Author: Francesco Miceli
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Environmental impacts of wind farms
When I talk about my job with people coming from different businesses I receive often question linked to the “environmental impact” of wind turbines. This term include various effect related to the construction of a wind farm. They can be summarized in the following categories: Visual impact Are wind turbines ugly or not? This is…
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Key milestones in wind farm development
The development of a wind farm project is characterized by several milestones linked to contractual obligations of the parties. The most relevant milestones are marked below. They are in chronological order, and some of them could not appear in a specific project (for instance, not all projects have a limited notice to proceed or the…
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Strength in Numbers: the multi rotor, 12 blades turbine concept
The idea is not new: for instance around 1800 some “twin” mills have been used to pump water in Denmark and there are quite a few similar concepts and international patents dating the first half of 1900 – see for instance the drawing below. What is interesting here is the size of the company testing…
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Characteristics of wind turbine blades
The most elegant element of the wind turbine is, at least for me, the blade. Blades are currently reaching incredible lengths (onshore we are almost at 70 meters, offshore they can be even bigger) and, as I discussed in this post, can be made of several materials. The cheap solution is fibreglass, more heavy, while…
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The gentle art of EPC wind farms: design responsibility
In the ideal FIDIC world there is little space for the discussion about design responsibility. Either the Employer (FIDIC Red) or the Contractor (FIDIC yellow & silver) is going to do all (or almost all) the design. Unsurprisingly, real life is more complicate than this. You will have an hard time trying to get reasonable…
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Gearbox in wind turbines
Why do you need a gearbox in a wind turbine? The short answer is that you don’t need one – if you are using a direct drive WTG. But even if the solution without gearbox is used by several manufacturers (e.g. the Goldwind 2.5 PMDD, Enercon models, etc.) the majority of makers decided to include…
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Wind farm earthing and optical fiber cables
In this post of many, many years ago I explained how wind farm trenches are usually built. In addition to the medium voltage cables, in the trenches usually there are also 2 other type of cables: Earthing cables Optical fiber cables The earthing cables are usually made of copper and they are used to dissipate…
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Wind derivatives: is hedging the risk the next step for wind energy?
Weather derivatives are not a new product. The first contract were traded over the counter in the ‘90s, with the Chicago Mercantile Exchange (CME) introducing from 1999 a broad set of products like futures and options that are widely traded today. They are a financial product that can help hedging the risk associated with the…
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Constraints to medium voltage power cables in wind farms
(This post has been updated in July 2020 with the help of my friend and colleague Kamran) I already discussed in two other posts how the wind farm cable trenches are usually built and how the medium voltage cables are made. However, a more comprehensive explanation should include on how the medium voltage cables are dimensioned. The power produced…
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How to measure wind resource
I have to start with a disclaimer – I’m not a specialist in wind resource analysis. However, through the year I’ve seen several time this process so I think I can summarize it with a reasonable level of accuracy (and obviously if you spot a mistake, please let me know). The wind resource assessment is…