Difference between revisions of "Paper - "cities as energy-using systems""

Dear Colleagues,

Here are some excerpts from the paper. Your comments or references are most welcome and appreciated.

Introduction

While there is a clear policy focus the greenhouse gas contributions of individual energy-using devices such as buildings and automobiles, there is comparatively less attention the larger systems in which they operate, including urban systems. Yet there is evidence that these systemic effects could potentially determine urban energy use to an even greater degree than the efficiencies of individual devices or components such as buildings and vehicles. This finding is therefore likely to have profound implications in guiding us to effective strategies for the reduction of energy use and the mitigation of greenhouse gas emissions per capita.

However, quantifying these systemic impacts, and our potential leverage over them, is significantly more challenging than the quantification of device/building energy use. This is the result of the many factors that interact in exceedingly complex and varying ways. There is a lack of clarity on systemic indicators that are more difficult to measure/quantify, such as the motivation of different trips people make (whether they are induced or mitigated by urban infrastructure), and energy flux effects as a result of urban density. Other factors include our premature level of understanding of qualitative factors, reasons for the choices made about housing and mobility, and people’s expectations towards comfort and mobility. Furthermore, we cannot yet fully quantify the impact of trade-offs such as living in a new, very energy-efficient, but suburban building vs. staying in older, less efficient more central urban housing that is associated with much lower transport needs. Such choices and factors determine fundamentally what urban design patterns serve best people’s comfort requirements, and how these could be optimized from a GHG emission perspective at the systemic level. At this point, we do not even have a comprehensive agreed international-scale model that fully accounts for the key drivers of urban systemic energy use and their interactions, or a taxonomy of main determinants of urban energy use – as opposed to the much more clearly understood technological efficiencies of energy-using devices.

The challenge is further complicated by the fact that urban energy use cuts across sectors and disciplines. The most typical organization of analysis of global and national energy systems is by economic sectors, i.e. dividing energy use into industrial, transport, service, and residential sectors – or similar categories with higher or lower resolution. This is a convenient frame for analysis since economic data are collected and reported in such categories, facilitating in-depth and comparable assessment across nations. This logic of organizing analysis and information is, for instance, was used in the Fourth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC, 2007).

However, a few key energy-using systems represent more important energy-using units than the boundaries determined by these economic sectors. An example that parallels that of urban systems is that of food systems. Energy needed for providing food for people is divided between agricultural energy use, food industry energy use, transport energy use, food retail energy use, and finally home energy used for cooking and refrigeration. Individual energy values represent a small share in their respective sectors, and thus food-related energy rarely leads energy policy agendas. However, if these are totaled, the combined operations to satisfy the nutritional needs of the population can amount to a very significant share of total energy consumption. Since there are many trade-offs between the agricultural energy use, transport use and cooking energy use for optimal policy design, food systems must be considered as a complete system rather than in the narrow analysis of food transporting vehicles and cooking device efficiency.

Urban energy systems are very similar. While policies have effectively been reducing energy consumption of buildings and automobiles, it is not clear whether some of these have not actually increased systemic energy use, such as increased need for mobility or energy transport. For example, there are notable cases of “green buildings” in more remote locations that require significantly higher transport energy for their users, and may therefore reduce any gains in energy efficiency, or even require increased net energy. A US case study by Environmental Building News (2007) is instructive: it examined the world’s first LEED Platinum building, the Chesapeake Bay Foundation’s Philip Merrill Environmental Center, which was relocated form an urban location to a suburban one. The study concluded that despite the greater efficiency of the building itself, “the additional energy use from more employees driving to work may well exceed the energy savings realized by the green building.” Indeed, the study cites research indicating that for an average US office building, the energy associated with transportation to and from the building may be as much as 30% more than the energy use of the building itself – and an even higher percentage for energy-efficient buildings. (Cited in Environmental Building News, 2007)

This is only one egregious example of how research is beginning to establish a clearer understanding of the important ways that the dynamics of urban systems affect greenhouse gas emissions. Indeed, as this paper will summarize, the research indicates dramatic potential reductions in energy use and emissions in relation to urban morphology and infrastructure.

The Energy Efficiency of Cities

We may begin with the recognition that cities, and other settlement types, can be treated as energy-using systems in their own right, with their own varying levels of efficiency. Clearly they are not mere aggregations of disconnected consumers of energy. Rather, we are well aware that the distribution of users affects energy consumption required for transportation, transmission efficiency, and perhaps other related factors. Moreover, we know that the urban form can produce or mitigate heat island effects, affecting cooling demands, and can correlate with more or less efficient building morphologies. More difficult to assess, the form can affect the behavior and consumption patterns of individual energy users, as they make decisions about a range of possible activities that affect energy consumption and emissions.

The evidence indicates that that these factors, and possibly others, create major variations in energy use per person, and major emissions and other contributions to climate change. The variation is not marginal, but, taken as whole, a significant percentage of all energy use: the evidence herein will suggest that it is perhaps on the magnitude of one-third of all energy use. Clearly, then, this is an important area of research and policy, and one that demands further development.

We will review herein the research that begins to tease out this story, and note the additional research that is needed. We will then proceed to the policy tools that can affect these variables, and the further work needed in that area as well – we believe, as a matter of great urgency.

Following are the individual urban factors that we can associate with lower energy use.

Density. This metric includes residential density (usually measured in persons per hectare, or sometimes households per hectare), and the density of other uses such as office. It can also be measured as a ratio of the area of building floors to land area – or “Floor Area Ratio”. Most studies look only at residential density, and then assume a mix of uses including residential, commercial and office.

The associations between density and energy use are striking. Studies consistently show that a doubling of density is associated with a reduction in energy use per capita of 30% or more (citations needed).

One of the strongest reductions is in transportation energy, which is particularly significant in areas that have higher personal automobile use. A classic study in the field (Kenworthy and Laube, 1999) demonstrated that transportation fuel consumption per capita declines by one-half to two-thirds as urban densities rise from four to twelve persons per acre (1.6 to 4.8 persons per hectare).

It is clear that much of this effect comes from the reduction in required driving that is associated with density. Studies show a remarkable consistent association between density and vehicle miles or kilometers traveled per household. In US research (Holtzclaw, 2001) the reduction is from about 15,000 miles per year (9,000 kilometres) at a residential density of 12 units to the acre (5 to the hectare) down to about 5,000 miles per year (3,000 kilometres) at 75 units to the acre (30 to the hectare).

Global examples are equally striking. The lower-density cities of the US (typically 10 persons to the hectare or less) use about five times more energy in motor spirit than the cities of Europe, which are in turn about five times more dense on average. This relationship holds even when adjustments are made for economic factors. (Kenworthy and Laube, 1999.)

But it is also clear that the direct emissions from automobile tailpipes are only the beginning of the story. For example, Canadian research shows that fuel production, vehicle manufacturing, vehicle maintenance, road construction and maintenance, and leakage of refrigerants, account for fully half again the emissions of tailpipes. (Summarised in Hydro-Québec, 2005.)

As noted above, often the energy savings from density meet or exceed the savings from energy-efficient building systems. For example, a compilation study by Holtzclaw et al. reported by New Urban News (2005) showed that the savings from an increase in residential density from 2.5 units per acre (1 per hectare) to 12 units per acre (4 units per hectare) exceeded the savings from the maximum rating of the US “Energy Star” certified heating and domestic appliances. Increasing density further to 100 units per acre (40 per hectare) doubled the energy savings per household.

We can observe the same dramatic variation in urban energy use associated closely with density, even within a single metropolitan area. This helps us to exclude such factors as climate variations, cultural differences, and other regional variations. A particularly striking example is from a study by the Bay Area Metropolitan Transportation Commission in the San Francisco Bay area of the US. It shows a dramatic tripling of energy use and CO2 emissions from transport, moving from the high-density neighborhoods of San Francisco, out to the sprawling subdivisions of the suburban edge. (Bay Area Metropolitan Transportation Commission, 2007.) The specific metric is CO2 emissions from transportation per household, but we can see a similar reduction in energy in other areas (as we will discuss in more detail below).

In this case we know a great deal about the factors that vary in the urban structure at the two extremes. We know that in the suburban edges, residents are required to drive long distances to work and to daily needs, and that they live more often in single-family detached dwellings on fragmented street networks. We know that in the high-density areas, residents can often walk or take transit to destinations that are, on average, much closer to one another, in a highly integrated street network. We also know that socioeconomic factors do not explain the disparity – the San Francisco area is hardly impoverished - nor does climate, regional culture or other factors, as the two locales are less than 40 miles apart.

Sprawling, fragmented urban patterns in Milpitas, CA., versus compact, walkable urbanism in San Francisco.

Intriguingly, this pattern of greater efficiency is not confined only to transport. Evidence that we will discuss below shows us that home energy consumption, embodied energy in construction and maintenance, and other more indirect sources of consumption also vary greatly as a result of urban form. And while density is closely associated with these other sources, each of them plays its own distinctive role.

Thus we may think of density as closely associated with, but not synonymous with, a number of other characteristics of urban structure. It is important to analyse these factors in their own right, and the aggregate and systemic contributions they make. We may list them as follows:

Transportation Efficiency. This includes all the factors that promote lower-energy use in urban transportation. They include: o Proximity of daily needs and activities. A good mix and distribution of workplaces, retail, offices and other daily destinations results in significantly shorter trips per day on average. . (Kenworthy and Laube, 1999.) o Availability of effective, safe and convenient public transport. An average single-occupancy passenger sedan consumes 4,200 kilojoules per passenger-kilometer, while a 40% occupied subway consumes 280 kilojoules per passenger-kilometer (just 6.7%). A 50% occupied diesel bus consumes 800 kilojoules per passenger-kilometre. (Various, summarised in Hydro-Québec, 2005.) o Walkability. Walking is a very low-energy form of transportation - even when taking into account the food required to fuel it. Assuming the fuel is cereal, walking consumes approx. 150 kilojoules per passenger-kilometer (Summarised in Hydro-Québec, 2005.) Walking trips fueled by a partial meat diet can be somewhat higher. Moreover, the beginning or end segment of a public transport trip is almost always a walking segment. Therefore a neighbourhood that obstructs walkability (through lack of sidewalks, dangerous streets and so on) is likely to obstruct transit use as well. o Bikability. Biking is also a low-energy form of transport, just 60 kilojoules per passenger-kilometre when fueled by cereals. (Various, summarised in Hydro-Québec, 2005.) o Urban network. An integrated rather than fragmented urban network results in shorter trips on average, and proportionately lower energy use per trip. It also promotes walking, as average walking trips are also shorter. [Pushkar et al., 2000, Dill, 2004.]

Infrastructure efficiency. It is intuitively obvious, and confirmed by research, that higher density reduces the allocation of required infrastructure per person. o Infrastructure construction and maintenance. A one-block street segment that embodies a typical 100 million BTUs will be allocated across 8 households at 12 million BTUs per household. But the same street segment serving 20 households will be allocated at only 5 million BTUs per household. (Allen et al., 2004.) o Operating energy. This includes lighting, pumping, signals, irrigation, and other urban infrastructure energy systems. Higher density neighbourhoods require proportionately less operating energy per capita. (Summarised in Hydro-Québec, 2005.) o Transmission efficiency and loss. Losses from transmission can be as high as 7% or more, and there is a clear association with urban form. Higher density means shorter distances and more efficient distribution. (Dong, 2006) o Cogeneration and district energy opportunities. These can be much more efficient than individual building systems – over 25% more efficient. They can also reduce transmission losses. (Allen et al., 2004.)

Energy demands from externalities. So-called “externalities” are factors that are not usually accounted for in normal economic transactions, but that are showing increasing signs of profound long-term economic consequence. We are beginning to see clearly tat the same is true for energy use and carbon emissions. o Loss of ecosystem services. A low-density urban form consumes more land and destroys areas that may be contributing valuable “ecosystem services”, such as water filtration, aquifer recharge and more. The loss of these services translates into yet more energy demand for pumping, water purification and the like. [Citation needed.] o Loss of agricultural lands. Nearby agriculture reduces food miles, increases nutritional value, generally lowers cost, and generally lowers energy use per calorie. More distant agriculture relies upon increasingly greater shipping and energy. [Citation needed.] o Heat island/albedo/vegetative cover per person. It is sometimes mistakenly assumed that low-density residential form reduces heat island effects. But when examined on a per-capita basis, the reverse is often the case – particularly for auto-dominated development patterns. The result is an increased demand on cooling equipment in warm areas and seasons. In addition, low albedo in pavement and roofing increases planetary warming, and loss of vegetative cover reduces CO2 absorption – both of which aggravate warming effects over time, and increase cooling demands yet further. [Citation needed.]

Associations between urban morphology and building morphology. Higher-density urban areas by their nature include more multi-family and attached dwellings. Thee have a number of energy efficiency advantages. o Urban building type, exposure and orientation. According to U.S. DOE data, space-heating requirements can be as much as 20 percent less on a square foot basis for dwellings in multi-unit buildings compared to detached structures. (Cited in Allen et al., 2004.) In addition, o Prevailing size, and economic factors in same. Residential units in higher-density areas are typically smaller on average, in large part because of the higher prices commanded by greater proximity. The increased cost of homes also may cause a shift away from other forms of consumer spending, toward home care and improvement. [Citation needed.] o Embodied energy in building materials. According to University of North Carolina research, attached dwellings have an average of 750,000 Btu per sq.ft. of embodied energy in their construction materials versus 790,000 Btu for detached dwellings – a reduction of 5%. (Cited in Allen et al., 2004.)

Other indirect factors. There are other topics that are more difficult to ascertain, but that seem equally critical in the final determination of whether people will locate in more compact, low-energy areas, and adopt lower-energy lifestyles. o Cognitive and behavioral factors. What factors will induce buyers to live in higher-density, lower-energy and lower-emissions neighbourhoods? What character of neighborhoods, of architecture? What will promote lower-energy habits and choices? Much more research is needed in this important subject, but we know that the success of these neighbourhoods in attracting and retaining residents over time depends on attractive architecture, durable high-quality construction, and access to parks and natural areas (Holtzclaw, 2001). o Induced demand. This is a well-known perverse effect of efficiency. As systems become more efficient, they also tend to become less expensive. The result is that people may be more likely to use them more, partially or wholly erasing the gains from efficiency. [Citation needed.] o Resilience and performance over time. History has shown that new technology does little good if it breaks down or becomes rapidly obsolete. In such a condition the embodied energy of its production can easily exceed any savings from its introduction. So too, buildings need to be able to adapt to new uses, while remaining durable and easy to repair and maintain. There is also evidence to suggest that buildings that reflect local identity and “naturalness” are more likely to be found appealing and worthy of care. [Citation needed.]

Thus, although much more research is badly needed, the research on urban systems is already painting a clear picture: denser, more compact, more walkable, more transit-served cities use dramatically less energy per capita, when adjusted for other factors.

What is the magnitude of the reduction available from urban systems design, and what is its percentage of the totality of energy use? Specifically, what is the magnitude of overall reductions available assuming we could move from high energy-using urban and suburban areas, such as those common in the US, to lower energy-using urban areas, such as those more common in Europe and Asia? Bearing in mind that the factors vary greatly, we can identify potential magnitudes of variations in the following key components:

Transportation. We have seen that the energy used in transportation per person can vary by as much as a factor of four. In the US, our model of high energy-using urban systems, energy for personal transportation is in the range of 62% of all transportation energy. (U.S. Environmental Protection Agency, 2005. Inventory of U.S. Greenhouse Gas Emissions and Sinks: 1990–2003. Washington, DC, Table 2-9.) Transportation itself is approx. 27% of all energy use. (Ibid.) Thus energy from personal transportation in the US is approx. 16.7% of all energy.

It follows that a wholesale move (the most ambitious possible scenario) from a US high-energy model to a model based on more compact, transit-served urbanism, could produce a reduction of up to three-quarters, or on the order of as much as a 12% reduction in overall energy use.

Embodied energy. As noted previously, “tailpipe energy” is perhaps only about 2/3 of total energy used by vehicles, including production energy, extraction and refinement of fuels, pavement and other transportation infrastructure, and other embodied energy. Following the logic above, this might be expected to add a savings of as much as 6%. Other embodied energy in infrastructure includes power, water and other utilities, and their construction.

The influence of building type. According to US Department of Energy research, multi-family homes in buildings with 5 or more units, the prevailing typology in higher-density areas, use approximately 40% of the energy used by single-family detached homes, the prevailing home type in low-density sprawl – a savings of 60%. (Sources: Energy Information Administration, Residential Energy Consumption Surveys, 1978, 1979, 1980, 1981, 1982, 1984, 1987, 1990, 1993, 1997, 2001.) Since US residential energy use is over 20% of all energy use, a complete change in building type for a hypothetical 50% of all housing stock could represent a maximum possible savings of up to 6% of all energy used. (EIA, 2005.)

Opportunities for cogeneration and district energy. A study by Eliot Allen of Criterion Planners, Portland, Oregon, suggests that these features can achieve energy savings of 25% or more in building energy consumption. (Allen et al., 2004) Again, residential buildings in the US consume over 20% of all energy, meaning that such features could achieve a maximum savings of 5% over high-energy urban areas.

Savings in transmission losses, leakage and other infrastructure efficiencies. Transmission losses can represent 7% or more of all electric power generated (US Cliimate Change Technology Program, 2003). A significant percentage of transmission loss can be attributed to dispersed users, requiring longer and more dispersed lines. (Dong, 2006) A similar impact occurs with leakage of water and other utilities, requiring additional energy use. Electricity generation is approximately 40% of all energy produced (EIA Data Table F1, 2008). Thus, a 25% reduction in transmission losses would amount to a savings of .7% of all energy use. Savings from reduced leakage of water and other utilities is likely to add fractionally to this savings.

Behavioral and lifestyle factors. These have proven difficult to quantify, but anecdotal evidence suggests they are major variables. Those living in higher-density urban areas seem to spend more time in low-energy activities and consumption patterns. Those who begin to use and enjoy some low-energy urban systems seem to increase their use of those and other systems over time. (Podobnik, 2009.) At present we are unable to assign a specific reduction potential to these factors, but we believe it is plausible to estimate a one to two percent savings.

Summary. Thus, the combined possible reductions in total energy use outlined above are on the order of one-third. This is certainly an attention-getting magnitude. Of course, it must be added that this is an optimum estimate figure. It does not reflect the fact that existing neighbourhoods would likely remain at or near their current energy levels until they can be redeveloped. The actual realistic achievement from such strategies on a global level may be perhaps half of this. Nonetheless, we suggest this is a dramatic and important target for reductions in energy use.

This is a particularly important finding for areas of new urban growth, which are common in the developing world. Given the pattern of American-style sprawl that is still common (see illustration), this growth is likely to increase overall emissions even further without dramatic changes.

But such systemic, thoroughgoing changes in urban form, in combination with more efficient equipment, building retrofits, renewable energy sources and the like, begin to point the way to more dramatic reductions in energy use, with similar opportunities to reduce greenhouse gas emissions.

Current patterns of urban growth in the developing world, using McDonald’s as a proxy for other very similar development now under way in these countries.

Strategies to Achieve the Available Reductions

Urban form develops slowly, and for this reason it often escapes the attention of those looking for rapid energy reductions. Yet the corollary is that urban form is a persistent energy user, and therefore any changes made now are likely to have a large and compounding effect over time. This is particularly important in the developing world, where urban growth is often dramatic and chaotic, and its impacts are set to shape global energy and carbon patterns for many decades to come.

Research is continuing into a number of tools to produce more compact, transit-served, walkable urban form. They range from age-old strategies (urban codes and regulations) to innovative strategies (incentives, certification systems). Following is a summary.

Urban codes. Such codes have existed for many centuries, and are associated with many of the best loved urban spaces (a famous example is Siena, Italy). So-called Euclidean Zoning codes have been largely responsible for the automobile-dominated, segregated development patterns of post-war sprawl. Recent innovations include form-based codes, which prescribe urban form that supports walking and transit. Transect-based codes such as the “SmartCode” combine form-based coding with categorization of regions into “Transect zones,” with appropriate features form the highest densities to the lower densities that will still prevail in agricultural communities and other more remote locations.

Other regulations and prohibitions. These familiar tools include land use regulations, such as urban growth boundaries, and prohibition of certain uses in certain locations. The UK prohibition of “out of town shopping” is an example. The goal is often to eliminate sources of high-energy and high-carbon activity, while leaving more desirable areas (such as inner-city locations) to attract development. Critics often charge that such strategies are cumbersome and often produce unintended consequences. Defenders respond that previous regulations actually encouraged inefficient patterns, and a new generation of regulations is needed now to correct the problem.

Plans and frameworks. Again, these are familiar tools, but new strategies are being incorporated. One is to target areas for transit and transit-oriented development. Another is to designate existing lower-energy and lower-carbon areas for protection and enhancement. Criterion Planners of Portland, Oregon has a planning tool to identify “cool spots”, as the most likely areas for lower-energy and carbon development.

Certification systems. These innovations generally provide a scoring matrix that gives points for factors discussed herein, such as density, mixed use, walkability, access to transit, and building type. The certification is a standard that developers and municipalities can use as a promotional tool. In some cases governments will use such systems to select preferred projects or to expedite approval – or in some cases, will apply them as outright regulatory codes. In the US the new LEED-ND system (Leadership in Energy and Environmental Design – Neighborhood Development) is attracting widespread interest. In Europe the BREEAM system is prominent, but there are dozens of other proposed systems at present.

Catalyst projects. These are projects deliberately created to trigger associated growth by others. Often these are public projects, or public-private projects. Examples are transit-oriented developments, model communities such as the UK’s “Eco-towns”, and government development projects in preferred locations.

Pricing signals. These include taxes, tolls, fees, surcharges, credits, deductions, offsets and the like. The economics of urban development may be thought of as its “operating system”, and evidence shows it is a system that is highly sensitive to cost differences. We know that motorists will choose to take transit when the cost of driving is increased with road tolls, parking fees and the like. Development patterns will change when the structure of costs and fees changes. Energy efficiency will increase as the cost of energy increases, through market processes, but also through carbon taxes and the like.

Other incentives. These may include award schemes, grants, education and public relation campaigns, policy reports and conclusions, research dissemination, and other non-pricing influences. These are increasingly recognised as important but previously under-appreciated contributors to decision-making.

Self-organisation management strategies. Although formal urban planning gets the most attention, the fact remains that most urban structures are made by many agents working to follow relatively simple rules in emergent collaborations. Biological science has Recent research has demonstrated that many of the most optimal urban structures have been made in this way as well. (Hillier, 2005; Batty, 2003.) Much productive research is being done in this area, to understand how such emergent and self-organising processes occur, and how we can exploit them to achieve more optimum urban performance. In many cases the strategies involve employing the tools discussed above, but doing so in a strategic way, taking a “systems approach”. This requires a different strategy for analyzing urban problems, and for understanding and managing “the kind of problem a city is,” in the famous words of the urban scholar Jane Jacobs.

“Toolkits.” Different cities and regions may find that different mixes of strategies work most effectively, or are most feasible within varying political and cultural contexts. Therefore it is important to offer a range of tools and strategies, and to allow local citizens to adapt them to fit. In California, the Local Government Commission (LGC), Congress for the New Urbanism (CNU), and Governor’s Office of Policy Research (OPR) have proposed a series of “charrettes” or community workshops to develop and apply custom tools and strategies to meet the statewide mandate for carbon reduction under California’s landmark AB32 and SB375 greenhouse gas reduction legislation. This and other jurisdictions around the world can be thought of as the “laboratories” where effective new approaches will be developed, and it is vital that they have good research at their disposal.

Conclusion: Policy Implications

We have seen that cities and suburbs are energy-using systems in their own right, and that they can use energy in dramatically more or less efficient ways. Moreover, because they tend to develop slowly, their structure can have a disproportionately large effect over time – but at the same time, they may escape the attention of those seeking rapid reductions.

This finding has important implications for policy to mitigate greenhouse gas emissions effectively. Put simply, cities and their form will necessarily be a major variable in any effective long-term mitigation strategy. The issue is particularly urgent, given the major construction of infrastructure now under way in developing countries, which is set to greatly affect emissions for many decades to come.

Yet in an indication of the challenge, recent debate in the USA, for example, has focused on economic stimulus spending on reconstruction of existing (in some cases low-density) transportation infrastructure. Many commentators have argued that this short-term focus has come at the expense of another stated long-term goal: the mitigation of climate change, through a new generation of economically viable low-E infrastructure. For some observers, this is a reflection of a major and persistent policy “disconnect” between short-term economic goals, on the one hand, and long-term environmental goals on the other – but goals on which future economic viability clearly depends.

The reasons for this disconnect are understandable. As we have noted, urban systems are highly complex, and it is difficult to tease out the many factors that contribute to their behaviors. It is also difficult to identify our leverage over these factors, and for those factors with high leverage, the mix of policy tools that can effectively manage these morphologies, where more conventional top-down planning methods have proved inadequate. Lastly, it is exceedingly difficult to marshal the political will to implement the necessary policies -- in the USA and elsewhere -- as recent history has sadly demonstrated. The new administration in the USA has shown that it has accumulated a great deal of political capital, but also that it is going to be parsimonious with that capital in its early months.

Yet as a number of investigators have noted, such systems issues are precisely the sorts of challenges that must be met for an effective global response to the crisis of climate change. The problem is not a narrow technical one, but a broad, systemic and political one. It is precisely those systems that are complex, interactive, and collective that must be managed successfully. For researchers, this means identifying both the factors that affect emissions, and the tools that can manage them, in a politically feasible environment. This is a daunting challenge, but a most necessary one.

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Thanks to Eliot Allen at Criterion Planners for these references (to be edited/selected from):

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Burby, R.J., and Bell, A.F., editors, Energy and the Community, Ballinger Publishing Co., Cambridge, Massachusetts, 1979.

Burchell, Robert W., and Listokin, David, Energy and Land Use, Center for Urban Policy Research, Rutgers University, Piscataway, New Jersey, 1982. Curtis, Fred, editor, Considerations and Opportunities for Energy Conservation in Urban and Regional Planning, Conference Proceedings March 9-11, 1979, Queen's University, School of Urban and Regional Planning, Kingston, Ontario, Canada, 1979. Harwood, Corbin Crews, Using Land to Save Energy, Environmental Law Institute, Cambridge, Massachusetts, 1977.

Jackson, C.I., editor, Human Settlements and Energy, Pergamon Press, Oxford, 1978. Keyes, Dale L., Land Use and Energy Conservation: Is There a Link to Exploit?, in Energy and the Community, Raymond J. Burby, and A. Flemming Bell, (eds.), Cambridge: Ballinger, 1979. Keyes, Dale L., and Peterson, G., Urban Development and Energy Consumption, Working Paper No. 5049, Urban Land Institute, Washington, D.C., 1977.

Lamm, J., Energy in Physical Planning, Swedish Council for Building Research, Stockholm, Sweden, 1986.

Owens, S., Energy, Environmental Sustainability, and Land Use Planning, in Sustainable Development and Urban Form, M.J. Breheny (ed.), London: Pion, 1992. 011/617 2 3/2/2009

Sewell, W.R. Derrick, and Foster, Harold, Analysis of the United States Experience in Modifying Land Use to Conserve Energy, Environment Canada, Lands Directorate, Ottawa, Canada, Nov. 1979.

Sewell, W.R. Derrick and Foster, Harold, Energy Conservation Through Land Use Planning, Working Paper No. 6, Environment Canada, Lands Directorate, Ottawa, Canada, August 1980.

Systems Consultants, Inc., Energy and Land Use, U.S. Department of Energy, Argonne National Laboratory, December 1981.

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Anderson, W., et al., Urban Form, Energy, and the Environment: A Review of Issues, Evidence, and Analytical Approaches, McMaster University, Hamilton, Ontario, Canada, April 1993.

Campbell, Tim, Energy, Efficiency, and City Size: Some New Questions, Working Paper No. 367, Institute of Urban & Regional Development, University of California, Berkeley, California, December 1981.

Chibuk, J.H., Energy and Urban Form, Ministry of State for Urban Affairs, Information Canada, Ottawa, Canada, 1977.

Cotruvo, Thomas D., Energy Conservation and Urban Planning Implications for Land Use Patterns, University of Pennsylvania, Department of Civil and Urban Engineering, Philadelphia, Pennsylvania, May 1976.

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Edwards, J.L., and Schofer, J.L., Relationships Between Transportation Energy Consumption and Urban Structure: Results of Simulation Studies, Department of Civil and Mineral Engineering, University of Minnesota, Minnesota, 1975.

Hix, John, Energy Demand of Existing and Future Land Use Patterns, Royal Commission on Electric Power Planning, Toronto, Canada, 1977.

Keyes, Dale L., Urban Form and Energy Use, Land Use Center Working Paper 9-5049-02, The Urban Institute, Washington, D.C., September 1975.

Knowles, Ralph L., Energy and Form: An Ecological Approach to Urban Growth, The MIT Press, Cambridge, Massachusetts, 1974.

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Middleton Associates, Urban Form and Energy Consumption, Ministry of State and Urban Affairs, Ottawa, Canada, 1979.

Owens, Susan E., Energy Demand and Spatial Structure, in Energy Policy and Land Use Planning, D. R. Cope, P. R. Hills, P. James, eds., Pergamon Press, pp. 215-240, Oxford, England, 1984.

Owens, Susan E., Energy and Settlement Patterns, Built Environment, Vol. 5, No. 4., pp. 282-286, circa 1980.

Owens, Susan E., Energy, Planning and Urban Form, Pion Publishing, London, 1986. Schneider, J., et. al., Defining Urban Form/Transportation Energy Relationships for Use in Planning Transportation Energy Conservation Strategies in Urban Area, U.S.

Department of Transportation, University of Washington, Seattle, Washington, 1983.

Small, K.A., Energy Scarcity and Urban Development Patterns, International Regional Science Review, No. 5 2, pp. 97-119, 1980.

White, Anthony, Energy and Urban Spatial Form: An Selected Bibliography, Bibliography A- 1713, Vance Bibliographies, Monticello, Illinois, 1986.

Anderson, R., and Samartin, A., Interdependence Among Housing, Heating and Transportation in Cities, Swedish Council for Building Research, Stockholm, Sweden, 1979.

Carrier, Roger, Energy Conservation Through Urban Transportation Planning, Pennsylvania Transportation Institute, Harrisburg, Pennsylvania, May 1975.

Cheslow, M.D., The Effects of Urban Development Patterns on Transportation Energy Use, The Urban Institute, Fifth National Conference on the Effects of Energy Constraints on Transportation Systems, Washington, D.C., 1978.

Duensing, E., Energy Conservation and Its Effect on Land Use Planning, Vance Bibliographies, Monticello, Illinois, 1981.

Levinson, H.S., and Strate, H.E., Land Use and Energy Intensity, Transportation Research Board, Washington, D.C., 1981.

Peskin, Robert L., and Schoffer, Joseph, Urban Transportation and Land Use Policies and Energy Conservation, Proceedings, IEEE Conference on Transportation, Washington, D.C., 1976.

Putman, S.H., Transportation Energy Conservation Through Land-Use Planning, Report No. DOT-1-82-50, Department of Transportation, Washington, D.C., 1982.

Sharpe, R., Improving Energy Efficiency in Community Land Use - Transportation Systems, First International Conference on Energy and Community Development, Athens, Greece, 1978.

Sharpe, R., et al., Energy Conservation in Land-Use and Transportation, Proceedings of theEnergy Conservation in the Built Environment Conference, pp 49-79, Department of Environment, Housing and Community Development, Australia, 1979.

Steadman, P., Configurations of Land Uses, Transport Networks and Their Relation to Energy se, Centre for Configurational Studies, Open University, Milton Keynes, England, 1980.

U.S. Department of Transportation, Transportation Energy Conservation Through Land-Use Planning, Report No. DOT-1-82-50, Washington, D.C., 1982.