You can imagine a world where the efficiency of a more traditional turbine setup (measured in watts/$ including amortized capital and operating cost) scales down badly as hydraulic head decreases, and in fact is scales more poorly than the amount of power available.
What you're left with are scenarios where there's room for you to perform more efficiency than a traditional turbine if you can somehow get different scaling characteristics.
The economic viability becomes even more complex once you start considering things like what type of distribution you're dealing with.
Questions like, is it more efficient overall to have more distributed, but less efficiency generating sources, with reduced distribution costs, or have fewer more efficient generating sources with increased distribution costs.
I'd agree that in more of North America and Western Europe, this probably doesn't make sense. But there's still lots of places where the cost of hooking up to the grid is substantial.
You can imagine a world where the efficiency of a more traditional turbine setup (measured in watts/$ including amortized capital and operating cost) scales down badly as hydraulic head decreases, and in fact is scales more poorly than the amount of power available.
What you're left with are scenarios where there's room for you to perform more efficiency than a traditional turbine if you can somehow get different scaling characteristics.
The economic viability becomes even more complex once you start considering things like what type of distribution you're dealing with.
Questions like, is it more efficient overall to have more distributed, but less efficiency generating sources, with reduced distribution costs, or have fewer more efficient generating sources with increased distribution costs.
I'd agree that in more of North America and Western Europe, this probably doesn't make sense. But there's still lots of places where the cost of hooking up to the grid is substantial.