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It is expected that end-users from all sectors should participate in providing system flexibility, as variable renewable energy is increasingly integrated into electricity systems. The ability of end-users to shift their electricity profiles has considerable potentials and can serve many purposes, e.g. to curb the peak load or to increase self-consumption. However, evaluation methods designed for flexibility from conventional power plants may be inadequate for flexibility from end-users due to the diverse constraints of underlying processes and limitations related to individual needs. This work presents a comprehensive and modular flexibility model developed from common operational characteristics of flexible processes as an alternativemethod. The model is applied to two examples: First, the operation of a combined heat-and-power plant including input and output storage is optimized with the objective to increase profits from electricity sales on the spot market. Second, a steel rod production line consisting of melting, casting, and milling processes is scheduled so that operating costs, including peak power costs, are minimized. Moreover, potentials of flexibility as external services and related costs are analysed. In this paper, the model is used to calculate the optimal costs (e), time-dependent flexibility potentials (kWh) and costs of flexibility provision (e/kWh). Thus, the adaptability and versatility of the model are demonstrated. As a modelling template, the model can ease the efforts of stakeholders in the characterization and evaluation of various flexible processes, especially those from small and medium-sized users.

Der Abschlussbericht stellt die Ergebnisse der mehrjährigen Arbeit im Wärme-Schwerpunkt des ENavi-Projektes vor. Im Zuge der Tätigkeiten wurden Hemmnisse für Klimaschutz im Wärmesektor identifiziert, politische Maßnahmen zur Beschleunigung der Transformation definiert, deren Folgen szenario-basiert abgeschätzt und wissenschaftlich sowie diskursiv mit Stakeholdern anhand eines Kriterienkataloges bewertet. Dadurch ist der Bericht sowohl in der Transformationsforschung als auch in der transformativen Forschung hin zu einer nachhaltigen Energieversorgung angesiedelt.

Mit der sogenannten Sektorkopplung will die Bundesregierung den Einsatz von fossilen Energien reduzieren: Erneuerbare Energien sollen nicht mehr nur für den Stromsektor eingesetzt werden, sondern auch in den Sektoren Verkehr, Wärme und Industrie. Forscher(innen) des Kopernikus-Projekts Energiewende-Navigationssystem (ENavi) untersuchen, wie sich die Nachfrage nach Strom flexibel gestalten lässt.

29th European Photovoltaic Solar Energy Conference and Exhibition; 3886-3893, This paper examines possible operating options of a grid-connected hybrid energy system (HES), including a photovoltaic (PV) system. Different technologies are examined, including fluctuating renewable energy sources (RES), especially PV and wind power, electrical energy storage (EES) and a biomass power plant. The aim of the work is to illustrate an optimal system design in combination with a most cost-effective operation of such a power plant. An existing optimization model is extended in order to analyse the operation and design of a hybrid energy system. The system design and operation is optimized under technical, economic and regulatory constraints within a single model. This optimization model is able to provide a market-oriented operation of the hybrid system under the consideration of energy demand, renewable energy resources and achieved market prices. The paper focuses on the cost-efficient electrical supply of an industrial company by the optional use of renewable energy sources at a location in Germany. Various scenarios are analysed to better define the properties and the sensitivity of the model. Thus, effects of external technical and economic conditions, such as variable market prices or fixed self-consumption, are examined for plant operation and system design. With the help of this work, it is shown under which conditions the investment in a HES with RES for an industrial company is optimal and how such a hybrid plant would be operated in the ideal case.

29th European Photovoltaic Solar Energy Conference and Exhibition; 4086-4090, This paper presents the findings of the Fraunhofer ISE study on the levelized cost of electricity (LCOE) of renewable energy technologies with a focus on PV (Fraunhofer ISE, 2013). It predicts future cost and market developments through 2030 based on technology-specific learning curves and market scenarios. Photovoltaics (PV) are assessed in Germany. Moreover, the solar technologies PV and concentrating photovoltaics (CPV) are analyzed in regions with higher solar irradiation. They are compared to other renewable energy technologies such as (onshore and offshore) wind power, concentrating solar power (CSP) and biogas on the basis of common market financing costs. The current and future LCOE for new conventional power plants (brown coal, hard coal, combined cycle gas turbine (CCGT), oil-fired power plants) are calculated as a reference.

Die Stromgestehungskosten von erneuerbaren Energien sind stark gesunken und nähern sich denen fossiler Energien an. Bis zum Jahr 2030 wird Strom aus Photovoltaik (PV)- und Windkraftanlagen sogar billiger als Strom aus fossilen Kraftwerken sein, wie eine aktuelle Studie des Fraunhofer-Instituts für Solare Energiesysteme ISE belegt. Selbst kleine PV-Aufdachanlagen in Norddeutschland produzieren schon heute sauberen Strom zu Kosten unterhalb des durchschnittlichen Haushaltsstrompreises. Wind und Sonne werden in der Zukunft den günstigsten Strom liefern.

27th European Photovoltaic Solar Energy Conference and Exhibition; 4753-4756, This paper evaluates the barriers and obstacles when developing new PV production facilities for cells, modules, inverters and other balance of systems (BOS) components as well as implementing PV power plants in emerging markets. These often present a more difficult business and regulatory framework compared to the wellknown established solar markets. Based on a case study for Morocco within the context of the Moroccan Solar Plan (MSP), the central key issues and main decision criteria for the evaluation of potential production facilities or new PV power plants are identified. Constraints like legal barriers, local market developments, economic attractiveness, investment climate hinder the investment in the Moroccan PV market of international as well as local companies. Moreover, the market size and the export possibilities are further essential decision criteria. For the implementation of PV power plants in emerging markets, an easy authorization process, a guaranteed grid connection and local suppliers were identified as main influence factors concerning the project success. The analysis of the status-quo, potential barriers and possible strategies helps PV companies to understand the market demand and to overcome entrance difficulties. As local service providers for the grid connection and power plant installation are on the edge of starting new solar activities in emerging markets, international project developers and installers have to analysis potential local suppliers carefully.

Plants produce nectar in their flowers as a reward for their pollinators and most of our crops depend on insect pollination, but little is known on the physiological control of nectar secretion. Jasmonates are well-known for their effects on senescence, the development and opening of flowers and on plant defences such as extrafloral nectar. Their role in floral nectar secretion has, however, not been explored so far. We investigated whether jasmonates have an influence on floral nectar secretion in oil-seed rape, Brassica napus. The floral tissues of this plant produced jasmonic acid (JA) endogenously, and JA concentrations peaked shortly before nectar secretion was highest. Exogenous application of JA to flowers induced nectar secretion, which was suppressed by treatment with phenidone, an inhibitor of JA synthesis. This effect could be reversed by additional application of JA. Jasmonoyl-isoleucine and its structural mimic coronalon also increased nectar secretion. Herbivory or addition of JA to the leaves did not have an effect on floral nectar secretion, demonstrating a functional separation of systemic defence signalling from reproductive nectar secretion. Jasmonates, which have been intensively studied in the context of herbivore defences and flower development, have a profound effect on floral nectar secretion and, thus, pollination efficiency in B. napus. Our results link floral nectar secretion to jasmonate signalling and thereby integrate the floral nectar secretion into the complex network of oxylipid-mediated developmental processes of plants.