5 ms·

This is only partially related to my other long post here, but it should be mentioned. This article appears to be largely about potential to disrupt the wind in

by scblock 10y ago

This is only partially related to my other long post here, but it should be mentioned. This article appears to be largely about potential to disrupt the wind industry with outside the box thinking. But in the more than a decade I have been working in this industry the single most disruptive change in project performance was targeting low wind speeds rather than high, and accepting that turbines will have to shut down in higher winds. The main way this is achieved is to take a huge rotor and put it on a small generator. More energy is lost at high winds, but the ramp up from no generation to maximum is much faster. Since most projects spend the majority of their time along that ramp rather than at rated power this results in large gains in annual energy. This means that some sites once considered to be marginal to end up being good to very good. One area I've been working in saw a more than 25% increase in predicted energy for the same capital cost with the new turbine types.

beat 10y ago
Wind power is still largely a greenfield industry. There's no point in putting expensive (and risky) effort into suboptimal sites when so many optimal sites are still unexploited. Cringely's assumption that new designs aren't being tried because the industry is stupid is almost certainly wrong. More likely, they're still going after the low hanging fruit, and will start optimizing design for suboptimal locations once they've fully exploited the optimal ones. But there's a lot less profit in using more expensive turbines to harvest less wind.
- scblock 10y ago
  There are a number of companies and people working on potentially innovative ideas, but it's not an easy thing. Serrated trailing edges and vortex generators are easy enough to test (reduced noise from one, increase energy from the other). Others such as shrouded turbines, or multi-segment blades are difficult. Another thing vendors are doing now is purposefully running generators beyond their design at higher wind speeds (getting 2.2 MW from a 2.0 MW generator, for example), provided that other operating parameters are measured to be within range. This is usually driven by cooling requirements.
  - beat 10y ago
    Right. It's a diverse industry with the chance to make some very large money over the next few decades and beyond. The engineering efforts are fascinating. So when Cringely rolls his eyes and smirks at those conventional wisdom know-nothings ignoring the genius of his buddy... well, I suppose it's about what I expect from Cringely.
    - dmix 10y ago
      This over-confidence in your ability to change an industry is a good trait IMO. It powers entrepreneurial activity. While his hypothesis might be wrong in full implementation, it's possible there is some partial innovation here that could come out of testing out this idea. It's possible the constraints faced by large wind mills are not the same for smaller ones, for example. It's easier to dismiss radical thinking than to continually pursue them in the face of pervasive dismissiveness.
      - beat 10y ago
        Radical improvements aren't generally from minor refinements.
  - LoSboccacc 10y ago
    time for this https://en.wikipedia.org/wiki/Evolved_antenna https://en.wikipedia.org/wiki/Evolved_antenna but with fields of turbines as a system
- jcoffland 10y ago
  But your assumption that the industry is already doing the right thing is exactly what the article is speaking out against. Personally I don't know but I do believe there is a lot of value in questioning conventional wisdom.
  - mixmastamyk 10y ago
    Further, some empirical data would be nice. A few different configurations in different areas over a year would be a good start. These may exist but I've not yet seen them.
- Animats 10y ago
  Wind power is still largely a greenfield industry. It's not. There are a limited number of good onshore wind sites near big loads. California has only four good sites, and they all have big wind farms. There are lots of sites with enough wind northward from the Texas panhandle, but no big loads within a thousand miles.
Grishnakh 10y ago
I'm not in the wind industry and am not a ME, but rather a EE, but why couldn't you build a big vertical-axis wind turbine and then couple that to multiple generators, a big one and a small one, with gearing that lets the windmill drive either one? Then in low winds, you can drive the small generator at its optimal speed range, and then in high winds, you can switch over to the big generator and drive it at its optimal speed range (the small generator is decoupled in this mode). Obviously, this would be much more costly because of the additional big generator and the complication of the drivetrain. But it'd let you harvest a bunch of energy when it's really windy. And with a vertical-axis mill, not only would this be better for wildlife (lower overall speeds), the generators would be on the ground, not way up in the air, and driven by a shaft from the mill through its tower, so servicing would be easier and the weight and size of the generators and the drivetrain wouldn't be an issue.
- iamgopal 10y ago
  There is a very easy idea to achieve this, like the way tesla did to its induction motor, just use multiple windings.
- brandmeyer 10y ago
  I think you've misunderstood the innovation. The innovation in using a generator that is smaller than the blades and tower are capable of supporting isn't in the light-load efficiency of the generator. Its in the lower capital cost of the electrical system.
- scblock 10y ago
  For horizontal axis turbines two speed generators were historically a thing, usually with two sets of windings which were engaged at different speeds. This works, but is less efficient and mechanically more taxing on the machine than variable speed, variable pitch angle systems.
- Bartweiss 10y ago
  From a perspective a little closer to the industry, I think the answer is just "costs". This idea has higher turbine costs (and site profitability already ranges from impressive to deeply marginal), and the extra profit from the high end isn't excellent. Cringely overstates the money lost in high-wind conditions - most shutdowns are for low wind or to avoid damage in storm conditions, which are rather different than smooth, profitable high wind. Further, it might offer major operating-cost hits even with ground-based generators simply by being a major break with existing systems. Obviously that's surmountable, but it means that the system has to be better for a lot of sites to be worthwhile. That said, there are definitely vertical mill projects in the works, and I wouldn't be surprised if some of them have switchover generators.
scblock 10y ago
I just can't leave well enough alone, and did a quick and dirty very high level analysis: For a low to middling wind site in the US, with a 7.5 m/s average wind speed represented by a Rayleigh distribution: Using a GE 1.5-77, the most common turbine in use in the US in the late 2000s, I calculate 40.5% gross capacity factor, and estimate net capacity factor of 33.5%. Using a GE 2.0-116, one of the most energetic turbines on the market for low-wind sites, I calculate a 53.2% gross capacity factor, and estimate a net capacity factor of 44.1% using the same annual loss parameters as before. For a hypothetical project of equivalent size we get over 30% more energy every year from the same wind by only changing from the old technology to the new, and we build less infrastructure to support it. The new machines are taller, and we probably need the same amount of total land for the project.
e12e 10y ago
On the note of "innovation", looking for the term for vertical turbines, I came across this article from 2011: "Changing Winds: The Evolving Wind Turbine": http://www.powermag.com/changing-winds-the-evolving-wind-turbine/?printmode=1 http://www.powermag.com/changing-winds-the-evolving-wind-tur... It has (what appears to my untrained eye to be) a quick overview of various designs. To me it seems that vertical turbines makes a lot of sense - if for no other reason than it would seem like most of those designs get you more "turbine" for your build-costs/materials (and less "inert tower").

by scblock 10y ago

beat 10y ago

Wind power is still largely a greenfield industry. There's no point in putting expensive (and risky) effort into suboptimal sites when so many optimal sites are still unexploited. Cringely's assumption that new designs aren't being tried because the industry is stupid is almost certainly wrong. More likely, they're still going after the low hanging fruit, and will start optimizing design for suboptimal locations once they've fully exploited the optimal ones. But there's a lot less profit in using more expensive turbines to harvest less wind.

scblock 10y ago
There are a number of companies and people working on potentially innovative ideas, but it's not an easy thing. Serrated trailing edges and vortex generators are easy enough to test (reduced noise from one, increase energy from the other). Others such as shrouded turbines, or multi-segment blades are difficult. Another thing vendors are doing now is purposefully running generators beyond their design at higher wind speeds (getting 2.2 MW from a 2.0 MW generator, for example), provided that other operating parameters are measured to be within range. This is usually driven by cooling requirements.
- beat 10y ago
  Right. It's a diverse industry with the chance to make some very large money over the next few decades and beyond. The engineering efforts are fascinating. So when Cringely rolls his eyes and smirks at those conventional wisdom know-nothings ignoring the genius of his buddy... well, I suppose it's about what I expect from Cringely.
  - dmix 10y ago
    This over-confidence in your ability to change an industry is a good trait IMO. It powers entrepreneurial activity. While his hypothesis might be wrong in full implementation, it's possible there is some partial innovation here that could come out of testing out this idea. It's possible the constraints faced by large wind mills are not the same for smaller ones, for example. It's easier to dismiss radical thinking than to continually pursue them in the face of pervasive dismissiveness.
    - beat 10y ago
      Radical improvements aren't generally from minor refinements.
- LoSboccacc 10y ago
  time for this https://en.wikipedia.org/wiki/Evolved_antenna https://en.wikipedia.org/wiki/Evolved_antenna but with fields of turbines as a system
jcoffland 10y ago
But your assumption that the industry is already doing the right thing is exactly what the article is speaking out against. Personally I don't know but I do believe there is a lot of value in questioning conventional wisdom.
- mixmastamyk 10y ago
  Further, some empirical data would be nice. A few different configurations in different areas over a year would be a good start. These may exist but I've not yet seen them.
Animats 10y ago
Wind power is still largely a greenfield industry. It's not. There are a limited number of good onshore wind sites near big loads. California has only four good sites, and they all have big wind farms. There are lots of sites with enough wind northward from the Texas panhandle, but no big loads within a thousand miles.

Grishnakh 10y ago

I'm not in the wind industry and am not a ME, but rather a EE, but why couldn't you build a big vertical-axis wind turbine and then couple that to multiple generators, a big one and a small one, with gearing that lets the windmill drive either one? Then in low winds, you can drive the small generator at its optimal speed range, and then in high winds, you can switch over to the big generator and drive it at its optimal speed range (the small generator is decoupled in this mode). Obviously, this would be much more costly because of the additional big generator and the complication of the drivetrain. But it'd let you harvest a bunch of energy when it's really windy. And with a vertical-axis mill, not only would this be better for wildlife (lower overall speeds), the generators would be on the ground, not way up in the air, and driven by a shaft from the mill through its tower, so servicing would be easier and the weight and size of the generators and the drivetrain wouldn't be an issue.

iamgopal 10y ago
There is a very easy idea to achieve this, like the way tesla did to its induction motor, just use multiple windings.
brandmeyer 10y ago
I think you've misunderstood the innovation. The innovation in using a generator that is smaller than the blades and tower are capable of supporting isn't in the light-load efficiency of the generator. Its in the lower capital cost of the electrical system.
scblock 10y ago
For horizontal axis turbines two speed generators were historically a thing, usually with two sets of windings which were engaged at different speeds. This works, but is less efficient and mechanically more taxing on the machine than variable speed, variable pitch angle systems.
Bartweiss 10y ago
From a perspective a little closer to the industry, I think the answer is just "costs". This idea has higher turbine costs (and site profitability already ranges from impressive to deeply marginal), and the extra profit from the high end isn't excellent. Cringely overstates the money lost in high-wind conditions - most shutdowns are for low wind or to avoid damage in storm conditions, which are rather different than smooth, profitable high wind. Further, it might offer major operating-cost hits even with ground-based generators simply by being a major break with existing systems. Obviously that's surmountable, but it means that the system has to be better for a lot of sites to be worthwhile. That said, there are definitely vertical mill projects in the works, and I wouldn't be surprised if some of them have switchover generators.

scblock 10y ago

I just can't leave well enough alone, and did a quick and dirty very high level analysis: For a low to middling wind site in the US, with a 7.5 m/s average wind speed represented by a Rayleigh distribution: Using a GE 1.5-77, the most common turbine in use in the US in the late 2000s, I calculate 40.5% gross capacity factor, and estimate net capacity factor of 33.5%. Using a GE 2.0-116, one of the most energetic turbines on the market for low-wind sites, I calculate a 53.2% gross capacity factor, and estimate a net capacity factor of 44.1% using the same annual loss parameters as before. For a hypothetical project of equivalent size we get over 30% more energy every year from the same wind by only changing from the old technology to the new, and we build less infrastructure to support it. The new machines are taller, and we probably need the same amount of total land for the project.

e12e 10y ago

On the note of "innovation", looking for the term for vertical turbines, I came across this article from 2011: "Changing Winds: The Evolving Wind Turbine": http://www.powermag.com/changing-winds-the-evolving-wind-turbine/?printmode=1 http://www.powermag.com/changing-winds-the-evolving-wind-tur... It has (what appears to my untrained eye to be) a quick overview of various designs. To me it seems that vertical turbines makes a lot of sense - if for no other reason than it would seem like most of those designs get you more "turbine" for your build-costs/materials (and less "inert tower").