تصاویر پیشگویانه از شهر آینده-زمان و فضا برای توسعه پایدار در استکهلم

This paper presents and discusses a backcasting study for Stockholm 2050. The focus is on developing images of a future where Stockholm citizens have sustainable energy use—here defined as a 60% reduction per capita over a 50-year period. The perspective is that of households, so all energy is allocated to individuals’ activities rather than being discussed from a sector perspective. Six images of the future are developed by combining a space dimension (three versions of changes in urban structure) and a time dimension (two versions of people's life tempo). Added to this is technological development, so that the images of the future illustrate how combinations of planning, behavioural change and technological development could lead to sustainable energy use.

What would a city look like that has reached the aim of sustainable energy use? This paper investigates possible visions of cities and city life that successfully address the climate change challenge. Climate change is caused by excessive emissions of greenhouse gases (GHG). Therefore, targets relating to climate change are often formulated in terms of reductions in GHG. The IPCC assessment of the risk of harmful climate change has led to a recommendation that the mean global temperature must not be allowed to rise by more than 2 °C above pre-industrial levels. The EU climate policy objectives are also based upon the two-degree figure. The EU emissions targets include a 20–30% reduction in GHG emissions by 2020. The Swedish GHG target is a 40% reduction on 1990 levels by 2020 and a vision of 100% reduction (no net emissions of GHG to the atmosphere) by 2050 [2]. There is a close relationship between energy use and GHG emissions, since the use of energy is the cause of most CO2 emissions. However, from a geographical, Sweden-centred perspective, the difference between energy use and CO2 emissions is quite large. Sweden is a sparsely populated country, land is plentiful and there is a large amount of hydropower. Therefore, reducing GHG emissions to a globally sustainable level would be much easier for Sweden as a nation than for most other countries, although it would still be a challenge. However, a world with sustainable use of energy would still need extensive trade in energy. Therefore, in a Swedish context, sustainable use of energy is a tougher criterion than sustainable greenhouse gas emissions. The aim of this paper is to show that future visions of a sustainable city of Stockholm can be fruitfully formulated in terms of spatial and temporal dimensions. The research question is how a combination of spatial city planning and changed use of time can be an effective tool for strategy development towards a transition to a low-energy city, where total energy use by its citizens is sustainable. The paper also aims to show how target-fulfilling backcasting can be used to develop a number of images of the future, thus showing how certain targets could be achieved in different ways. The main justification for a study of this kind is that it can connect short-term and long-term targets, identify potential conflicts between measures needed to achieve various targets, and display the consequences of actually achieving set targets. All these three benefits are very important for developing long-term and short-term policies.

The images of the future presented here are not intended as draft plans, but represent potential ways of changing to low-energy city life. One threat to the feasibility of these images is internal contradictions. For example, the Low-rise Settlements-Fast is somewhat difficult to imagine, as it consists of rich urbanites who choose to live at some distance from the city, but do not use cars a lot. This would probably require a substantial change in norms and values, very tough control measures or a very high cost of driving, but in that case one of the other two urban forms would probably be more attractive. Thus Low-rise Settlement-Fast is an inconsistent image of the future. Energy prices can also render the images unfeasible, as low energy prices are hard to combine with low energy use and high incomes [30]. The only possibility would be an enormous increase in energy efficiency, but such an increase would be unlikely when prices are low. Thus it is difficult to see any of the Fast images of the future in combination with low energy prices. The Fast images might also create strains as the labour market for services grows. Depending on salaries and the cost of services, there is an obvious risk of many new service jobs being low-income jobs, so that services are affordable. This could create social tensions and a lock-in of differences between men and women and between wealthy and poor families. There is also a potential gender trap in the Slow images, namely that the increased share of care and cooking at home would fall on women, while men would get more free time. There are some differences in financial and technological conditions between the urban structures. Little technology is needed to build the Low-rise Settlement structure, and it would require less stringent planning. However, it is likely to lead to a high amount of land conflicts, due to threats to the green wedges. One main barrier to Urban Cores is that huge investment is needed to start building, so any construction company that dares begin might need strong political support. However, once started, the momentum would be strong. The Suburban Centres would probably meet resistance at every point as the new buildings would be inserted into already dense areas. In terms of methodology, this study provides illustrations of low-energy Stockholm and describes the lifestyle changes that might be needed. It also allocates that all energy use to consumption of goods and services by households and shows how some changes that are seen as impossible may be feasible. Presenting images of the future allows deeper analysis of other societal targets that might arise in target fulfilment. A common demand on images of the future and conventional scenarios is that they should be internally consistent. In practice, however, deciding whether a scenario is consistent or not is often a question of belief more than of scientific knowledge. While it is important to clarify parts that might appear inconsistent, such inconsistency is not necessarily a good reason to avoid generating a specific scenario. This study raises at least two more general questions regarding future infrastructure and long-term development. First, in all images described, infrastructure use is very different to that visualised in current long-term planning. Thus, it seems like if climate objectives are to be met, there will have to be changes in some of our most energy-intensive activities, such as air travel and living in large houses. In the 15–50 year perspective this may have strong effects on the demand for infrastructure. Using traditional forecasts as a basis for investment in infrastructure risks leading to very costly investments that society cannot afford to use. Second, there have been attempts, e.g. the Stern report, to calculate the costs of climate change. That report and other general equilibrium models produce results that initially do not resemble those from backcasting studies on sustainable futures. The models often cite a cost for handling climate change of a few percent of GDP, which according to forecasts would postpone increasing wealth by a couple of years, but do not demand major changes in lifestyles and infrastructure. The reasons for these differences need to be further examined. For instance, the GDP in the models might consider production other than that in 2000, so that the changes are hidden, or overlook the fact that transition from now to controlled climate change is economically unfeasible, even if the first and final stages are feasible [30]. Finally, a note on the backcasting method used in this paper. Fig. 7 shows energy use in the scenarios, divided on household function. The most striking thing is that the six columns representing the images look more or less the same, but differ from the 2000 level. This is a result of the starting point that all images of the future had to fulfil the energy reduction target, i.e. add up to the same amount of energy. Some conclusions can be drawn from this. The first is that despite the rather large differences in structure between the scenarios, changes of the same factors tend to be necessary in order to meet the target. The second is that the solutions to these essential factors may be quite different, e.g. low energy use for commuting can be achieved through many different developments. A third, unrelated conclusion concerns the role of technology, which is very important in all scenarios and can reduce energy use by 75% but cannot solve the climate problem on its own.If any one of the five challenges described in previous section would be insurmountable, energy reductions must be even greater within some of the other challenges, or through ways not highlighted here. Since all activities and all energy use are included here, arguing that one challenge is too drastic immediately creates a new discussion regarding other changes necessary. It also allows both technological and behavioural change to be included. The images show that both behavioural and technological change towards energy reduction are needed for the aim of a 60% energy reduction per capita to have any chance of being fulfilled. It is possible that new opportunities arise though e.g. information and communication technologies, or through better knowledge regarding ecosystems and how they are affected by mankind, that could lead to a change in behaviour without changing preferences.