Den stora tråden om global uppvärmning/växthuseffekten

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Solpaneler är skit också. Bokstavligen! (video):

David Croom - (ツ)
@dailycallout

The manufacturing of solar panels leaves a trail of chemical pollution. And it turns out that the time it takes to compensate for the energy used and the greenhouse gases emitted in photovoltaic panel production makes it far less than “green”!

https://twitter.com/dailycallout/status/1358456993267150850?s=20

Comparison between the Energy Required for Production of PV Module and the Output Energy Througout the Product Life Time
«As the results show, if taken into account the energy used in the manufacture of a module (as quantified in literature), and the energy that a module system produces (as simulated), this technology proves to be self-sustainable. Because of having many years of clean energy production, even if in the first year, the system equals the energy spending in manufacturing, with gains in use.»

https://www.researchgate.net/profile/Lea_Dai-Pra/publication/282206521_Comparison_between_the_Energy_Required_f or_Production_of_PV_Module_and_the_Output_Energy_T hrougout_the_Product_Life_Time/links/5748d2c008ae2e0dd30168ab/Comparison-between-the-Energy-Required-for-Production-of-PV-Module-and-the-Output-Energy-Througout-t he-Product-Life-Time.pdf

/.../Estimates of the exact amount of rare earth minerals in wind turbines vary, but in any case the numbers are staggering. According to the Bulletin of Atomic Sciences, a 2 megawatt (MW) wind turbine contains about 800 pounds of neodymium and 130 pounds of dysprosium. The MIT study cited above estimates that a 2 MW wind turbine contains about 752 pounds of rare earth minerals.

To quantify this in terms of environmental damages, consider that mining one ton of rare earth minerals produces about one ton of radioactive waste, according to the Institute for the Analysis of Global Security. In 2012, the U.S. added a record 13,131 MW of wind generating capacity. That means that between 4.9 million pounds (using MIT’s estimate) and 6.1 million pounds (using the Bulletin of Atomic Science’s estimate) of rare earths were used in wind turbines installed in 2012. It also means that between 4.9 million and 6.1 million pounds of radioactive waste were created to make these wind turbines.

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Consequently, the growing popularity of permanent magnet generator leads to increasing demand of Nd. Based on Emsley’s (2011) statement, wind turbines armed with permanent magnets require 0.7-1 ton of neodymium alloy for every megawatt (MW) of capacity. And a single Scanwind 3500 DL wind turbine with a 3.5 MW capacity, produced by a Finnish company called The Switch, needs more than 2 tons (equal to approximately 0.6t/MW produced) of neodymium-based (Nd-Fe-B) permanent magnet material for manufacturing (Hatch, 2009). In order to achieve enough wind power based electricity supply for global from Wind, Water and Sunlight (WWS) system, an increase by a factor of more than 5 in annual neodymium world production would be needed, which is quite impossible to be realized for a long time even with new extraction along with recycling measures (Jacobson and Delucchi, 2011). Additionally, more constrains from political power and incentives resulting from environmental concerns will limit the expansion of supply in the future (Lifton, 2009).The U.S Department of Energy (DOE, 2011) conducted a criticality assessment of rare- earth metals and pointed out supply challenges for dysprosium, neodymium, terbium, and yttrium in terms of clean energy technologies. Rare- earths permanent magnets benefits larger turbines and slower turbine speeds with direct- driven arrangement. Both of these designs are regarded as main trends of wind power development.

Meanwhile, the conventional wind power plant can also cause growth in demand of neodymium apart from the direct- driven ones. Since permanent magnets are also capable of reducing weight and cost of conventional wind turbine construction. An example of neodymium usage is that it is able to reduce an amount of weight of 10 tons of steel in the V112–3.0 MW tower (Davidsson et al., 2012). Different from direct-driven gearless wind turbines in which the neodymium in the form of permanent magnet is irreplaceable, conventional turbines require much less neodymium or even can be free from it. But more and more conventional designs are implementing permanent magnets to increase the efficiency and reduce the weight. Thus, neodymium utilization in conventional wind turbines should not be neglected.

In fact, the criticality of neodymium along with other rare earth metals used in wind turbines manufacture is less mentioned in current discussion or assessment of wind power plant constructions. More generally discussed issues are environmental and social impacts caused by wind power plant construction. These impacts mainly include sound propagation (Pedersen and Halmstad, 2003), health disturbance (Colby et al., 2009), threats to wildlife (Kuvlesky et al., 2007), increasing demand in land, and so forth (Wizelius, 2006, p.127- 205).

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Nowadays, magnet- related applications are responsible for a share of around 20% in the global total volume of rare earth applications, while the share of value is about 37% (Schüler et al., 2011). An analysis of global in-use stocks (by application) of rare earths in 2007 demonstrates that the total Nd in-use stocks were 137, 000 tons, which shared approximately 31% of global total REE stocks. In the same year alone, 14,800 tons of Nd flew into use. The whole in- use stock of Nd resides largely in computer applications with an amount of 40,000 tons(29%), audio systems with 31,000 tons (22.6%), wind turbines manufactures with 18,000 tons (13%), and automobile related application also took up 13% with 18,000 tons of material (Du and Graedel, 2011). Similarly, in 2008, the total production of rare earth oxide reached 129,000 tons, and the neodymium oxide production accounts for 23,900 tons, taking up 18.5 % of the total production. Among neodymium applications, about 76 % was used for magnets, an equivalence to 18,200 tons. The rest was used for metallurgy apart from batteries (8 %), battery alloys (5 %), ceramics (3.5 %), glass additives (1.5 %), automobile catalytic converters ( 1 %), andother applications (4.7 %) (Goonan, 2011). As following, figure 8 demonstrates global REO end use status and possible substitutes options (UKERC, 2013), while figure 9 presents a closer look of neodymium application in 2010, based on the data provided by Peiró et al. (2013).

NdFeB magnets are a critical component for some models of the new generation wind-powered turbines. Two tons of rare earth magnets arerequired in the permanent magnet generator that goes on top of the turbine. “If the permanent magnet is two tons, then 28 percent of that, or 560 lbs, is neodymium.