel technology from Wasserrad Drews. Water wheels used to produce mechanical energy for ages before burning fossil fuel took over in the 19th century. New technology may bring back water wheels, in small installation next to a river, for electricity generation.



The concluding sentence claims an optimistic estimate of providing electricity for 100 million people world-wide. I was more interested in one section that spells out the costs for one installation:

[Mr Unger installed] a metal wheel with a nominal capacity of 11.5 kW [...]. Unger feeds the electricity into the grid and gets 9.67 cents per kWh. [...]. Unger invested roughly 60,000 Euro. Now he makes 10.000 Euro a year.

The numbers seem to add up: 11.5kW * 24 hours/day * 265 days/year * 9.67 c/kWh equals 9742 Euro/year. The capital costs are about 5000 Euro per kW.