Empowering the smart grid : can redox batteries be matched to renewable energy systems for energy storage?

The charging of an undivided cerium–zinc redox battery by various current waveforms some of which mimic the output of renewable energy (solar, wind, tidal, biofuel burning) to electricity transducers is considered in this work, where the battery operates through diffusion-only conditions, and is discharged galvanostatically. Under reasonable assumption, the mathematical model developed enables the observation that the performance characteristic of the cells charged with a constant power input differentiates between the various current–charge waveforms, with cell geometry and electrode kinetics playing subtle, but significant, roles; in particular, high efficiency is observed for sunlight-charged batteries which are thin and suffer no corrosion of the sacrificial electrode, and which have already experienced a charge–discharge cycle. The performance characteristics of the systems are interpreted in the light of consequences for smart grid realisation, and indicate that, for a constant power input, the most matched renewable is biofuel burning with a current output that linearly increases with time.

Characteristics evaluation of an LMI-synthesis H∞ controller for a superconducting magnetic energy systems applied in power systems

© 2015 IEEE.This paper presents an H« controller synthesised based on linear matrix inequalities (LMI) for a current source converter based superconducting magnetic energy systems (SMESs) connected to a node of power systems where the regulation of grid current has considered as a control objective. To facilitate the control design, the system is represented in terms of state space realization with uncertainties. The control design involves selecting proper weighting functions and performing LMI-synthesis. The controller order is reduced by Henkel-norm method. Simulations are carried out to evaluate the characteristics of the controller under parametric uncertainties. It is found out that the proposed controller is inherently stable, possesses significantly small tracking error, and preserves robust performance for the SMES.

A novel operation and control strategy for a standalone hybrid renewable power system

This paper proposes a novel operation and control strategy for a renewable hybrid power system for a standalone operation. The proposed hybrid system consists of a wind turbine, a fuel cell, an electrolyzer, a battery storage unit, and a set of loads. The overall control strategy is based on a two-level structure. The top level is the energy management and power regulation system. Depending on wind and load conditions, this system generates reference dynamic operating points to low level individual subsystems. The energy management and power regulation system also controls the load scheduling operation during unfavorable wind conditions under inadequate energy storage in order to avoid a system blackout. Based on the reference dynamic operating points of the individual subsystems, the local controllers control the wind turbine, fuel cell, electrolyzer, and battery storage units. The proposed control system is implemented in MATLAB Simpower software and tested for various wind and load conditions. Results are presented and discussed.

Power demand and energy usage of container crane - comparison between AC and DC drives

The electrical data of two quay cranes, one has a DC drive system and the other has an AC drive system, in actual working conditions at a container terminal are measured and presented in this paper. Peak demand, energy usage, power factor and power quality are examined and compared.

Incorporation of a hybrid cooling system in water cooled power stations to reduce water and energy consumptions

Water shortage is a major problem facing the power industry in many nations around the world. The largest consumer of water in most power plants is the wet cooling tower. To assist water and energy saving for thermal power stations using conventional evaporative wet cooling towers, a hybrid cooling system is proposed in this paper. The hybrid cooling system may consists of all or some of an air pre-cooler, heat pump, heat exchangers, and adsorption chillers together with the existing cooling tower. The hybrid cooling system described in the paper, consisting of a metal hydride heat pump operating in conjunction with the existing wet cooling tower, is capable of achieving water saving by reducing the temperature of warm water entering the cooling tower. Cooler inlet water temperatures effectively reduce the cooling load on existing towers. This will ultimately reduce the amount of water lost to the air by evaporation whilst still achieving the same cooling output. At the same time, the low grade waste energy upgraded by the metal hydride heat pump, in the process of cooling the water, can be used to replace the bleed of steam for the lower stage feed heaters which will increase overall cycle efficiency.

Advancing architecture ecologies : energy principles in nature and urban systems

The search for a coherent approach to optimising the delivery of sustainable development has moved from rhetoric to reality, shaped by international drivers such as the UN Millennium Development Goal and the UN 'Decade of Education for sustainable development 2005- 2014'. Emphasis has been recently placed by Governmental bodies on creativity and innovation as a way to promote and sustain the social, cultural and economic well-being. This has led to, amongst other things, the development of a series of new initiatives to promote sustainable development. There is still a lack of understanding of the impacts of sustainability on architecture and their associated and interrelated ecologies because, at least in part, there is no significant joined up thinking regarding the implications of sustainability across the whole design, implementation and operation processes. There is a considerable challenge to ensure integration, cross-fertilisation and dissemination to provide meaningful outputs from the vast array of ecological systems with their differing structures. This paper explores the processes rather than products of ecological systems and possibilities for a credible integral system that guide sustainable development and advance architecture ecologies. The paper traces back the roots of the divorce between architecture profession and technology and highlights the importance of reaching back to the true meanings of Techne as key to develop integral sustainable systems. The paper underlines the energy principles that construct ecological principles and provide explanation of how such systems can be interpreted in the built environment. Enriching ecological culture is not a physical development or a large expensive projects but rather in a coherent and focused efforts by a group of professionals, academics, and practitioners with multi disciplinary talents to build a complex and multi facets of integral systems and ideas.

Power and discourse in information systems practice : a narrative research method

Relationships of authority and control and their effect on information systems actors has interested IS researchers since at least the 1980’s. The study of power itself has also troubled organisational and sociological theorists, from which information systems researchers have drawn various lines of attack. Our approach to power rests on an historical synchronic theory that seeks to uncover the places and operation of power through an examination of narrative ‘testaments’ which are analysed not from the perspective of the giving individual but from the structural elements of discourse that they may represent. This paper compliments previous research methods on the topic of power especially in expert reports and systems development methodologies; provides specific guidance on how to apply the notion of discourse synchronically; and reconstructs the commercial practice of information systems, not as a broad church, but as one of competing and epistemologically incommensurate discourse, where the fates of the powerful are balanced against the fearful and silent disciplined.

The relationship between repeated sprint ability and the aerobic and anaerobic energy systems

A large number of team games require participants to repeatedly produce maximal or near maximal sprints of short duration with brief recovery periods. The purpose of the present study was to determine the relationship between a repeated sprint ability (RSA) test that is specific to the energy demands of Australian Rules football (ARF), and the aerobic and anaerobic energy systems. 

The contribution of residential solar energy systems to the reduction of greenhouse gas emissions in the borough of Queenscliffe

The Borough of Queenscliffe has identified the importance of reducing its greenhouse gas emissions and aims to become a carbon zero municipality by 2020. For a house, suburb or town to become carbon neutral ideally it produces an equivalent amount of energy from renewable resources to that which it consumes. By increasing the number of solar systems, both photovoltaic (PV) and hot water, in the residential sector, greenhouse gas emissions will be reduced. The number of solar systems located in the Borough of Queenscliffe has been estimated and a database of these systems has been created, including the size and panel orientation. The energy generated by each solar system, in addition to the reductions in greenhouse gas emissions, has been calculated for an average year.

Development of distributed energy systems for Middle East Countries

Although Renewable energy applications in Middle East countries were started in the middle of the seventies, they have only gained momentum in the last ten years. Considering the past gained experience, a proposed national Renewable Energy (RE) plan aims toward bringing RE into the main stream of the national energy supply system with a target contribution of 10% of the electricity demand by the year 2020. The proposed plan calls for a wide spectrum of renewable energy applications. This paper will highlight renewable energy applications in Middle East countries, the gained experience, the RE resources, and the future prospects for the utilization of RE recourses.

Multi-agent approach for enhancing security of protection schemes in cyber-physical energy systems

This paper presents a distributed multi-agent scheme to detect and identify cyber threats on the protection systems of power grids. The integration of information and communication technologies (ICTs) into existing power grids builds critical cyberphysical energy systems CPESs) in which digital relays are networked cyber-physical components subject to various cyber threats. Cyber attacks on protection systems may mimic real faults, cause component failure, and disable the communication links. Agents utilize both cyber and physical properties to reinforce the detection technique and further distinguish cyber attacks from physical faults. This paper also introduces the problem of secure communicationprotocols and highlights the comparative studies for enhancing thesecurity of the protection systems. The proposed scheme is validatedusing a benchmark power system under various fault and cyber attack scenarios.

Managing complexity and insitutionalization : power and politics in ERP implementation in an Australian university

This chapter reports a case study of ERP implementation in an institution of higher education. The ERP is one based on integration of administrative tasks based on Oracle® systems and is successful both in terms of its embeddedness in institutionalized practice and in supporting that university's operations. The key issue that emerged from the study showed that understanding complexity, institutionalized practice, and the power relations in existence enable the implementation to be more effective, as it can be managed when understood. The chapter argues that organizations reproduce practice and that an ERP challenges that. To deal with that challenge, social dramas emerge wherever power exists, and the resulting conflicts challenge the effectiveness of the systems put in place. In this case study, the key role of the project champion in resolving the social dramas became evident.

Promoting and supporting requirements engineering creativity

Requirements Engineering (RE) is a commencing phase in the systems development life cycle and concerned with understanding and specifying the customer's requirements. RE has been recognized as a complex cognitive problem solving process which takes place in an unstructured and poorly understood problem .context. A recent understanding describes the RE process as inherently creative, involving cycles of incremental building followed by insight-driven econceptualization .of the problem space. This chapter relates this new understanding to various creative process models described in the creativity and psychology of problem solving literature.

A review of current attempts to support problem solving in RE using
various design rationale approaches suggests., that their common major
wealmess lies in the lack of support for the creative and insight-driven problem solving process in RE. In addressing this weakness, the chapter suggests a new approach to promoting and supporting RE creativity using design rationale. The suggested approach involves the ad hoc recording of rationale to support the creative exploration complemented by a post hoc conceptual characterization of the problem space to support insight driven reconceptualization.