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>This turbine is an interesting concept for illustrating fluid mechanics, but I think trying to spin it as a good alternative for a new hydroelectric turbine ty

>This turbine is an interesting concept for illustrating fluid mechanics, but I think trying to spin it as a good alternative for a new hydroelectric turbine type is ultimately misleading. Well, if you watch TFV they show a working prototype at around the 6min mark. So it's clearly a concept worth investigating further for use as a power source. Incidentally, your comment is the type of "middlebrow dismissal" that plagues this site. You picked one small explanatory point from a relatively poorly written article, disputed it with a source from Wikipedia, and concluded by dismissing the subject of the article, an engineer's highly promising work. [Edited]

kbenson 10y ago
> Piss off with your "middlebrow dismissal". And that's where you went from being part of the solution to being part of the problem.
- reneherse 10y ago
  You're right; thank you. On reflection I edited my response for tone. (I get fired up the way people's good work sometimes gets treated.)
semi-extrinsic 10y ago
I'm sorry if my comment appears too "middlebrow dismissal". My dayjob is working as a fluid mechanics researcher, and I have colleagues who work on hydropower turbine design. And I did watch the video, hence my comments about viscous losses. My point being that I know turbine design is an extremely well-understood and mature field, I didn't just google it. Also, as you say they've built a prototype to test the result. To be taken seriously, they should have also put a few students on the task of building a similarly sized Kaplan turbine and then compared the efficiency. It would have been very simple; there are probably even scale model Kaplan turbines that you can buy for this purpose. (It's basically just a propeller in a tube.) TFA is a bit like an SW dev coding up a new webserver, claiming it solves a case where existing ones do poorly, but then not bothering to benchmark it on that case against, say, Apache or Nginx. Finally, the big challenges in hydropower are not in increasing efficiency or lowering cost. The challenges are that we've interrupted/dammed most large rivers already, and any new plans to build hydropower face great resistance both from NIMBYs and environmental protection groups.
- reneherse 10y ago
  >Finally, the big challenges in hydropower are not in increasing efficiency or lowering cost. The challenges are that we've interrupted/dammed most large rivers already, and any new plans to build hydropower face great resistance both from NIMBYs and environmental protection groups. That's what makes this new turbine such a brilliant fit for our times: it can work at a small, distributed scale that to my knowledge hasn't been possible with hydro before, and at significantly reduced capital costs. Additionally, there are hardly any moving parts. Of the pieces that are required, they are intrinsically durable and easy to manufacture shapes, suitable for manufacture in relatively low-tech economies. BTW, thanks for clarifying your initial response.
- nate_meurer 10y ago
  This is exactly the sort of comment that keeps me coming back to hacker news. Thank you for it.

kbenson 10y ago

> Piss off with your "middlebrow dismissal". And that's where you went from being part of the solution to being part of the problem.

reneherse 10y ago
You're right; thank you. On reflection I edited my response for tone. (I get fired up the way people's good work sometimes gets treated.)

semi-extrinsic 10y ago

I'm sorry if my comment appears too "middlebrow dismissal". My dayjob is working as a fluid mechanics researcher, and I have colleagues who work on hydropower turbine design. And I did watch the video, hence my comments about viscous losses. My point being that I know turbine design is an extremely well-understood and mature field, I didn't just google it. Also, as you say they've built a prototype to test the result. To be taken seriously, they should have also put a few students on the task of building a similarly sized Kaplan turbine and then compared the efficiency. It would have been very simple; there are probably even scale model Kaplan turbines that you can buy for this purpose. (It's basically just a propeller in a tube.) TFA is a bit like an SW dev coding up a new webserver, claiming it solves a case where existing ones do poorly, but then not bothering to benchmark it on that case against, say, Apache or Nginx. Finally, the big challenges in hydropower are not in increasing efficiency or lowering cost. The challenges are that we've interrupted/dammed most large rivers already, and any new plans to build hydropower face great resistance both from NIMBYs and environmental protection groups.

reneherse 10y ago
>Finally, the big challenges in hydropower are not in increasing efficiency or lowering cost. The challenges are that we've interrupted/dammed most large rivers already, and any new plans to build hydropower face great resistance both from NIMBYs and environmental protection groups. That's what makes this new turbine such a brilliant fit for our times: it can work at a small, distributed scale that to my knowledge hasn't been possible with hydro before, and at significantly reduced capital costs. Additionally, there are hardly any moving parts. Of the pieces that are required, they are intrinsically durable and easy to manufacture shapes, suitable for manufacture in relatively low-tech economies. BTW, thanks for clarifying your initial response.
nate_meurer 10y ago
This is exactly the sort of comment that keeps me coming back to hacker news. Thank you for it.