Archive for the ‘Wind’ Category

[REPOST] Green Gone Wrong | Quiet Revolution VAWT Total Flop, Says German Paper

This article from my colleague Paul Gipe deserves a repost.

Quiet Revolution VAWT Total Flop, Says German Paper

I too knew years ago this well-intended Quiet Revolution technology was a flop. As a matter of fact, I knew five years ago, January 2011 to be exact. This is when a colleague who used to work for this company reached out to me regarding performance benchmarks, and to enquire about a tool/method to provide customers better information on small wind generators installed atop rooftops. Analyzing rooftop wind data from the Warwick Wind Trials, the first field trial investigating small wind turbine performance in the built environment, was the crux of my post-graduate research. Interesting, he left the company in 2013.

Here’s the rub on siting, VAWTs, HAWTs…


  • Location/Siting is PARAMOUNT.
  • VAWTs perform better if they too are mounted higher in smoothest, strongest wind, not near to the ground or close to the tops of buildings or other structures, natural canopies.
  • VAWTs blades are prone to fatigue created by centrifugal forces as the blades spin around the central axis >> they are less reliable  than HAWTs.
  • VAWTs require large bearings at the tower top to permit the shaft to rotate and thick steel cable to supper them >> more costly, especially when repairs and maintenance are needed.
  • VAWTs are less reliable and less efficient that HAWTs, and made worse if they are mounted at ground level or on top of buildings.
  • Raising a wind turbine, be it HAWT or VAWT,  into the smoothest, strongest wind ensures greater electrical production and longer machine life.

TWO | VAWT [Vertical Axis Wind Turbine]

  • Powered by wind coming from 360 degrees; does not need to be pointed into the wind; advantage where wind is highly variable.
  • Lower TSP [Tip Speed Ratio].
    Lower operating RPM (rotational speed) >> higher torque, requires a bigger, more massive generator + gear box (drive train) >> lowering efficiency.
  • Inherently lower Cp [Coefficient of Performance].
  • 360 degree rotation on aerofoil w/in wind flow each cycle >> high dynamic blade loading, pulsating torque on drive train, difficult to model wind flow accurately.
  • Drive train more accessible, since it can be placed near ground.
  • Lower audible noise.
  • If mounted on a rooftop, building redirects wind higher over the roof, doubling wind speed at turbine if mounted on roof ~50% of building height (near optimum for max wind energy and minimum turbulence) >> noise could be an issue.
  • Requires a heavier, stronger rotor assembly due to increased torque, etc. + stronger, heavier tower due to increase in turbine mass >> accounting for 60%+ in total capital installation cost.

THREE | HAWT [Horizonal Axis Wind Turbine]

  • Larger swept area >> more energy produced.
  • Performance in turbulent wind not favorable.
  • Higher RPM >> more suitable for driving a generator.
  • Gearbox turns slow blade rotation into quicker rotation (steps up) for driving an electrical generator.
  • Rotor usually positioned upwind since turbulence (mast wake) produced behind tower.
  • Downwind rotors don’t require additional controls mechanisms for keeping in line with the wind.

Quiet Revolution VAWT


Alas, not another one…

I would appreciate it if these green fashionista inventors would AT LEAST do their research and learn from the mistakes of others. Case in point –the Portland, OR, USA Trimet Light Rail Station pole mounted small, kinetic architecture’ installation, er AKA Oregon Wind Revolution small wind turbine generators.

…will include 22 wind turbines mounted on top of the light-rail catenary poles. The turbines will provide 275 watts of power.

===> 12.5 watts per turbine. Who signs off on this kind of nonsense?!

You can’t read the rest of the aforementioned article, because it no longer exists. I wonder why…

And I have so many questions about this design:

  • Output voltage (VDC)?
  • Maximum wind speed  a single unit and wind tree can withstand?
  • Ballasting? How is this addressed for a veritable plethora of mounting scenarios? Roof parapet? Roof top? Near building?
  • What is the material of the rotor and blades?
  • Optimal gap between the blades?
  • Cp,max? [For a Hybrid = 0.24, this is the theoretical max power (called  Cp,max–maximum coefficient of power) available in the free stream of wind converted to mechanical power at the rotor axis for this configuration.]

As wind sage Paul Gipe said about this wind tree, “Darrieus himself would be embarrassed. c’est la vie.

The Oregon Wind Revolution [in the image below] is known as a Savonius design. The highest Cp,max [maximum coefficient of performance] is found w/a 2-bladed design w/a gap between the turning bodies of 0.1-0.15. Savonius rotor gap is higher than a drag-driven rotor, and uses high material.


Crimey! MORE Green Going Wrong | Ford to install wind and solar energy at dealerships


I just caught this today.

Ford to install wind and solar energy at dealerships

I couldn’t let this one go. Another installation of kinetic architecture. And so, blatted out the following on this post…

[POST #1]

I’m fairly certain the PV arrays will be the stars of producing the flow of electrons. And unless the wind turbines have been sited correctly, they will only be kinetic architecture ==> another green gone wrong installation by green fashionistas Wind Energy Corporation.

[POST #2]

As someone who performed post-graduate research of the performance of small wind turbines in the built environment, this installation is questionable at best. And just based on the photo, I’m pretty sure this installation was not sited well, which only gives small wind a bad name.

I also went to the vendor’s,  Wind Energy Corporation’s web site, and all I could locate was a single landing page. Red flag #1. I also searched for Jack Phillips on Linkedin and his background is only in accounting and int’l business, NOT computational fluid dynamics or mechanical engineering. Red flag #2.

Vertical Axis Wind Turbines (VAWTs) like the ones here, are NOT immune to turbulence. Rapid, turbulent low-level wind increases the fatigue on a VAWT just like an Horizontal Axis Wind Turbines (HAWTs). HAWTs are just as sensitive to changing wind direction and turbulence as VAWTs, especially if the turbine is installed on too short a tower.

Readers to this post should also know:

  • VAWTs perform better if they too are mounted higher in smoothest, strongest wind, not near to the ground or close to the tops of buildings or other structures, natural canopies.
  • VAWTs blades are prone to fatigue created by centrifugal forces as the blades spin around the central axis –> they are less reliable  than HAWTs.
  • VAWTs require large bearings at the tower top to permit the shaft to rotate and thick steel cable to supper them –> more costly, especially when repairs and maintenance are needed.
  • VAWTs are less reliable and less efficient that HAWTs, and made worse if they are mounted at ground level or on top of buildings. And the ones in this photo are clearly close to ground level.

Reference: Power from the Wind by Dan Chiras with contributions from Mick Sagrillo and Ian Woofenden.

It is a well-known fact that, by seasoned professional small wind turbine experts, VAWTs, like these are less efficient than HAWTs  and made worse by being mounted closer to ground level boundary level–the few advantages they offer cannot counter the many, fatal disadvantages sited so close to ground level.

Small wind turbine installations are not advised that do not meet the  best practices recommendation of at least 30 feet above the closest obstacle, er trees included, within 500 feet, and are well inside the turbulence bubble (vertically ~2xs the height of the obstruction/house(s) and downwind ~15x – 20x the height of the obstruction/house(s)). Raising a wind turbine, be it HAWT or VAWT,  into the smoothest, strongest wind ensures greater electrical production and longer machine life.

I would also encourage readers to focus more on the performance data vs power curve information. I realize that rated power of wind turbines/power curves was devised to provide customers a way to compare wind turbines. I think folks need to understand that its usefulness has been limited. After taking another look (since it was back in 2009 that I looked into performance data from the results of the Warwick Wind Trials), I see updated standards in the wind industry for determining rated power has been established for comparison across models i.e. 5 m/s [11 mph].

Perhaps the editor, James Murray will revisit this read and ensure the truth is told about this well-intended offering. Not holding my breath, especially because they keep deleting my posts. Yeah, well, you know…Fleh.



REST in Urban Agriculture

As the ‘indifference’ of Mother Nature, er climate instability continues intensifying, and when the price of petrol gets prohibitively expensive for foodstuffs to make their way to the markets, folks will be wishing for an achievable, sustainability developed schema like REST in Urban Agriculture  that includes:

  • hybrid renewable energy systems technology [HREST] for energy generation and capturing moisture from the air via atmospheric water generation
  • water resource management
  • waste management
  • affordable housing
  • access to fresh produce
  • employment opportunities
  • the 5 R’s – resiliency, redundancy, robustness, reliability, repair


Plan F :: I lament — Wondering if and when the Hybrid Renewable Energy Engineer job description will become a norm…

Some wonder why I persist in having such a difficult time landing work as a hybrid renewable energy engineer. Perhaps if I were of the business developer, marketing, sales or policy ilk, I’d have more work than I knew what to do with. But I am an R&D anomaly and not readily embraced. So, I need to continue to try to be patient to let people catch up.

One of my colleagues/mentors, the notable, internationally recognized renewable energy sage Paul Gipe shared the following affirmation with me several weeks ago about my attempt to heighten awareness about why community wind is needed at the LCEA Clean Power, Healthy Communities Conference in Oakland, CA. My presentation is here, but sadly, there was only a single party interested in my offering during the conference. Paul emailed me the following after the conference:

Subject: hang in there/you did good

Date: October 18, 2013 7:03:09 AM PDT

To: Kimberly King <>

hang in there kimberly. you did the right thing by coming out and making a presentation before the “solar only” crowd. it needed to be done, needs to be done, and needs to be done again and again–americans are slow learners.

but of course part of the problem is that we don’t have any policies that make it possible–and until we do we’ll just be working at the margins. . .


Yes, I have been on the margins since I embarked on this reinvention to become a hybrid renewable energy engineer back in 2001. And back then, I knew distributed generation would eventually become the order of the day. Thanks to SB 43 there is a smidgen of traction, but it’s still no slam dunk. Not to mention, I have touted distributed energy in the Interests section of my LinkedIn profile when I first launched my profile back in 2005

To obtain a challenging position developing hybrid renewable energy systems using sustainable development practices. Research and engineer hybrid renewable energy power micro-grid/nano-grid systems. Research mitigating noise generated by small wind turbines in the built environment. Make contributions developing hybrid renewable distributed energy power systems toward the development of renewable energy as part of the World Wide Energy Web. Engineer renewable energy efficiency designs.

It was because of my time holding leadership roles, developing solutions to problems in unknown territory, my capabilities as a Jill-of-all-trades generalist during the dot-com in IT/Systems Engineering/Administration, that Silver Spring Networks | UH-HNEI | DoE SunShot Initiative SmartGrid PV Inverter Project picked me up last year for a short-term, six month contract as a technical writer. One of the big reasons I was selected was due to my load flow analysis embedding ten wind turbine generators on an existing electrical distribution network paper as a part of my post-graduate degree. Mind you, this SunShot Initiative project is the cornerstone, benchmark communications protocol project for the USA for embedding a high-penetration of residential PV inverters on existing electrical distribution networks. This pilot’s aims are to discern how well the bi-directional flow of electrons from renewable energy generators can be managed by a utility. Most of the people I worked with on this project are ex-Cisco engineers, and found me to be a natural for this job. The reference letter from my supervisor is viewable here.

I was also in the queue for consideration under the Fraunhofer Institute/Sandia National Labs Micro-grid/Nano-grid project collaboration that was tabled indefinitely late last year. Thank you gov’t shutdown. *Sigh* And just a couple of months ago, I was in the queue to work on Chevron Energy Solutions/Chevron Renewable Power Division as a Investment Structuring Analyst/Associate for PV and geothermal plants, but these projects were placed on hold indefinitely as a result of the government shutdown.

Unfortunately, as time progresses, I feel more and more like hedged my bets incorrectly–thinking by now the renewable energy industry would have adopted the mindset that was pervasive during the dot-com to seek agile, adaptable engineers who are agitators, and who can wear more than one hat to get a job completed. Instead, this myopic vision I have come to witness over the past eight years seems to be the order of the day. This is out of my control. And so, I continue to be relegated to the margins/fringes. I am all for contingency planning. Sure always having a Plan B or Plan C makes sense, but I NEVER fathomed I’d need a Plan F. Let’s see how this all came about…

Plan AStarting in 2001, I volunteered at the Resource Renewable Institute, to learn more about this operatives renewable energy and sustainable development. I also performed due diligence for The Rahus Institute on why more PV systems were not being installed on K-12 schools in California. From 2004-2010, pursued academic coursework at a veritable plethora of universities in the USA, The Netherlands and the UK. I also completed PV Design and Installation coursework with Solar Energy International and at Diablo Valley College. For a year, I helped design and install solar PV systems on residences.  Eventually completed a post-graduate degree in renewable energy systems technology engineering in 2010 at the Centre for Renewable Energy Systems Technology (CREST) a part of Loughborough Technical University in the Midlands of the UK.

Plan BDue to the tumultuous, global financial climate in 2008, started having to fall back on my technical writing, computer science skills set–just like a number of my seasoned, professional CREST classmates had to do. Made the short list a number of times for a number of jobs–I lost count awhile ago. Chemistry. However, it’s an employers’ market and one has to meet 100% of the job description ‘check-box’ criteria, and getting past the HR ‘gate keepers’ these past few years has been inordinately challenging.

Plan C Started falling back on my chef skills as an Eco-chef; swapping my services for short-term housing, if pay was an issue.

Plan DDog sitting, House sitting to make trickle-in survival income while waiting for contractual engineering work to be finalized. These contracts never materialized.

Plan EJoined the SF Local 16 to obtain part-time freelance work in audio and visual realm, in an effort to get off the ‘food stamp diet.’

Plan F – My present aim is to secure a certificate in Industrial Maintenance [welding, machining, hydraulics] at Laney College, because our first world nation with a third world infrastructure is going to break HARD, and it will require having more talent who not only knows how to design, but also knows how to fix and tune, on-the-fly in the field.

I have some appointments coming up in December to chat with a CPUC [California Public Utilities Commissioner] to discuss why there persists in being consternation with supplier diversity issues. Also, more recently, a finance director at Chevron Energy Solutions has expressed some interest in hearing my ideas on how Chevron might participate in SB 43.

I am no Nikola Tesla, but I certainly have a great deal of empathy for the man, his vision and all the ‘brick walls’ he had to traverse to even get his ideas and designs embraced. Sadly, he was impoverished and in debt when he passed away. Alas…

To quote Randy Pausch,

Don’t ball. The best of the gold’s at the bottom of barrels of crap.

I sure hope so, because I’m borderline vanquished.


Community Wind Power in the SF Bay Area?? Ja, it’s needed…

Right-o. Earlier this week, I finished marking up a presentation story on why community wind power is needed in the SF Bay Area. It’s long. 50 pages. Working on the audio to go along with the slides here. Out think the box…


Community Wind Power in the SF Bay Area??

I just discovered, I don’t have any bla bla on this blog about community wind power generation. I’ve emailed volumes on this topic over the past two years. Ja, past time to post up some bla bla here…

I find it troubling community wind projects and discussions don’t seem to make way into the SF Bay Area proper. I mean this is the SF Bay Area, the bastion of being vanguards in furthering a mindful approach to maintaining a high quality of life. Makes me wonder if something I have been missing that is going on in the corridors of government that are hampering these kinds of opportunities. I mean Anheuser-Busch in Fairfield, Solano County has figured out how to make this work in their behalf alongside Foundation Windpower.

According to the American Wind Energy Association (AWEA):

AWEA Community Wind Projects in the USA

Wind energy projects that incorporate local financial participation and control are known as “community wind” projects. Community wind projects encompass a wide range of sizes and project types. Some examples include:

  • 1-kilowatt to 100-kilowatt net-metered home and farm-based systems
  • Mid-size singe-turbine projects at schools and businesses
  • Wind-diesel village power projects
  • Multi-megawatt wind farms owned by co-ops and munis
  • Wind farms comprising tens of megawatts and an independent power producer arrangement

NB: Since 2011, there have only been FOUR community wind projects to come on-line in CA. Whereas there have been sixteen in Iowa, twelve in Massachusetts and ten in Minnesota. The Hull, MA Community Wind Project is the most highly regarded.


Making Wind Power History :: Decommissioning a Aero Power SL 1500 wind turbine installed in 1981 in Berkeley, CA, USA

On 23 April 2013, I launched an indiegogo crowd funding campaign to raise funds to decommission a freewheeling, derelict 31 year 4 month old Aero Power SL 1500 in Berkeley, CA, USA. It’s taken the better part of a year to perform due diligence and build up a trust relationship with the homeowner of this small wind turbine. The case study can be read here.

Perhaps you reading this, and your organization might be interested in this information, and perhaps  including this announcement on your web site or other [social] media networks. 

Take a moment to check it out on Indiegogo [link is below] and also share it with your friends and colleagues.  All the tools are there. Get perks, make a contribution, or simply follow updates. If enough of us get behind it, we can make ‘Making Wind Power History’ happen!

The campaign only runs until Tuesday, 14 May 2013.

NB: I am in the process of compiling a comprehensive report on the steps taken to decommission this machine. I am donating the wind turbine to UC Berkeley’s Renewable and Appropriate Energy Lab [RAEL] for research and analysis.

Thanks for your consideration!


LTAs are long overdue in the USA :: The PTC was extended for 2013, but so what…

NB: The Production Tax Credit (PTC) is a tax break that enables wind farms to offset the cost of electricity production during the first 10 years of production.

GE just reported it is expecting a tough year in 2013 for its wind power business in the USA. While the production tax credit’s eleventh-hour extension improved the forecast for 2014, it came a little too late to help the company this year.

As a result of the low expectation on activity for 2013, Vestas is reducing its manufacturing footprint. Also,…

…it was cutting about 10 percent of its 1,100 manufacturing workforce in Colorado. It blamed the battle in Congress over a tax credit for wind generators.

Perhaps if the USA congress would cease manufacturing misinformation about renewable energy technologies, and provide the industry with long term agreements (LTAs), this industry could take off in a massive manner, post haste.

Berkeley Lab sees wind power as cost-effective, long-term hedge against gas prices

In the near term, the U.S. “dash for gas” is making it harder for wind power and other renewable energy technologies to compete on price alone, according to the report. But a comparison of existing wind power purchase agreements, which lock in rates that utilities pay, against scenarios that contemplate rising natural gas prices reveals that wind power continues to be a strong long-term bet.

If the politicos could only grasp and comprehend the longer term notion that wind power has a high degree of price stability, making wind energy a strong, long-term hedge against rising natural gas prices–which mind you, according to the Berkeley report, the price of natural gas is slated to start rising again as early as 2014.

But LTAs supporting production of renewables should not be the only focus. We need to enhance the electrical distribution network and implement more storage and smart(er) grid technologies to handle the intermittency of renewables for better load management. USA R&D jobs creation would also be a nice consideration, too.

Can I get an ‘Amen!’ for funding being earmarked for more R&D, so we can better deal with making this transition off fossil fuels more expediently?


An elegant solution for a problem during extreme weather events — small wind turbines

It’s just an idea. A great deal of small wind turbine generators can withstand  Category 1 hurricane wind speeds. [Citation: Saffir-Simpson hurricane scale]

There are, however, some small wind turbine generators installed on the Boston-Cambridge Museum of Science back in 2009 that have survival wind speeds of up to 155+mph (Category 4):

  • Mariah Power Windspire – survival wind speed – 105 mph | 47 m/s (Falls w/in the Category 2 range)
  • Cascade Engineering Swift – maximum designed wind speed – 145 mph | 64.8 m/s (Falls w/in the Category 4 range)
  • AeroVironment AVX1000 – designed to withstand 120 mph winds — good for low-aspect ratio structures (Falls w/in the Category 3 range)
  • The Proven 6 – cut-out wind speed –  >155 mph | >70 metres/second (Falls w/in the Category 4+ range)
  • Southwest Windpower SkyStream 3.7 – survival wind speed – 140 mph | 63 m/s  (Falls w/in the Category 4 range)

I wondered how they faired during Hurricane Sandy? Yes, I have made an enquiry and am awaiting a reply.

Hurricane Sandy caused some hospitals in NYC to evacuate patients, because their diesel gensets ran out of fuel. This should have NEVER happened if the hospital administrators planned better for contingencies.

Perhaps if they had had some properly designed and sited small wind turbines and PV arrays, er hybrid renewable energy systems, installed on the rooftops, coupled with back up batteries to capitalize on the indifferent forces of Mother Nature, there would not have been a need to relocate all those patients. Of course, I am not sure if this would be a pragmatic solution, since this is all contingent on the extent of the load requirements and if the wind turbines can withstand hurricane force wind. In general, I think generating electricity closer to where it will be used is a way to go, and smaller hybrid renewable energy systems is better–especially systems that can be deployed quickly and disassembled quickly.

I rather like one of my colleague’s designs, the AVX-1000, that is best sited on low aspect ratio buildings to capture the chimney effect of wind coming up the side of a building. When it’s not ‘hurricane season’ these stylish machines, should not draw as much ire from NIMBYs.

In a disaster scenario, I think implementing wind turbine generators (WTGs) is particularly elegant way to go–this turns a problem into a solution. Sure, perhaps in most locations in a city, small WTGs are not pragmatic because of all the roughness. This, however, could be the exact reason why small WTGs in the built environment can be added to the equation. When power is lost, wind is a direct or indirect cause, so there is plenty of energy for the taking, sun or no sun…

If I get a ‘moment’, or as soon as I can obtain all the pertinent data I require, I’ll post up a cost-comparison analysis of what it would cost to install a small, hybrid renewable energy system on these hospitals and compare this to a guestimated cost of what was spent to evacuate and relocate the ~1,000 patients from NYU Langone Medical Center and Bellevue Hospital Center during Hurricane Sandy. Ja, I’m a hope addict…


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What is a Hybrid RE Engineer?

An engineering generalist with an understanding of sustainable development whose skills set are typically comprised of an amalgam of mechanical and electrical engineering. One who is able to design and assemble systems and components that are comprised of more than one renewable energy (RE) technology i.e. solar, wind, hydro-kinetic (ocean/wave/micro-hydro), biomass, hydrogen fuel cell, geothermal and storage (battery, fly wheel, pumped-hydro). The RE technologies selected depend on one's geographical predisposition, resource availability, the end-use need, practicing conservation (behavioral change) to name a few considerations...

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