Dag Martinsen

From system cost minimization to sustainability maximization—A new fuzzy program approach to energy systems analysis

Abstract The transformation of existing energy systems into sustainable energy systems is a task which is related to several of the most urgent global problems, e.g. security of energy supply, shortage of resources, and climate change. Energy system modeling has played an important role in the computation of optimal possible future energy systems. In particular, technology oriented bottom-up energy system models have given insight into the required evolution of the energy technology mix. In face of the discussion about climate change, energy systems analysis has focused on the calculation of cost minimal energy futures subject to greenhouse gas mitigation paths, especially CO 2 mitigation paths. IKARUS-LP is a model of the German energy system which has been used for optimization tasks of this type. As CO 2 mitigation covers only one facet of sustainability, IKARUS-LP has been enhanced to optimize the German energy system for various sustainability targets specified by energy indicators for sustainable development. The resulting model is a fuzzy linear program, IKARUS-FLP. It computes an optimal compromise between the partly contradictory sustainability targets and system cost minimization. In this paper we introduce this model. Emphasis is given to the derivation of the crisp equivalent of the fuzzy problem. We show that a context-based semantics of fuzzy constraints is not adequate and found our semantics on the fuzzy extension principle. In a real-world case study for a time horizon until 2030 the mitigation path approach of IKARUS-LP and the sustainability optimization approach of IKARUS-FLP are compared. The results prove the feasibility of our new approach and its usefulness.

The System Value of CCS Technologies in the Context of CO2 Mitigation Scenarios for Germany

This chapter analyses the system value of CCS in Germany within the context of consistent greenhouse gas reduction scenarios with and without the implementation of CCS technologies. The system value of CCS is determined using additional CO2 avoidance costs that would occur if climate change mitigation targets were to be met without using CCS even though CCS technology was available. The development of important parameters, assumptions and energy- and climate-policy targets are represented in scenarios. The methodological basis for the scenario calculations is the bottom-up energy system model IKARUS. The energy economics results comprise energy and CO2 balances, capacity development, and the costs of CO2 reduction strategies. From this, the system value of CCS and the contribution of all sectors to it are derived.

IKARUS - A fundamental concept for national GHG-mitigation strategies

Abstract Within the frame of the German IKARUS project a bottom-up energy optimization model and a macroeconomic simulation model based on the input-output approach have been developed. Under the restriction to reduce energy related CO 2 emissions by 25 % until 2005, first model runs have been done for the German Previous States.

The future role of CO2-capture as part of a german mitigation strategy

Publisher Summary This chapter discusses the role that CO2 capture and sequestration (CCS) technologies could play within the scenarios of Germany as a mitigation strategy. As the presentation shows, the use of CCS can represent an interesting mitigation option in view of stringent CO2 reduction goals. The scenarios, performed with the aid of the IKARUS optimization model, however, show that according to cost-efficiency criteria a large number of measures would have to be taken covering all energy sectors. It may be seen that CCS can compete with other mitigation options and in some cases may be more cost-effective. CCS can at best represent one element in an overall strategy. If the existing total power plant capacity in Germany is extrapolated, a considerable number of outdated power plants will have to be replaced in the next 20 years. To make CO2-free power plants available at that time, there is a need to enhance R&D efforts currently in progress. Furthermore, the application of retrofitting measures should also be considered.

Abschätzung der technischen und wirtschaftlichen Potentiale des Beitrags zur Energieversorgung und zur Minderung klimarelevanter Spurengase durch Kernenergie in der Bundesrepublik Deutschland : Studie A.4.2.a und A.4.2.b

In diesem Arbeitspaket A.4.2 werden die Moglichkeiten der Minderung von CO2-Emissionen durch den Einsatz der Kernenergie untersucht. Dabei werden sechs Einsatzbereiche betrachtet, in denen die Kernenergie eine CO2-Emissionsminderung durch Substitution fossiler Energieerzeugung bewirken kann. In Kapitel 2 werden mogliche CO2-Emissionsminderungen im Bereich der Stromerzeugung, in Kapitel 3 bei der Fern- bzw. Nahwarmeerzeugung diskutiert. In den Kapiteln 4 bis 7 werden die CO2-Minderungspotentiale durch die Nutzung der Kernenergie zur Veredelung fossiler Energietrager, zur Prozesdampf- und Prozeswarmeerzeugung, zur Wasserstofferzeugung uber Elektrolyse und bei der tertiaren Erdolforderung in der Bundesrepublik Deutschland untersucht.

Problemstellung und Instrumentarienwahl

Jede Problemlosung bzw. -analyse hat ihren Ursprung in einer Fragestellung. Anhand der gestellten Frage ist das Problem zu definieren. Aus der Fragestellung und der somit erwarteten Antwort sind entsprechend der zu losenden Aufgabe der Losungsweg und damit auch die Hilfsmittel zur Losung jeweils auszuwahlen. Im Kontext dieser Ablauflogik wurde auch das in den folgenden Kapiteln beschriebene Modell „MARNES“entwickelt. In den nachsten Abschnitten soll die Modellentwicklung in den Rahmen der oben skizzierten Ablaufentwicklung eingebettet werden.

Verringerung der CO2-Emissionen — ein Rechenbeispiel

Die Anwendung des vorgestellten Modells sei im folgenden exemplarisch dargestellt. Dabei ist die Fragestellung bewust von aktuellen Problemen gelost, um ein typisches Vorgehen mit der verwendeten Analyseart deutlicher herausstellen zu konnen.

Aussagefähigkeit von Linear-Programming-Modellen

Der Begriff “Modell” wird ublicherweise mit umfangreichen Computermodellen wie beispielsweise dem in diesem Buch beschriebenen MARNESModell gleichgesetzt.