Die deutsche Energiewende ist eingeleitet, doch droht das Projekt ins Stocken zu geraten, wenn die Zuständigkeiten nicht geklärt werden. Da der Energiemarkt allein den Umbau der Energieversorgung nicht stemmen kann, ist die Politik gefordert. Neben dem weiteren Ausbau von erneuerbaren Energien gilt es, Energieeffizienzmaßnahmen zu forcieren und das Potenzial des Energiesparens auszuschöpfen. Energieanbieter müssen verpflichtet werden, bei der Zielerfüllung eine konstruktivere Rolle zu spielen als bisher.
Stabilizing the concentration of greenhouse gases (GHGs) in the atmosphere at levels compatible with sustainable development is the objective of the United Nations Framework Convention on Climate Change (UNFCCC) and an imperative for the global community. This is a daunting task, and its magnitude and costs are debated among scientists as well as policy-makers [Stern, 2006]. While most GHGs in the past have been emitted by developed countries and they are called upon to reduce their emissions and take responsibility for past mistakes, the contribution of developing countries in the future will reach similar magnitudes and is equally threatening for life on this planet. While developing countries have no commitments under the UNFCCC, they can still contribute voluntarily to climate change mitigation. The Global Environment Facility (GEF), as the financial mechanism of the UNFCCC and the leading multilateral entity promoting energy efficiency and renewable energy in developing countries and countries in transition, needs to provide significant support to these countries with respect to reaching a path of sustainable energy supply and sustainable economic and social development. Since 1992, the GEF has provided around US$ 2 billion in grants to support projects in the climate change focal area, leveraging over US$ 10 billion in total investments. Most of these funds have been spent on climate change mitigation projects. The GEF's mandate with respect to mitigation is to develop, expand, and transform markets for energy and mobility in developing countries, enabling them to grow toward and efficiently operate on a less carbon-intensive path. In doing so, the GEF applies the incremental cost principle and is restricted in the selection of technologies by a number of factors. Developing markets for sustainable energy technologies and sustainable framework conditions is a long-term effort, and it is hard to understand how effective the GEF is or can be in fulfilling this mission. This paper discusses the magnitude of the challenge, and demonstrates that this challenge is too big for the GEF's limited funds, and provides some suggestions for the GEF's programming for maximizing its impact on global GHG emissions by seeking out the most rewarding opportunities and maximizing replication of successful project examples by effective outreach and knowledge management.
The role of hydrogen in long run sustainable energy scenarios for the world and for the case of Germany is analysed, based on key criteria for sustainable energy systems. The possible range of hydrogen within long-term energy scenarios is broad and uncertain depending on assumptions on used primary energy, technology mix, rate of energy efficiency increase and costs degression ("learning effects"). In any case, sustainable energy strategies must give energy efficiency highest priority combined with an accelerated market introduction of renewables ("integrated strategy"). Under these conditions hydrogen will play a major role not before 2030 using natural gas as a bridge to renewable hydrogen. Against the background of an ambitious CO2-reduction goal which is under discussion in Germany the potentials for efficiency increase, the necessary structural change of the power plant system (corresponding to the decision to phase out nuclear energy, the transformation of the transportation sector and the market implementation order of renewable energies ("following efficiency guidelines first for electricity generation purposes, than for heat generation and than for the transportation sector")) are analysed based on latest sustainable energy scenarios.
Within one decade a fundamental choice will have to be made: Should the energy system follow the historical trends of risky and unsustainable energy use patterns? Or should it take the course towards sustainable development and climate protection, giving top priority to energy efficiency and to a broad mix of renewable energies? Both roads are technically feasible. "Back-casting"-scenarios could help to answer the question, what technological options are available for climate protection and how societal goals can be achieved in a cost-effective way. Lessons learned from world energy scenarios and possible implementation options will be discussed. A case study of the German Parliament ́s Enquete Commission on Sustainable Energy Systems will be taken as illustration. The analysis shows that sustainable energy systems can be financed and that economic growth can be decoupled from absolute levels of non-renewable energy consumption by stepping up energy productivity.
In February 2000, the German Bundestag established a Study Commission on "Sustainable Energy Supplies in View of Globalisation and Liberalisation" (cf. Final Report, 2002). The Commission's Final Report is a contribution made by Germany toward implementing the sustainable development objectives defined in 1992 at the World Summit in Rio de Janeiro (Agenda 21). Despite minority votes of several members of the Study Commission, the main outcomes of the Final Report are worthwhile discussing in other industrial countries. The Commission had been given the mandate to identify "robust, sustainable development paths" for the energy sector for the period up to 2050, which represent a scientific basis for the German parliament's further decision-making in the field of long-term energy policy. The applied backcasting approach showed that an ambitious climate-protection goal - reducing CO2 emissions by 80% by 2050 - is technically and economically feasible. The main strategies and instruments for protecting the climate while ensuring asustainable energy supply are summarised.