Profligacies of Scale
The logic applied in last week’s post to photovoltaic solar power can be applied more generally to a fairly wide range of technologies that can, under the right circumstances, provide a modest supply of electricity to power those things for which electricity is really the most sensible power source. I want to talk about a couple of those in tthe weeks to come, partly for the sake of completeness, partly because the options I have in mind offer some distinct advantages, and partly because touching on a series of examples will make it easier to grasp certain common themes that aren’t often addressed on those rare occasions when discussions of the future of technology manage to make it out of the realm of popular mythology in the first place.
I don’t mean that last comment as a joke, by the way. If mythology can be defined as the set of stories that people in a given society use to make sense of the universe and themselves, contemporary beliefs about the future of technology in the cultural mainstream of the industrial world fill that role, doubled, tripled, and in spades. Those of my readers who have come to take the challenge of peak oil seriously, and tried to discuss it with family members, coworkers, and friends who haven’t yet grappled with the issues themselves, can testify just how forcefully most of these latter cling to the belief that some technological gimmick or other will bail us out.
Technology, for a great people nowadays, is their source of meaning and their hope of salvation. Most liberals, conservatives, atheists, and plenty of people who think they belong to some other religion all put their trust in the great god Progress and wait prayerfully for him to bring a future that, they insist, must be better than the present. However poorly founded that faith may be, it plays an immensely important role in today’s industrial cultures, and the death of Progress in our time thus bids fair to deal the same shattering blow to our present certainties that the death of God announced by Nietzche measured out to the equally comfortably certainties of the nineteenth century.
If anything, the approaching experience may be the harsher of the two. What Nietzche was saying, stripped of his ornate imagery, was that the people of Europe in his time no longer believed in the Christian myths and doctrines they claimed to accept, and needed to own up to the anthropocentric cult of power that had become their actual religion. That may have been true; still, it’s one thing to realize that you no longer believe things you were raised to think were good and right and true; it’s quite another, and far more devastating, to believe in something with all your heart and have it disproved right in front of your eyes. The religion of progress claims to be justified by works, not faith; during the three centuries or so of technological expansion, the apparent confirmation of the myth gave it immense strength; as the age of progress ends and we enter on three centuries or more of technological regress, the resulting body blow to our culture’s fondest beliefs and hopes will dominate the cultural psychology of an age.
It’s the effort to avoid that profoundly unwelcome experience that drives current attempts to insist that we can maintain our contemporary lifestyles, and even provide them to the population of the world’s nonindustrialized (and never to be industrialized) countries, using renewable energy sources. That same effort drives plenty of other exercises in futility, to be sure, and many of them are a good deal more dysfunctional than the dream of a world of middle class comforts powered by wind turbines and solar panels. Still, if we’re going to get beyond the mythology of a dying religion and talk about the future in more useful terms, it’s crucial to start by owning up to the fact that renewable sources are not going to allow anyone to maintain the kind of extravagant energy-wasting lifestyle that most people in the industrial world think of as normal.
What they can do instead is rather more valuable. There are certain technologies that are either dependent on electricity, or are easiest to provide using electricity, that contribute mightily to human welfare. (Long range radio communication is an example of the first kind; refrigeration for food storage is an example of the second.) If these technologies can get through the present crisis in a sustainable form, they will contribute to human welfare as far into the future as you care to look. Renewable energy sources that provide a modest amount of electricity on a local scale can keep a good many of these technologies going, and if enough people here and now either learn how to build and maintain renewable systems on that scale, on the one hand, or learn how to build and maintain the technologies themselves on the same modest and local scale, on the other, our civilization may actually accomplish the surprisingly rare feat of adding something worthwhile to the long-term toolkit of our species.
The modest amount and the local scale are vital to any such project. Right now, anyone with a fairly good set of hand tools and a good general knowledge of electricity, carpentry, and metalworking can build a wind turbine for a few hundred dollars. I can say this with some confidence because I helped do exactly that, for a good deal less, while at college in the early 1980s. The turbine itself was basically a two-blade propeller cut, shaped, and sanded from a block of fir; the conversion of rotary motion to electricity was done by an alternator salvaged from an old truck; the tail that kept it facing into the wind, the safety shutoff that swung it out of the path of the wind when the wind velocity got too high, and the tricky doodad that allowed it to turn freely while still getting electricity down to the batteries in the little shed at the base, were all fabricated out of scrap parts and sheet metal. We used a disused power pole to put the turbine up where the wind blew freely, but if that hadn’t been there, an octet truss tower – one of Bucky Fuller’s better designs – could easily have been put together out of readily available hardware and bolted onto a hand-poured concrete foundation.
The design wasn’t original, not by a long shot; half a dozen old appropriate tech books from the Seventies have the same design or its kissing cousin, and it’s one of a half dozen or so standard designs that came out of the ferment of those years. The most important difference was between horizontal axis from vertical axis models. A horizontal axis wind turbine is the kind most people think of, with blades like a propeller facing into the wind and a tail or some other gimmick to pivot it around in the right direction. A vertical axis wind turbine is less familiar these days, though you used to see examples all over the place back in the day; the business end looked either like one side of an eggbeater – the Darreius turbine – or an oil drum cut in half lengthwise, and the two sides staggered around the vertical shaft – the Savonius turbine. Some of the standard designs yielded high speed and low torque, which is what you want for generating electricity; some of them produced high torque and low speed, which is what you want for pumping water or most other uses of mechanical power.
All the information needed to design and build one or more of the standard models is easy to come by nowadays – literally dozens of books from the time cover the basic concepts, and it’s far from hard to find detailed plans for building your own. It’s also not too difficult for those who lack the basic technical skills to find small wind turbines of quite respectable quality for sale, though the price is going to be a good deal more than you’d shell out for an old truck alternator, a chunk of fir six feet by eight inches by four inches, and the rest of the hardware we used to cobble together our turbine. Either way, if you live in an area with average winds and your home isn’t surrounded by tall trees, steep hills, or skyscrapers, your odds of being able to run a respectable 12 volt system are pretty good.
Still, it will come as no surprise to regular readers of this blog that very little of this wealth of practical information receives much in the way of attention nowadays. Instead, the concept of wind power has been monopolized by a recently minted industry devoted to building, servicing, and promoting giant wind turbines that provide electricity to the grid. The giant turbines have their virtues, no question; compared to most other energy production technologies, certainly, they’re safe and clean, and their net energy yield is a respectable 8 or 9 to 1, which beats the stuffing out of most other alternative energy sources. Still, the idea that serried ranks of giant wind turbines will enable us all to keep on using energy at today’s extravagant rates runs headlong into at least two difficulties.
The first difficulty is intermittency. A wind turbine, obviously enough, produces power only when the wind is blowing, and it’s a safe bet that no matter where you put turbines, the wind won’t always be blowing. That wouldn’t be a problem at all if Americans were used to using electricity when it happens to be available, and doing something else with their time when it’s not, but that’s not the way Americans do things any more. Just now, intermittency isn’t much of a problem, since modern gas-fired power plants can be cycled up and down promptly to respond to any shortage of power from the turbines, but if your plan is to replace the gas-fired plants (and the coal-fired ones, which can’t be cycled up and down so quickly) with wind turbines, you’ve got a problem. You have an even bigger problem if you want to rely on solar as well as wind, since then you’re dependent on two intermittent energy sources, and when they both go down at the same time – as, by Murphy’s law, they inevitably will – you’re left with no power going into the grid at all.
The second difficulty, as discussed in previous posts here, is complexity. Those giant turbines, it bears remembering, are not made out of spare truck alternators, blocks of fir, and other readily accessible and easily managed parts. They are triumphs of modern engineering, which means in practice that they depend on baroque supply chains, high-tech manufacturing processes, and massive investment, not to mention plenty of fossil fuels and, more generally, a society that has plenty of cheap energy to spare for projects on a gargantuan scale. Nor is a giant wind turbine sitting all by itself on a hilltop particularly useful to much of anyone; it gains its economic viability through connection to the electrical grid, which is itself an immense technostructure with its own even more sprawling supply, manufacturing, and investment requirements. If industrial society finds itself unable to maintain any one of the factors that make the grid and the giant turbines possible, then it doesn’t matter how useful they might be; they won’t be around.
Homescale windpower systems suffer from the intermittency issue, but then so does nearly every other option for providing electricity on that scale, and we’ve already discussed at some length the solution to it: get used to using electricity when it’s available, or to storing up modest amounts of it in inexpensive storage batteries and using that supply sparingly. The challenge of complexity, on the other hand, is not something a homescale windpower system has to deal with at all. Even in the absence of salvageable alternators, and there are quite literally hundreds of millions of them lying unused in junkyards across the United States, a generator that will turn rotary motion into direct current is not a challenging project. I built a simple one in elementary school, for example, and although it wasn’t really suited to wind turbine use – most of the structural elements were made from paperclips, with a toy horseshoe magnet to provide the field, and the amount of current it produced was just about enough to get a decent glow out of a very small light bulb – the principle can readily be scaled up.
In the kind of future we can realistically expect, in other words, homescale windpower will almost certainly be a viable technology, while giant wind turbines of the modern sort almost certainly won’t. Now of course it’s a safe bet that the windpower industry as it now exists will keep on building, servicing, and promoting giant wind turbines as long as it’s possible to do so, so the small chance that the giant turbines might actually be viable is covered. What isn’t covered yet is the very large chance that small wind turbines of the sort that can be built and maintained in a basement workshop could provide a real benefit during the difficult decades ahead of us.
In order to respond to that range of possibilities, homescale windpower units need to find their way back into the conversation of our time and, more importantly, up above the rooftops of homes across the modern world. Professionally manufactured wind turbines of the right scale are a good start, and those green wizards in training who have the money and lack the fairly modest technical skills to build their own could do worse than to buy and install one. Still, there’s also a huge role here for the homebuilt turbine, and for those individuals whose willingness to get to work shaping turbine blades and bolting together octet truss towers might, as things unfold, lead to a future career.
Promoters of giant wind turbines, and for that matter of centralized power generation schemes of all kinds, tend to talk quite a bit about economies of scale. In an expanding economy with a stable or growing resource base, that sort of talk often makes sense, though the extent to which those economies of scale are a product of direct and indirect government subsidies to transportation, financing, and large businesses generally is not something economists like to talk about. Still, in a world facing economic contraction, resource depletion, and a loss of complexity potentially capable of rendering a great deal of today’s infrastructure useless or worse, the balance swings the other way. In the face of a future where small, cheap, localized approaches that are sparing in their use of resources, relying on massive, expensive, centralized, resource-intensive power plants of any kind is not an economy but a profligacy of scale, and one that we very probably will not be able to afford for much longer.
What do you think? Leave a comment below.
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