M. Strubegger

Long-term strategies for mitigating global warming

This special issue reviews technological options for mitigating carbon dioxide (CO2) emissions. The options analyzed include efficiency improvements, renewable energies, clean fossil and zero-carbon energy technologies, carbon sequestration and disposal, enhancement of natural carbon sinks (halting deforestation, afforestation, and other sink enhancement options), and geo-engineering measures to compensate for increases in CO2 concentrations. Reduction potentials, costs, and the relative contribution of individual options, as well as their limiting factors and possible timing of introduction and diffusion, are discussed. The study concludes with a discussion of methodological issues and of trade-offs and constraints for implementation strategies to mitigate anthropogenic sources of change in the global carbon cycle.

Energy sector water use implications of a 2 °C climate policy

Quantifying water implications of energy transitions is important for assessing long-term freshwater sustainability since large volumes of water are currently used throughout the energy sector. In this paper, we assess direct global energy sector water use and thermal water pollution across a broad range of energy system transformation pathways to assess water impacts of a 2 °C climate policy. A global integrated assessment model is equipped with the capabilities to account for the water impacts of technologies located throughout the energy supply chain. The model framework is applied across a broad range of 2 °C scenarios to highlight long-term water impact uncertainties over the 21st century. We find that water implications vary significantly across scenarios, and that adaptation in power plant cooling technology can considerably reduce global freshwater withdrawals and thermal pollution. Global freshwater consumption increases across all of the investigated 2 °C scenarios as a result of rapidly expanding electricity demand in developing regions and the prevalence of freshwater-cooled thermal power generation. Reducing energy demand emerges as a robust strategy for water conservation, and enables increased technological flexibility on the supply side to fulfill ambitious climate objectives. The results underscore the importance of an integrated approach when developing water, energy, and climate policy, especially in regions where rapid growth in both energy and water demands is anticipated.

Model-based decision support in energy planning

Models have become standard tools in energy planning. Fast computers and ever improving optimisation packages now allow us to solve problems within a few minutes that were out of range 20 years ago and that 10 years ago could only be solved in several CPU-hours. Fully interactive data bank systems with standardised user interfaces and on-line data access support easy modifications and adaptations of energy models, retrieval and display of results, as well as coupling decision support tools to all kinds of data available in the system. This article gives a brief overview of the objectives in energy planning, especially with respect to different planning horizons. It reviews the types of models applied to different applications and the requirements such tools have to satisfy. The second part surveys some applications of energy optimisation models. These examples have been chosen to illustrate different application areas of energy models from short-term optimal power supply up to very long-term (100 years) resource allocation and technology choice, and from optimising a municipal district heat system up to an energy model for the whole world.

Potential effects of emission taxes on CO2 emissions in the OECD and LDCs

A set of existing optimization models, which represent the energy systems of the OECD and LDCs (less developed countries excluding centrally planned economies) with a time horizon to 2020, has been applied to derive first-order estimates of the techno-economic potential for emission reduction. The driving force for the introduction of reduction measures is a scheme of taxes levied on the emission of six pollutants, including the greenhouse gases CO2 and methane. The tax levels introduced are based on taxes discussed by the Swedish government: they are the break-even point to test which measures are cost-effective and which emission levels can be reached at these costs.

An Approach for Integrated Energy-Economy Decision Analysis The Case of Austria

Many modeling efforts have been undertaken to gain better insight in the interactions between the energy sector and the rest of the economy. One of the first attempts was made with ETA-MACRO [1], consisting of a macro-economic model linked with an energy model, that had its main focus on electricity generation. One of the latest developments in that field is the ZENCAP model [2]. It is based on a multi-sector economy model consisting of an input-output table and a large number of econometrically estimated equations, e.g. for investments, energy demand and employment.

An Integrated Programming Package for Multiple-Criteria Decision Analysis

A number of recent developments (for example, the rapid deterioration of European and North American forests, or the increasing conflict between the trade unions, industrial managers and the government over issues such as unemployment, the national debt, wages, etc.) have highlighted the severe shortcomings of the conventional modeling techniques (e.g., econometric models or technoeconomic approaches) used as a basis for decision making.