Katja Schumacher

Greenhouse Gas Mitigation in a Carbon Constrained World: The Role of Carbon Capture and Storage

In a carbon constrained world, at least four classes of greenhouse gas mitigation options are available: Energy efficiency, fuel switching, introduction of carbon dioxide capture and storage along with renewable generating technologies, and reductions in emissions of non-CO2 greenhouse gases. The role of energy technologies is considered crucial in climate change mitigation. In particular, carbon capture and storage (CCS) promises to allow for low-emissions fossil-fuel based power generation. The technology is under development; a number of technological, economic, environmental and safety issues remain to be solved. With regard to its sustainability impact, CCS raises a number of questions: On the one hand, CCS may prolong the prevailing coal-to-electricity regime and countervail efforts in other mitigation categories. On the other hand, given the indisputable need to continue using fossil fuels for some time, it may serve as a bridging technology towards a sustainable energy future. In this paper, we discuss the relevant issues for the case of Germany. We provide a survey of the current state of the art of CCS and activities, and perform an energy-environment-economic analysis using a general equilibrium model for Germany. The model analyzes the impact of introducing carbon constraints with respect to the deployment of CCS, to the resulting greenhouse gas emissions, to the energy and technology mix and with respect to interaction of different mitigation efforts. The results show the relative importance of the components in mitigating greenhouse gas emissions in Germany. For example, under the assumption of a CO2 policy, both energy efficiency and CCS will contribute to climate gas mitigation. A given climate target can be achieved at lower marginal costs when the option of CCS is included. We conclude that, given an appropriate legal and policy framework, CCS, energy efficiency and some other mitigation efforts are complementary measures and should form part of a broad mix of measures required for a successful CO2 mitigation strategy.

Bio-electricity and land use in the Future Agricultural Resources Model (FARM)

Bio-electricity is an important technology for Energy Modeling Forum (EMF-27) mitigation scenarios, especially with the possibility of negative carbon dioxide emissions when combined with carbon dioxide capture and storage (CCS). With a strong economic foundation, and broad coverage of economic activity, computable general equilibrium models have proven useful for analysis of alternative climate change policies. However, embedding energy technologies in a general equilibrium model is a challenge, especially for a negative emissions technology with joint products of electricity and carbon dioxide storage. We provide a careful implementation of bio-electricity with CCS in a general equilibrium context, and apply it to selected EMF-27 mitigation scenarios through 2100. Representing bio-electricity and its land requirements requires consideration of competing land uses, including crops, pasture, and forests. Land requirements for bio-electricity start at 200 kilohectares per terawatt-hour declining to approximately 70 kilohectares per terwatt-hour by year 2100 in scenarios with high bioenergy potential.

EUROPEAN-LED CLIMATE POLICY VERSUS GLOBAL MITIGATION ACTION: IMPLICATIONS ON TRADE, TECHNOLOGY, AND ENERGY ¤

This paper examines how changes in an international climate regime would affect the European decarbonization strategy and costs through the mechanisms of trade, technology, and innovation. We present the results from the Energy Modeling Forum (EMF) model comparison study on European climate policy to 2050. Moving from a no-policy scenario to an existing-policies case reduces all energy imports, on average. Introducing a more stringent climate policy target for the EU only leads to slightly greater global emission reductions. Consumers and producers in Europe bear most of the additional burden and inevitably face some economic losses. More ambitious mitigation action outside Europe, especially when paired with a well-operating global carbon market, could reduce the burden for Europe significantly. Because of global learning, the costs of wind and especially solar-PV in Europe would decline below the levels observed in the existing-policy case and increased R&D spending outside the EU would leverage EU R&D investments as well.

Costs of meeting international climate targets without nuclear power

The impact of a global phase-out of nuclear energy is assessed for the costs of meeting international climate policy targets for 2020. The analysis is based on simulations with the Prospective Outlook on Long-term Energy Systems (POLES) global energy systems model. The phase-out of nuclear power increases GHG emissions by 2% globally and 7% for Annex I countries. The price of certificates increases by 24% and total compliance costs of Annex I countries rise by 28%. Compliance costs increase most for Japan (+58%) and the US (+28%). China, India, and Russia benefit from a global nuclear phase-out because revenues from higher trading volumes of certificates outweigh the costs of losing nuclear power as a mitigation option. Even for countries that face a relatively large increase in compliance costs, such as Japan, the nuclear phase-out implies a relatively small overall economic burden. When trading of certificates is available only to countries that committed to a second Kyoto period, the nuclear phase-out results in a larger increase in the compliance costs for the group of Annex I countries (but not for the EU and Australia). Results from sensitivity analyses suggest that the findings are fairly robust to alternative burden-sharing schemes and emission target levels.Policy relevanceNew calculations show that the impact of a global phase-out of nuclear energy on global mitigation costs is quite modest, but that there are substantial differences for countries. Total compliance costs increase the most for Japan and the US, but these are rather marginal if measured in terms of GDP. China, India, and Russia benefit from a nuclear phase-out because their additional revenues from selling certificates outweigh the additional costs of losing nuclear power as a mitigation option. The findings also highlight the importance of certificate trading to achieving climate targets in a cost-efficient way. If Japan or the US were to be banned from certificate trading, along with other countries, because of their non-participation in a second Kyoto period, then their compliance costs would increase substantially under a nuclear phase-out. The EU, however, would benefit because certificate prices would be lower.

Evaluation as a Cornerstone of Policies and Measures for the Energiewende

The German energy transition strategy aims at moving towards a sustainable energy supply and demand over the long term. It consists of many different activities and measures to address existing greenhouse gas mitigation potentials and to mobilize the necessary resources to reach stringent mitigation targets. It builds upon the federal government’s Energy and Climate Programme (BMU 2007) as well as its Energy Concept (BMU & BMWI 2010) and is described in detail in various official documents (BMU & BMWI 2011). The National Climate Initiative (NCI) of the German Federal Ministry for the Environment (BMUB) represents an important element of the programmes and measures relating to the Energiewende. It aims to provide substantial support for the reduction of Germany’s GHG emissions by 40% by 2020 and by 80-95% by 2050 compared to 1990 levels. The NCI is geared to bring about more climate-friendly behavior among businesses, consumers and local authorities in areas with significant efficiency potentials that cannot be tapped by instruments such as the EU Emissions Trading Scheme (the revenues of which fund the NCI). Numerous projects have been developed by the NCI so far, with many others to follow. These projects range from energy-aware and climate-friendly behavior, the use of efficient technologies and renewable energy, to measures