A low-carbon scenario creation method for a local-scale economy and its application in Kyoto city

On May 2008, Kyoto city government set up a low-carbon target of a 50% GHG reduction by 2030 compared to the 1990 level. To contribute to these discussions, we developed a local (city-scale) low-carbon scenario creation method. An estimation model was developed to show a quantitative and consistent future snapshot. The model can explicitly treat the uncertainty of future socio-economic situations, which originate from the openness of local economy. The method was applied to Kyoto city, and countermeasures to achieve the low-carbon target were identified. Without countermeasures, emissions would increase 12% from 2000. Among the measures, the reduction potential of energy efficiency improvements to residential and commercial sectors was found to be relatively large (15% and 18% of total reductions, respectively). The reduction potential of the passenger transport sector, in which the city government's policy is especially important, was 17% of the total amount. A sensitivity analysis showed that a 10% increase in exports leads to an 8.5% increase in CO₂ emissions, and a 20% increase in the share of the commuters from outside the city leads to a 3.5% decrease of CO₂ emissions because of the smaller number of residents in the city.     

Biofuels in the energy transition beyond peak oil.: A macroscopic study of energy demand in the Stockholm transport system 2030

The objective of this study is to examine the potential for a full transition to domestically produced biofuels in the Stockholm County transport system in 2030, without exceeding the proportional share of national bioenergy assets. This target is chosen in order to test the potential of biofuel assets in Sweden, facilitating the transition to renewable fuel systems, and to display the potential of transport energy demand at macrolevel under tighter conditions on the energy market after fossil oil production has peaked. The distribution of bioenergy to the transport sector, including conversion losses and relationships to other energy sectors, is analysed explicitly. State-of-the-art traffic forecasting models, complemented with a specially designed energy quantification model, are applied to assess energy quantities needed at different vehicle efficiency levels and mobility patterns. The purpose is not to determine the most energy-efficient transport system possible, or to forecast the optimal distribution of bioenergy set aside for the transport sector in the future. Rather, we try to visualise, at a more conceptual level, energy demand as dependent on principle transport strategies, future technological developments and a type of planning that takes technological interlinkages between evolving components into strategic account. This work highlights the importance of implementing both demand and supply-side policies in order to reduce energy use and greenhouse gas emissions in all energy sectors before making assessments of reasonable distributions of bioenergy between energy sectors and other biomass usage.     

How much transport can the climate stand?—Sweden on a sustainable path in 2050

In this paper an image of a sustainable transport system for Sweden in 2050 is outlined. The emissions per capita in this image may be generalized to a global population of 9 billions, and still be consistent with a stabilization of the carbon dioxide concentration at 450 ppm (parts per million). Swedish transport energy use per capita is 4.6 MWh in the image, compared to 12.5 MWh at present. The aim is, first, to widen the perspective of sustainable transport futures and, second, to provide a basis for present decisions in areas characterized by a high inertia, e.g. regarding infrastructure and the built-up environment. All transport generated by the lifestyles of Swedish residents are included. The reduction of energy use in the image is primarily achieved by an introduction of energy efficient vehicles and a conscious combination of IT-services and urban planning. The latter aims at increasing functional accessibility while reducing commuting. A prioritization of leisure travel to structurally-enforced travel gives the possibility to increase leisure travel per capita by one third. However, this is contingent on a 50% reduction of per capita car travel in cities. Given the set-up target, it may be concluded that the need for new arterial road capacity in cities often is negligible, even with a considerable population increase.     

Eating energy—Identifying possibilities for reduced energy use in the future food supply system

This paper explores the possibilities for reducing future energy use for eating to a sustainable level. A backcasting approach is used to generate an image of the future where energy use for eating is 60% lower in 2050 than in 2000. The currently known potential to reduce energy use in the food supply system for producing, transporting, storing, cooking and eating food is explored and described in terms of a number of distinct changes that are numbered consecutively and presented in both a quantitative and qualitative way. Sweden is used as the case and all data regarding energy use apply for Swedish conditions. An exercise like this illustrates the possible outcome of taking sustainability seriously. If sustainability is to be achieved, some images of the future are needed so that potential targets can be identified. This paper does not present forecasts, but illustrates the kind of changes needed in order to achieve sustainable energy use in the food system.     

The Tyndall decarbonisation scenarios—Part I: Development of a backcasting methodology with stakeholder participation

The Tyndall decarbonisation scenarios project has outlined alternative pathways whereby a 60% reduction in CO₂ emissions from 1990 levels by 2050, a goal adopted by the UK Government, can be achieved. This paper, Part I of a two part paper, describes the methodology used to develop the scenarios and outlines the motivations for the project. The study utilised a backcasting approach, applied in three phases. In phase one, a set of credible and consistent end-points that described a substantially decarbonised energy system in 2050 were generated and reviewed by stakeholders. In phase two, pathways were developed to achieve the transition to the desired end-point. The impacts of the scenarios were assessed in phase three, by means of a deliberative multi-criteria assessment framework. The scenarios to emerge from this process are elaborated in Part II, and conclusions drawn in relation to the feasibility of achieving the 60% target.     

中国新型城镇化的蓝图构建、实施挑战与研究策略

从城市研究和公共政策分析的角度,讨论了中国新型城镇化的3个基本问题。在发展目标方面,逐一讨论了人口进城与社会建设、经济建设、生态建设、文化建设、政治建设的关系;在实施挑战方面,深入讨论了人口进城落户的规模、结构、效率、质量问题;在研究策略方面,指出中国新型城镇化需要运用回溯比对型方法在愿景与现状之间发现有效的通道和工作空间。     

CO2 emissions from new cars and vehicle weight in Europe; How the EU regulation could have been avoided and how to reach it?

A segment- and fuel-disaggregated analysis of the production data of the new European vehicle market during the last decade helps to understand the sharp increase in average weight, and to introduce an indicator linking CO₂ emissions to a vehicle's unit of weight. Using this indicator, simulations are made to calculate the average CO₂ emissions if the average weight had stayed constant from 1995 to 2005. If the weight had remained constant, the 2008 target of 1998s voluntary agreement (VA) would have been met, and the recently approved regulation would probably have been unnecessary. Then, CO₂ emissions are projected to 2015 using different vehicle characteristics and market penetration. Five scenarios have been introduced to study the different opportunities that could arise by 2015, including a backcasting scenario showing what is needed to reach the goal set by the recently approved EU climate package regulations. The analysis concludes that powertrain technologies alone are unlikely to bring the sufficient break in trends to reach set targets. Acting on average weight, through unitary vehicle weight or segment shifting, of new vehicles is key in reducing the average CO₂ emissions in the short and medium term.     

Towards a sustainable hydrogen economy: A multi-criteria sustainability appraisal of competing hydrogen futures

The ‘hydrogen economy’ has the potential to provide a sustainable and secure energy system, and there is a wide and growing literature promoting and exploring different possible hydrogen futures. However, despite broad agreement that hydrogen could make a significant contribution to energy policy goals, the literature exhibits strong disagreements about the form that a future hydrogen economy should take. Visions of the future select, combine and reconfigure individual hydrogen generation, storage, transport and end-use technologies into more or less mutually compatible energy and transportation systems, which embody deeply contested and conflicting views of sustainability.

This paper describes the application of a novel foresight methodology, which combined participatory scenario development, using a backcasting approach, with an expert-stakeholder multi-criteria mapping (MCM) process, in order to provide an integrated, transparent assessment of the environmental, social and economic sustainability of six possible future hydrogen energy systems for the UK. The findings suggest that: hydrogen has the potential to deliver substantial sustainability benefits over the status quo, or, business as usual, futures, but that hydrogen is not automatically a sustainable option; carbon emissions are the single most important dimension of sustainability, but that issues other than carbon and cost need to be considered if hydrogen is truly to deliver greater sustainability. Furthermore, there was significant disagreement about which visions were considered more or less sustainable. These findings reflect two important sources of divergence in the final sustainability rankings: uncertainties and contested views of sustainability.     

The Tyndall decarbonisation scenarios—Part II: Scenarios for a 60% CO2 reduction in the UK

This paper describes the Tyndall decarbonisation scenarios, the first to take account of CO₂ emissions from the whole of the UK's energy system, including emissions from international shipping and aviation. It builds on Part I, which outlined the backcasting methodology developed to generate the scenarios. The five scenarios produced through this process articulate alternative vision of a substantially decarbonised society in 2050, ranging from a halving of energy consumption from current levels to a near doubling. This work demonstrates that a 60% reduction in the UK's CO₂ emissions is achievable, even when all CO₂ sources are taken into account. The impacts and consequences of the scenarios were assessed by means of a multi-criteria framework which cautions us that the high energy demand scenarios will have a large impact on broader sustainability criteria.     

A backcasting approach for matching regional ecosystem services supply and demand

Ecosystem services (ES) modeling studies typically use a forecasting approach to predict scenarios of future ES provision. Usually, these forecasts do not inform on how specific policy alternatives will influence future ES supply and whether this supply can match ES demand – important information for policy-makers in practice. Addressing these gaps, we present a multi-method backcasting approach that links normative visions with explorative land-use and ES modeling to infer land-use policy strategies for matching regional ES supply and demand. Applied to a case study, the approach develops and evaluates a variety of ES transition pathways and identifies types, combinations and timings of policy interventions that increase ES benefits. By making explicit ES sensitivity towards regional policy strategies and global boundary conditions over time, the approach allows to address key uncertainties involved in ES modeling studies.