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[EN] The objective of this article is to compare the behaviour of the most representative domestic hot water systems (DHW) in single-family buildings. The study evaluates the energy consumption, equivalent CO2 emissions and cost for each system over a 15-year life period. This analysis is carried out in four cli- matic zones across Europe to observe the influence of climatic conditions on the results. The four climatic zones are located in the cities of Athens, Madrid, London and Berlin. The analysed systems are: a) natural gas-fired instantaneous water heaters, b) electric storage water heater, c) solar thermal system with gas- fired instantaneous, d) solar thermal system with electric storage water heater, e) air-source heat pump, f) photovoltaic system with electric storage water heater, and g) photovoltaic system with air-source heat pump. This range of technologies covers the most likely solutions to be implemented across domestic buildings in Europe.The heat pump system (HPWH) with PV considering self-consumption shows the lowest environmen- tal impact in all zones, but is not an attractive investment in the coldest zones due to lower natural gas prices. Thermal solar systems have a high purchase and maintenance costs which do not compensate their energy savings. The PV HPWH system has a greater reduction of emissions and a lower cost than HPWH across a 15-year life. The gas boiler system has the lowest cost in a 15-year period in the coldest areas, despite having a greater environmental impact than the heat pump.(c) 2023 Elsevier B.V. All rights reserved.

The lifetime and reliability of power transformers are primarily dependent on the hot-spot temperature in the windings, as temperature is the most important factor determining the insulation degradation rate. Key to removing the heat from the transformer is the radiator which must be carefully designed to keep the temperatures within limits under all operating conditions whilst minimizing the transformer size, weight and cost. This paper compares the analytical method used to predict the radiator performance with computational fluid dynamics (CFD) models in terms of heat dissipation. It is found that the analytical method and CFD models give similar results in the air natural (AN) cooling modes, whereas the analytical method overestimates the heat dissipation in the air forced (AF) cooling modes. Moreover, the thermal conduction effect in the radiator wall is investigated under different operating conditions and for different radiator sizes using the CFD models. The simulation results indicate that the radiator wall contributes to 6%-10% of the total heat dissipation under some circumstances and therefore should not be simply ignored in radiator models.

Selective removal of coatings by lasers can facilitate the reuse of coated tools in a circular economy. In order to optimise and control the process, it is essential to study the impact of process input variables on process performance. In this paper, coating removal from tooling was carried out using a picosecond a pulsed fibre laser, in order to investigate the effects of laser pulse energy, pulse frequency, galvo scanning speed and scanning track stepover. A fractional factorial design of experiments and analysis of variance was used to optimise the process; considering cleaning rate, specific energy consumption and surface integrity as assessed by changes in surface roughness and composition of the tooling after laser cleaning. The results shows synergy between cleaning rate and specific energy with the laser pulse frequency and galvo scanning speed as the two most significant factors, while the laser pulse energy had the greatest contribution to changes in surface composition. Based on extensive experiments, the relationship between processing rate and system specific energy consumption was mathematically modelled. The paper contributes a new specific energy model for laser cleaning and provides a benchmark of the process energy requirements compared to other manufacturing processes. Additionally, the generic scientific learning from this is that the rate of energy input is a key tool for maximising cleaning rate and minimising specific energy requirements, while the intensity of energy applied, is a key metric that influences surface integrity. More complex factors, influence the surface integrity.

Abstract: This study evaluates the economic and environmental benefits of implementing the proposed REcovered Nitrogen from manURE (RENURE) criteria as mineral fertiliser into the Nitrates Directive (ND) to facilitate the utilisation of minerals from manure. Implementing the RENURE amendment could significantly contribute to sustainability goals in an economic way, offering a 4.8 % reduction in economic costs in livestock-dense regions including Brittany (-0.7 %), Lombardy (-2.3 %), Flanders (-2.6 %), Lower Saxony (-4.7 %), Catalonia (-4.8 %), North-Rhine Westphalia (-4.8 %), and the Netherlands (-5.0 %). Through spatially explicit multi-agent modeling, the study revealed that the RENURE amendment not only promises economic benefits, but also enhances nitrogen circularity by 1.3 % and reduces greenhouse gas emissions by 6 % in these areas. These findings highlight the potential of nutrient recovery and reuse under RENURE to address both economic and environmental challenges, supporting the European Union's (EU) Farm-to-Fork strategy (F2F) goals of reducing nutrient emissions to the air and fertilizer use.

Environmental tax reform (ETR), a shift from labour to carbon taxes, has been mostly modelled using general equilibrium (GE) analysis. Since a low-carbon transition will require deep transformations, one will also have to address out-of-equilibrium dynamics and increased agent heterogeneity. Unlike GE models, agent-based models (ABMs) are well equipped to deal with this. We therefore replicate a recent GE model for ETR using an agent-based approach. This process, known as "agentization", allows assessing similarities as well as differences in policy impacts between the two modelling approaches, in turn providing a test of the robustness of the GE results. We find that the agent-based model is able to replicate many results of the general equilibrium analysis, while revealing strengths and weaknesses of both model types. We discuss concrete implementation steps and difficulties experienced in the GE-ABM translation process. We illustrate the potential of ABM by extending the model in several directions. We show that heterogeneous subsistence consumption can increase the space for combining a double dividend with an equity goal, and that overall macro-economic results can conceal important distributional impacts when green preferences and labour supply elasticities vary.

Periglacial alluvial fans are common in northwestern and central Europe and their pre-Holocene stratigraphic records typically date back to late Middle Pleniglacial and Late Pleniglacial (late MIS3 and 2). Preserved stratigraphic records that include an entire interglacial-glacial cycle have, so far, not been described and it is thus unknown how periglacial alluvial fans responded during a full cycle of interglacial-glacial climate changes. In this paper, we reconstruct the evolution of the Eerbeek periglacial alluvial fan in the Netherlands which was deposited during the late Saalian (MIS 6) to late Weichselian (MIS 2) period, including the entire last interglacial–glacial cycle (MIS 5-2). Our reconstruction is based on 48, up-to 45-m deep borehole and Cone Penetration Test (CPT) logs that allowed the construction of an 8-km long longitudinal and a 7-km long transverse cross section over the Eerbeek periglacial alluvial fan. Age control was provided by means of 17, previously published, Optically Stimulated Luminescence ages of two boreholes on the fan, and 14 14C ages from three boreholes and a nearby, now abandoned, quarry.Overlying a thick, late Saalian (MIS 6) alluvial fan record, is a 4- to 18-m thick alternation of distinct organic (mainly peat and humic clays), siliciclastic alluvial fan (coarse- and medium-grained sands), Rhine (coarse- and medium grained sands), and aeolian (mainly medium-grained sands) stratigraphic units. Organic levels indicate fan stability during the Eemian interglacial (MIS 5e), and Brørup (MIS 5c), Odderade–Ognon interstadial complex (MIS 5a), and Middle Pleniglacial (MIS 3) interstadials 14, 13, 12 and 11 as well as late MIS 2 interstadial 1a. Clastic sediments indicate alluvial fan activity during the Herning (MIS 5d), Rederstall (MIS 5b), Ognon stadial complex (late MIS 5a), Early Pleniglacial (MIS 4) and upper Middle Pleniglacial (upper MIS 3) stadials 13, 12 and 11. Sediments from the coldest and driest period of the Last Glacial (late MIS 3 and MIS 2) are absent and following a phase of aeolian activity, the fan was only reactivated at the MIS 2 to MIS 1 transition (stadial 1). We attribute the absence of fan activity during the coldest period of the last interglacial-glacial cycle to the eastward orientation of the fan making it less sensitive to permafrost melt.The colder MIS substages and stadials in which the Eerbeek fan was active coincided with the presence of permafrost and/or a seasonal, deeply frozen soil, and a relatively humid climate during which vegetation was largely absent. The presence of channels that dissect the underlying organic units suggests that the Eerbeek fan initially responded to the changes from interstadials to stadials by means of erosion. As climate cooled and permafrost/deep frost developed, the fan switched to alluvial aggradation. The consistent presence of coarsening-fining upward sequences suggests a relation with cycles of increased overland flow due to increasingly more frozen subsoil conditions. The fan stratigraphy therefore shows the direct coupling between warmer-colder MIS substages and interstadial-stadial climate cyclicity and alluvial fan response over the entire last interglacial-glacial cycle.