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Both focus group discussions and information-choice questionnaires (ICQs) have previously been used to examine informed public opinions about carbon dioxide capture and storage (CCS). This paper presents an extensive experimental study to systematically examine and compare the quality of opinions created by these two research techniques. Depending on experimental condition, participants either participated in a focus group meeting or completed an ICQ. In both conditions participants received identical factual information about two specific CCS options. After having processed the information, they indicated their overall opinion about each CCS option. The quality of these opinions was determined by looking at three outcome-oriented indicators of opinion quality: consistency, stability, and confidence. Results for all three indicators showed that ICQs yielded higher-quality opinions than focus groups, but also that focus groups did not perform poor in this regard. Implications for the choice between focus group discussions and ICQs are discussed.
A number of "roadmapping" activities are being carried out internationally with the aim of planning and facilitating transitions to hydrogen energy systems. However, there is an evident discrepancy between the treatment of quantitative and qualitative information in the majority of roadmapping efforts. Whilst quantitative information is frequently analysed in numerical and computational models, conversely qualitative information tends to be incorporated on a significantly more ad hoc basis. Previous attempts at incorporating qualitative considerations have not usually been systematised. In this paper we present a methodology aimed at increasing the rigour with which qualitative information is treated in hydrogen roadmapping activities. The key changes and actor mapping (KCAM) methodology was developed as the primary qualitative component of the European Hydrogen Energy Roadmap project "HyWays". KCAM, developed from a well known general systems development model, constitutes a means of qualitatively analysing variable hydrogen supply chains that is structured, systematic and flexible.
The establishment of the Leveraging a Climate-neutral Society–strategic Research Network (LCS–RNet) (then named the International Research Network for Low Carbon Societies) was proposed at the Group of Eight (G8) Environment Ministers’ Meeting in 2008. Its 12th annual meeting in December 2021 focused on the discussion on how to transition into a just and sustainable society and how to reduce the risks associated with the transition. This requires comprehensive studies including on the concept of transition, pathways to net-zero societies and how to realise the pathways by collaborating with various stakeholders. This Special Feature provides new insights into sustainability science by linking the scientific knowledge with practical science for the transition through the exploration of studies presented at the annual meeting. Following the opening paper, "A challenge for sustainability science: can we halt climate change?", a wide range of topics were discussed, including practices for sustainable transformation in the Erasmus University, practices in industry, energy transition and international cooperation.
New energy efficiency policies have been introduced around the world. Historically, most energy models were reasonably equipped to assess the impact of classical policies, such as a subsidy or change in taxation. However, these tools are often insufficient to assess the impact of alternative policy instruments. We evaluate the so-called engineering economic models used to assess future industrial energy use. Engineering economic models include the level of detail commonly needed to model the new types of policies considered. We explore approaches to improve the realism and policy relevance of engineering economic modeling frameworks. We also explore solutions to strengthen the policy usefulness of engineering economic analysis that can be built from a framework of multidisciplinary cooperation. The review discusses the main modeling approaches currently used and evaluates the weaknesses in current models. We focus on the needs to further improve the models. We identify research priorities for the modeling framework, technology representation in models, policy evaluation, and modeling of decision-making behavior.
Research on sustainability transitions has expanded rapidly in the last ten years, diversified in terms of topics and geographical applications, and deepened with respect to theories and methods. This article provides an extensive review and an updated research agenda for the field, classified into nine main themes: understanding transitions; power, agency and politics; governing transitions; civil society, culture and social movements; businesses and industries; transitions in practice and everyday life; geography of transitions; ethical aspects; and methodologies. The review shows that the scope of sustainability transitions research has broadened and connections to established disciplines have grown stronger. At the same time, we see that the grand challenges related to sustainability remain unsolved, calling for continued efforts and an acceleration of ongoing transitions. Transition studies can play a key role in this regard by creating new perspectives, approaches and understanding and helping to move society in the direction of sustainability.
Water is a basis for life and ecosystem health. And water, especially in regions affected by water scarcity, is a highly contested and politicised natural resource. The state-of-the-art in sustainable water resources management requires collaborative approaches that foster the integration of conflicting interests of multiple stakeholders. Achieving integration in complex and contested real life situations however remains a major challenge. Boundary work can facilitate this ambitious goal. This study evolves boundary work science to improve collaboration in the water sector. It develops a framework for boundary work that enables understanding, structuring and approaching barriers for collaborative water resources management. A case study from the Garden Route region, South Africa gives a grounded basis for the conceptual developments and further provides in-depth insights into reasons and obstacles for collaborative water resources management in a contested local case. The case study serves both: An intrinsic analysis of a conflictive case, and conceptual developments to the boundary work framework - tested against local realities.
Bridging the data gap
(2004)
Several countries with large coal deposits but limited domestic oil reserves show high interest in coal-to-liquid (CtL) technologies, which could reduce crude oil imports by converting coal into liquid hydrocarbon fuels. After decades of successful large-scale operating experiences in South Africa, CtL activities in the United States, China and Germany have been fanned by the high oil price in the last years. However, CtL indicates negative techno-economic and resource-related features, such as high capital costs, high greenhouse gas discharges and high water consumption. Therefore, the technology's diffusion strongly depends on a favourable framework of policies and strong technology advocates. Daniel Vallentin analyses interdependencies between technical and non-technical parameters affecting the diffusion of CtL technologies in the United States, China and Germany. Applying the inter-disciplinary technological system approach, he identifies factors which determine the market prospects of CtL in these countries, including costs, the geographic distribution of coal reserves, actor constellations and technology, energy and climate policies. At the end of his study, he derives general conclusions with regard to driving forces and barriers for CtL diffusion. As the investigated countries are major consumers of energy and belong to the world's largest emitters of greenhouse gases, their strategies in substituting crude oil based fuels are of utmost global relevance. Therefore, Vallentin's study is recommended to experts, planners, decision-makers, and politicians in the field of climate and resource protection.
For the option of “carbon capture and storage”, an integrated assessment in the form of a life cycle analysis and a cost assessment combined with a systematic comparison with renewable energies regarding future conditions in the power plant market for the situation in Germany is done. The calculations along the whole process chain show that CCS technologies emit per kWh more than generally assumed in clean-coal concepts (total CO2 reduction by 72-90% and total greenhouse gas reduction by 65-79%) and considerable more if compared with renewable electricity. Nevertheless, CCS could lead to a significant absolute reduction of GHG-emissions within the electricity supply system. Furthermore, depending on the growth rates and the market development, renewables could develop faster and could be in the long term cheaper than CCS based plants. Especially, in Germany, CCS as a climate protection option is phasing a specific problem as a huge amount of fossil power plant has to be substituted in the next 15 years where CCS technologies might be not yet available. For a considerable contribution of CCS to climate protection, the energy structure in Germany requires the integration of capture ready plants into the current renewal programs. If CCS retrofit technologies could be applied at least from 2020, this would strongly decrease the expected CO2 emissions and would give a chance to reach the climate protection goal of minus 80% including the renewed fossil-fired power plants.
Development of alternative energy and climate scenarios for the Czech Republic : final report
(2009)
One of the factors decelerating a further diffusion of the carbon capture and storage (CCS) technology is the public's negative perception of early pilot or demonstration activities in Germany as well as in other countries. This study examined the public perception of CCS in more detail by looking into different options within the CCS chain, i.e. for the three elements capture, transport and storage. This was analyzed using an experimental approach, realized in an online survey with a representative German sample of 1830 citizens. Each participant evaluated one of 18 different CCS scenarios created using three types of CO2 source (industry, biomass, coal), two transport options (pipeline vs. no specification), and three storage possibilities (saline aquifer, depleted gas field, enhanced gas recovery (EGR)).
Overall, we found that the ratings of CCS were neutral on average. However, if the CO2 is produced by a biomass power plant or industry, CCS is rated more positively than in a scenario with a coal-fired power plant. The specifications of transport and storage interacted with each other such that scenarios including EGR or a depleted gas field without mentioning a pipeline were evaluated better than storing it in a saline aquifer or a depleted gas field and mentioning a pipeline as means of transport. Exploratory regression analyses indicate the high relevance of the respective CO2 source in general as well as the perceived importance of this source for Germany.
Because of a growing global energy demand and rising oil prices coal-abundant nations, such as China and the United States, are pursuing the application of technologies which could replace crude oil imports by converting coal to synthetic hydrocarbon fuels - so-called coal-to-liquids (CtL) technologies. The case of CtL is well suited to analyse techno-economic, resources-related, policy-driven and actor-related parameters, which are affecting the market prospects of a technology that eases energy security constraints but is hardly compatible with a progressive climate policy. This paper concentrates on Germany as an example - the European Union (EU)'s largest member state with considerable coal reserves. It shows that in Germany and the EU, CtL is facing rather unfavourable market conditions as high costs and ambitious climate targets offset its energy security advantage.
This book presents important new research on applied eco-efficiency concepts throughout Europe. The aim of eco-efficiency is to achieve market-based measures of environmental protection, in order to enhance the prospects for sustainable development and achieve positive economic and ecological benefits. The distinguished authors discuss a number of themes surrounding eco-efficiency including the necessary conditions for technological dissemination and ecological modernization, and the role of government in enabling businesses and society to participate actively in this process. In particular, they highlight the application of existing European-based policies concerning material flows and energy. The authors also investigate some new concepts of sustainable development and provide a useful introduction to material flows analysis. In further chapters they study the emerging regulatory policies for eco-efficiency, and examine the issues of sustainable business and consumption strategies.
For parabolic trough power plants using synthetic oil as the heat transfer medium, the application of solid media sensible heat storage is an attractive option in terms of investment and maintenance costs. One important aspect in storage development is the storage integration into the power plant. A modular operation concept for thermal storage systems was previously suggested by DLR, showing an increase in storage capacity of more than 100 %. However, in these investigations, the additional costs needed to implement this storage concept into the power plant, like for extra piping, valves, pumps and control had not been considered. These aspects are discussed in this paper, showing a decrease of levelized energy costs with modular storage integration of 2 to 3 %. In a Life Cycle Assessment (LCA) a comparison of an AndaSol-I type solar thermal power plant [1] with the original two-tank molten salt storage and with a "hypothetical" concrete storage shows an advantage of the concrete storage technology concerning environmental impacts. The environmental impacts of the “hypothetical” concrete based AndaSol-I decrease by 7 %, considering 1 kWh of solar electricity delivered to the grid. Regarding only the production of the power plant, the emissions decrease by 9.5 %.
Economics beats politics
(2015)
Understanding the diversifying role of civil society in Europe's sustainability pathway is a valid proposition both scientifically and socially. Civil society organisations already play a significant role in the reality of cities, what remains to be explored is the question: what is the role of civil society in the future sustainability of European cities? We first examine the novelty of new forms of civil society organization based on a thorough review of recent case studies of civil society initiatives for sustainable transitions across a diversity of European projects and an extensive literature review. We conceptualize a series of roles that civil society plays and the tensions they entail. We argue that, civil society initiatives can pioneer new social relations and practices therefore be an integral part of urban transformations and can fill the void left by a retreating welfare state, thereby safeguarding and servicing social needs but also backing up such a rolling back of the welfare state. It can act as a hidden innovator - contributing to sustainability but remaining disconnected from the wider society. Assuming each of these roles can have unintended effects, such as being proliferated by political agendas, which endanger its role and social mission, and can be peeled off to serve political agendas resulting in its disempowerment and over-exposure. We conclude with a series of implications for future research on the roles of civil society in urban sustainability transitions.
Energy systems across the globe are going through a radical transformation as a result of technological and institutional changes, depletion of fossil fuel resources, and climate change. At the local level, increasing distributed energy resources requires that the centralized energy systems be re-organized. In this paper, the concept of Integrated community energy systems (ICESs) is presented as a modern development to re-organize local energy systems to integrate distributed energy resources and engage local communities. Local energy systems such as ICESs not only ensure self-provision of energy but also provide essential system services to the larger energy system. In this regard, a comparison of different energy system integration option is provided. We review the current energy trends and the associated technological, socio-economic, environmental and institutional issues shaping the development of ICESs. These systems can be applied to both developed and developing countries, however, their objectives, business models as well as composition differs. ICESs can be accepted by different actors such as local governments, communities, energy suppliers and system operators as an effective means to achieve sustainability and thereby will have significant roles in future energy systems.
Energy and climate change
(2018)
Considering the enormous ecological and economic importance of the transport sector the introduction of alternative fuels - together with drastic energy efficiency gains - will be a key to sustainable mobility, nationally as well as globally. However, the future role of alternative fuels cannot be examined from the isolated perspective of the transport sector. Interactions with the energysystem as a whole have to be taken into account. This holds both for the issue of availability of energy sources as well as for allocation effects, resulting from the shift of renewable energy from the stationary sector to mobile applications. With emphasis on hydrogen as a transport fuel for private passenger cars, this paper discusses the energy systems impacts of various scenarios introducing hydrogen fueled vehicles in Germany. It identifies clear restrictions to an enhanced growth of clean hydrogen production from renewable energy sources (RES). Furthermore, it points at systems interdependencies that call for a priority use of RES electricity in stationary applications. Whereas hydrogen can play an increasing role in transport after 2030 the most important challenge is to exploit short–mid-term potentials of boosting car efficiency.
Insulating existing buildings offers great potential for reducing greenhouse gas emissions and meeting Germany's climate protection targets. Previous research suggests that, since homeowners' decision-making processes are inadequately understood as yet, today's incentives aiming at increasing insulation activity lead to unsatisfactory results. We developed an agent-based model to foster the understanding of homeowners' decision-making processes regarding insulation and to explore how situational factors, such as the structural condition of houses and social interaction, influence their insulation activity. Simulation experiments allow us furthermore to study the influence of socio-spatial structures such as residential segregation and population density on the diffusion of renovation behavior among homeowners. Based on the insights gained, we derive recommendations for designing innovative policy instruments. We conclude that the success of particular policy instruments aiming at increasing homeowners' insulation activity in a specific region depends on the socio-spatial structure at hand, and that reducing financial constraints only has a relatively low potential for increasing Germany's insulation rate. Policy instruments should also target the fact that specific renovation occasions are used to undertake additional insulation activities, e.g. by incentivizing lenders and craftsmen to advise homeowners to have insulation installed.
In the Paris Accord to the UN Climate Change Conference COP21 in 2015, the international community agreed to "make every effort" to reach a significant reduction in greenhouse gas (GHG) emissions and to limit global average temperature rise to preferably 1.5°C by 2100 (UNFCC 2018). A transition to a climate-friendly energy supply, however, would come largely at the expense of coal - a fossil fuel with large global reserves that are also widely dispersed regionally. Therefore, especially since the turn of the millennium, the question has been raised as to how coal could be used in a climate-friendly way in the future. So far, the only way to do this is to apply CCS technology or CCU. CCS involves the capture of carbon dioxide (CO2) emissions from fossil fuel-fired power plants or industrial sources and its storage underground, such as in deep saline aquifers or in depleted oil and natural gas fields, or their use for enhanced oil or gas recovery (EOR/EGR). When carbon capture and utilisation (CCU) is applied, the CO2 is further used, for example as feedstock for the production of durable plastics. Due to the relatively low potential of CCU compared to CCS (IPCC 2005), only CCS is considered in this thesis.
The majority of studies and roadmaps have discussed CCS as a technology option that could make a significant contribution to achieving the objective of decreasing GHG emissions for many years (IPCC 2014a, 2018). Particularly in the power sector, however, these expectations have not yet been met. As of November 2019, worldwide only two small base-load power plants, capturing a total of 2.4 Mt CO2/year and mainly using it for EOR, are in operation, together with a few pilots in industrial applications and, in particular, natural gas processing (in total 30 Mt CO2/year) (Global CCS Institute 2019).
Early on, it became clear that the predicted high deployment targets and their underlying studies should be critically questioned for various reasons. Particularly due to the lack of a systems-analytical evaluation of this technology (which was relatively new at the time), no reliable answers could be given about the ecological, economic, social and structural effects of its large-scale application. Such analyses are, however, a pre-condition for comprehensively classifying the contribution of a new technology as a promising option for a sustainable energy supply system and assessing it in comparison to other technologies.
To address these challenges, several studies, most of which initiated by the author, were conducted on this topic between 2004 and 2018. The resulting papers became the basis for this thesis.
This study provides insight into the feasibility of a CO2 trunkline from the Netherlands to the Utsira formation in the Norwegian part of the North Sea, which is a large geological storage reservoir for CO2. The feasibility is investigated in competition with CO2 storage in onshore and near-offshore sinks in the Netherlands. Least-cost modelling with a MARKAL model in combination with ArcGIS was used to assess the cost-effectiveness of the trunkline as part of aDutch greenhouse gas emission reduction strategy for the Dutch electricity sector and CO2 intensive industry. The results show that under the condition that a CO2 permit price increases from €25 per tCO2 in 2010 to €60 per tCO2 in 2030, and remains at this level up to 2050, CO2 emissions in the Netherlands could reduce with 67% in 2050 compared to 1990, and investment in the Utsira trunkline may be cost-effective from 2020–2030 provided that Belgian and German CO2 is transported and stored via the Netherlands as well. In this case, by 2050 more than 2.1 GtCO2 would have been transported from the Netherlands to the Utsira formation. However, if the Utsira trunkline is not used for transportation of CO2 from Belgium and Germany, it may become cost-effective 10 years later, and less than 1.3 GtCO2 from the Netherlands would have been stored in the Utsiraformation by 2050. On the short term, CO2 storage in Dutch fields appears more cost-effective than in the Utsira formation, but as yet there are major uncertainties related to the timing and effective exploitation of the Dutch offshore storage opportunities.
The paper analyzes a Bolivian region for possible cultivation of the oil plant Jatropha curcas for sustainable biodiesel production in order to replace in part Bolivia's diesel imports. The specific site for this study is located in the dry region of Gran Chaco in Santa Cruz. The aim of this work is to analyse the potential of useable land and resources for sustainable biodiesel production from Jatropha without competition with edibles production using economic, environmental and social criteria. In addition the article introduces Jatropha as one of the preferred oil plants for biodiesel production in several countries and indicates its different uses. The recommendation to cultivate Jatropha for biodiesel production is based on an exploration of the possibility of land use in the selected region and the benefits Jatropha production could offer. In this manner a sustainable cultivation of Jatropha in the region of Gran Chaco is recommended to produce biodiesel and to improve some of the environmental problems facing the region.
Natural gas makes an increasing contribution to the European Union's energy supply. Due to its efficiency and low level of combustion emissions this reduces greenhouse gas emissions compared to the use of other fossil fuels. However, being itself a potent greenhouse gas, a high level of direct losses of natural gas in its process chain could neutralise these advantages. Which effect will finally prevail depends on future economical as well as technical developments. Based on two different scenarios of the main influencing factors we can conclude that over the next two decades CH4 emissions from the natural gas supply chain can be significantly reduced, in spite of unfavourable developments of the supply structures. This, however, needs a substantial, but economically attractive investment into new technology, particularly in Russia.
Future of car-sharing in Germany : customer potential estimation, diffusion and ecological effect
(2007)
The global land area required to meet the German consumption of agricultural products for food and non-food use was quantified, and the related greenhouse gas (GHG) emissions, particularly those induced by land-use changes in tropical countries, were estimated. Two comprehensive business-as-usual scenarios describe the development corridor of biomass for non-food use in terms of energetic and non-energetic purposes. In terms of land use, Germany was already a net importer of agricultural land in 2004, and the net additional land required by 2030 is estimated to comprise 2.5–3.4 Mha. This is mainly due to biofuel demand driven by current policy targets. Meeting the required biodiesel import demand would result in an additional GWP of 23–37 Tg of CO2 equivalents through direct and indirect land-use changes. Alternative scenario elements outline the potential options for reducing Germany's land requirement, which reflect future global per capita availability.
Biogas and bio-methane that are based on energy crops are renewable energy carriers and therefore potentially contribute to climate protection. However, significant greenhouse gas emissions resulting from agricultural production processes must be considered, mainly resulting from agricultural production processes, as fertilizer use, pesticide etc.
This paper provides an integrated life cycle assessment (LCA) of biogas (i.e. bio-methane that has been upgraded and injected into the natural gas grid), taking into account the processes of fermentation, upgrading and injection to the grid for two different types of biogas plants thus examining the current state of the art as well as new, large-scale plants, operated by industrial players. Not only technical and engineering aspects are taken into account here, but also the choice of feedstock which plays an important role as to the overall ecological evaluation of bio-methane.
The substrates evaluated in this paper - aside from maize - are rye, sorghum, whole-crop-silage from triticale and barley, and the innovative options of agricultural grass (Landsberger Gemenge, a mixture of hairy vetch (vicia villosa), crimson clover (trifolium incarnátum) and Italian ryegrass (lolium multiflorum)) as well as a combination of maize and sunflower.
How much is 100 billion US dollars? : Climate finance between adequacy and creative accounting
(2011)
Impacts of energy use on demand for freight transport : past development and future perspectives
(2005)
How is it possible to increase homeowners' insulation activity? Answering this question is key to successful policies regarding energy-efficient buildings worldwide. In Germany, doubling today's insulation rate of about 1% is an important element for reaching the government's target of an 80% reduction in energy demand in the building sector by 2050.
This thesis uses an agent-based model analysis to improve the understanding of homeowners' insulation activity and to explore new approaches aiming at its increase in Germany. Two agent-based models were developed and utilized. The first model was developed mainly based on insights derived from a structured literature review. The second emerged from the previous one, incorporating the results of an online survey conducted among 275 homeowners.
The results indicate that homeowners' economic means have little influence on their decision to install insulation. Instead, their insulation decision-making is mostly affected by situational factors and their attitudes towards insulation. Situational factors, such as the condition of the building, are important because they initiate homeowners' individual decision-making processes on insulation. The simulation results show that improving homeowners’ attitudes about insulation by providing information has a comparatively low potential for increasing their insulation activity. Out of the policy options this thesis explored, the introduction of an obligation to insulate the walls within one year after change of house ownership was found to have the greatest impact on homeowners' insulation activity.
Industry
(2014)
Innovation and diffusion of car-sharing for sustainable consumption and production of urban mobility
(2008)
Integrated systems analysis
(2007)
The North African countries Morocco, Algeria, Tunisia, Libya and Egypt have been and are currently experiencing rapid growth in energy demand. This development confronts their political leaders with the question of how to expand or diversify their countries' generation capacities. In this context, renewable energies and nuclear power constitute options that have rarely been exploited so far in the region. This article analyzes the drawbacks and benefits of both alternatives, with a special focus on import and export dynamics. When attempting to make the strategic decision between renewables and atomic power, North African regional specifics and circumstances have to be taken into account. Hence, in a first step, the article characterizes the energy systems of the North African countries and presents scenarios for their future development. In a second step, it scrutinizes the energy challenges these states face in terms of domestic concerns and foreign affairs. Finally, a case study of Algeria is used to demonstrate how renewable energies, but not nuclear power, are able to respond to North African energy challenges.
Energy system optimization models (ESOMs) such as MARKAL/TIMES are used to support energy policy analysis worldwide. ESOMs cover the full life-cycle of fuels from extraction to end-use, including the associated direct emissions. Nevertheless, the life-cycle emissions of energy equipment and infrastructure are not modelled explicitly. This prevents analysis of questions relating to the relative importance of emissions associated with the build-up of infrastructure and other equipment required for decarbonization.
Iran as an energy-rich country faces many challenges in optimal utilization of its vast resources. High population and economic growth, generous subsidies program, and poor resource management have contributed to rapidly growing energy consumption and high energy intensity for the past decades. The continuing trend of energy consumption will bring about new challenges as it will shrink oil exports revenues restraining economic activities and lowering standard of living. This study intends to tackle some of the important challenges in the energy sector and to explore alternative scenarios for utilization of energy resources in Iran for the period 2005-2030. We use techo-economic or end-use approach along with econometric methods to model energy demand in Iran for different types (fuel, natural gas, electricity, and renewable energy) in all sectors of the economy (household, industry, transport, power plants, and others) and forecast it under three scenarios: Business As Usual (BAU), Efficiency, and Renewable Energy.
This study is the first comprehensive study that models the Iranian energy demand using the data at different aggregation levels and a combination of methods to illuminate the future of energy demand under alternative scenarios. The results of the study have great policy implications as they indicate a huge potential for energy conservation and therefore additional revenues and emission reduction under the efficiency scenario compared with the base scenario. Specifically, the total final energy demand under the BAU scenario will grow on average by 2.6 percent per year reaching twice the level as that in 2005. In contrast, the total final energy demand in the Efficiency scenario will only grow by 0.4 percent on average per year. The average growth of energy demand under the combined Efficiency and Renewable Energy scenarios will be 0.2 percent per year. In the BAU scenario, energy intensity will be reduced by about 30 percent by 2030, but will still be above today's world average. In the Efficiency scenario, however, energy intensity will decline by about 60 percent by 2030 to a level lower than the world average today. The energy savings under the Efficiency and Renewable scenarios will generate significant additional revenues and will lead to 45 percent reduction in CO2-emissions by 2030 as compared to the BAU trends.
Using natural gas for fuel releases less carbon dioxide per unit of energy produced than burning oil or coal, but its production and transport are accompanied by emissions of methane, which is a much more potent greenhouse gas than carbon dioxide in the short term. This calls into question whether climate forcing could be reduced by switching from coal and oil to natural gas. We have made measurements in Russia along the world's largest gas-transport system and find that methane leakage is in the region of 1.4%, which is considerably less than expected and comparable to that from systems in the United States. Our calculations indicate that using natural gas in preference to other fossil fuels could be useful in the short term for mitigating climate change.