Author: Francesco Miceli
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CBR value – road aggregate thickness correlation
After a long search I’ve finally found a direct correlation between CBR and gravel thickness for unpaved gravel roads. I’ve discovered that often wind farms are built in areas with a low (<5%) to very low CBR. Somehow empirically, we’ve started with a standard 20 cm layer of gravel. We’ve learned the hard way that…
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AASHTO green book equation in wind farms road design
I’ve been recently asked to justify the roadbed thickness for a wind farm I’ve designed. For several reasons (mainly because the majority of documents are redacted by non-civil engineers) the engineering companies supporting our customer ask for a written demonstration that the road design comply with the requirement of the famous AASTHO 1993 green book….
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Relevant parameters in wind farm production
After the connection of a Wind Farm to the grid several parameters are used to analyze the smooth operation of the installation. The more relevant are: Capacity Factor [latex size=”1″]CF=\left( \frac{E(kWh)}{P(kW) T(h)}\right )[/latex] Is a parameter used frequently in power producing plant. A high capacity factor means that the plant is working almost continuously (for…
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Narrow track cranes
In wind farms construction usually at least 2 cranes are needed: a main crane to lift component such as tower segments, blades and rotor and a smaller crane called “auxiliary” that help the main crane during the lift operations to manipulate the wind turbine component. The auxiliary crane can also be used to move steel…
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Nacelle Trailer (Low Loader)
Nacelle trailer (also called low loader) is one of the special vehicles currently used to carry WTG components from the factory to the wind farm. His peculiarity is that it’s very low, only a few centimetres above the road: this is to allow transportation on public road, where bridges with a free height of 5…
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Carrying blades with a balloon
In very complicated wind farms blades and sometimes other components are carried by helicopters – an expensive solution, to be used only as “last option”. What I’ve discovered today is that a balloon was used by CL CargoLifter to carry the blades in a small scale test made for Nordex at the former airport of…
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Wind turbines components transport problems
Transport related problems occupy a relevant percentage of time in my department. It’s no big surprise, considering that the models that we are selling (V90, V100 and V112) have blades up to 55 meters. Usually we have 3 different kinds of problems: Bending radius Vertical transition curves (for instance on top of hills) Weight…
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LEGO and Vestas: The unlikely duo
As you probably know if you are in the wind sector both LEGO and Vestas are Danish companies, so it is not a big surprise to discover that several wind turbines related products are produced by LEGO. Not only the “standard” LEGO City 7747 Wind Turbine Transporter, but even a personalized, limited edition set (known…
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Wind Farms construction contracts
Wind farms can generally be broken down into 2 separate areas of construction: Turbines: supply, installation and commissioning of wind turbines and towers Balance of Plant (BoP) works: everything else needed except the turbines (foundations, substations, cabling, etc.) Several option are available to the developers: The first option is that the wind farm Special Purpose…
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Medium Voltage Cables Optimization
The optimum design of the medium voltage (MV) cables consists in finding the best compromise between the initial cost of the cables and the total energy loss of the system. For this reason we design wind farms with a radial network, and section of the cables decreasing from substation to the most faraway point of…