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ON 16 NOVEMBER 2000, the final report of the World Commission on Dams (WCD) was launched in London, in the presence of South Africa’s former president Nelson Mandela. This represented a remarkable milestone in the history of dam policy and politics. During its two-year existence, WCD had conducted the most extensive review of research and evidence regarding the planning, impacts, and management of large dams. It had engaged with numerous stakeholders around the globe. It also made comprehensive recommendations about how to improve dam planning and management.

We analysed the effect of applying Dutch thermal efficiency standards of residential dwellings, conversion efficiency, appliance fuel mixes and appliance ownership rates, to the UK residential sector. We found that although aggregate energy consumption does not change significantly, pollution emissions are reduced significantly. Thus, the primary difference between housing and appliance stocks in the two regions is in terms of fuel mixes. However, improved thermal efficiency does allow for increased dwelling warmth without increasing emissions. Adapting Dutch standards in the UK would lead to a one-time improvement of the environmental situation, after which the trend is continued.

Since a superconductor has no resistance below a certain temperature and can therefore save a large amount of energy dissipated, it is a 'green' material by saving energy loss and hence reducing carbon emissions. Recently the massive manufacture of high-temperature superconducting (HTS) materials has enabled superconductivity to become a preferred candidate to help generation and transportation of cleaner energy. One of the most promising applications of superconductors is Superconducting Magnetic Energy Storage (SMES) systems, which are becoming the enabling engine for improving the capacity, efficiency, and reliability of the electric system. SMES systems store energy in the magnetic field created by the flow of direct current in a superconducting coil. SMES systems have many advantages compared to other energy storage systems: high cyclic efficiency, fast response time, deep discharge and recharge ability, and a good balance between power density and energy density. Based on these advantages, SMES systems will play an indispensable role in improving power qualities, integrating renewable energy sources and energizing transportation systems. This thesis describes an intensive study of superconducting pancake coils wound using second-generation(2G) HTS materials and their application in SMES systems. The specific contribution of this thesis includes an innovative design of the SMES system, an easily calculated, but theoretically advanced numerical model to analyse the system, extensive experiments to validate the design and model, and a complete demonstration experiment of the prototype SMES system. This thesis begins with literature review which includes the introduction of the background theory of superconductivity and development of SMES systems. Following the literature review is the theoretical work. A prototype SMES system design, which provides the maximum stored energy for a particular length of conductors, has been investigated. Furthermore, a new numerical model, which can predict all necessary operation parameters, including the critical current and AC losses of the system, is presented. This model has been extended to analyse superconducting coils in different situations as well. To validate the theoretical design and model, several superconducting coils, which are essential parts of the prototype SMES system, together with an experimental measurement set-up have been built. The coils have been energized to test their energy storage capability. The operation parameters including the critical current and AC losses have been measured. The results are consistent with the theoretical predictions. Finally the control system is developed and studied. A power electronics control circuit of the prototype SMES system has been designed and simulated. This control circuit can energize or discharge the SMES system dynamically and robustly. During a voltage sag compensation experiment, this SMES prototype monitored the power system and successfully compensated the voltage sag when required. By investigating the process of building a complete system from the initial design to the final experiment, the concept of a prototype SMES system using newly available 2G HTS tapes was validated. This prototype SMES system is the first step towards the implementation of future indsutrial SMES systems with bigger capacities, and the knowledge obtained through this research provides a comprehensive overview of the design of complete SMES systems. The full text of this thesis is not available due to ongoing discussions regarding publication

The database presents the scenario results of an exploratory research, carried out at the International Institute for Applied Systems Analysis (IIASA): the Low Energy Demand (LED) study (Grubler et al. 2018). The LED scenario explored how far transformative changes that combine technological changes, end-use efficiency, and new business models for energy service provision can lead for lowering energy demand, and how these changes could drive deep decarbonisation in the long-term. The scenario development methodology included a bottom-up analysis of how currently existing, though often embryonic, social, institutional, and technological trends could become mainstream with resulting step-changes in efficiency and resulting lowered energy demand. The bottom-up demand estimations were then further explored for their supply side and emissions and climate implications with a top-down modeling framework drawing on the Shared Socioeconomic Pathways (SSP) framework (Riahi et al. 2017). The results show that global final energy demands can be drastically reduced in 2050, to around 245 EJ/yr, or 40% lower than today, whilst significantly expanding human welfare and reducing global development inequalities. According to the knowledge of the authors, LED is the lowest long-term global energy demand scenario ever published. The LED scenario meets the 1.5°C climate target in 2100 without overshoot and keeps the global mean temperature increase below 1.5°C with a probability of more than 60%, without requiring controversial negative emission technologies, such as bioenergy with carbon capture and storage (BECCS), that figure prominently in the emission scenario literature (Rogelj et al. 2015, Anderson and Peters 2016, Creutzig et al. 2016, Smith et al. 2016). Furthermore, the beneficial impacts of the LED scenario on a range of other sustainable development goals are also shown, demonstrating that efficiency of energy services provision plays a critical role in reaching low-energy futures without compromising increased living standards in the Global South, while at the same time reducing adverse social and environmental impacts of climate mitigation strategies that focus predominantly on large-scale supply-side transformations. The research is published in a peer-reviewed article in Nature Energy (Grubler et al. 2018) with ample supplementary information. Water consumption and withdrawal data are published in Parkinson et al. (2018). The data is available for download from the LED Database. The content of the LED database and any derived analysis may only be used for non-commercial scientific publications, articles, educational purposes, figures and data tables provided that the source reference pursuant to section 'Required citation' is included and all relevant publications are correctly cited. Partial reproductions of the database content may be stored in online repositories, if this is necessary to comply with a journal's data archiving and access requirements. Such reproductions must be limited to the scope of the manuscript in question, and must include a hyperlink to the source database hosted at https://db1.ene.iiasa.ac.at/LEDDB and the download date from the source database. However, any wholesale duplication, translation, reworking, processing, arrangement, transformation, or reproduction through the internet or any other channels, of the https://db1.ene.iiasa.ac.at/LEDDEB for commercial or non-commercial purposes is not permitted without the explicit written approval of IIASA.

The paper builds around the key messages from the recently completed study — The Economics of Ecosystems and Biodiversity (TEEB). The paper essentially attempts to map the problem encountered in up scaling the findings from site/local scale to national scale. First, the rationale for economic analysis of ecosystem services has been discussed and then the challenges in applying economics to ecosystems and biodiversity have been identified. The paper discusses the role of economic valuation, discounting and necessary indicator for it. Social and cultural context of economic valuation along with the nature of value articulating institutions have been highlighted. Most of these issues typically deal with ecosystem services at site and project level. The paper lays down the need for arriving at national policies from microlevel valuation work. The paper suggests that for national policy formulation and design, valuation and accounting of ecosystem services must be seen in the economy wide context where interdependence of sectors is the key. The paper shows the existing hiatus between this level of analysis of economics of ecosystems and the need for credible national level policies. An attempt has been made to highlight necessary steps to arrive at national level policies on ecosystems management.

ABSTRACT Tire selection has an important impact on the operational costs of heavy-goods vehicles (HGVs). HGV tires are designed on a tradeoff between wear resistance, rolling resistance, and adhesion (skid resistance). High wear resistance tires (high mileage) are replaced less often but use more fuel during operation, and vice versa for low rolling resistance tires. Presently, finding the optimal tire to minimize replacement costs and fuel consumption (greenhouse gas emissions) is challenging due to the difficulty in predicting tire wear for a given operation, since its rate varies with different vehicle configurations (e.g., load, vehicle length, number of axles, type of axle, etc.) and road types (e.g., motorways/highways, minor roads, urban roads, etc.). This article presents a novel empirical tire-wear model that can be used to predict the wear for multi-axle vehicles based on route data and a vehicle model. The first part of the article presents the analytical and experimental development of the model. The second part presents the experimental validation of the model based on 10 months of in-service data totaling 37,000 km of operation. The model predicts tire tread depth within 8% (average error of 2%).

Artículos en revistas Numerical models of transmission-constrained electricity markets are used to inform regulatory decisions. How robust are their results? Three research groups used the same data set for the northwest Europe power market as input for their models. Under competitive conditions, the results coincide, but in the Cournot case, the predicted prices differed significantly. The Cournot equilibria are highly sensitive to assumptions about market design (whether timing of generation and transmission decisions is sequential or integrated) and expectations of generators regarding how their decisions affect transmission prices and fringe generation. These sensitivities are qualitatively similar to those predicted by a simple two-node model. info:eu-repo/semantics/publishedVersion

The attrition of two potential oxygen-carriers for chemical looping, 100 wt% mechanically-mixed, unsupported iron oxide (400 - 600 ?m diameter) and 25 wt% copper oxide impregnated on alumina (600 - 900 ?m diameter), has been studied. The rates of attrition of batches of these particles whilst they were being fluidised and subjected to successive cycles of reduction and oxidation were determined by measuring the rate of production of fine particles elutriated from the bed, as well as progressive changes in the distribution of particle sizes retained in the bed. The ability of the particles to withstand impacts was also investigated by examining the degree of fragmentation of 1 g of reacted particles of known size on projecting them at a target at various velocities. It was found that the mechanical strength of the iron oxide particles deteriorated significantly after repeated cycles of oxidation and reduction. Thus, the rate of elutriation increased ~ 35 fold between the 1st and 10th cycle. At an impact velocity of 38 m/s, the amount of fragmentation in the impact test, viz. mass fraction of particles after impact having a size less than that before impact, increased from ~ 2.3 wt% (fresh particles) to 98 wt% after the 10th cycle. The CuO particles, in comparison, were able to withstand repeated reaction: no signs of increased rates of elutriation or fragmentation were observed over ten cycles. These results highlight the importance of selecting a durable support for oxygen-carriers.

Selective laser melting (SLM) is an additive manufacturing process which enables the creation of intricate components from high performance alloys. This facilitates the design and fabrication of new cellular materials for blast and impact mitigation, where the performance is heavily influenced by geometric and material sensitivities. Design of such materials requires an understanding of the relationship between the additive manufacturing process and material properties at different length scales: from the microstructure, to geometric feature rendition, to overall dynamic performance. To date, there remain significant uncertainties about both the potential benefits and pitfalls of using additive manufacturing processes to design and optimise cellular materials for dynamic energy absorbing applications. This investigation focuses on the out-of-plane compression of stainless steel cellular materials fabricated using SLM, and makes two specific contributions. First, it demonstrates how the SLM process itself influences the characteristics of these cellular materials across a range of length scales, and in turn, how this influences the dynamic deformation. Secondly, it demonstrates how an additive manufacturing route can be used to add geometric complexity to the cell architecture, creating a versatile basis for geometry optimisation. Two design spaces are explored in this work: a conventional square honeycomb hybridised with lattice walls, and an auxetic stacked-origami geometry, manufactured and tested experimentally here for the first time. It is shown that the hybrid lattice-honeycomb geometry outperformed the benchmark metallic square honeycomb in terms of energy absorption efficiency in the intermediate impact velocity regime (approximately 100 m/s). In this regime, the collapse is dominated by dynamic buckling effects, but wave propagation effects have yet to become pronounced. By tailoring the fold angles of the stacked origami material, numerical simulations illustrated how it can be optimised for specific impact velocity regimes between 10-150 m/s. Practical design tools were then developed based on these results.