A computational framework for uncertainty integration in stochastic unit commitment with intermittent renewable energy sources

The penetration of intermittent renewable energy sources (IRESs) into power grids has increased in the last decade. Integration of wind farms and solar systems as the major IRESs have significantly boosted the level of uncertainty in operation of power systems. This paper proposes a comprehensive computational framework for quantification and integration of uncertainties in distributed power systems (DPSs) with IRESs. Different sources of uncertainties in DPSs such as electrical load, wind and solar power forecasts and generator outages are covered by the proposed framework. Load forecast uncertainty is assumed to follow a normal distribution. Wind and solar forecast are implemented by a list of prediction intervals (PIs) ranging from 5% to 95%. Their uncertainties are further represented as scenarios using a scenario generation method. Generator outage uncertainty is modeled as discrete scenarios. The integrated uncertainties are further incorporated into a stochastic security-constrained unit commitment (SCUC) problem and a heuristic genetic algorithm is utilized to solve this stochastic SCUC problem. To demonstrate the effectiveness of the proposed method, five deterministic and four stochastic case studies are implemented. Generation costs as well as different reserve strategies are discussed from the perspectives of system economics and reliability. Comparative results indicate that the planned generation costs and reserves are different from the realized ones. The stochastic models show better robustness than deterministic ones. Power systems run a higher level of risk during peak load hours.

Identifying the determinants of renewable energy consumption in leading renewable energy investor emerging countries

This article analyses the determinants of renewable energy consumption in six major emerging economies who are proactively accelerating the adoption of renewable energy. The long-run elasticities from both panel methods (fully modified ordinary least square and dynamic least square) and the time series method (autoregressive distributed lag) seem to be pretty consistent. For Brazil, China, India and Indonesia, in the long-run, renewable energy consumption is significantly determined by income and pollutant emission. However, for Philippines and Turkey, income seems to be the main driver for renewable energy consumption. In the short-run, for Brazil and China bi-directional causalities between renewable energy and income; and between renewable energy and pollutant emission are found. This research justifies the efforts undertaken by emerging countries to reduce the carbon intensity by increasing the energy efficiency and substantially increasing the share of renewable in the overall energy mix

A decentralised multi-agent approach to enhance the stability of smart microgrids with renewable energy

This paper presents the impact of large penetration of wind power on the transient stability through a dynamic evaluation of the critical clearing times (CCTs) by using intelligent agent-based approach. A decentralised multi-agent-based framework is developed, where agents represent a number of physical device models to form a complex infrastructure for computation and communication. They enable the dynamic flow of information and energy for the interaction between the physical processes and their activities. These agents dynamically adapt online measurements and use the CCT information for relay coordination to improve the transient stability of power systems. Simulations are carried out on a smart microgrid system for faults at increasing wind power penetration levels and the improvement in transient stability using the proposed agent-based framework is demonstrated.

Renewable energy integration : challenges and solutions

This book presents different aspects of renewable energy integration, from the latest developments in renewable energy technologies to the currently growing smart grids. The importance of different renewable energy sources is discussed, in order to identify the advantages and challenges for each technology. The rules of connecting the renewable energy sources have also been covered along with practical examples. Since solar and wind energy are the most popular forms of renewable energy sources, this book provides the challenges of integrating these renewable generators along with some innovative solutions. As the complexity of power system operation has been raised due to the renewable energy integration, this book also includes some analysis to investigate the characteristics of power systems in a smarter way. This book is intended for those working in the area of renewable energy integration in distribution networks.

Optimal coordination of G2V and V2G to support power grids with high penetration of renewable energy

Electric vehicles (EVs) have recently gained much popularity as a green alternative to fossil-fuel cars and a feasible solution to reduce air pollution in big cities. The use of EVs can also be extended as a demand response tool to support high penetration of renewable energy (RE) sources in future smart grid. Based on the certainty equivalent adaptive control (CECA) principle and a customer participation program, this paper presents a novel control strategy using optimization technique to coordinate not only the charging but also the discharging of EV batteries to deal with the intermittency in RE production. In addition, customer charging requirements and schedules are incorporated into the optimization algorithm to ensure customer satisfaction, and further improve the control performance. The merits of this scheme are its simplicity, efficiency, robustness and readiness for practical applications. The effectiveness of the proposed control algorithm is demonstrated by computer simulations of a power system with high level of wind energy integration.

Novel design of a renewable energy remote laboratory

BACKGROUND OR CONTEXT: Current work in remote laboratories focuses on student interaction in a setting that can be at times disconnected from real world systems. Laboratories have been developed that show models of a working system, focusing on a single aspect, but very few laboratories allow the user to see the outputs of a working system that interacts with the real world as would be expected outside of a laboratory setting. It was aimed with this paper to show a design of a novel approach to building a remote laboratory that would be able to interact with a fully functional renewable energy system, and to show the students the outputs of such a system in real time. It allows for the user to be presented with information in a new context.
PURPOSE OR GOAL: With this research it is hoped to achieve a remote laboratory that will be able to present students with the data from a renewable energy system live, as it is generated as well as all the logged date generated. It is aimed with this novel approach to building a remote laboratory to assist the students in learning about renewable energy systems while allowing the student to access real data, instead of simulated data. Links to increased motivation due to realism in data given as well as change in student perception on learning in remote laboratories mean that a system such as this could change the way students approach learning about renewable energy generation systems. This will require further research however.
APPROACH: This remote laboratory required gathering data from an already established system. The live results were not recorded, and a log file was generated daily, however this was not fast enough to give to students as it was generated, so a system that could maintain communication between all systems, while also polling for data itself was required. In addition to this, the system had to communicate to a server that would give students access to the live data. The server was set up in such a way that students were not required to install any programs on their computer, multiple students could access the data at any given time, and a wide range of devices, including mobile devices, could all access the remote laboratory.
DISCUSSION: Key outcomes include the design of the remote laboratory, including screenshots of data acquisition from the renewable energy system from different devices. The design is split into two sections, one covering the server side architecture while another covers the data acquisition architecture. A very brief discussion on students’ initial interaction is also undertaken.
RECOMMENDATIONS/IMPLICATIONS/CONCLUSION: Research has shown that the degree of realism in remote education can have an effect on students’ behaviors/motivation in a remote laboratory. By allowing students to knowingly access a real system that is currently being used to generate power from renewable energy sources, the methods and motivations that students use when approaching renewable energy systems may change.

Tailoring enzymes for biofuel production with reference to Australian biomass

Manufacture of biofuels from existing biomass may provide a sustainable alternative to the extensive utilization of fossil fuels. Biomass offers environmental advantage over fossil fuels as it is a renewable energy source with low sulphur and nitrogen content and is carbon neutral over its production and utilization. Ranges of biomass are reported worldwide to be suitable raw material for bioethanol production. These can be generally classified into three groups; sucrose based (sugar cane), starch based (corn, wheat and barley) and lignocellulosic (which is mostly comprised of lignin, cellulose and hemicelluloses in grasses, wood and straw) materials. However, the limited supply of two biomass groups (sucrose and starch) will not satisfy society’s growing energy demands; thus biofuel technology based on lignocelluloses is under intense investigation. The main bottleneck in lignocellulosic biomass conversion for biofuel production is the enzymatic depolymerisation of cell wall polysaccharides into fermentable sugars. Protein engineering has recently been used to improve the performance of lignocelluloses degrading enzymes, as well as proteins involved in biofuel synthesis pathways. We have produced a recombinant enzyme that has the ability to produce monomeric sugars from a complex substrate. This presentation will summarize current efforts to develop an enzymatic treatment which would facilitate the economical processing of biomass available in Australia for bioenergy generation.

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.

Performance evaluation of 3D printed miniature electromagnetic energy harvesters driven by air flow

As a renewable and non-polluting energy source, wind is used to produce electricity via large-diameter horizontal or vertical axis wind turbines. Such large wind turbines have been well designed and widely applied in industry. However, little attention has been paid to the design and development of miniature wind energy harvesters, which have great potential to be applied to the HVAC (heating, ventilating and air conditions) ventilation exhaust systems and household personal properties. In this work, 10 air-driven electromagnetic energy harvesters are fabricated using 3D printing technology. Parametric measurements are then conducted to study the effects of (1) the blade number, (2) its geometric size, (3) aspect ratio, presence or absence of (4) solid central shaft, (5) end plates, and (6) blade orientation. The maximum electrical power is 0.305 W. To demonstrate its practical application, the electricity generated is used to power 4 LED (light-emitting diode) lights. The maximum overall efficiency ηmax is approximately 6.59%. The cut-in and minimum operating Reynolds numbers are measured. The present study reveals that the 3D printed miniature energy harvesters provide a more efficient platform for harnessing ‘wind power’.

Anaerobic treatment of juice and fruit-processing effluents

Effluents from the juice and fruit processing industries have high organic matter content. Discharge of these effluents without appropriate treatment would therefore have a negative impact on the environment. High organic contents and low contamination levels make such effluents suitable for biological treatment, especially anaerobic digestion. In the latter process, significant amounts of digester gas can be produced, turning a waste stream into a source of renewable energy that can be used for electricity and heat production, leading to financial benefits.This paper investigates the feasibility of anaerobic digestion and the gas generation potential of five different effluents from the carrot-juice, orange-juice and sultana processing industries. Benefits are assessed in terms of digester gas production and organic matter reduction. The results show that the specific gas production ranges between 665 and 860 m3 per tonne of effluent treated (as organic dry matter). Furthermore, nearly 100% of the organic matter is converted into gas in the case of the carrot- and orange-juice processing residues, while a 84.5% reduction of the organic matter was found to be achievable in the case of the sultana wastes. While these results are promising, further testing will be required to validate them in a larger scale.

Towards the renewable relocatable classroom

Relocatable or temporary classrooms are now a common sight in our school grounds. Despite their name, they tend to become permanent structures, due to the limited funding for traditional "bricks and mortar" school buildings. Unfortunately, the designs used for relocatables do not reflect current best practice in energy efficient design. Consequently, they can be either energy hungry and/or thermally uncomfortable, depending on the level of conditioning equipment installed. Opportunities exist to apply solar design principles to the standard relocatable classroom. This paper explores the possibilities of reducing energy consumption to such a le\A31 that the remaining energy could then be supplied to the relocatable classroom from renewable energy technologies

Use of renewable building materials in residential construction : a review

The development of mass-produced environmentally-benign housing is one of the critical factors in the transition to global sustainability. Such housing will need to be constructed from renewable and/or recycled materials, be conditioned using minimal or no non—renewable energy, and be affordable. The universal need for such built environment resource stewardship is urgent. In developing countries, the requirement is to shelter growing populations, and in industrialised countries, there is a need for an alternative to the current resource and nergy-intensive material usage in housing. While there are some good surveys of building materials made from renewable resources, such as the BEDP Environment Design Guide Pro 11 by Gelder (2002), there does not appear to be a comprehensive database of these materials linked to abundant and reliable supply. This paper reviews the current availability and potential usage of renewable materials applicable to Australian mainstream residential construction. It concludes that the current state of publicly available information is dispersed and embedded in multiple sources with variance in detail, incomplete access and uncertain comparison across the sources.

Development of a building integrated photovoltaic/thermal solar energy cogeneration system

Using renewable energy sources for onsite cogeneration from structural building elements is a relatively new concept and is gaining considerable interest. In this study the design, development, manufacturing and testing of a novel building integrated photovoltaic/thermal (BIPVT) solar energy cogeneration system is discussed.

Adhesives (ADH), resistance seam welding (RSW) and autoclaving (ATC) were identified as the most appropriate for fabricating BIPVT roofing panels. Of these manufacturing methods ADH was found to be most suitable for low volume production systems due to its low capital cost.

A prototype panel, fabricated using ADH methods, exhibited good thermal performance. It was also shown that BIPVT performance could be theoretically predicted using a one dimensional heat transfer model and showed excellent agreement with experimental data. The model was used to suggest further design improvements. Finally, a transient simulation of the BIPVT was performed in TRNSYS and is used to illustrate the benefits of the system.

An energy-autonomous home in Melbourne - myth or reality?

Energy-autonomous buildings are possible. Completely energy self-sufficient houses can be found, for example, in Europe. If it is possible to cover the entire energy demand of a household from only renewable energy generated on site in a central European climate, what is required in a temperate climate, typical of southern Australia? This paper describes an investigation to broadly assess the technical, practical and financial feasibility of energy-autonomy for a hypothetical suburban house in Melbourne, Victoria. The findings firstly demonstrate the importance of reducing energy demand by using passive solar building strategies and energy efficient appliances to reduce demand to a reasonable level. The paper then discusses four scenarios and combinations of technologies to meet this reduced demand. The three scenarios which give energy autonomy increase the capital cost of a typical house by between 15% and 3%, and there would be insufficient roof area to accommodate the solar technologies required in two of the scenarios investigated. It is therefore concluded that while the goal of energy autonomy is technically feasible, it is not likely to be financially or practically acceptable. A fourth scenario of an energy-exporting house was also investigated and is shown to be a much more attractive option.