00:44 - 01:06 the showing of a Kaplan turbine during or in between the Pelton and Francis turbines is quite confusing here. There are better imagery of Pelton turbines with multiple jets, complex shapes of the chambers around the Pelton turbine to not let the water hit the wheel again and slow it down, the precise geometry of the buckets with split in the middle, or the nozzle with spike valve and the quick-action emergency valves that can be shown here to underline the expensive equipment needed for Pelton turbines. 02:23 - 3:21 The last graph shows also the cross-flow turbine, which is not explained. Better to either hide it or also comment on it. General comment: the narrator mentions for almost all types that they are complex and expensive, but there are also simpler turbine technologies, such as the Archimedes screw and water wheels. The drawback is: they have lower efficiency. These technologies can be useful when the potential yield is not so large, like limited flow and/or low head (e.g. micro-hydro, local or private supply). Then a cheaper, simpler solution can be beneficial, as a larger investment in a more sophisticated technology will not pay itself back (low or no return on investment).
00:44 - 01:06 the showing of a Kaplan turbine during or in between the Pelton and Francis turbines is quite confusing here. There are better imagery of Pelton turbines with multiple jets, complex shapes of the chambers around the Pelton turbine to not let the water hit the wheel again and slow it down, the precise geometry of the buckets with split in the middle, or the nozzle with spike valve and the quick-action emergency valves that can be shown here to underline the expensive equipment needed for Pelton turbines.
02:23 - 3:21 The last graph shows also the cross-flow turbine, which is not explained. Better to either hide it or also comment on it.
General comment: the narrator mentions for almost all types that they are complex and expensive, but there are also simpler turbine technologies, such as the Archimedes screw and water wheels. The drawback is: they have lower efficiency. These technologies can be useful when the potential yield is not so large, like limited flow and/or low head (e.g. micro-hydro, local or private supply). Then a cheaper, simpler solution can be beneficial, as a larger investment in a more sophisticated technology will not pay itself back (low or no return on investment).