|
|
|
(The following chapter summaries were written in February 1995.) Technoecosystem is our human-controlled life support system, taken as a whole. An ecosystem of machines. From the air, we can see it as a new form of life, rapidly evolving and spreading across the planet. It competes with, cooperates with, and engulfs all the other natural systems. Human beings are at the controls, but only dimly conscious of what we are doing and its consequences. If we become more aware of technoecosystems at this larger level, perhaps we will manage them better and more harmoniously, for the benefit of all human beings, and the preservation of beautiful nature. This book introduces technoecology ideas,
and uses them to look at human technoecosystems for exploiting the heat within the earth.
From this larger perspective, geothermal energy looks less attractive than the business
people portray it. The resource is small and would only last a short while. And its
environmental consequences would be great. Solar energy is a better idea. Chapter Summaries
Original Abstract
<Return
to chapter titles> Rapidly evolving technology for exploitation of geothermal resources (heat fluids, and chemicals) is reviewed within the framework of technoecology. Water is vital to geothermal technoecosystems as heat storage and transfer medium, as coolant for thermodynamic cycles of power production and distillation, and as chemical reactant and solvent. In arid lands, fresh water can be an especially valuable output for agricultural, industrial, and municipal use: geothermal technoecosystems are carefully adapted to water availability and needs. Systems planned or established in arid developing regions and Imperial Valley, California, are presented as detailed case studies. Where resource conditions are favorable, geothermal technoecosystems can produce large amounts of power, water, space and process heat, and industrial chemicals in a short time. However, geothermal reserves are finite and nonrenewable at projected exploitation rates. For billions of years geothermal heat has driven dynamic geological ordering processes through a cascaded hierarchy of convection systems. Geothermal technoecosystems outcompete geological systems in heat extraction. Hence ever-deeper geothermal resource exploitation threatens geological systems of ever-larger scale with irreversible modification and possible extinction.
1. Introduction to Technoecology <Return to chapter titles> Taking off in a small private jet over the desert around Tucson. "A roar, the crush of acceleration, and we gently part from the surface and slide up into the clear, blue- vaulted atmosphere. Airport vehicles and buildings fall behind, looking like miniature toys." Macrovision, the direct experience of the technoecosystem in its natural setting. Human beings (and their politics, ideas, and money) are invisible from the air. We just see the life support system. And it looks alive, like an ecosystem of machines. Cars, airplanes, and spacecraft look like animals which crawl or fly. Houses and factories look like mushrooms or coral reefs. These can be called technoorganisms, and classified as technospecies. They are diverse, they interact, and they evolve, just like biological organisms and species. They comprise what we can call technolife. Technoecosystem's outer boundary is the outward limit of conscious (or I would now add unconscious) human control. Its inner boundary is the human skin. (Though this boundary is very fuzzy -- should we include surgical implants and contact lenses?) Technoecosystem is humanity's exoskeleton, a vast aggregation of tools and controlled systems. It is expanding to include even the ocean and atmosphere. "Man" doesn't use most of the resources (metals, oil, concrete, etc.), or create most of the environmental consequences; the technoecosystem does, under human control. This viewpoint is helpful in breaking our identification with and attachment to our roles in the technoecosystem. We are not our machines. We can put them on and take them off like clothing. We are not really pilots or businessmen or farmers. We are so much more. We can change our systems or leave them or watch them fail, and yet still be ourselves. And our pyramids and cars, like fossils, crumble long after we are gone. As we fly around the world, we see people everywhere. Some live in low-energy, others in high-energy technoecosystems. Low energy technoecosystems are mostly biological, with less mechanical technomass (mass of technoecosystem, like biomass) and metabolism, and proportionately more human labor. People are more aware of their support systems and environmental effects. And no plush cybernetic control rooms are provided. In contrast, high energy technoecosystems have vast mechanical technomass and metabolism per inhabitant, with luxurious cabins and high-tech control rooms. Most inhabitants are highly specialized and unaware of the whole systems around them. Technoecosystem can be seen as a system of levers which allow human beings to control ever larger (and more sophisticated) masses and energy flows. Here are some mass and power (energy flow or metabolism) comparisons:
Technoecosystem is a medium. Like water to a fish (or that wonderful energy within our breath), it is invisible to most of us, until it changes or goes away. Yet it supports our lives and influences and manifests all our activities. Almost everything we do in our daily lives has to do with the technoecosystem. If I were to greatly simplify the technoecosystem parts that high level executives use so well in their work, they would include aircraft (and their worldwide manufacturing, maintenance, navigation, and airport systems), cars (and their repair and road systems), houses (and their utility systems), video and audio equipment, computers, research & development facilities, meeting halls and hotels around the world, and the life support systems of all the people they touch. Yet even though they are using all these resources maximally, to most people it just seems like they are showing up personally at a meeting. The perception of technoecology is actually very natural. Children see cars and airplanes as animals and birds. We climb into different machines the way an aborigine might put on a wolf or eagle costume. We use biological terms for airplane parts: nose, wings, skin, tail. And we use animal names for different varieties of vehicles: (Flying Tiger, Cougar, Pinto, Caterpillar). Technoecology could be an improvement or addition to many already-existing philosophies. It is bigger and less money- blinded than economics. It takes bionics (designing machines after animals and plants) to a higher ecosystem level. And it provides a context for expanding biology to include technology. Technoecology, along with Knowledge, helps me feel at home in any factory, laboratory, mine, farm, city, or village anywhere in the world. Human beings all have technoecosystems in common. Technoecosystems and technoorganisms are so similar to biological systems. Airplanes are becoming more and more intelligent and alive. Technoorganisms evolve, incorporate new materials and physical principles (metals, electricity), develop group behaviors (traffic jams), open up and move into new niches (underground, undersea, orbital space), form energy chains and pyramids (oil wells to refineries to gas stations to cars), undergo succession (from coal-fired systems to oil- fired systems), and go extinct (autogiros, almost). On the large scale, technoecosystems exploit energy niches. Originally technoecosystem worked off the biological world. Then it began to exploit water power, and now various fossil fuels. People are now worried that the oil niche could run out, and that massive coal use would ruin the climate by releasing too much carbon dioxide into the atmosphere. The search is on for a new energy niche to support the technoecosystem. Nuclear looks too costly and toxic in a larger view. Geothermal (as I show in this book) is too limited and damaging. Solar (as I describe in the second book) looks to me like the best option: safer, renewable. And it mimics the biosphere, which is almost completely supported by solar energy. Solar cells and collectors are the technological analogue of chloroplasts. If some other niche should open up due to invention of something like a "free" energy motor, we really need to ask two questions before jumping into another frenzy of blind short-term exploitation: (1) How long could this niche last? and (2) What are the long-term environmental effects? Technoecosystems and technoorganisms in deserts evolve to create and exploit water niches. They gather, store, conserve, and minimize use of water, much like desert plants & animals. Military technoecosystems have evolved throughout history to use the most sophisticated materials and technoorganisms, the most purposeful organization, and the most intensive energy flows. They are designed to disrupt, destroy, and control each other and the civilian technoecosystems which support most human beings. They may be wasteful, and their whole purpose may be terrible, but the details of their evolution and functioning are fascinating and instructive. If we use similar design principles and methods to design civilian technoecosystems, and if the people, through inner experience, learn to think differently and have higher priorities than personal power, then all human beings could have higher levels of life support than they do now. 2. Earth Cycles (Rock Engines) <Return to chapter titles> People in the 1970s thought that about 20 percent of the heat in the earth is left over from the planet's formation, and 80 percent is generated from decay of radioactive elements. There is a lot of heat in the earth. But its entire flow to the surface of the earth is only about 4 or 5 times the fuel energy used by all world technoecosystems, and 1/2,000th the power of all sunlight striking the surface. This very diffuse geothermal heat drives a hierarchy of self-organizing heat engine convection systems which progressively concentrate the energy and power flow. The first and largest engine is convection of the mantle, which moves the continents around and makes mountains. This concentrates thermal power 2 to 20 times normal at hotspots, spreading ridges, and subduction zones. The second engine is formation and rising of molten rock in these thermal regions, resulting in magma bodies and volcanos. This locally concentrates thermal power from five to a million times normal. The third and last engine is convection of hot water in these volcanic regions, creating hot springs, geysers, and mineral deposits. This locally concentrates thermal power from ten to a billion times normal. Thus, thanks to these heat cycles, usable geothermal energy and power concentrations are found in a few very small areas of the globe. In this chapter I review the several types of heat concentration (resources), ranging from hot rock to dry steam. Generally, due to the hierarchy of heat cycles, the more concentrated and easier to use a resource is, the rarer and smaller it is. But it is important to remember that this heat is not just sitting there waiting for us to exploit it. It is always doing something, running the engines of the earth. Geothermal energy exploitation can interfere with the engines of geology. 3. Geothermal Technoecosystems <Return to chapter titles> This chapter is a comprehensive technology review, covering the many technologies, technoorganisms, and technoecosystems evolving to exploit the geothermal energy niche. Until recently, natural heat flows at the surface were used in small localized systems for cooking, bathing, or heating buildings. Flows were never used faster than provided by nature. But now large industrial technoecosystems seek to pump ever larger amounts of steam, hot water, and heat out of finite reservoirs in the earth, at flow rates much higher than nature replenishes. Industrial geothermal exploitation is in many ways similar to the exploitation of oil, although high quality geothermal concentrations are much more limited. Both use similar sophisticated exploration technologies: chemical sensing (analogous to tasting & smelling), remote sensing (like seeing) from planes and satellites, and drilling (like touching & feeling). It is like hunting for big animals. Both use similar underground drilling, well development, pumping, and storage technologies to suck the energy out of the ground, like killing and carving up "big game" animals. As with oil, geothermal energy can be converted by complex technoecosystems into many portable forms of fuel, electricity, chemicals, and fresh water to feed into the global technoecosystem. Unlike oil, geothermal energy is usually used or converted right on the spot. Like oil, geothermal exploitation has many adverse environmental effects. And like oil, geothermal technoecosystems are evolving to exploit ever larger and less concentrated resources, to the limit of profitability. In many cases, due to politics or economic manipulation, geothermal exploitation is subsidized by the global technoecosystem so it looks profitable when it really isn't. 4. Limits of the Niche <Return to chapter titles> In this chapter I show clearly how very limited the geothermal energy niche is. The metabolism of just the bodies of all the world's people is almost twice the heat flow of all the world's volcanos, five times the heat flow of all hydrothermal systems, and twenty times the average power of all earthquakes! And the mechanical power of the global technoecosystem is ten times greater than that. Clearly, exploitation of all geothermal resources at their natural rates would make an almost insignificant contribution to powering the technoecosystem. The world's total exploitable high quality geothermal energy storage is one hundredth of the total original oil reserves. So even if geothermal resources were extracted at rates much faster than sustainable, they would not last long. So the flows and storages are small. And at the same time, geothermal exploitation has severe environmental effects: pollution of land, air, and water, destruction of hot springs and geysers, land subsidence, and possibly earthquakes. Over the long term, geothermal exploitation could severely damage the heat engines that drive geological systems. One might argue that, except in special cases, geothermal exploitation is a waste of resources. 5. Imperial Valley <Return to chapter titles> This is a detailed case study of exploitation activities and plans for one area of natural geothermal heat concentration, the Imperial Valley-Mexicali region of southern California & northern Mexico. In the 1970s, several utility companies, oil companies, and the U.S. Bureau of Reclamation descended on this area to explore and seek to exploit the geothermal resources. I show in detail that here, too, the resource flows and storages are small, and that the costs and environmental consequences of full-scale exploitation would be great. Other than continued power production at a plant in Mexico (with the best resources), I don't think much has happened here geothermally in the last 20 years. 6. Developing Regions <Return to chapter titles> In this chapter I review ideas and plans that people had for exploiting geothermal resources in developing regions. The goal was to expand the technoecosystems that support the human populations in these countries. The trouble again is that geothermal resources in these areas, as everywhere, are highly localized, rare, and limited, costly to exploit, and damaging to the environment. Nevertheless, in a few places, high quality resources can be exploited for a limited time to enhance the life support of local people. Unlike in the United States, existing mechanical technoecosystem energy flows in these areas are so small that a little added energy will go a long way. So geothermal energy could provide a local and temporary energy boost while the global technoecosystem seeks a new, sustainable long-term energy niche. In most places, solar is still a better idea. 7. Epilogue <Return to chapter titles> A poetic vision of flying back home over Tucson at night. "Runway lights flash... to guide us in. Airport toys grow large again. We decide on a place for dinner as the wheels smoothly meet the surface. Where shall we fly next?" |
