Is wind energy’s future bladeless?

Posted: April 26, 2013 by tallbloke in Energy, wind

From the “Why didn’t we do some more R&D before carpeting the country in useless bird killing machines” department:

saphon-bladeless-wind-energy-source-saphon

The Saphon device wobbles in a 3D knot shape generating electricity via pistons at the same time (Source: Saphon)

A Tunisian wind energy startup says it is in talks with a number of major industrial players as it looks to move its bladeless wind towers to a commercial scale.

Saphon Energy’s sail inspired towers wobble in the wind, with pistons converting kinetic energy to electricity. It says that by removing blades and gearboxes it can “comfortably” reduce the cost of wind energy by 25%.

Empirical tests it has conducted suggest bladeless wind devices could be 2.3 to 2.5 times more efficient than three-blade turbines, capturing about 60-70% of the wind’s kinetic energy.

The absence of rotating blades and a gearbox makes the technology possible at any scale says Labaied. The bladeless technology also means less noise, no risk to birdlife and easier installation.

By using the same power-producing pistons to store hydraulic pressure instead of generating electricity, the towers can store energy without needing a battery. The built-up pressure can be released slowly when the wind is not blowing to even-out the supply of power.

Read the rest here

Comments
  1. When conventional wind follies are producing less than 0.0% energy, at low wind speeds these devices would produce 2.5 times more?

  2. tallbloke says:

    Hi Fen. The claim is:
    “Empirical tests it has conducted suggest bladeless wind devices could be 2.3 to 2.5 times more efficient than three-blade turbines, capturing about 60-70% of the wind’s kinetic energy.”

    That’ll happen above some minimum speed.

  3. hi Roger……It’s the minimum speed that’s the main issue. 😀

  4. tallbloke says:

    Fen: Sure. However, this invention claims the possibility of stored energy without resorting to batteries. Hydraulic accumulators are well tried and trusted old technology. My Old dad has just been telling me about Manchester Waterworks system in the 1950’s which powered lifts in the city centre hotels. Capital investment is high for the return in energy terms though.

  5. A C Osborn says:

    Someone did some lateral thinking, if it is better than a turbine then it may have some useful applications even if it may not work for Main Grid power.

  6. Joe Public says:

    With pistons, seals, cranks, conrods, bearings, pressure-relief valves etc, maintenance costs & long-term reliability must be issues.

  7. tallbloke says:

    Good point Joe P. Coal fired boilers and steam turbines need maintaining too, though they produce a lot more energy per pound spent on maintenance than any renewables involving moving parts.

  8. Low winds across the whole country can last for weeks Roger. This was particularly the case in 2010. This technology does not have the storage solution for that problem. This is not a significant energy solution for the UK. They will suffer also from the same problems the propeller sticks suffer from in the UK. (A lack of places to put them). Too much land required to produce too little. Cost and reliability issues if placed out to sea….As well as environmental and negative visual effects even when out to sea.

    …..Have you been to Skegness recently?

  9. tchannon says:

    There are lots of other methods and ways of doing it. As usual almost all of them are bad, including scams fools and money. My immediate reaction on reading the text above is, it’s a scam.

    Don’t sign anything..

  10. tallbloke says:

    Fen: I agree this isn’t a solution for a substantial proportion of the UK’s needs. These Tunisian guys have in mind village scale generation in African regions with no grid. Some remote hill farms in the UK could benefit too.

  11. hunter says:

    60 +% is going to disrupt the wind significantly.
    Wind power is bad news, bladeless or not.

  12. tallbloke says:

    OB: Looks like the ‘wind lenses’ would add greatly to the strength required in the tower structure. Vertical axis designs VAWT’s mae more sense for urban environments. Quieter, not affected by sudden wind direction changes, and a lot less dangerous.

    http://www.quietrevolution.com/qr5/qr5-turbine.htm

  13. oldbrew says:

    TB: yes, they already say…

    “Wind load on the wind-lens turbine is larger than [on] typical wind turbines; application of the wind lens to turbines in larger sizes faces structural challenges.”
    http://kapionews.kapiolani.hawaii.edu/wind-lens-proves-useful-for-hawai%CA%BBi/

  14. Doug Proctor says:

    The problem with windmills is that the blades move quickly on the outside, giving them an invisibility, power for good bird chopping, and a speed limit for structural integrity. The power invested in the blades is distributed along the blade.

    What if you used a torus instead, with a crankshaft at the bottom like an overshot waterwheel, so that the wind’s energy is invested in a large diameter but small cross-section rim (at any given point) that doesn’t move so fast but is transfering a lot of total power to the crankshaft.

    Instead of propellers on towers, you have rings on towers with a central vane that can turn the ring into the wind while giving structural support to the ring but not turning itself.

    Clearly this has been investigated, and you guys know the answer …..

  15. tchannon says:

    The fundamentals of airscrews (and marine) etc. are known in great detail so I wouldn’t worry about basics being wrong in that respect but there is a higher level of consideration which is a problem.

    Given the objective of extracting energy from a boundary layer the issue is then somewhat altered.

    There is not one unit but many. All these are operating in a turbulent boundary layer where wind speed varies with altitude. Direction varies too. Typically there are also support structures making life even harder.

    Hence the output from a farm is much lower than for an isolated unit.

    Now what is an optimisation?

    Some promote vertical axis as better.

    At a higher level still, what is the point given we know how to produce electricity rather more effectively.

    My personal opinion is the facility should be reliable and invisible. This suggests ducted with anything moving hidden. What is low key visible is directing the air.
    I admit to an interest, I’m unusually sensitive to anything which moves. (which causes lots of trouble for me with everyday things. people vary on this so whilst it is unusual it is far from rare. the origin is probably evolutionary where we are constantly scanning for movement, prey or predated)

  16. J Martin says:

    I think eventually the vertical axis wind turbines will eventually become the standard windmill.

    http://www.tangarie.com/products/gale_vertical_axis_wind_turbine.php

    And that they are likely to encompass a wide range of designs.

  17. Roger Andrews says:

    TB: “this isn’t a solution for a substantial proportion of the UK’s needs. These Tunisian guys have in mind village scale generation in African regions with no grid. Some remote hill farms in the UK could benefit too.”

    All you need to make renewable energy economic for small-scale applications is a) exorbitant power costs, which here in Mexico we have (40c US/kwh is about the same as Denmark) and b) an abundant source of renewable energy, which we also have (20N latitude + 1,500m elevation = lots of sunshine.)

    So last week we installed seven 250w solar panels. We are told that over their 25-year warranted life they will cut our CO2 footprint by 46.33 tons, save 128.81 trees and/or have the impact of taking 7,233.55 cars off the road. But while we remain deeply conscious of the desperate need to save the planet from CAGW this wasn’t why we installed them. We did it for the money:

    Installed cost of panels: $US 6,530
    Annual electricity savings: $US 970
    Payback: 6.7 years.

    And no subsidies involved either,

  18. Curious George says:

    Roger – kudos to your enthusiasm. Unfortunately, your numbers don’t look right. Less than 2kW of peak solar power would take 7 thousand cars off the road? For 25 years, presumably? Do you need any electricity at a night time? Did you get your batteries (or inverters, if you sell your 1.75kW to a power utility) for free?

  19. Roger Andrews says:

    Curious George: The numbers don’t make much sense to me either (which is why I said “we were told”). I’ll check with the installer to see where they came from – I suspect it was the solar company blurb sheet. In fact I’m beginning to wonder how many solar installations are being sold purely on the basis of the green propaganda the installation quotes come accompanied with.

    We don’t have batteries – just a 2.5 kw inverter and a digital meter with a reverse gear. The savings occur because the meter runs backwards often enough to lower our bi-monthly consumption from the heavily-penalized bloated plutocrat range down into the heavily-subsidized poverty-stricken range. The free market in action again.

  20. Curious George says:

    Roger, thanks. May your savings be for real.

  21. RACookPE1978 says:

    Off grid, remote villages could well benefit from this …. BUT we need to run them for a while.

    One tremendous advantage that turbine-generators and diesel trains have over the old steam locomotives is reliability and maintenance (often linked) and economical operation over both the long and short term. That is, each day, you needed a lot of time and manpower to get a steam locomotive heated up, oiled, greased, inspected and ready-to-run. Each night, more time is needed before the engineer and crew could leave. The “slamming” of pistons and the whole drive train at the end of each stroke means more long-term wear at high speeds on all of the moving parts 9pistons, valves, links, running gear, axles, timing cams, reverse gears, engine frames, bearings, boilers, etc. A smoother-running diesel, whose pistons are much lighter, much smaller turning a electric generator that turns electric motors between each axle, is much faster to start, run, stop, and operate on a day-to-day basis, and runs much longer between long-time maintenance periods. Almost as soon as turbines became practical in the first years of the 20th century, they replaced stem (pistons) engines in the world’s powerplants because of efficiency, smoother (constant turning) operation, higher speeds, and lower maintenance.

    Here, can the pistons and linkages hold up over long enough periods to be economical?

    Maybe, maybe not. But if your isolated village has nothing, and can get something for even a short (10 year-15 year time) that works part of the time – you have gained something worth investigating. Current wind turbines are less than 23% effective against nameplate rating. (Ranting ?) Any gain over that number will help.

    But reliable on-grid power will ALWAYS beat off-grid … as long as the on-grid power is in place. A transmission line in the states to a remote building or farm or site can be over $10000.00 per mile, depending on permits and enviro approval. Doesn’t take long before “unreliable” off-grid power becomes attractive.

  22. Stephen Richards says:

    It doesn’t change the fact that windmills and solar panels are intermittent suppliers and utterly, utterly useless without cheap efficient storage.

  23. dave ward says:

    “All these are operating in a turbulent boundary layer where wind speed varies with altitude”

    Having flown a microlight from a farm strip near the coast I am only too aware of this! Inversions at between 3-600ft AGL were quite frequent, and would mean typical large turbine blades suffering considerable variations of loading as they turn. If the machine was oriented into a prevailing Westerly (as sensed at the top of the tower), the tips could suddenly be faced with an Easterly, and 5-10 degrees difference in temperature in the top third of their arc…

  24. peter_dtm says:

    this is the bit that got me

    quote
    By using the same power-producing pistons to store hydraulic pressure instead of generating electricity, the towers can store energy without needing a battery. The built-up pressure can be released slowly when the wind is not blowing to even-out the supply of power
    end quote

    So where are they going to build the dam to store the water to all the ‘slow release of ”presure”’ ?

    Here’s an example of what is needed for a mere 1800MW for 6 hours :

    https://en.wikipedia.org/wiki/Dinorwig_Power_Station

    So as usual; the limiting factor for wind turbines (or wind oscilators ?) is our inability to store power; not our inability to generate it (regardless of whether CO2 reduction is required or not)

  25. RACookPE1978 says:

    I work with high pressure hydraulic systems every day in the power plant world: They are nasty, dangerous, and very tricky systems that require a great deal of respect,a lot of maintenance, and precise maintenance, cleaning, and care (of the hoses, seals, pistons, oil, pumps, glands, etc.

    Yes, they can be built, run, and maintained. But don’t let EVER tell me to stand next to a pressurized hydraulic or air system capable of storing even a half-day’s worth of energy. When (not “if” but “when” it goes), it will be deadly. Messy. Destructive.

  26. tallbloke says:

    RA: I know. Pumped storage is the safer option, but artificial mountains are pricey in flat areas.

  27. Sleepalot says:

    @ R. Andrews. How much is 0.01 trees?