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The paper proposes a new concept of protection philosophy for Dutch distribution grids with high penetration of renewable energy. Conventional protection concepts are normally based on protection schemes that consist of definite or inverse time overcurrent relays. In future power systems, these schemes can lead to high fault clearing times, unselective tripping and massive DG disconnections, which are not acceptable in a deregulated multi-owner energy market. This research work proposes an efficient intelligent communication-based protection algorithm that implements different multi-functional protection principles supported by blocking schemes. The real-time organization of both the hardware architecture and communication infrastructure of the protection algorithm is illustrated in detail. Special emphasis is given to the network reconfiguration scenario cases and detailed simulation results of such illustrative studied cases are provided. The new protection strategy guarantees protection selectivity and provides DG-unit availability during and after the fault. The intelligent algorithm is applied on existing Dutch distribution network and meaningful conclusions are derived.

A new Proportional-Integral (PI) tuning method based on Linear Matrix Inequalities (LMIs) is presented. In particular, an LMI-based optimal control problem is solved to obtain a sparse feedback that provides the PI tuning. The ASCE Test Canal 1 is used as a case study. Using a linearised model of the canal, different tunings for the design of the PI controller are developed and tested using the software Sobek. Furthermore, the proposed method is also compared with other tunings proposed for the same canal available in the literature. Our results show that the proposed method reduces by half the maximum errors with respect to other assessed alternatives and minimizes undesired mutual interactions between canal pools. Also, our method improves the optimality degree of the PI tuning by 30%. Therefore, it is concluded that the LMI based PI controllers lead to satisfactory performance in regulating water levels and canal flows/structure outflows, outperforming other tested alternatives, thus becoming a useful tool for irrigation canal control.

Climate change is already having substantial adverse impacts across the globe, and these are projected to worsen dramatically in years to come without rapid and far-reaching measures to transition to low carbon development. Crucially, massive financial investment will be necessary to fast track a low carbon transition and the level of finance required will arguably be well beyond the resources and capability of public finance alone. With a focus on climate finance in Asia and the Pacific and drawing empirical evidence from our work in Fiji and Indonesia, this article investigates complex realities of climate finance as it flows to the recipient countries. This article reveals how existing structures and power relations impact the outcomes of financing transitions to low carbon energy. The findings suggest that climate finance flows primarily to the most bankable, lowest risk, highest return, and often the largest scale projects. Moreover, the prioritisation of large-scale projects tends to result in preference for on-grid as opposed to off-grid renewable infrastructures, the reinforcement of technological preferences of powerful stakeholders, and the exclusion of smaller projects and developers. Consequently, it could exacerbate rather than ameliorate existing inequalities with the most vulnerable groups gaining little if any benefits from such finance. This article concludes by highlighting the importance of designing climate finance governance and financial products that could mitigate multi-scalar inequalities and design the mechanisms that internalise the need for critical, intersectional co-benefit delivery. ; Energie and Industrie

AbstractThis work presents a practical approach to designing an optical filter for thermal management for photovoltaic modules. The approach emphasizes the practicality of manufacturing over optical performance. Simulation work demonstrates that, for an interdigitated back contact solar cell architecture, complete rejection of infrared radiation offers limited thermal benefits requiring highly complex optical filter designs. An alternative approach consists of reducing thermalization losses by providing reflectance at lower wavelength values. An optical filter design that fulfills this requirement is possible using simple structures based on two materials and taking advantage of the harmonics present in quarter wavelength optical thickness designs. The filter is later optimized for angular performance via second‐order algorithms, resulting in a device consisting of only 15 thin‐film layers. Performance simulations on two locations, Delft (the Netherlands) and Singapore, estimate a temperature reduction of 2.20°C and 2.45°C, respectively. In a single year, the optical loss produced by the filter is not compensated via temperature reduction. However, improvements in the annual degradation rate show that in Singapore, the overall effect of the filter on the lifetime DC energy yield is positive.

The circular economy has been heralded as a potential driver for sustainable development by business, academia, and policymakers. In a future circular economy, new business models are needed that slow, close and narrow resource loops to address key resource and climate challenges. After a phase of excitement and inspiration, an operationalization phase needs to start to ensure the best possible implementation and transition towards a circular economy. This operationalization phase will involve the development of products, processes and business models that significantly lower the negative impact on the environment, reduce waste and resource pressures and, rather, create a positive impact on society and environment. This paper focuses on the circular business model lens as a comprehensive way of addressing business innovation. Within this evolving circular economy operationalization phase, several tools, approaches and methods are emerging that could support circular business model innovation. This paper seeks to create a comprehensive tools overview through a literature and practice review. It provides structure to the emerging range of tools, methods and approaches, and, based on this, a guideline for future tool development. Finally, it gives an overview of opportunities and gaps as well as a future agenda for research and practice.

This deliverable is a halfway summary of the FP7 project UMBRELLA. It describes the objectives and the results achieved by the end of the second of four project years. UMBRELLA is also cooperating with the related FP7 project iTesla, i.e. some public workshops are performed commonly, test environments are harmonized and a common proposal on potential development of future TSO rules will be proposed at the end of both projects in 2015.

Despite considerable advances in process understanding, numerical modeling, and the observational record of ice sheet contributions to global mean sea-level rise (SLR) since the Fifth Assessment Report (AR5) of the Intergovernmental Panel on Climate Change, severe limitations remain in the predictive capability of ice sheet models. As a consequence, the potential contributions of ice sheets remain the largest source of uncertainty in projecting future SLR. Here, we report the findings of a structured expert judgement study, using unique techniques for modeling correlations between inter- and intra-ice sheet processes and their tail dependences. We find that since the AR5, expert uncertainty has grown, in particular because of uncertain ice dynamic effects. For a +2 °C temperature scenario consistent with the Paris Agreement, we obtain a median estimate of a 26 cm SLR contribution by 2100, with a 95th percentile value of 81 cm. For a +5 °C temperature scenario more consistent with unchecked emissions growth, the corresponding values are 51 and 178 cm, respectively. Inclusion of thermal expansion and glacier contributions results in a global total SLR estimate that exceeds 2 m at the 95th percentile. Our findings support the use of scenarios of 21st century global total SLR exceeding 2 m for planning purposes. Beyond 2100, uncertainty and projected SLR increase rapidly. The 95th percentile ice sheet contribution by 2200, for the +5 °C scenario, is 7.5 m as a result of instabilities coming into play in both West and East Antarctica. Introducing process correlations and tail dependences increases estimates by roughly 15%.