By Mary Logan
How do cities concentrate energy and materials spatially? What is the relative emergy basis for modern cities, agrarian towns, and rural spaces? Do city dwellers use more or fewer resources than suburban or rural dwellers? Are big cities more sustainable in descent, as some propose, and how do we maximize empower in the future for our cities?
Spatial Concentration of Emergy
Cities concentrate energy and materials by importing energy, food, and materials through convergence of trade with the outside environs.
“Although there is energy in everything including information, we recognize that energies of different kinds are not equal, but can be compared by expressing everything in units
of one kind of energy required [Emergy]. In this way, human services are found to require thousands of times
more energy of ordinary kinds than do agricultural processes. The Emergy production and use per unit of time is called Empower. . . . The Emergy of one kind of energy required to generate a product or service of another kind of energy is the Transformity. The more energy transformation steps there are, the higher the Transformity. In an agrarian landscape, the resources of agriculture and nature are converged to support small cities. . . . [In fossil fuel based cities] the city processes reach out to surrounding zones in their interactions (Odum, Brown et al., 1995, pp. 5-6).
The central zones of cities return services to reinforce the rural system. Resources and people converge and diverge on the city in pulses, and people, information and money are concentrated in the centers. The emergy basis and zonation are a function of the fossil fuel basis, with increasing complexity resulting out of multiple levels of transformation. The largest cities embody the most levels of hierarchy, and the level of complexity that has been built up in large urban centers requires a global supply chain and high quality fossil fuels. One empirical test of this idea is history; urban pre-industrial man lived in cities of less than 1 million at the largest, with much less complexity. Now our largest megacities contain as many as 37 million people (Tokyo), with heavy reliance on electricity, computers, and transportation. The complexity and interdependency of infrastructure, employment and information exchange are a direct function of fossil fuels, and our megacities have grown become massive because of the competitive advantage of information and resource concentration found in cities, creating an influx of resources from greater and greater distances. Our megacities have many more people and roles embedded in layers of transformation at the high emergy end of the equation due to fossil fuels. The roles in a megacity are skewed towards information processing in areas of government, law, education, healthcare, and the financial-insurance-real estate industries. We can argue that the cultural behavior and values in megacities are different from more agrarian settings, with more competition, more inequity in salaries, looser values, more deviance, and a different perception of time.
Cities also create concentrated solid, liquid, and gas wastes (CO2 and incineration, for example), which they then disperse, often in concentrated form and at great distance. Cities are heat islands that produce large amounts of concentrated pollution. Odum once proposed that an ecological approach to waste disposal would be to disperse it across the landscape instead of concentrating it in waste dumps. That is the method that is used by nature, where everything is recycled naturally and eventually used. Dispersal of waste would create a feedback loop limiting wastes, as people would have to look at and be accountable to their mounds of trash. More recycling would occur. That dispersal happens somewhat in rural living settings already. Cars and tractors are kept for their spare parts, for example, which is more efficient and ecological than concentrating them in a dump. Some recycling from dumps is already occurring as descent begins. Sewage is successfully dispersed by dispersing dilute wastes through wetlands, increasing productivity and allowing nature to do the work of reprocessing.
What is the zonal empower of agrarian and urban cities? Who uses more resources? While fuel use decreases in city centers, the sum of empower and information increases due to transformity. And while the emergy/person decreases in city centers, that energy basis is only made possible with support from the lower hierarchical zones of agrarian support. If we view cities through an energy lens, the cities become terraced sets of hierarchical transformations. While fossil fuel use and environmental contributions may drop off at the center of cities, creating a seeming efficiency and low footprint, the emergy contained within the infrastructure of skyscrapers and the information and culture at city centers is immense. Money becomes less effective and prices are higher in city centers because money is circulated faster than emergy flows, especially these days!
Self organization generates spatial centers as part of energy hierarchy. One reason is that spatial concentration is a way of making transformed high quality flows of less energy have a commensurate feedback effect outward to reinforce the system. Examples are the information centers of cities, the water convergence at the mouths of rivers, and the concentration of organic matter in tree trunks. Concentrations are readily measured as areal empower density with values ranging from less than 1 E11 solaremjoules (SEJ)/m2/yr in wilderness to 50,000 E11 SEJ/m2/yr in city centers (Odum, 1998).
Emergy basis, hierarchy, and technocratic optimism
What is the emergy basis for a major metro city now, and how big of a city can we afford in the future? That question may depend in part on available local natural resources and cities’ current self-sufficient use of resources. In descent, some smaller, well-located cities may thrive, while larger cities facing unfortunate disasters at the larger scale will wink out. In one recent ecological evaluation of Beijing’s relative sustainability, Jiang et al. found that:
“. . . the Beijing city operated its activity on 0.31% renewable sources in 2004, and its emergy self-sufficiency ratio was 0.042. . . Based on the emergy analysis above, Beijing’s ecological economic status is characterized by: (1) heavy reliance on imported intensive fuels, goods and services; (2) high empower density and high environmental loading. (3) Most indicators of Beijing’s are located at middle level among the selected Chinese cities” (Jiang et al., 2009).
Beijing is one of our largest cities, and it is heavily dependent on high emergy resources and infrastructure. Our largest cities have little connection to their region of support due to fossil fuels, making them unsustainable without fossil fuels. Many technocrats disagree, however. Trust a technocrat living in a megacity to make this statement below.
“This straightforward observation has some surprising implications. It suggests, for instance, that modern cities are the real centers of sustainability. According to the data, people who live in densely populated places require less heat in the winter and need fewer miles of asphalt per capita. (A recent analysis by economists at Harvard and UCLA demonstrated that the average Manhattanite emits 14,127 fewer pounds of carbon dioxide annually than someone living in the New York suburbs.) Small communities might look green, but they consume a disproportionate amount of everything. As a result, West argues, creating a more sustainable society will require our big cities to get even bigger. We need more megalopolises. . . . “When we started living in cities, we did something that had never happened before in the history of life,” West says. “We broke away from the equations of biology, all of which are sublinear.” (Lehrer reviewing West in NYT, 2010).
While Lehrer (and West) recognize the dangerous exponential growth of cities, they fail to recognize the root cause, which is a century of overgrowth due to fossil fuels. These optimists attribute cities’ success to economies of scale and technological innovation, while failing to recognize the hierarchical base of energy support from the outer zones of cities and from nature that make life possible in city centers. The emergy basis of information centers is immense, accumulated through many transformations and levels of hierarchy. They also fail to recognize that the supposedly efficient city living is only garnered as a result of the unseen volumes of global imports that come into a smoothly running megacity, as suggested in Jiang’s Beijing emergy diagram above. Technocrats in academia and economists such as Glaeser (Goffman review) have great hopes of technocratic miracles to rescue us, with cities as the sustainable solution of last resort. Technocrats fail to see that technology is not equal to energy. Technology is a way to maximize power and harness resources. Technology is impossible without resources, and resources in cities come from afar. They bargain that while “urbanization is the problem, urbanization is the solution” (West, 2011). The technocrats fail to see the wider problem of growth, which is the real problem and not “urbanization.” If we replace the word urbanization in West’s statement with “growth” then the statement becomes illogical; “growth is the problem, growth is the solution.” The technocrats fail to find the larger scale problem, thus focusing on the wrong solutions. Technocrats are bargaining for sustainable growth through more people living in larger denser cities. Yet as descent begins, we already have examples of cities in decline in the US. New Orleans and Detroit are two early, obvious examples of how cities could collapse in descent. As economies and poverty worsens, small-scale restoration may become the norm as new building wanes. We do not have the resources to keep what we’ve got, much less rebuild as disasters at the larger scale impact our overcrowded cities.
Electricity and information are essential for our modern megacities. Electricity has a high transformity, approximately four times that of fossil fuels but much, much less transformity than information. Electricity is necessary for industrial and information societies, yet its use reduces resilience. Diversity of emergy sources decreases for complex infrastructure and organization due to heavy reliance on storages of fossil fuels, and as footprint broadens, resilience decreases. Thus, the more power we use, the less resilient we become. Electric power is an input to the industrial and information zones of large cities in the diagram above; without electricity cities would probably not support these zones. Is decentralization of our cities into secondary towns and suburbia the first step in descent, and how functional will suburbia become as it reintegrates into its region? Will the presence of regional grids create uniform descent, or will gaps and emergy centers create patchy resilience, similar to lights on a christmas tree?
In an empirical test of this idea, what would happen if we suddenly stopped the electricity in a city, in comparison with a rural setting? We would suddenly discover how dependent the city dwellers are on elevators, mass transit, safe lighting, pumped water, air conditioning and heating, and global supply chains. Similarly, waste removal for sewage, trash are essential in high density areas without capacity for using natural resources for recycling. What level of complexity is supportable without consistent electricity? City centers were historically situated at convergence zones for rivers where waters and their contents converge, or at sea coasts or mountain bases, concentrating natural resource. Successful information centers of the future may remain in areas where hydropower is used for electricity (with the caution that wherever we borrow from nature, we must knowingly trade off energy security for loss of productive ecosystems).
As cities with poor maintenance deteriorate, what level of density and emergy basis can we maintain? Megacities are history. Our largest city, Tokyo is starting to disperse and collapse demographically as a result of our over-reliance on nuclear energy and 20 years of economic contraction. Waning resources in descent will mean less concentrated, more agrarian cities. Hierarchies within cities will simplify. Job niches and some specialization will disappear. Losses in diversity may result in loss of resilience. Relationships within networks will change. Efficiencies may change, and much information will be lost. Total activities will decrease, and city patterns will reorganize, with smaller units, lower building heights, fewer cars, and less new construction. Transportation and housing will reorganize for better spatial distribution. As density decreases, greenbelts will reestablish (Odum, 1987; Ulgiati and Brown, 2009). Those changes are already occurring in the US. The size and complexity of our fossil fuel based cities is a direct function of the amount of entrained energy. In descent, less energy will mean smaller agrarian cities, with electricity as the defining line between successful higher emergy centers and dispersal. Cities are already downsizing in an arbitrary, haphazard fashion based on cost-benefit of values that are more appropriate to the growth phase, without attention to the contributions of nature. City planning based on emergy accounting could help to delineate alternatives to the growth model to design ecological cities of the future.
As cities decline, contract, and reorganize, the value systems of people in the cities will also change to a more cooperative mode, colliding with the old competitive values of the growth system. How will that play out?
Walking the New York Bedrock Alive in the Sea of Information
(Gary Snyder, Mountains and Rivers without End, 1997, p. 102)
. . . Gingko trees of Gondwanaland. Pictographs,
Petroglyphs, cover the subways–
Empty eye sockets of buildings just built
Soulless, they still wait the ceremony
that will make them too,
Provided with conduit, cable and plumbing,
They will light up, breathe cool air,
Breathe the minds of the worker who work there–
The cloud of their knowing
As they soar in the sky, in the air,
Of the sea
Of Information . . . .