
In-River Hydro-kinetics
When rivers are utilized to produce electricity, that is usually accomplished by building some sort of hydroelectric dam, like the three we discussed earlier. It doesn’t have to be that way, however. Many of the technologies used to extract energy from the tides (or similar technologies) could be deployed in freshwater river systems rather than the saltwater ocean, effectively acting as very small run-of-river facilities. These “hydrokinetic” power generation systems are typically individually small (each generating about 100 kilowatts or less of power) and could be situated in two ways. First, a propeller-like or turnstile-like turbine could be deployed directly into the riverway, operating much like a small-scale tidal power system. Second, a “micro-hydro” type of system could be employed, where river water is channeled to a turbine housing via a channel or pipeline, as shown in the figure below.

The image is a diagram illustrating the components of a run-of-the-river hydroelectric power system set in a hilly landscape.
- Intake: At the top right of the diagram, there is a structure labeled "Intake" located in a river, where water is diverted from the natural flow.
- Canal: From the intake, water is channeled through a man-made waterway labeled "Canal," which runs along the contour of the land.
- Forebay: The canal leads to a wider section labeled "Forebay," which serves as a small reservoir or settling basin to regulate water flow before it enters the penstock.
- Penstock: Water from the forebay is then directed into a large pipe labeled "Penstock," which slopes downward, carrying water under pressure to the power station.
- Powerhouse: At the bottom left of the diagram, there is a building labeled "Powerhouse," where the penstock delivers water to turbines. This is where the conversion of water energy into electrical energy occurs.
- River: The natural river continues to flow beside the canal and penstock, with the powerhouse situated near the riverbank. The river is depicted winding through the landscape, with some water being diverted for power generation.
- Landscape: The background includes hills and trees, indicating a natural setting. There's also a small house near the river, suggesting human habitation in the vicinity.
The diagram uses simple lines and labels to show the flow of water from the river through the intake, canal, forebay, and penstock to the powerhouse, illustrating how run-of-the-river hydroelectric systems work by utilizing the natural flow of the river with minimal storage.