A wind turbine can pay for itself in less than a year

Originally posted by twhitehead
99.9% of the cost of microchip manufacture is energy? I doubt that.
References?

[b]2, Manufacture of steel from iron ore.
Smelting, I realize is very energy intensive. However, heat is not the only energy requirement. There is transportation, and crushing as well. And I am not convinced that enzymes would make as significant difference as you see ...[text shortened]... ock first, soak it in the enzyme -which would do what? Dissolve the iron in solution? What next?[/b]

99.9% of the cost of microchip manufacture is energy? I doubt that.
References?

I did a VERY long internet search and I couldn't get specific percentages so gave up BUT here is some indicators:
http://www.lowtechmagazine.com/2009/06/embodied-energy-of-digital-technology.html
“...The energy needed to manufacture microchips is disproportional to their size.
…
Manufacturing one kilogram of electronics or nanomaterials thus requires between 280 kilowatt-hours and 28 megawatt-hours of electricity...
…
Why are microchips so energy-intensive to manufacture? One of the reasons becomes clear when you literally zoom in on the technology. A microchip is small, but the amount of detail is fabulous. A microprocessor the size of a fingernail can now contain up to two billion transistors - each transistor less than 0.00007 millimetres wide. Magnify this circuit and it becomes a structure as complex as a sprawling metropolitan city.

The amount of materials embedded in the product might be small, but it takes a lot of processing (and thus machine energy use) to lay down a complex and detailed circuit like that. While the electricity requirements of machines used for semiconductor manufacturing are similar to those used for older processes like injection molding, the difference lies in the process rate: an injection molding machine can process up to 100 kilograms of material per hour, while semiconductor manufacturing machines only process materials in the order of grams or milligrams.
Another reason why digital technology is so energy-intensive to manufacture is the need for extremely effective air filters and air circulation systems (which is not included in the figures above). When you build infinitesimal structures like that, a speck of dust would destroy the circuit. For the same reason, the manufacture of microchips requires the purest silicon
Every 18 months the amount of transistors on a microchip doubles (Moore's law). On one hand, this means that less silicon is needed for a certain amount of processing power or memory. On the other hand, when transistors become smaller, you need even more effective air filtration and purer silicon. Since the structure also becomes more complex, you need more processing steps.

Nanotechnology operates on an even smaller scale than micro-electronics, but its energy requirements are comparable.
…”



-and not that one thing that enzymes in nature are very good at doing in nature is creating nono-scale and molecular-scale structures extremely fast and efficiently (example, the enzymes that can grow a whole microtubule within just a few seconds! ) and I see no insurmountable barrier preventing us eventually (possibly in the far future ) designing enzymes that can do the same thing! -can you?




http://www.atariarchives.org/deli/birthing_microchips.php
“...
Ion implanters are used to "dope" layers with impurities by shooting molecules at the surface under high vacuum conditions. Diffusion furnaces coat molecules onto the surface of the wafer using violent chemicals and natural molecular affinities at temperatures exceeding 1,500 degrees Fahrenheit. Furnaces can also remove selected molecules in a bath of hot oxygen. Silicon itself is layered by epitaxy

The combinations and protocols are myriad in this painstaking layer-by-layer fabrication process. It can take as many as six weeks to fabricate a microchip. Each step of the recipe requires handling, and some steps-particularly in the diffusion furnaces-require many hours while molecules attach to molecules according to nature's inexorable laws.
...”


note what the above says about the use of furnaces. Furnaces generally guzzle one hell a lot of energy! SURELY, given the above indicators, it is reasonable to expect that something like ~99% of the cost of manufacturing a microchip is in energy costs?
How do you think that the cost of, say, the chemical element silicon, which typically makes up the bulk of the microchip, costs compared to the raw material costs? Dirt cheap sand contains silicon! Of course, to extract that silicon from sand using conventional techniques requires a lot of energy! But the silicon itself costs virtually nothing in comparison because it is just so common!
OK, obviously the microchip also contains some not-so-common elements such as copper -but surely, given that most of it (by volume ) is usually silicon and given the relatively small amounts of copper used, surely copper would only take up a small proportion of that cost? If you take the same volume of pure copper as in a microchip but not in a microchip but just have it as a chunk of copper by itself, how much do you think it would cost compared to how much the whole microchip costs? -and that is ignoring the fact that much of the cost that goes into obtaining pure copper is energy costs!

Smelting, I realize is very energy intensive. However, heat is not the only energy requirement. There is transportation, and crushing as well.

OK, I was wrong about steel, I assumed that transportation and crushing would be dwarfed by the energy consumption of all those massive energy guzzling furnaces that melt it and process it at temperature so high that it is white hot!

Again, I did an internet search to try and get relevant figurers but, to my surprise, found an indication of the exact opposite of what I assumed:

http://ec.europa.eu/enterprise/sectors/metals-minerals/files/steel-cum-cost-imp_en.pdf
“...an plants shows that raw materials account for 63% of total costs and
energy for 13%. Likewise, expenditures for raw material are equal to 62% of overall
production costs in Central Eastern European facilities, while costs for energy reach up
to 14%..”

Just 14% ! I honestly thought it would be more like 99% ! furnaces guzzle one hell a lot of energy! Mind you, I would imagine that, in the far future, steel will rarely be used because there are materials that are superior to steel in every way for most applications and the manufacturing costs of the alternatives is bound to go down substantially as a result of advances in manufacturing technology.

What next?

That depends but the enzyme could be designed to chemically combine the iron from the iron salt to another chemical compound that could be grown on a surface to grow some kind of solid ceramic material -a bit like how bone grows in nature.