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[en] Several electrochemical energy storage batteries are under development for bulk energy storage. These batteries are often characterized by their low power density, but are attractive as stationary storage devices for load leveling and solar applications because of their potentially low cost. 17 refs
[en] The Dutch distribution companies are organised in the umbrella organization 'EnergieNed'. Amongst economics, environmental issues, marketing and legal issues, EnergieNed controls a research program. Part of this program is the energy storage program. Main task of the distribution companies is to supply the end-user with electricity, at the contracted price and quality. Storage might be a tool to achieve this. (author)
[en] This paper describes a concept for recovering the electrical energy remaining in an inductive energy storage system, such as that left in the barrel of a railgun after the projectile has exited the gun. Previously discussed recovery schemes usually involved the use of a capacitor bank that is capable of storing all the energy to be recovered. In this paper, the authors describe a circuit that recovers the energy in multiple parcels, each being a small fraction of the overall energy. This concept, herein referred to as multicycle resonant energy recovery, therefore allows for a significant reduction in the size and weight of the intermediate energy storage elements. The basic circuit and its operation are discussed as well as criteria for component selection, scaling, and tradeoffs. Results from a computer simulation of the energy recovery circuit applied to a railgun model are presented
[en] The purpose of the invention is to improve reliability of operation by increasing noise immunity of control circuits of adjustable spark gaps. Improvement of reliability is achieved due to the following: conductors of coaxial line are short-circuited from one end by a solid conductor; the internal conductor of the line is hollow, and a closed magnetic core is located on it from the side of short-circuited end; circuits of triggered spark-gap are located inside the hollow electrode. 2 figs
[en] Rapid development of smart electronics, energy harvesting technologies are gaining tremendous attention to provide alternative energy for self-powered operations of wearable electronics, sensors, wireless networks and medical implants, followed by substantial interest from both academia and industry. In this framework, piezoelectric nanogenerator (PNG) is an energy harvesting device that converts ubiquitous mechanical energy (such as vibration, walking, body movement, keyboard typing etc.) available in our surroundings, into a faun of electrical signal based on the energy conversion by nanostructured piezoelectric materials. Thus issues associated with conventional battery systems such as limited life-span, large size, environmental pollution, compatibility and cost intensively are mitigated by harvesting solutions
[en] Highlights: • An automated search for reaction systems suitable for thermochemical energy storage was performed. • Algorithm to build reaction systems for thermochemical energy storage is presented. • Close to 1000 possible reaction systems for 5 different reactive gases were found. • The VIENNA TCES-database for thermochemical energy storage materials is presented. - Abstract: Thermochemical energy storage (TCES) is considered as an emerging green technology for increased energy utilization efficiency, thereby achieving a reduction of greenhouse gases. Various reaction systems based on different substance classes (e.g. hydrates, hydroxides, oxides) were suggested and investigated so far. Nevertheless, the number of know reactions which are suitable is still limited, as the main focus concentrates on the investigation of a handful known substances, their further improvement or applicability. To find novel promising candidates for thermochemical energy storage and also to allow for a broader view on the topic, this work present a systematic search approach for thermochemical storage reactions based on chemical databases. A mathematical search algorithm identifies potential reactions categorized by the reactant necessary for the reaction cycle and ranked by storage density. These candidates are listed in the online available VIENNA TCES-database, combined with experimental results, assessing the suitability of these reactions regarding of e.g. decomposition/recombination temperature, reversibility, cycle stability, etc.
[en] The dc electrical requirements of the PEP magnets fall mainly into two categories: high power and current of single polarity and low- power bi-polar. The first category will be thyristor-chopper controlled off common 600 V dc busses. The second group will utilize continuously controlled push-pull transistor actuators. This paper discusses these categories. 1 ref., 2 figs
[en] PBFA II is a 100 TW pulsed power accelerator being constructed for use in the Light Ion Fusion Program. The objective of PBFA II is to accelerate and focus upon an ICF target a lithium beam with sufficicent energy, power, and power density to perform ignition scaling experiments. The technologies used in PBFA II include: (1) primary energy storage and compression with 6 MV, low-inductance Marx generators, (2) pulse forming in water-insulated, water-dielectric lines with self-closing water switches, (3) module synchronization using laser-triggerred, 6 MV multistage gas switches, (4) voltage addition in vacuum using self-magnetically-insulated biconic transmission lines, (5) inductive energy storage and pulse compression using a fast-opening plasma erosion switch, (6) beam formation using a magnetically-insulated ion diode, and (7) space charge and current neutralized beam propagation to the target in a gas-filled cell. Presently, accelerator construction is nearing completion, with the first multimodule shot expected by the end of January 1986
[en] In this study we deal with the methods and applications of describing, assessing and using thermal energy storage systems, as well as economical, energy conservation and environmental aspects of such systems. The energetic and environmental impacts of thermal energy storage (TES) systems are discussed and highlighted with a number of illustrative examples. The main emphasis is laid on sensible TES, since it is internationally accepted as the most economical and practical energy storage technique. An energy and exergy modelling is presented for TES systems as a key component in the above-mentioned aspects. Illustrative examples are also given to practically demonstrate how exergy analysis provides a more realistic and meaningful assessment than the conventional energy analysis of the efficiency and performance of a sensible heat storage system. It is believed that the results will be useful to engineers and designers seeking to improve and optimize TES systems. (author)
[en] Highlights: • Novel analysis of unique building with integrated pumped hydro energy storage system. • Full parameterisation of pumped hydro energy storage in buildings. • Feasibility of pumped hydro energy storage in buildings is studied. • Conditions for a better competitiveness of this technology are discussed. - Abstract: The growing use of variable energy sources is pushing the need for energy storage. With Pumped Hydro Energy Storage (PHES) representing most of the world’s energy storage installed capacity and given its maturity and simplicity, the question stands as to whether this technology could be used on a smaller scale, namely in buildings. In this paper, the feasibility of such an installation is analysed by modelling each one of its components and applying it to several installation scenarios. Proposed and existing installations are also reviewed, including a first-time analysis of an installation in France, which is presumably the only existing building with an integrated PHES system. It was found that the economies of scale that render large PHES installations competitive are not present in small installations. This limitation, associated to other important disadvantages, such as the large volume required, seem to point out PHES as an ill-suited solution for energy storage in buildings, an important finding for building design and energy policy. Nevertheless, if synergies with existing reservoirs could be found (for example for a building on a riverside), costs could be significantly lowered. Further research on possible synergies with other building systems as well as a life-cycle assessment analysis are recommended.