Archive for the ‘Professional’ Category

Sodar: Operation and Limitations (1/2)

February 18, 2012

On last post I explained briefly some features related to this Remote Sensing (RS) apparatus, but I consider that it should be explained further. Therefore, I am going to detail other considerations related to Sodar’s technology through two posts based on the academic paper of S. Bradley, I. Antoniou et al. (2005). By now, physical principles and uncertainties will be described. Next post will focus on its calibration methods.

Sodar is a Remote Sensing apparatus that measures 3D wind speeds at high altitudes. By emitting vertical sound beams of sound, it is possible to interpreter the backscattering frequencies due to the Doppler Effect and thus, wind components can be decoded (See Fig. 1). Usually, three or five beams are necessary to obtain reliable raw data measurements. Each of them is usually tilted 15-20º (ϕ) to the vertical (See Fig. 2). Though the emitted signal produces a continuous backscattering echo after crossing the infinite turbulent layers in the atmosphere, the echo generated at the studied altitude (Z) can be recognized according to the following formula. This means that among the continuous echo signal received, the specific signal generated at the Scattering Volume at Z height is generated at t (time) moment. The same principle is used by pulsed lidars.



Dow Company and their links with the Wind Industry.

July 26, 2010

It is interesting to discover how companies that they are not directly related to the Wind Power can work for this field as the typical companies do. An example of this, it is the American Chemical company Dow Chemical. This multinational, it is one of the largest companies on the Chemical field with DuPont or BASF.

Dow Chemical provides a wide range of plastics, chemicals and agricultural products with presence in more than 175 countries and employing more than 50.000 people worldwide. In the last year (2009), it reached 44.875 billion U.S dollars and 648 billion U.S. dollars.


Politics and Cap&Trade.

July 17, 2010

I have just found an article on Renewable Energy Focus website that explains which countries are interested on increase the target to reduce the greenhouses reduction for 2020. On one hand, we have countries (Spain, Germany, Sweden) which want to achieve the target of reduction to 30% below 1990 emissions. Others, like the UK, Portugal, Austria or France that want to keep the 20% approved in the past years. And finally, countries such as Italy, Denmark, and Belgium which their interests are different and they want to reduce that demanding target.

The position of each country must be directly related to the “Cap and Trade” regulatory system. This program allows to the manufacturers of gases linked to global warning to “trade” pollution permits, or allowances among themselves. It is important to point out that the European Union Emission Trading System is currently the largest functioning Cap and Trade system for greenhouse gases in the world (the permits generate an industry of $140 billion per year).


Gamesa Vs Acciona.

July 1, 2010

We saw on last posts that Gamesa and Acciona are the Spanish biggest companies in Wind Power. After reading their websites, we downloaded their General Ledger Accounts to analyze them.

These reports are so big (more than one hundred pages) that it doesn’t make sense to make a detailed analysis in this post. Furthermore, Gamesa’s later results published are from 2006 and the Acciona’s are from 2009. So, it is quite hard to compare them. Anyway, let’s see what we can discover.


Links & Sources.

June 27, 2010


Information usually has a very important role in our lives. If we could find the answer for our questions or queries in an efficient way we could accomplish easier our dreams. Internet has helped us very much and nowadays when we need to find new information our first idea is to use Search Engines such us Google or Yahoo.

However, it is very frequently when we are looking for something specific on Internet, we finish on worthless websites and forgetting what our purpose was. So, in order to make easier this task, we are going to show a list of websites that we can help us.