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The objective of this paper is to explain novel sustainable robotics solutions for cities. Those new proposals appear under the ECHORD++ project which is a good tool to meet academia and industry with the objective of providing innovative technological solutions. In this paper, authors explain the tool as well as the methodology to promote robotics research in urban environments, and the on-going experience will demonstrate that huge advances are made in this field. Peer Reviewed

Wave power is a potential technology for generating sustainable renewable energy. Several types of wave energy converters (WECs) have been proposed for this purpose. WECs operate in a harsh maritime environment that sets strict limitations on how and when the device can be economically and safely reached for maintenance. Thus, to ensure profitable energy generation over the system life cycle, system reliability is a key aspect to be considered in WEC development. In this article, we describe a reliability analysis approach for WEC development, based on the use of reliability block diagram (RBD) modelling. We apply the approach in a case study involving a submerged oscillating wave surge converter device concept that utilizes hydraulics in its power take-off system. In addition to describing the modelling approach, we discuss the data sources that were used for gathering reliability data for the components used in a novel system concept with very limited historical or experimental data available. This includes considerations of the data quality from various sources. As a result, we present examples of applying the RBD modelling approach in the context of WEC development and discuss the applicability of the approach in supporting the development of new technologies.

District heating is a network of pipes through which heat is delivered from a centralised source. It is expected to play an important role in the decarbonisation of the energy sector in the coming years. In district heating, heat is traditionally generated through fossil fuels, often with combined heat and power (CHP) units. However, increasingly, waste heat is being used as a low carbon alternative, either directly or, for low temperature sources, via a heat pump. The design of district heating often has competing objectives: the need for inexpensive energy and meeting low carbon targets. In addition, the planning of district heating schemes is subject to multiple sources of uncertainty such as variability in heat demand and energy prices. This paper proposes a decision support tool to analyse and compare system designs for district heating under uncertainty using stochastic ordering (dominance). Contrary to traditional uncertainty metrics that provide statistical summaries and impose total ordering, stochastic ordering is a partial ordering and operates with full probability distributions. In our analysis, we apply the orderings in the mean and dispersion to the waste heat recovery problem in Brunswick, Germany.

The EU has set clear targets regarding energy conservation of buildings and heavily supports activities towards achieving these targets on a European scale. The Green Deal, renovation wave, Energy Performance of Buildings Directive (EPBD) and Energy Efficiency Directive (EED) are some examples of EU's actions. For more than a decade, Energy Performance Certificates provide detailed data about the current energy needs of a building/building unit as well as information about the building construction and systems. A Building Renovation Passport (BRP) has, on a European level lately, been conceived as a tool that can stimulate cost-effective renovation in the form of a long-term basis, step-by-step deep renovation roadmap following defined quality criteria, and outline energy renovation measures that will improve the energy performance of the building. A Digital Building Logbook (DBL) is another tool that can serve as an archive where all building information can be stored and continuously updated. In this way, a full record of the building history will be electronically available with data regarding construction plans and permits, maintenance and system replacement activities, energy and heat consumption and production, etc. Building Renovation Passports and the Digital Building Logbook are tools that can help in achieving energy efficiency in existing buildings and contribute to reaching the EU renovation wave goals. The objective of this report is to investigate how the current EPC schemes best make the link towards the BRP and the DBL to further incentivise and stimulate cost-effective deep energy renovations of buildings across Europe. Three surveys were carried out to collect relevant information about the current status of the EPC data records and to identify stakeholders' potential needs, perceptions, thoughts and expectations, regarding a future connection between the EPC and the BRP or DBL. These surveys were prepared in two forms: using an excel file format circulated via email, and through an online questionnaire. Their completion was carried out by 16 countries. Regarding the EPCs, the state or regional energy agencies are the owner of the EPC data records and make full use of them. Their current main usage is for statistical reasons in the majority of the countries and their access is publicly available in half of the responding countries. Many common data is stored in the EPC database which can be linked with other tools (half of the EPC databases are already linked with another source). Regarding the BRP, a review of existing European schemes showed that successful BRPs have combined the renovation advice with financial support, legal requirements and/or communication campaigns. An important factor of the BRP is that it should be issued by a qualified expert and should provide customised measures for the specific building together with the investment costs per renovation measure(s). The DBL analysis showed that it should provide access to building information and contribute to better decision-making for future interventions as well as operation, use and maintenance records. The building owner/user is proposed to have full access to the logbook and provide/input about energy bills and building plans/construction materials info. An important aspect is that every time the building undergoes intervention works, the DBL should be updated accordingly. The most important barrier is the lack of motivation to update the DBL contents followed by the absence of synergies and consistency with other tools. Another interesting finding is that both BRP and DBL should be fed automatically by EPC data without any user interference. There is a clear possible interconnection between EPC data and BRP and DBL future contents. In addition, BRP can be an instrument to increase the renovation rates and DBLs are necessary for the management of buildings' information. The linkage of EPC data and BRP and DBL can be strengthened by introducing BRP and DBL as voluntary schemes under national incentives and should be fully implemented once they have demonstrated acceptance by the stakeholders.

The hot summer of 2018 posed many challenges with regard to water shortages and yield losses, especially for agricultural production. These agricultural impacts might further pose consequent threats for the environment. In this paper, we deduce the impact of droughts on agricultural land management and on water quality owing to nitrate pollution. Using national statistics, we calculate a Germany-wide soil surface nitrogen budget for 2018 and deduce the additional N surplus owing to the dry weather conditions. Using a model farm approach, we compare fertilization practices and legal restrictions for arable and pig breeding farms. The results show that, nationwide, at least 464 kt of nitrogen were not transferred to plant biomass in 2018, which equals an additional average nitrogen surplus of 30 kg/ha. The surplus would even have amounted to 43 kg/ha, if farmers had continued their fertilization practice from preceding years, but German farmers applied 161 kt less nitrogen in 2018 than in the year before, presumably as a result of the new implications of the Nitrates Directive, and, especially on grassland, owing to the drought. As nitrogen surplus is regarded as an “agri-drinking water indicator” (ADWI), an increase of the surplus entails water pollution with nitrates. The examples of the model farms show that fertilization regimes with high shares of organic fertilizers produce higher nitrogen surpluses. Owing to the elevated concentrations on residual nitrogen in soils, the fertilization needs of crops in spring 2019 were less pronounced than in preceding years. Thus, the quantity of the continuously produced manure in livestock farms puts additional pressure on existing storage capacities. This may particularly be the case in the hot-spot regions of animal breeding in the north-west of Germany, where manure production, biogas plants, and manure imports are accumulating. The paper concludes that water shortages under climate change not only impact agricultural production and yields, but also place further challenges and threats to nutrient management and the environment. The paper discusses preventive and emergency management options for agriculture to support farmers in extremely dry and hot conditions.

Thin (approximately 10 nm) oxide buffer layers grown over lead-halide perovskite device stacks are critical for protecting the perovskite against mechanical and environmental damage. However, the limited perovskite stability restricts the processing methods and temperatures (<=110 C) that can be used to deposit the oxide overlayers, with the latter limiting the electronic properties of the oxides achievable. In this work, we demonstrate an alternative to existing methods that can grow pinhole-free TiOx (x = 2.00+/-0.05) films with the requisite thickness in <1 min without vacuum. This technique is atmospheric pressure chemical vapor deposition (AP-CVD). The rapid but soft deposition enables growth temperatures of >=180 ��C to be used to coat the perovskite. This is >=70 ��C higher than achievable by current methods and results in more conductive TiOx films, boosting solar cell efficiencies by >2%. Likewise, when AP-CVD SnOx (x ~ 2) is grown on perovskites, there is also minimal damage to the perovskite beneath. The SnOx layer is pinhole-free and conformal, which reduces shunting in devices, and increases steady-state efficiencies from 16.5% (no SnOx) to 19.4% (60 nm SnOx), with fill factors reaching 84%. This work shows AP-CVD to be a versatile technique for growing oxides on thermally-sensitive materials. R.D.R and R.A.J contributed equally. 23 pages. 6 figures