River power - time for some sums

Just back from Budapest, where the Danube transects the city in a stately curve. It seems to run at a reasonable walking pace (this in June - faster in March/April, I'll bet), and must contain a fair slug of energy available for capture. Of course, this is exactly what Verdant are doing in New York at the moment.

The difference here is that Budapest has lots of lovely bridges, which could potentially act as foundations for tidal turbines (as Southampton University demonstrated at a small scale on Yarmouth Pier).

What the world needs now is some calculations on the possible power available from the Danube in Budapest. And once you've covered the Danube, there's the Rhine, the Rhone, the Volga, the Thames....