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AbstractClimate change and land‐use change are two major drivers of biome shifts causing habitat and biodiversity loss. What is missing is a continental‐scale future projection of the estimated relative impacts of both drivers on biome shifts over the course of this century. Here, we provide such a projection for the biodiverse region of Latin America under four socio‐economic development scenarios. We find that across all scenarios 5–6% of the total area will undergo biome shifts that can be attributed to climate change until 2099. The relative impact of climate change on biome shifts may overtake land‐use change even under an optimistic climate scenario, if land‐use expansion is halted by the mid‐century. We suggest that constraining land‐use change and preserving the remaining natural vegetation early during this century creates opportunities to mitigate climate‐change impacts during the second half of this century. Our results may guide the evaluation of socio‐economic scenarios in terms of their potential for biome conservation under global change.

Through a parametric time-series analysis of 8 years of hourly data, we quantify the storage size and balancing energy needs for highly and fully renewable European power systems for different levels and mixes of wind and solar energy. By applying a dispatch strategy that minimizes the balancing energy needs for a given storage size, the interplay between storage and balancing is quantified, providing a hard upper limit on their synergy. An efficient but relatively small storage reduces balancing energy needs significantly due to its influence on intra-day mismatches. Furthermore, we show that combined with a low-efficiency hydrogen storage and a level of balancing equal to what is today provided by storage lakes, it is sufficient to meet the European electricity demand in a fully renewable power system where the average power generation from combined wind and solar exceeds the demand by only a few percent.

Insects have a pivotal role in ecosystem function, thus the decline of more than 75% in insect biomass in protected areas over recent decades in Central Europe1 and elsewhere2,3 has alarmed the public, pushed decision-makers4 and stimulated research on insect population trends. However, the drivers of this decline are still not well understood. Here, we reanalysed 27 years of insect biomass data from Hallmann et al.1, using sample-specific information on weather conditions during sampling and weather anomalies during the insect life cycle. This model explained variation in temporal decline in insect biomass, including an observed increase in biomass in recent years, solely on the basis of these weather variables. Our finding that terrestrial insect biomass is largely driven by complex weather conditions challenges previous assumptions that climate change is more critical in the tropics5,6 or that negative consequences in the temperate zone might only occur in the future7. Despite the recent observed increase in biomass, new combinations of unfavourable multi-annual weather conditions might be expected to further threaten insect populations under continuing climate change. Our findings also highlight the need for more climate change research on physiological mechanisms affected by annual weather conditions and anomalies.

Untangling the complex effects that different air pollution and climate change factors cause to forest ecosystems is challenging. Supersites, that is, comprehensive measurement sites where research and monitoring of the whole soil–plant–atmosphere system can be carried out, are suggested as a refinement of the current monitoring and research efforts in Europe. This chapter identifies and discusses key measurements to be carried out at such supersites, with a focus on four topical subjects: the carbon, nitrogen, ozone and water budgets. This kind of holistic approach is vital to a realistic translation of the ongoing changes in climate and air quality into research on the impacts on forest ecosystems. Such an integrated effort requires a considerable use of resources at highly instrumented measurement sites and can only be achieved by building on existing infrastructures.

Despite the availability of extensive literature on the benefits and optimization of integrated thermal-electric grids, the dynamics aspects of their operation are not often investigated and well understood. Combined Heat and Power (CHP) units that simultaneously generate electricity and useful heat are one of the main coupling elements between thermal and electric systems with complex dynamic behavior. This paper describes the effort to develop a dynamic model of a CHP unit that will be adequate for use in studies of integrated thermal-electric grids. The proposed model consists of the combustion engine, heat exchanger, exhaust heat exchanger and an induction generator. The developed model is calibrated using parameters of a CHP unit with the goal to validate the behavior of the model against the hardware testbed with the same CHP unit in the laboratory at the Research Center for Combined Smart Energy Systems (CoSES) of the Technical University of Munich (TUM). The individual components, internal combustion engine, heat exchanger, exhaust heat exchanger and induction generator, are modeled separately in from Modelica library. The water heat exchanger and the exhaust heat exchanger are modelled considering the condensing effect of water.

This paper describes the implementation of Power hardware-in-the-loop (PHIL) infrastructure of the CoSES laboratory at TU Munich. We present a control system framework for PHIL test-beds with distributed real-time controllers, using NI Veristand environment. This framework combines real-time computation with software in charge of secondary and tertiary control. The arrangement works as a real-time control environment, with an API access for connection to computation tools and algorithms. Two experiments are presented to validate the PHIL performance and to demonstrate the use of proposed PHIL control framework in investigation of an Optimal Power Flow (OPF) algorithm.

Abstract Conventional generation units are subject to a changing economic environment and have to adjust their role for modern society's power generation. With substantial amounts of renewable energy production encountering the markets, thermal power plants are facing an increased need for flexible operation and decreasing revenues from selling electricity. Technical adaptations are necessary, though have to be redeemed within very short time spans to secure the plant's profitability. Dynamic simulation in this context serves as a helping tool to evaluate technical improvements and is an established tool in industry as well as in research institutes. This paper focuses on the detailed modelling of a hard coal-fired power plant using the thermohydraulic simulation code Apros. Characteristic of this model is the implementation of the major part of the control system together with the physical model. The comprehensive model enables detailed dynamic simulations with very small error values to process data, as to be seen in the validation. As an application example, the extension of a qualified load jump for secondary control power is realised. The dynamic simulation is thereby used to clarify necessary modifications in the control system and to assess the implications on plant operation.

Abstract Feeding solid oxide fuel cells (SOFCs) with gas from biomass gasification is promising with regard to highly efficient power generation. But it is also intricate since biogenic contaminants are harmful to state-of-the-art anode materials. In this work the influence of phenol as a biogenic model contaminant on the performance of single solid oxide fuel cells was studied under realistic conditions. For this purpose Ni/YSZ anode supported cells were operated with simulated bio-syngas, applying an electrical load of 0.34 A/cm2. Over a duration of several hundreds of hours phenol was periodically added to the fuel gas. The tests showed that for the lowest concentration of phenol no accelerated degradation could be observed regarding cell potential and electrical impedance measurements, but disintegration of the Ni/YSZ support took place. Metal dusting of the anode support was found to be the most important mechanism of degradation.