Wind Measurement Limitations Explained with a Spinning Bucket Analogy

Visualize a bucket filled with water half the way to facilitate mixing, covered with a lid.  Now, imagine this bucket spin out of control, jump, wobble, momentarily stop, and randomly resume any of these actions.  Begin drawing a drop of water from a location within this bucket and measure its properties such as its speed.  Put the water drop back and wait for ten minutes and draw another drop from the same exact location as before and measure its speed.  Keep repeating this measurement effort for a while.  Now, use these measurements to characterize the chaotic behavior of the entire fluid (water) in the bucket…click here to read the rest of the article.

Visit http://www.linkedin.con/in/resprincfounder to learn more about the author, Dr. James Stalker.

What are “wind forces” and why one needs to worry about them?

I just returned from a two-day workshop on wind resource assessment. The global wind energy community does not seem to be ready to face the difficult challenges posed by wind. In this context, the wind energy community should go beyond the current practices of just wanting to measure wind. Afterall, wind is the net effect and the wind forces are the underlying causes. Should one just ingore all the causes and expect to do well by focusing on the effect alone? Unfortunately, that is exactly what the wind industry has been doing, i.e., focusing on the effect, so far.

This discussion elaborates on what is beyond our current horizon (wind forces) and why these forces are paramount to the global wind energy community’s successful deployment of wind projects.

Wind resource assessment is just one of many pieces of the wind project development puzzle. However, it is understandably one of the most important aspects of wind project development.

As mentioned above, the global wind energy community has focused on measuring wind at potential wind sites. It is from this type of wind information, other energy and financial analyses are made to ascertain wind project viability.

Unless one is developing a single-turbine wind project with the measurement height matching the hub height, has enough time to measure (a year or longer), and has the appetite to assume significant risk involved in long-term energy projections, wind measurements made at a location for a year are limiting.

The above limitations do not result from any inaccuracies of the measurements…click here to read the rest of the article.

You can read more about the author at http://www.linkedin.com/in/resprincfounder.

The Future of Wind Energy Assessment

Successful wind energy assessment efforts require adequately established long-term (> 20 years) wind behavior at potential wind project sites. Measurements, from such traditional instruments as anemometers or from more advanced measurement platforms such as sodars or lidars will not help overcome the issue related to the time requirement for long-term wind energy analysis. Additionally, measurement platforms, both traditional and advanced, will only provide data at limited locations and heights. This spatial coverage limitation may prove to be a significant issue for wind farm sites within complex terrain locations.

When clearly known wind farm energy performance variability is of utmost importance for wind project developers and financiers alike, limited wind measurements in space and time are proven to be inadequate, expensive, and time consuming.

Fortunately, there is a cost-effective and timely alternative.  An example of such an alternative is based on an Atmospheric Simulation Technology, developed by Dr. James Stalker. This simulation technology offers location specific, height specific, and time specific wind information, not only at a much lower cost but also within a fraction of the time. For example, the 100-m height wind information can be obtained for only a few 10’s of thousands of dollars compared to much more expensive measurement efforts.  Also, yearlong assessments can be completed within weeks.

As important as the above two advantages are for simulation based wind energy assessments, the greatest benefit is in their ability to provide comprehensive spatial information within weeks. In other words, project developers do not have to rely on measurements made at a single location or use just one year measured data to determine long-term wind energy variability. In other words, wind project developers and financiers need to ask themselves this question: “Would we not measure wind for twenty years at every possible location within a prospective site if we had all the money and time in the world?” The answer would be a resounding ‘yes.’ And yet, these folks are currently relying…click here for the full article.

Dr. James Stalker writes on science and technology topics and topics related to his high-tech businesses.  For wind energy assessment, please visit www.wind-energy-assessment.com.  For renewable energy consulting services, visit www.renewable-energy-consulting-services.com.

The Difficulty in Quantifying the Extent of Global Warming or Cooling

I mentioned about the difficulty in understanding and quantifying future atmospheric states in one of my previous blogs (see http://jrstalker.wordpress.com ).  This blog elaborates on that difficulty with examples.

Most of us, earth system and atmospheric scientists, other scientists and engineers, and non-scientists of all other disciplines, can easily grasp the concept that the coupled Earth system is extremely complex to understand in its entirety and accurately quantify its future states, even on short time horizons. For example, our ability to accurately predict future atmospheric states is limited to two to three days at best.  And yet, scientists have always tried to forecast future states on much longer time scales such as annual, decadal, and millennial scales.  What is the basis for such claimed ability to predict future atmospheric states on much longer time scales accurately?  It is all based on our presumed ability to separate scales, both spatially and temporally, and treat some of those scales independently of the others to perform predictive projections of future atmospheric states.  This ‘separation of scales’ certainly helps overcome the inherent difficulty noted here in accurately predicting the coupled solar-earth system but it does not actually help us solve the underlying problem that we face.

In the old days of not too long ago when sparse observations were not uncommon and limited computational resources were a norm, such unsupportable scale separation was not only encouraged but was perhaps the only and most effective approach that could be employed.  We have made tremendous strides on those two fronts, i.e., the density of observations has increased significantly, just as the available computational resource.  Unfortunately, though, our legacy approach based on scale separation lives on.  Unless we vehemently question this fundamentally flawed premise…click here to read the full article!

Please visit www.linkedin.com/in/resprincfounder to learn more about the author, Dr. James Stalker.

What is often lost in the global warming debate?

I had recently written on the ongoing global warming debate and why there are quite a number of scientists out there that are skeptical about global warming or cooling.  It is not that these scientists believe that there is no anthropogenic influence on climate change.  It is not even that these scientists believe man-made influence is infinitesimally small.  It is rather that these scientists believe that we have not adequately developed the tools necessary yet to collect sufficient data and build process representative numerical models to quantitatively differentiate a number of simultaneous influences on climate change.  [The difficulty in simultaneously capturing such process-related influences on the earth system and why we often fail to quantify these influences in our efforts will be discussed in a forthcoming blog.]

Global warming supporters claim that these anthropogenic influences are detrimental to the planet’s very survival, while those that vehemently oppose global warming want everyone to believe that there is nothing wrong with the climate as a matter fact.  The supporters have managed to show horrific scenarios of disappearing glaciers, wild life, etc. to make their case.  The opponents, on the other hand, often state that global temperatures have always gone up and down for the longest time and the sun’s radiation output reaching the earth has had a lot to do with such natural earth temperature variability.  Obviously, it does not take a whole lot of inspection into the debate to ascertain the fact that there is ample confusion here and that confusion is precisely due to our lack of understanding of the solar-earth system.

In the midst of this heated debate and the above mentioned confusion, one critical aspect is often overlooked.  The aspect pointed out here is about how willing we are to ignore our polluting ways to support our life styles and maintain our standards of living.  Even if all of the pollution we introduce into the earth system is categorically proven to make no difference in the natural climate states, we should recognize our irresponsibility here and curb our pollution.

There is a concern, however, that such a drastic change, in our ways of living, being proposed here may lead to economic hardships and loss of standards of living for some people.  This is a real concern and should be addressed rather carefully.  In this regard, sensible policies should be made to pragmatically transition our ways of producing energy to much cleaner ways, without affecting standards of living.   We all should improve our ability to tackle the overall difficulty in measuring and in simulating the earth system and always strive for cleaner ways of energy production and accomplish all of these daunting tasks responsibly, with or without global warming/cooling. 

The bottom line is that we should not bury our pollution in the global warming debate and pollution is what seems to be lost in the current debate!

Dr. James R. Stalker is an atmospheric scientist, a mechanical engineer, an entrepreneur, and an inventor.  You can learn more about Dr. James R. Stalker at www.respr.com or www.renewable-project-consulting.com.

On the Global Warming Debate

As most people are aware of the fact that there is ongoing heated debate among those who support gloabal warming and those who oppose it.  There is quite another group of scientists that belongs to neither category, simply because they believe there is not enough corroborating evidence to back up the theories in one way or another.  I am one of those scientists that are skeptical about our current abilities to understand the complex and coupled earth system adequately.  In this context, I strongly recommend we undertake focused and substantial research efforts.  As the scope of this issue is global and the implications and potential benefits are for all nations of the world, participation from all countries is vital.

Numerical models used to project future climate scenarios are no doubt evolving but are inadequate, at this time, for the purposes of capturing all energy related processes globally.  The observations, from temperature sensors, proxy records (e.g., ice cores), etc., used to support any argument are limited, laden with potential data quality issues, and often representative of only local to regional scale variability.  In other words, this approach often requires a quantum leap of  faith in order to be able to tie local variability to global climate states.

I fully support the debate, though, as it can potentially bring forth concensus among the participants and I sincerely hope that that concensus would point to the much needed research into the highly complex (solar-) earth system. 

Please visit www.respr.com to learn more about the author.