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Small Scale Wind Turbine Energy Generation

March 16, 2013

In response to some of my prior articles and commentary critical of public/government support for wind turbine energy production on other sites and media, I have received questions and comments indicating that small scale turbine installations are superior to large scale wind farms.  While I am very much in favor of individual investments, responsibility, and decisions, and would love to find a small scale device that is effective and reliable; I have analyzed many small scale residential or commercial end-user wind turbine applications, and have found none that demonstrate any better performance than the large scale industrial wind-farm models.  The wind turbine projects all completely rely on subsidies and rebates from the taxpayers to make them even remotely feasible.

The underlying problem is a lack of energy density and reliability.  An excellent article entitled “No time to abandon energy density” by Professor Colin McInnes FREng recently appearing on Ingenia Online indicates the following:

“When James Watt’s separate steam condenser began to displace Thomas Newcomen’s early atmospheric engine, it did not require government targets or financial incentives to encourage the take-up of the technology. Watt’s idea succeeded simply because it took less than half as much coal to deliver the same quantity of mechanical work. Watt’s innovation was part of a long-term trend in energy production; it was part of a continuous move towards using fuels of greater energy density and so lower carbon intensity……….

Many forms of green energy are spatially diffuse and intermittent, making them inefficient and inherently expensive. Therein lies the need for feed-in tariffs and other support mechanisms. Green energy is set to grow, not because it is more productive, like Watt’s separate steam condenser, but because government mandates it and provides generous incentives. An energy transition that leads to more expensive, less efficient energy production is more a regression than a revolution.”

To demonstrate the problems associated with small scale wind turbines I can present two specific cases that I have analyzed.  Case 1 is the installation of two Bergey 10KW wind turbines in Lordstown, Ohio.  Case 2 is the installation of one Skystream 2.4 KW wind turbine by the Keller School District, in Fort Worth, Texas. 

CASE 1 – Lordstown, OH

 Please refer to the Lordstown Turbine Analysis

The village council of Lordstown, OH, installed two Bergey wind turbine at their administration building, despite analysis indicating that the energy generated within the life of the turbines would never pay back the initial cost of installation. Given the average annual wind speed at the site indicated by Ohio Siting Board wind maps, the energy output of one of the Bergey turbines can be expected to be 13,228 KWh. Factoring in the cost of electricity, inflation, and O&M costs (ref. “The Wind Energy Operations & Maintenance Report”  Feb. 2010); payback of originally published full investment of $131,700 for two wind turbines will never happen.  Over $40,000 will remain unpaid after 30 years. 

The economic analysis based on the published investment of $131,700; does not account for federal or state grants, amounting to approximately $118,000, which were received by Lordstown.  These taxpayer funded grants (“free money”) were the ONLY things that made this project viable and attractive to the Lordstown Village Council.

Latest Info Update:  Published information from last year indicates that the 2 wind turbines in Lordstown managed to produce a combined total of only 6,450 KWh in their first year of operation.  The situation is much worse than the analysis predicted.  The power curve information provided by the turbine manufacturer and/or the NREL wind map information may well be inaccurate.

CASE 2 – Keller School District Fort Worth, TX 

Please refer to the Keller Turbine Analysis

The Keller School District in Fort Worth, TX, recently installed a Skystream 3.7  2.4 KW wind turbine at one of their facilities.  The project expenditure was originally questioned in an article by Dave Lieber, a columnist for the Star Telegram.  Mr. Lieber was also quite helpful in providing information regarding the specific model of wind turbine, and in providing a Return on Investment (ROI) analysis provided by the Keller District itself.

Given the average annual wind speed at the site from referencing NREL Wind Maps for Texas,  the annual energy output from a Skystream 2.4 KW wind turbine can be expected to be approximately 3,012 KWh.  Factoring in the cost of electricity, inflation, and O&M costs (ref. “The Wind Energy Operations & Maintenance Report”  Feb. 2010); it is reasonable to expect that payback of the investment will take at least 26-28 years.  Further, based on the Operation & Maintenance Report (sited above) it is not reasonable to expect this many years of service from the wind turbine (20 years or less is a more reasonable expectation).  Therefore, no payback of the investment will occur within the life on the turbine.

Per the Keller School system “The reasoning for the installation of the wind turbine was to support instruction of the Gateway Technology program related to the specialized section on Energy and Environment.” The district indicates that the wind turbine was purchased for science and technology education purposes, not for ROI; and I can understand this perspective to a point.  My questions, however, would be:  Are the actual facts of the wind turbine performance, as demonstrated by this turbine, being presented to the students?  Are the ineffective and unreliable output, and the drawbacks of wind power generation, being presented; and are they honestly demonstrating to the students that wind turbines are NOT an effective answer to our main-stream general energy needs?

ADDITIONAL CONSIDERATIONS: 

  1. These economic analyses do not account for the cost that will be incurred to maintain and operate a traditional back-up system for generating power when the wind is not blowing adequately, and for the added cost and inefficiency of cycling this back-up system on and off to balance the supply load against the variability of the wind generated power.
  2. These analyses are presented for a 30 year period, although it is becoming evident that the useful life of many wind turbines is less than 20 years; and sometimes as little as 10 to 15 years.
  3. Any supposed reductions in dependency on conventional power generation and any reductions in associated levels of pollution, attributed to use of wind power generation, are highly suspect; because of the need to maintain and      operate the back-up systems in an inefficient manner.
  4. The lowest wind conditions and the lowest power output will occur in the summer, when the electricity demand is highest.
  5. Additional research indicates that the actual output of some small scale wind      turbines (including the 10KW Bergey units analyzed here) might be even      significantly less than the manufacturers are letting on.  Please refer to the Massachusetts Renewable Energy Trust (MRET) status report on small wind energy projects, found at http://www.cadmusgroup.com/pdfs/MRET.pdf  (Ooops the link broke.  Try this attacment:  MRET – Status Report)
  6. The money spent on wind turbines could be spent in a variety of other ways that are more effective at both producing consistent reliable electricity and reducing CO2 emissions and emissions of other real pollutants.

The point to take away from this information is not that electricity CANNOT be derived from the wind.  Obviously electrical energy can be generated from the wind, and in some cases individual point-of-use application of wind turbines may make sense (especially if energy storage technology is improved).  However, the inherently poor energy density & reliability and other drawbacks make wind turbine implementation a poor contribution to our main-stream energy strategy in general.  The analyses show that the currently available wind turbine devices, for both large scale and small scale applications, do not provide enough energy to pay for themselves, and are NOT effective at providing electricity with the energy density and reliability needed.  Further, the benefit that they are advertised to provide (i.e. pollution reduction) is highly suspect, because there will be an endless need to maintain and operate traditional power generation methods in an inefficient manner to back-up the unreliable and variable wind generation.

Because emotional and political, rather than rational, decisions are being made; huge amounts of taxpayer resources are expended pursuing implementation of wind turbine technology, when it is not ready for implementation.  Unfortunately, this wastes resources and money that could be better spent in other ways helping us to pursue other effective improvements to our energy strategy.  To quote again from Professor Colin McInnes:

“As the UK drives forward with an ambitious programme to deploy various forms of green energy, it is becoming clear that a combination of energy-dense, lower-carbon methane, partly from expanding reserves of shale gas in the UK and elsewhere, together with uranium, and later thorium, can be the key fuels of the future. This combination can provide the foundations of an energy policy to deliver future abundant, clean energy from compact power plants.

The era of cheap energy is over only if we choose so. If we use technical innovation to accelerate, rather than supplant, moves towards greater energy density, we can deliver energy that is both cheaper and more abundant. And, as a useful side effect, we will help de-carbonise our economy in the process.”

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2 Comments
  1. Gary Alligood permalink

    Jerry-
    “CCGT” in the context of power generation on the grid in the USA is an abbreviation for “Combined Cycle Gas Turbine.” Of course the steam cycle is in a closed loop, but that is not the same as a Closed Cycle Gas Turbine.

    I find your economic analysis simplistic but you are not far off the mark. Wind and solar power are more expensive in total costs than gas fired generation. Without tax incentives and renewable energy mandates, wind and solar cannot compete with other forms of generation, at least in terms of the costs we can see today.

    I generally support these technologies but people should understand the costs and reasons behind these investments.

    I applaud your efforts to bring the benefits and costs of these technologies to light.

  2. Gary,

    Thank you for reading and commenting.

    You are correct, I intended to refer to Combined Cycle Gas Turbine technology, and erred in referring to it as Closed Cycle Gas Turbine technology. I will make this correction in future articles.

    You are also correct that my economic analysis is simplistic. I realize that it is simplistic. The point to be taken from this is that it only requires a simplistic analysis to realize how poor the performance and business case of these wind turbine (and solar panel) projects are.

    In the real world, if the intial simplistic analysis indicates good performance (or even a close call) a more detailed analysis is warranted. But when the intial simplistic analysis indicates performance this poor, there is no need for a more detailed analysis. The projects I have analyzed do not pass an initial “sniff test”.

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