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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.
Because of a growing dependence on oil imports, powerful industrial, political and societal stakeholders in the UnitedStates are trying to enhance national energy security through the conversion of domestic coal into synthetic hydrocarbon liquid fuels - so-called coal-to-liquids (CtL) processes. However, because of the technology's high costs and carbon intensity, its market deployment is strongly affected by the US energy, technology and climate policy setting. This paper analyses and discusses policy drivers and barriers for CtL technologies in the United States and reaches the conclusion that an increasing awareness of global warming among US policy-makers raises the requirements for the technology's environmental performance and, thus, limits its potential to regional niche markets in coal-producing states or strategic markets, such as the military, with specific security and fuel requirements.
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.
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.
Scenarios for the future of renewable energy through 2050 are reviewed to explore how much renewable energy is considered possible or desirable and to inform policymaking. Existing policy targets for 2010 and 2020 are also reviewed for comparison. Common indicators are shares of primary energy, electricity, heat, and transport fuels from renewables. Global, Europe-wide, and country-specific scenarios show 10% to 50% shares of primary energy from renewables by 2050. By 2020, many targets and scenarios show 20% to 35% share of electricity from renewables, increasing to the range 50% to 80% by 2050 under the highest scenarios. Carbon-constrained scenarios for stabilization of emissions or atmospheric concentration depict trade-offs between renewables, nuclear power, and carbon capture and storage (CCS) from coal, most with high energy efficiency. Scenario outcomes differ depending on degree of future policy action, fuel prices, carbon prices, technology cost reductions, and aggregate energy demand, with resource constraints mainly for biomass and biofuels.
The Russian natural gas industry is the world's largest producer and transporter of natural gas. This paper aims to characterize the methane emissions from Russian natural gas transmission operations, to explain projects to reduce these emissions, and to characterize the role of emissions reduction within the context of current GHG policy. It draws on the most recent independent measurements at all parts of the Russian long distance transport system made by the Wuppertal Institute in 2003 and combines these results with the findings from the US Natural Gas STAR Program on GHG mitigation options and economics.
With this background the paper concludes that the methane emissions from the Russian natural gas long distance network are approximately 0.6% of the natural gas delivered. Mitigating these emissions can create new revenue streams for the operator in the form of reduced costs, increased gas throughput and sales, and earned carbon credits. Specific emissions sources that have cost-effective mitigation solutions are also opportunities for outside investment for the Joint Implementation Kyoto Protocol flexibility mechanism or other carbon markets.
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.
Because of high efficiency, low environmental impacts and a potential role in transforming our energy system into a hydrogen economy, fuel cells are often considered as a key technology for a sustainable energy supply. However, the future framing conditions under which stationary fuel cells have to prove their technical and economic competitiveness are most likely characterised by a reduced demand for space heating, and a growing contribution of renewable energy sources to heat and electricity supply, which both directly limit the potential for combined heat and power generation, and thus also for fuelcells. Taking Germany as a case study, this paper explores the market potential of stationaryfuelcells under the structural changes of the energy demand and supply system required to achieve asustainable energy supply. Results indicate that among the scenarios analysed it is in particular a strategy oriented towards ambitious CO2-reduction targets, which due to its changes in the supply structure is in a position to mobilise a market potential that might be large enough for a successful fuel cell commercialisation. However, under the conditions of a business-as-usual trajectory the sales targets of fuel cell manufacturers cannot be met.