The new multi-rotor wind turbine: 3 blades good, 12 blades better

Cleantechnica

Hmm…We’re going to take a wild guess that the new multi-rotor wind turbine design from Vestas is going to encounter some headwinds when it comes to site selection. The single tower bristles with 12 blades mounted on four separate rotors, adding a new level of aesthetic concern to the issues already faced by today’s generation of tall wind turbines.

However, it’s a big world out there. If Vestas can prove that its new multi-rotor design ups the efficiency ante on wind energy harvesting, the big-picture result could be improved opportunities to locate wind farms without disrupting nearby stakeholders.

vestas 1

The New Vestas Multi-Rotor Wind Tower Design

The new wind turbine design first sailed across the CleanTechnica radar last spring, when Vestas announced that it was beginning installation of the behemoth at the Risø test site of the Technical University of Denmark near Roskilde. In collaboration with the University, the plan was to break the “scaling rules” on cost-efficient wind turbines.
Vestas has been keeping relatively quiet since then, but it finally provided an update last week on Facebook, when the multi-rotor concept produced its first kilowatt-hour. Apparently the company was so excited about switching on the equipment that it could not wait for a formal press release. Here’s the meat of the post:

Looking ahead, the extensive tests of the concept turbine’s functionality will continue: “Right now we are testing various software functions. One of them is the cut-out functionality, i.e. if the concept demonstrator stops when it reaches the cut-out wind speed. Another one is the yaw system supervision that shuts down the turbine in case the yaw misalignment exceeds certain values,” explains Erik Carl Lehnskov Miranda, Senior Specialist, Electrical, Load & Control at Vestas.

If you caught that thing about “yaw,” that’s a nautical reference for unintentionally pitching to the left or right.

Take another look at that photo up top and you can see how why minor glitch in one of the turbines would need to be offset ASAP by adjustments to the others, so realtime monitoring and correction is critical to the success of the project.

The risk factor could account for why the company is being rather cautious about equipping the new turbine. Rather than hanging its current generation of nacelles on the tower (nacelles refers to the enclosures for the working parts of the turbine), Vestas has furnished the turbine with four 1990’s era V29-225 kilowatt nacelles modded out with new controls and other features required for testing.

Speaking of site selection, turbines at the test site are limited to 74 meters, which explains why the new turbine clocks in at only 74 meters.

By way of comparison, in 2014 Vestas introduced a “taller” tower for low-wind locations which comes in at more than 140 meters.

Levelized Cost Of Wind Energy Goes Boom

The cost of transporting tall wind turbine towers accounts for a big chunk of the cost of wind energy compared to other sources (aka the levelized cost of wind energy). If the multi-rotor approach works, then the tower transportation costs can be spread out over more rotors, bringing the levelized cost of wind energy down.

Here in the US, wind already began crowding out coal in 2011, with a significant assist from low natural gas prices. With additional cost and efficiency gains, it looks that kind of help won’t be needed for long.

At its launch last summer, President Obama’s Clean Power Plan dropped some huge hints that renewable energy will be the face of the future, crowding out natural gas.

Presumptive Democratic nominee for president Hillary Clinton has also made it clear that if she wins the General Election this fall, opportunities under her Administration for new natural gas wells (specifically, those using hydrofracturing technology) will be few and far between — if new standards for public health and environmental impacts are adopted.



Stay tuned, because the Interior Department is already working on a review of the federal coal program, which could end up folding public health and environmental concerns into the cost of new leases and royalties for coal extraction on federal property.
Source: Cleantechnica. Reproduced with permission.

Comments

8 responses to “The new multi-rotor wind turbine: 3 blades good, 12 blades better”

  1. Chris Fraser Avatar
    Chris Fraser

    Four turbines to one post would be very efficient, and I rather like the look of them. What do you think Nick and Joe ?

    1. Mike Dill Avatar
      Mike Dill

      Might be efficient, but it will be 4x the maintenance. Might be rational where the heights are restricted.

      1. Chris Fraser Avatar
        Chris Fraser

        Hi Mike the maintenance for each nacelle would be unchanged. Although consider wind farms where the number of towers is reduced to a quarter of the original capacity, and potential reduction of visual impact.acknowledging all the while that visual impact is a qualitative concept. It’s new and different, a test site in a low valley with a few of these installed could be ideal.

  2. Brunel Avatar
    Brunel

    How does it look from a distance.

    These might be ugly compared to the normal ones.

  3. DogzOwn Avatar
    DogzOwn

    Do we do “ugly” any more? How much more elegant could you get than this class of gadget? Big fuss merchant was Smugly Joe Hockey but surely he’s RIP until he returns from land of the Trumpmeister?

    1. Miles Harding Avatar
      Miles Harding

      He’ll be vomiting cigar butts when he sees these.

  4. Miles Harding Avatar
    Miles Harding

    Off topic, but does this mean we can launch a class action against the anti-wind lobby for suppressing a technology that will save us all money?

    1. BrianLandon Avatar
      BrianLandon

      lol in Ontario Canada it produces 1.3% of all energy, and because folks there is no such thing as dilithium or crystal storage(100 years away), that energy is sold off at 1/2 price to neighbouring states and provinces. Oh, why don’t they put it downtown in the cities along the waterfront? Because of the noise level and the medical issues! Gotta love the downtown set who think money grows on trees um, turbines! So 100% taxpayer subsidies making Ontario the most expensive energy cost in North America.

      oh its also contributing to the deaths of species such as bats and some types of birds.

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