Showing posts with label digital fabricators. Show all posts
Showing posts with label digital fabricators. Show all posts

Saturday, December 19, 2009

Digital Fabbers, Resilient Communities and The Flow Of Stuff

Here's the next installment of my study of digital fabbers and their role in building communities that are resilient in the face of resource constraints and economic contraction. My interest in this subject is not merely academic. Rather, I am confronting this study as a man who realizes that the world has become a very messed-up place, and that the country I live in has become a particularly messed-up nation. I consider these issues in much the same way that a man's interest in aerodynamic principles might be sharpened by being in a seat on a turboprop flying through an ice storm.

When people are in trouble, it is only natural for their attention to be focused on evaluating potential solutions to their trouble. The world in general, and the United States in particular, face a number of very severe predicaments caused by the end of a cheap resource base for our industrial economy, the destruction of the environment due to that economy, and the resulting contraction and disintegration of that economy. Yet our leaders (and many of the common citizens) are proceeding cluelessly into the future, lost in wish-fulfillment fantasies. I see what's coming, and I want to make my passage through the coming trouble as easy as possible.

So I'm looking at John Robb's concept of “resilient communities” and the prominent role played by continually advancing technology (especially the digital fabber) in these communities, and I've been wondering, “can these concepts save me and my community from some serious trouble?”

In previous posts on this blog, we considered small, home-made digital fabbers (microprocessor-controlled automatic fabricators of machined parts) as a means of jump-starting small-scale manufacturing in the United States, a country which over the last several decades has outsourced the majority of its manufacturing to low-wage countries, and which is now heavily dependent on imports. The most laid-back promoters of digital fabbers point out their potential to empower local communities to make for themselves the goods on which they rely, without having to depend on regional or international trade networks. This is a benefit, as declining energy supplies and economic contraction will likely cripple large-scale or global trade networks.

The more enthusiastic promoters of digital fabbers tout them as a key step along the path to “superempowerment” of individuals and small groups. Digital fabbers enable small groups or individuals to make most or all of the things that are now provided by large corporations or governments. This democratization of manufacture is very similar to the democratization of the creation of artistic media (movies, songs, recordings, published writings) which occurred because of advances in microelectronics and digital communication.

According to some of the sources Robb quotes, the technologies with potential to drive the advance of resilient communities do not have fundamental constraints such as energy use that limit progress. This is because they achieve the expansion of their capabilities by miniaturizing functions, thus enabling more to be done in a smaller space with fewer resources. (Microelectronics are a prime example of this, with the size of discrete transistors, diodes, etc., shrinking all the time, so that the number of components that can fit on a chip increases exponentially as time passes – “Moore's Law” in action.)

Robb has speculated that this miniaturization might also be applicable to non-electronic systems – in particular, social systems organized on the community level might evolve to foster an exponential increase in wealth creation for the members of such communities. Such social system improvement would be enabled by, and dependent on, the continued availability of cheap, highly capable microelectronics and digital communication. (For instance, see “RESILIENT COMMUNITY: Fabrication Networks.”) These communities would be able to “enjoy the benefits of globalization without being vulnerable to its excesses.”

Can technology-driven “resilient communities” such as those envisioned by Robb deliver on such promises? I don't have a definitive answer. But I do have a few cautionary observations. First, I question the digital fabbers that would form the backbone of relocalized manufacture. We have already seen that they cannot yet make their own microelectronics. We have also seen that the making of silicon-based microelectronics is very energy intensive. Organic electronics don't require nearly as much energy to make, but they also don't perform nearly as well as silicon-based devices, and they require the use of exotic materials like nanotubes in order to boost their performance to levels approaching that of devices made of ultrapure silicon. The exotic additives to organic electronics also have high energy costs and require manufacturing facilities almost as elaborate as those used to make silicon devices. This means that even communities that had local small-scale fabricators would still depend on large-scale, centralized manufacturing facilities for some of the goods used by them.

But let's say that we were able to make digital fabbers that could make nearly anything, and could fit in the average suburban garage (right next to the washing machine and just behind that exercise machine you no longer use). We are immediately faced with a second question: where do we get the feedstocks used by the fabbers to make their goods? For instance, let's say I want to fabricate steel tubing for use in bicycle frames. I need a source of steel for the fabber to work on. Who will provide the steel? Or the plastic for fabbed plastic parts? Or the other feedstocks? What if some of these feedstocks require large amounts of concentrated energy for their production? If I want to make things out of aluminum castings, for instance, I must realize that producing raw aluminum as a feedstock requires large amounts of energy in mining bauxite ore, and in separating the aluminum in that ore from the other components. Then someone must deliver the finished aluminum to me. In a future of declining energy, how much raw material and what kinds of raw material will be available even for local manufacturers (let alone the big guys) to turn into finished products?

Next, how do local communities who possess their own means of production prevent the draining of wealth from themselves? It's fine to talk about relocalization as a means of keeping wealth within local communities. But we must realize that this is a reasonable goal only if the primary factor in the flow of wealth is the choice of the members of the community in spending that wealth. Now, however, we are seeing that the flow of wealth within communities and between communities and the larger world is no longer within the control of the members of those communities. Relocalization was a defensive response by communities to the sucking of wealth out of those communities by the super rich who were far removed from these communities. But the goals of relocalization have been overruled by the super-rich, who have enlisted the government as a tool to continue siphoning wealth from communities in order to concentrate that wealth within their own hands.

There are two obvious examples of this: the continued bailouts of the financial sector by the U.S. government, approved by politicians from both parties over the objections of their constituents; and the proposed “health care reform” legislation in Washington which would force all Americans to buy private health insurance. As the fortunes of the rich are threatened by the contraction of the global economy, they will increasingly use the government as a tool to extract wealth from the rest of us. This will mean the passage of laws designed to force ordinary members of ordinary communities to continue paying arbitrary “rents” of one form or another to the rich. As long as this happens, no community can achieve “resilience,” if resilience is defined by enjoyment and possession of material wealth in a technology-driven community.

I guess my main issue with John Robb's vision is that sooner or later, technology runs up against limits. Our limits are arriving fairly quickly. Soon we will not have access to large quantities of highly refined, specialized feedstocks for high-tech goods. A declining energy supply, combined with the exhaustion of available ores and other materials, will lead to scarcity of these things. I think that communities that are resilient (in the way I am now thinking of resilience) will be made of people who know how to reuse, how to hack things that already exist, and who are wise enough not to need or want shiny new stuff all the time. Such communities will be able to exist in the absence of globalism, which is a good thing, since I don't think anyone will be enjoying the benefits of globalism for much longer.

What might a different flavor of community resilience look like? In a future blog post, I might just give you a small picture of that. Meanwhile, though I don't think Mr. Robb even knows I exist, I hope he reads my little series of ruminations on his ideas. It would be interesting to hear his answers to some of my questions.

Sunday, December 13, 2009

Small-Scale Manufacturing and Digital Fabbers - Organic and Printable Electronics

This post continues our evaluation of the use of small digitally-controlled “fabbers” for small-scale manufacturing as a response to energy decline and economic collapse. Digital fabbers are a key part of the strategy which thinkers such as John Robb have for creating “resilient communities” that can weather the changes wrought by globalism and the hollowing-out of nation states by criminals, “terrorists,” and the extremely rich. (Mr. Robb's vision for resilient communities is driven primarily by the continued availability of cheap, advanced electronic technology. For an example of this, see Global Guerrillas: RESILIENT COMMUNITY: Technological Acceleration.)

I have only limited time for a post this week. Therefore I will give a brief summary of the things I've found relating to a vital component of digital fabbers: the microelectronics that control them. An advanced industrial society that depends on the localized, decentralized manufacture of the things it needs must be able to produce most or all of its necessary goods in this way. This applies to its electronic and microelectronic devices as well. In the last couple of posts, we have examined inorganic, silicon-based microelectronics manufactured in the ways currently employed in commercial industry.

This has revealed that the conventional manufacture of conventional silicon-based microelectronics uses large amounts of energy and costly equipment. The energy and equipment are necessary in order to produce the ultrapure silicon compounds that comprise the nanocomponents contained in most chips. According to a paper by Nestor Gonzalez Brasero of the Fundacion Telefonica, it takes 1.6 kg of fossil fuel, 72 grams of chemicals and 32 liters of water to produce a 32Mb DRAM chip whose final weight is only two grams. In 2005, 81 million desktop computers were manufactured in China, at an energy cost of 54 terawatt-hours.

It seems reasonable to assume that our expectation of the increasing availability of ever more advanced and cheap silicon-based microelectronics will one day hit a dead end. This is especially true for silicon-based components made in the standard way. Thus there has been a great deal of interest in the promise of electronics that can be made from organic compounds or other materials that don't require the high energy inputs and large-scale manufacturing plants needed to make ultrapure silicon wafers. From the turn of the 21st century various industry groups, researchers and labs have announced their interest in creating electronics, usually using inexpensive organic semiconducting compounds, that can be built by simple ink-jet printing onto a plastic substrate.

My digging around the Web has turned up the following facts:

  • The semiconducting property of certain organic chemicals has been known since at least the 1970's. In fact, melanin, a component of dark or tanned skin, is itself a natural organic semiconductor with some surprising switching properties.

  • Organic semiconductor electronics are now being used in some flat-panel displays. (The Pioneer Corporation has been producing a car stereo with an organic electronic display since 2001.)

  • Organic semiconductor electronics are being studied for use in printable RFID tags.

  • Organic semiconductor electronics are nowhere near fast enough to compete with crystalline silicon electronics at present. This is because charge transport velocities in organic semiconductors are orders of magnitude slower than in many silicon-based components. Their low charge transport velocity translates into switching speeds much lower than conventional silicon microelectronics.

  • Organic electronics require airtight protective coatings without which their performance degrades rapidly. In any case, their actual useful lifetime is limited to just a few years, and they will degrade whether they are used or not.

  • In order to create printable microelectronics with speed and performance comparable to conventional silicon-based chips, researchers are having to augment their organic electronics with metal atoms or to resort to the use of exotic materials, such as carbon nanotubes or silicon nanofibers. This detracts from the initial promise of low cost and easy fabrication of organic electronics. The making of these exotic materials still requires the same sort of high-energy, large-scale manufacturing plants that are now typical of silicon-based microelectronics. In addition, manufacturing of industrial-grade carbon nanotubes creates some serious potential pollutants.

I don't have a good handle on the energy cost involved in making organic electronics, as the technology is still in its infancy and many companies now doing research aren't interested in divulging their secrets. But I do have a couple of hunches. First, I suspect that printable and organic electronics are not yet ready to lead some next-generation “digital revolution.” Secondly, I think that large-scale, energy-intensive centralized manufacturing will still be required for many years in order to produce the fast, high-performance electronics of the sort that could power decentralized, localized manufacture of high-tech components and systems. This is a natural consequence of the need to use a lot of energy to turn high-entropy, highly disordered materials into materials with a high degree of order on a submicroscopic scale.

In short, I expect that the widespread manufacture of microelectronics will continue to remain an energy, resource and capital intensive process, although cheap, low-energy alternatives will be preferred for devices that don't have to be especially fast. It is here that printable and organic electronics can make a difference, as long as their users don't expect too much. Because of the requirement for energy and resources, I think the availability of cheap and powerful silicon-based electronics will decline as time passes. Devices based on silicon microelectronics will get more expensive. (And even if we ignore the probability of global energy decline, I think there's still "a ways to go" before you 'll be able to “print” a laptop in your garage using your own handy-dandy digital fabber ;) )

There's more to say, but I'm out of time. (Gotta get away from this computer screen!) I'm including a bunch of links below, for anyone who wants to dive in to this subject further. Enjoy.

For Further Reading

Sunday, November 29, 2009

Small-Scale Manufacturing and Digital Fabbers - The Question of Electronics

One of the consequences of the decline of available fossil-fuel energy is the contraction of our large-scale, global industrial economy. The decline in supplies of fossil fuels will make globalism prohibitively expensive as time goes on, due to the ever-increasing energy cost of shipping bulk-manufactured goods thousands of miles from their point of manufacture to their point of final sale. Many elements of modern society will therefore only survive via the revival of local, small-scale manufacture of goods.

The creation of small-scale, do-it-yourself digital fabricators (referred to from here on as “fabbers”), has been promoted as a key to the revival of modern-day small-scale manufacturing. According to many fabber proponents and enthusiasts, the rise of fabbers promises to do for manufacturing what inexpensive consumer entertainment electronics did for the creation of media. Whereas cheap consumer electronics enabled everyone to be a potential creator of art, education or entertainment, fabbers might enable everyone to be a potential creator of useful manufactured goods.

But for fabbers to serve as a true long-term solution to the breakdown of centralized industrial production, they must be able to create everything needed for sustainable localized economies – including parts to make more fabbers. To the extent that the making of fabbers requires parts or components that can only be made by large-scale plants in today's economy, to that extent fabbers are not really sustainable. One item of concern is thus the microelectronic components used to control fabbers, as these microelectronic controllers are now made in large, energy-intensive semiconductor chip plants. There are many issues of concern for those who want to try making microprocessors on a small scale, such as the very demanding and exacting conditions required for manufacture (vacuum chambers, ultrapure materials and clean rooms), and the energy required to achieve these conditions.

These conditions apply to all semiconductor-based microelectronics, though their impact varies depending on whether we are considering organic or inorganic semiconductor materials. Today's post will consider manufacture of inorganic semiconductor microelectronics. In this post, I do not promise to come to definite conclusions, but rather to raise important questions. It seems to me that these questions are too often not addressed by those who enthusiastically promote a “fabber revolution” as a solution to economic collapse. My posts on this topic are designed to provoke a conversation on this subject. There are four questions which I'd like to see addressed:

The Question of Energy

Almost all semiconductors in use at present are inorganic. (Liquid-crystal displays, some flat-panel screens and some RFID tags are notable exceptions.) Most inorganic semiconductor electronics are silicon-based.

In its natural form, silicon is literally dirt-cheap. However, the silicon found in sand and dirt is not nearly pure enough for use in high-speed electronics. The process of purification is not nearly as cheap. Metallurgical grade silicon (98 percent pure and above) is created by the reaction of high purity silica with other materials in an electric arc furnace heated to over 1900 degrees C. A method also exists for extracting pure silicon (purity greater than 99 percent) from silica by molten salt electrolysis. But this process also requires high temperatures (around 900 degrees C).

Electronic-grade silicon must be millions of times purer than 99 percent pure. The processes of this purification start with the aforementioned metallurgical grade silicon as a feedstock. They are all very energy-intensive, with the Siemens process (Chemical Vapor Deposition) having the highest energy requirement. Getting from beach sand to electronic-grade silicon is not cheap!

Once the silicon is at the right purity, it must be doped with trace elements in order to produce the desired semiconducting properties. This process is also energy and equipment-intensive, and requires a vacuum chamber containing pure silicon rods heated to 1000 degrees C. Many of the dopant chemicals are extremely poisonous, and some are also explosive.

Once the properly doped silicon has been created, it is cut into wafers which are etched and deposited with other dopants and contact metals in vacuum chambers in order to make the final microelectronic chips used in almost all modern digital devices. The processes of this manufacture are all quite expensive, both in labor, capital (machinery required) and energy. Modern digital devices are as cheap as they are simply because not much semiconductor material is needed anymore in order to make chips of great computational power. Yet energy is generally becoming more expensive as time passes, and shortages of dopant materials are also beginning to appear.

The Question of Dopants (And Other Exotic Materials)

The dopants used to alter the conducting properties of silicon and other semiconductors are themselves hard to find, hard to mine and relatively scarce in many cases. Antimony is one such dopant, used for both silicon and germanium semiconductors, and it has found extensive use in newly developed rewritable memory for digital devices. Most of the remaining antimony in the world is produced by China, and there is no U.S. domestic antimony production. Gallium is another material whose manufacturing users experienced a recent shortage, as was the case with indium also. Thallium is yet another metal whose supply has become constrained at nearly the same time that demand for the metal has increased. Many dopants and other industrial metals have witnessed Hubbert production peaks and are now in decline.

It may be that the electronics industry will experience a dead end in the use of certain elements within the next few decades, as the available supplies of these elements run out. This will mean a stop to the making of microelectronics that depend on these elements for doping. If continued advances in electronics are to continue, the industry will have to find alternatives to expensively produced inorganic semiconductors doped with scarce materials.

Hope On The Horizon? (The Promise of Exotic Materials)

Within the last few years, there have been exciting announcements of the discovery of exotic forms of common materials, forms whose properties hold the possibility of creating wonder microelectronics which don't need exotic dopants. One such development is the creation of silicon nanotubes, which have recently been fabricated into dopant-free nanotransistors by crossing the nanowires over each other and adding tiny metal contacts known as “Schottky contacts.”

However, the creation of these exotic nanowires requires a correspondingly exotic process. The first step is the production of silane from metallurgical grade silicon at a temperature exceeding 300 degrees C. The resulting silane is pyrophoric and explosive, and must be carefully handled. Then the silane is passed over a metal catalyst in a special chamber heated to at least 400 degrees C. This step is what produces the silicon nanowires. While the process can yield nano-transistors and other nano-components that do not require dopants, the process itself is still quite energy-intensive. One publication states that the silicon nanowire breakthrough may lead to “printable electronics” that can be produced by an inkjet printer. I myself am a bit skeptical. If someone could kindly explain to me how this would work, I would happily listen.

Concluding Questions:

The promoters of one particular fabber project state that their concept is the key to “wealth without money,” and that a society supplied by fabbers can “create wealth with a minimal need for industrial manufacturing.” They even talk of a society that is able to provide its own stocks of raw materials by turning crops into polymer feedstocks for fabrication by their fabbers, so that a cycle of wealth could be perpetuated (while reducing greenhouse gas emissions at the same time – a neat bargain!).

I remain unconvinced (but not dogmatically so). I think that, at least as far as energy and the resource-intensive microelectronics needed to run these fabbers, their promoters have overlooked the effects of looming scarcity, and the difficulties posed by the breakdown of our present industrial society. Has anyone made a do-it-yourself garage fabber that can make silicon nanowires? How about a DIY garage fabber that can even make metallic silicon? Are there fabbers that can make high-quality vacuum deposition chambers? Are there fabbers that can dope pure silicon without the risk of toxic gases leaking out and poisoning a few households in a neighborhood? Has anyone rigorously addressed the problem of obtaining large supplies of metallic silicon in an energy-constrained future? (This is the BIG question.) Most importantly, how much energy will all of this take? How long will we retain access to that kind of energy? The future I envision for electronics looks rather different from that of the optimists, but I would welcome further discussion and enlightenment on this subject, including some more rigorous numerical analyses.

The next time I address this topic, we will consider organic (polymeric) electronics. Stay tuned...

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