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AbstractIn this paper, we introduce and test a framework to qualitatively assess the environmental impact of climate adaptation innovations with the ambition to facilitate the implementation of these adaptations. The framework was designed to enable continuous environmentally conscious benchmarking based on three environmental performance indicators: sustainable design, environmental impact and ecological impact. It was pilot tested by uninvolved experts and key-persons for two large-scale nature-based flood adaptation innovations in the Netherlands and discussed with environmental assessment professionals. Our findings indicate how the inclusion of our framework helps to identify important knowledge gaps regarding environmental co-benefits and trade-offs, and can be beneficial to both those developing the innovation and the local authorities charged with assessing the suitability of innovations. We conclude by noting how the incorporation of environmental impact assessment from the design stage of adaptations could supplement existing environmental assessment regulations pre-empting concerns rather than reacting to them.

Diode rectifiers (DRs) have elicited increasing interest from both industry and academiaas a feasible alternative for connecting offshore wind farms (OWFs) to HVDC networks. However,before such technology is deployed, more studies are needed to assess the actual capabilities ofDR-connected OWFs to contribute to the secure operation of the networks linked to them. This studyassessed the capability of such an OWF to provide support to an onshore AC network by means of(active) power oscillation damping (POD). A semi-aggregated OWF representation was considered inorder to examine the dynamics of each grid-forming wind turbine (WT) within a string whenproviding POD, while achieving reasonable simulation times. Simulation results corroboratethat such an OWF can provide POD by means of OWF active power controls similar to thosedeveloped for OWFs connected to HVDC via voltage source converters, while its grid-forming WTsshare the reactive power consumption/production and keep the offshore voltage frequency andmagnitude within their normal operating ranges. Open-loop test results show that such capabilitycan, however, be restricted at operating points corresponding to the lowest and highest values ofactive power output.

Abstract The paper presents a model-based approach to supporting battery selection for a fuel cell (FC)-based auxiliary power unit (APU). It is introduced to a case study of electrical power production and consumption management in a truck anti-idling application of a diesel-powered FC-based APU, a system under development in FCGEN, a FCH JU European project of the FP7 program. With fuel cell and related technologies increasingly competing with others in the market, they need to form complete systems with matching and well-balanced components to enable using the technology to its best. Within the whole system, the battery, serving as an energy buffer, represents a medium-cost element, but it affects the operating parameters importantly. Within the scope of this study, a purpose-oriented model of the diesel powered FC-based system is developed together with a realistic load scenario for the comparison of three batteries. The battery size and type are investigated and discussed in the light of the simulation results.

Lithium-ion batteries are becoming increasingly important for electrifying the modern transportation system and, thus, hold the promise to enable sustainable mobility in the future. However, their large-scale application is hindered by severe safety concerns when the cells are exposed to mechanical, thermal, or electrical abuse conditions. These safety issues are intrinsically related to their superior energy density, combined with the (present) utilization of highly volatile and flammable organic-solvent-based electrolytes. Herein, state-of-the-art electrolyte systems and potential alternatives are briefly surveyed, with a particular focus on their (inherent) safety characteristics. The challenges, which so far prevent the widespread replacement of organic carbonate-based electrolytes with LiPF6 as the conducting salt, are also reviewed herein. Starting from rather facile electrolyte modifications by (partially) replacing the organic solvent or lithium salt and/or the addition of functional electrolyte additives, conceptually new electrolyte systems, including ionic liquids, solvent-free, and/or gelled polymer-based electrolytes, as well as solid-state electrolytes, are also considered. Indeed, the opportunities for designing new electrolytes appear to be almost infinite, which certainly complicates strict classification of such systems and a fundamental understanding of their properties. Nevertheless, these innumerable opportunities also provide a great chance of developing highly functionalized, new electrolyte systems, which may overcome the afore-mentioned safety concerns, while also offering enhanced mechanical, thermal, physicochemical, and electrochemical performance. International audience

In future power systems, widespread small-scale energy storage systems (ESSs) can be aggregated to provide ancillary services. In this context, a new load frequency control scheme which incorporates the energy storage aggregator (ESA) and its associated disturbance observer is proposed. The disturbance observer is designed to supplement the secondary frequency control for the ESA, therefore the system frequency response and recovery can be improved. Within the ESA, a finite-time leader-follower consensus algorithm is proposed to control the small-scale ESSs via sparse communication networks. This algorithm ensures that the ESA tracks the frequency control signals, while the state-of-charge among each ESS is balanced in finite-time. The external characteristics of the ESA will resemble to that of one large-scale ESS. Numerical examples demonstrate the convergence of the ESA under different communication graphs. The effectiveness of the entire scheme for power system frequency control is validated under a variety of scenarios that include contingency and normal operation. NRF (Natl Research Foundation, S’pore)

A real-time combustion model was assessed and applied to simulate BMEP (Brake Mean Effective Pressure) and NOx (Nitrogen Oxide) emissions in an 11.0 L FPT Cursor 11 diesel engine for heavy-duty applications. The activity was carried out in the frame of the IMPERIUM H2020 EU Project. The developed model was used as a starting base to derive a model-based combustion controller, which is able to control indicated mean effective pressure and NOx emissions by acting on the injected fuel quantity and main injection timing. The combustion model was tested and assessed at steady-state conditions and in transient operation over several load ramps. The average root mean square error of the model is of the order of 110 ppm for the NOx simulation and of 0.3 bar for the BMEP simulation Moreover, a statistical robustness analysis was performed on the basis of the expected input parameter deviations, and a calibration sensitivity analysis was carried out, which showed that the accuracy is almost unaffected when reducing the calibration dataset by about 80%. The model was also tested on a rapid prototyping device and it was verified that it features real-time capability, since the computational time is of the order of 300&ndash s. Finally, the basic functionality of the model-based combustion controller was tested offline at steady-state conditions. 400 µ

Long-term liquid phase studies of the activity in the formic acid-mediated hydrogenation of MAc to SAc were conducted in a fixed bed continuous reactor for two relevant situations: neutralising maleic and formic acids with NaOH and at the pH determined by both acids. Deactivation could only be observed when the catalyst was subjected to a WHSV of MAc above 13 gMAc gcat−1 h−1. Despite this deactivation, the reaction conditions can be adjusted (lowering the reaction temperature and/or decreasing the WHSV) to compensate for the loss of activity. Thus, for the neutralisation case, the catalyst could present a yield of SAc close to 100% for at least 400 h at a WHSV-MAc of 13 gMAc gcat−1 h−1 by setting the temperature at 180 °C, corresponding to an overall productivity above 5300 g of SAc per gcat, equivalent to more than 107 kg of SAc per gPd. An in-depth study of the catalyst used under these severe conditions was also conducted using a number of physico-chemical techniques. The sintering of Pd particles, Pd leaching, reduction–carbidization of Pd2+ and/or Pd into Pd carbides (PdCx) and deposition of organic compounds were identified in the spent catalysts for both the neutralised and acid runs. The presence of Na+ and of CO chemisorbed at the surface of the catalyst were also detected in the neutralised and acid cases, respectively. The rinsing of the catalyst with aqueous H2SO4 or treating the catalyst at 200 °C with streams containing O2 or H2 did not reactivate the catalyst. We concluded that the relevant causes of deactivation are Pd leaching and deposits of organic compounds; CO poisoning is also likely in the acid case. This is in agreement with the fact that deactivation is detected under high MAc-WHSV: the rate of leaching, CO chemisorption and deposition accelerates upon increasing it.