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Nach wie vor wird intensiv über die Einführung und Etablierung erneuerbarer Energien zur klimaneutralen Deckung der Energienachfrage diskutiert. Eine wesentliche Option ist hier die Biomasse, die bereits heute z. T. erheblich zur Deckung der Energienachfrage im globalen Energiesystem beiträgt. Deshalb werden nachfolgend die heutigen und zukünftigen weltweiten Bioenergiepotenziale untersucht und der entsprechenden Nutzung gegenüber gestellt. Dabei zeigt sich u. a., dass der Anteil, den die Biomasse zur Wärme-, Strom- und Kraftstofferzeugung weltweit beiträgt, zwar bis 2030 absolut ansteigen wird, die zur Energieerzeugung verfügbare Biomasse jedoch insgesamt tendenziell abnehmen dürfte.The introduction and establishment of renewable energies is still discussed intensively with the focus on climate-neutral coverage of the global energy demand. In this regard it is a valid option to use biomass as a feedstock. Already today biomass contributes significantly to cover the energy demand in the global energy system. Therefore, the present and future global bioenergy potentials are investigated in the following and compared to the respective biomass use. The results show, amongst others, that the share of biomass for heat, electricity and fuel production will increase worldwide until 2030, although the availability of biomass for energy production is likely to decline in the future.

Heating and cooling in buildings, businesses and industry consume around half of the energy produced and used in the European Union. Most heat is required in residential sector 45%, but also the industrial sector and service sector represent with 37% and 18% a significant share. Round about 90% [1] of the heat is produced based on fossil energy sources, which led to a dramatically increase in greenhouse gas emissions on the past decades. Bioenergy could contribute to the decarbonisation and so to achieve the climate targets of the EU. Thus solid biomass is one alternative to satisfy the European heat demand, but so far the utilization of this renewable for heat purposes in the business sector is under-represented. European project Bioenergy4Business, supported by the European Framework Program HORIZON 2020, has the main objective to increase the use of solid biomass sources for heat purposes in the commercial sector in the 11 participating countries across the EU. Existent barriers hindering the increased use of solid bioenergy and possible approaches to overcome them were identified by conducting stakeholder interviews and expert discussions on organized workshops. Main result of the research are the identification of barriers and first approaches to overcome them and finally to increase a co-operation between stakeholders from the demand and supply side as well as policy makers to create an appropriate legal framework and/or promotion conditions. There are still a lot of barriers and uncertainties regarding the usage of solid biomass in the promising market segments. A close co-operation of stakeholders from the demand and supply side as well as policy maker is crucial to create an appropriate legal framework and/or promotions conditions. Also a successful education program removing the existing gaps of knowledge is necessary and can only be elaborated by concerted action of the EU Member States.

Optical transport layers need rearrangeable wavelength-division multiplexing optical cross-connects (OXCs) to increase the capacity and flexibility of the network. It has previously been shown that a cross-connect based on all-optical wavelength converters for routing as well as wavelength slot interchanging can be used to create a robust and nonblocking OXC. However, for an OXC with n fiber inlets each carrying m wavelengths the OXC requires n×m internal wavelengths, which constrains the size of the cross-connect. In this paper we therefore propose and demonstrate an architecture that uses a reduced set of internal wavelengths without sacrificing cross-connecting capabilities. By inserting a partly equipped OXC with the new architecture in a 10-Gbit/s re-circulating loop setup we demonstrate the possibility of cascading up to ten OXCs. Furthermore, we investigate the regenerating effect of the OXC on signals that suffer from interferometric crosstalk

An interferometric Michelson wavelength converter is presented that combines a speed-optimized semiconductor optical amplifier technology with the benefits of the integrated interferometer showing 40-Gbit/s wavelength conversion. The optimized wavelength converter demonstrates noninverted converted signals as well as converts to both shorter and longer wavelengths. Excellent results are achieved with ~10 dB extinction ratio and more than 25 dB signal-to-ASE (amplified spontaneous emission) ratio (1 nm) for the converted signals at 40 Gbit/s

This work assesses the prospects for high-speed all-optical wavelength conversion using the simple optical interaction with the gain in semiconductor optical amplifiers (SOAs) via the interband carrier recombination. Operation and design guidelines for conversion speeds above 10 Gb/s are described and the various tradeoffs are discussed. Experiments at bit rates up to 40 Gb/s are presented for both cross-gain modulation (XGM) and cross-phase modulation (XPM) in SOAs demonstrating the high-speed capability of these techniques