Output list
Journal article
Published 2023
Energies, 16, 7
Virtual power plants (VPPs) are an effective platform for attracting private investment and customer engagement to speed up the integration of green renewable resources. In this paper, a robust bidding strategy to participate in both energy and ancillary service markets in the wholesale electricity market is proposed for a realistic VPP in Western Australia. The strategy is accurate and fast, so the VPP can bid in a very short time period. To engage customers in the demand management schemes of the VPP, the gamified approach is utilized to make the exercise enjoyable while not compromising their comfort levels. The modelling of revenue, expenses, and profit for the load-following ancillary service (LFAS) is provided, and the effective bidding strategy is developed. The simulation results show a significant improvement in the financial indicators of the VPP when participating in both the LFAS and energy markets. The payback period can be improved by 3 years to the payback period of 6 years and the internal rate of return (IRR) by 7.5% to the IRR of 18% by participating in both markets. The accuracy and speed of the proposed bidding strategy method is evident when compared with a mathematical method.
Journal article
Grid-Forming virtual power plants: Concepts, technologies and advantages
Published 2022
Energies (Basel), 15, 23, Art. 9049
Virtual Power Plants (VPPs) are efficient structures for attracting private investment, increasing the penetration of renewable energy and reducing the cost of electricity for consumers. It is expected that the number of VPPs will increase rapidly as their financial return is attractive to investors. VPPs will provide added value to consumers, to power systems and to electricity markets by contributing to different services such as the energy and load-following services. One of the capabilities that will become critical in the near future, when large power plants are retired, is grid-forming capability. This review paper introduces the concept of grid-forming VPPs along with their corresponding technologies and their advantages for the new generation of power systems with many connected VPPs.
Journal article
Published 2021
Energies, 14, 4, Article 1113
To integrate large-scale renewable energy into energy systems, an effective participation from private investors and active customer engagement are essential. Virtual power plants (VPPs) are a very promising approach. To realize this engagement, an efficient monitoring and control system needs to be implemented for the VPP to be flexible, scalable, secure, and cost-effective. In this paper, a realistic VPP in Western Australia is studied, comprising 67 dwellings, including a 810 kW rooftop solar photovoltaic (PV) system, a 700 kWh vanadium redox flow battery (VRFB), a heat pump hot water system (HWS), an electric vehicle (EV) charging station, and demand management mechanisms. The practical and detailed concept design of the monitoring and control system for EEBUS-enabled appliances, and also for the PV and VRFB system, with smart inverters, is proposed. In addition, a practical fog-based storage and computing system is developed to enable the VPP owner to manage the PV, VRFB, and EV charging station for maximizing the benefit to the customers and the VPP owner. Further, the proposed cloud-based applications enable customers to participate in gamified demand response programs for increasing the level of their engagement while satisfying their comfort level. All proposed systems and architecture in this paper have the capability of being implemented fully and relevant references for practical devices are given where necessary.
Journal article
Published 2020
Energies, 13, Article 2614
Achieving the renewable energy integration target will require the extensive engagement of consumers and the private sector in investment and operation of renewable-based energy systems. Virtual power plants are an efficient way to implement this engagement. In this paper, the detailed costs and benefits of implementing a realistic virtual power plant (VPP) in Western Australia, comprising 67 dwellings, are calculated. The VPP is designed to integrate and coordinate rooftop solar photovoltaic panels (PV), vanadium redox flow batteries (VRFB), heat pump hot water systems (HWSs), and demand management mechanisms. An 810-kW rooftop solar PV system is designed and located using the HelioScope software. The charging and the discharging of a 700-kWh VRFB are scheduled for everyday use over a year using an optimization algorithm, to maximize the benefit of it for the VPP owners and for the residents. The use of heat pump HWSs provides a unique opportunity for the residents to save energy and reduce the total cost of electricity along with demand management on some appliances. The cost-and-benefit analysis shows that the cost of energy will be reduced by 24% per dwelling in the context of the VPP. Moreover, the internal rate of return for the VPP owner is at least 11% with a payback period of about 8.5 years, which is a promising financial outcome.
Journal article
Comprehensive environmental impacts and optimization of onshore shale gas development and delivery
Published 2019
Energy Technology, 7, 5, Article number 1800871
The environmental impact of shale gas hydraulic fracturing is not completely understood. Therefore, the objective of this paper is to estimate the lifecycle environmental impact of shale gas production per mega joule (MJ) of energy extracted and delivered. The analysis is based on using CML 2001‐Apr 2015 methods in GaBi software on a case study of a shale gas well. The global warming potential (GWP100) ranges from 54 to 99 g CO2e /MJ with a central estimate of 72 g CO2e /MJ. The GWP 100, including land use change, is 230 g CO2e /MJ. The best‐case scenario, with no venting of the gas, has the minimum GWP 100 impact. Shale gas has a high marine ecotoxicity potential, among other environmental impacts. Bentonite contributes the most to the abiotic depletion potential elements impact. The frac water contributes the most to the freshwater aquatic ecotoxicity potential (FAETP) impact. Mercury (Hg) and radioactive elements (e.g., radon) are the major pollutants contributing to the terrestrial ecotoxicity potential impacts. The findings of this study can be used for optimization of the processes used by mining and exploration companies.
Journal article
Published 2018
Superlattices and Microstructures, 116, 27 - 35
Core-shell self-powered SiNWs homojunction photosensors have been fabricated. SiNWs are prepared by a metal assisted chemical etching method using different HF/H2O2 ratios and etching times. The length of the p-SiNWs increased as the H2O2 concentration and etching time increased. All the grown SiNWs show very low (∼0.7%) optical reflectance for the wavelength range of 200–1100 nm. Photoluminescence spectra of all prepared SiNWs show sharp and broad emission bands located in the red region of the light spectrum. Core-shell homojunction photosensors were fabricated by spin coating P2O2 onto the surface of the prepared p-SiNWs and annealed at 900 °C for 1 h. The fabricated devices exhibited photovoltaic behavior and high photosensitivity with fast response speed to the visible light. However, the sample that was fabricated using HF/H2O2 ratio of 1:1 showed the highest photosensitivity value of 3578% while the photosensor prepared using 2:1 ratio of HF/H2O2 gave the faster rise and decay time.
Journal article
State of the environment reporting in Western Australia: law, land and beyond
Published 2018
Australasian Journal of Environmental Management, 25, 4, 371 - 384
State of the environment (SoE) reporting has been in place in the majority of Australian jurisdictions since the early 1990s. Over the past decade, the process has stalled in Western Australia (WA) and, at present, shows no sign of reappearing. This is all the more serious since the degraded condition of the state’s environment calls out for regular review, analysis and action. We place this in a wider framework by (a) considering the significance of SoE reporting as a matter of collective responsibility, (b) mapping out a program of necessary legislative reform for WA and (c) outlining the challenges confronting SoE reporting as an act of public communication. Our thesis throughout is that SoE reporting combines ethical, democratic and environmental dimensions, and that the significance of WA’s withdrawal from the process can only be understood in this context.
Journal article
Published 2018
Silicon, 10, 2, 403 - 411
A photosensor was fabricated based on a lead sulfide (PbS)/porous silicon (Ps) heterojunction. An n-type Si(100) single crystal wafer was used to prepare the Ps using a photo-electrochemical etching method. A PbS nanocrystalline thin film was deposited onto the Ps substrate using a microwave-assisted chemical bath deposition (MA-CBD) technique. The current-voltage (I-V) characteristics of the fabricated PbS/Ps photosensor were studied under dark, 10 mW/cm2, 20 mW/cm2, and 40 mW/cm2 illumination by light. The device shows good response to light even without a bias voltage and the sensitivity when the applied voltage is 0 V decreased from 5.66 × 104 % under 10 mW/cm2 to 1.8 × 103 % when the device is illuminated by 40 mW/cm2 intensity light. The fabricated PbS/Ps photdetector shows a faster response to light of 0.43 sec when the applied voltage and intensity of light were 1.0 V and 40 mW/cm2, respectively. Moreover, the fastest fall time was 0.4 sec obtained for the device that was exposed to 40 mW/cm2 light and biased by 0.75 V.
Journal article
Published 12/2017
Renewable Energy, 113, 713 - 731
An interactive web tool was created to simulate 100% renewable electricity supply scenarios for the South-West Interconnected System (SWIS) in the south-west of Western Australia. The SWIS is isolated from other grids and currently has no available hydropower. Hence it makes a good case study of how supply and demand might be balanced on an hour-by-hour basis and grid stability maintained without the benefit of energy import/export or pumped hydroelectric storage. The tool included regional models for wind and solar power, so that hypothetical power stations were not confined to sites with existing wind farms or solar power stations, or sites with measurements of wind speed and solar radiation. A generic model for solar thermal storage and simple models for energy efficiency, distributed battery storage and power to gas storage were also developed. Due to the urgency of climate change mitigation a rapid construction schedule of completion by 2030, rather than the more common target of 2050, was set. A scenario with high wind generation, and scenarios with varying levels of solar power, wind power, distributed battery storage, energy efficiency improvements and power to gas systems were considered. The battery storage system and PV arrays were configured to provide synthetic inertia to maintain grid stability (with a small loss in capacity for each), and existing synchronous generators were kept spinning with no fuel input, adding a small increase to the electrical load demand. The level of synthetic inertia provided by battery storage was estimated for each scenario. The results indicated that a balanced mix of solar PV, solar thermal, efficiency, and storage were the most feasible to be built on a rapid time scale. The required capacity and build rate of the generation and storage systems would be reduced if energy efficiency improvements were implemented on a more rapid schedule compared to the current global improvement rate. The scenario with very high levels of wind power (∼80% generation) were found to be capable of meeting SWIS reliability criteria if very large amounts of distributed storage or some high capacity seasonal reserve generation system such as power to gas were present. High levels of battery storage capacity and efficiency improvement could be as effective as a power to gas system. It was confirmed that all scenarios provided the same or greater levels of inertia than presently provided by conventional generators. This tool showed that it is possible to examine renewable energy scenarios for regional electricity networks without high computing power.
Journal article
Sustainable energy education: addressing the needs of students and industry in Australia
Published 2017
Renewable energy and environmental sustainability, 2, 401-7
A survey has been carried out of graduates and employers working in the sustainable energy (SE) industry in Australia. The aims were to identify the key areas of content to be included in University level SE training and the type of degree structures that are most appropriate for SE professionals. Attention was also directed to the mode of instruction (online, blended or face-to-face) and the role of work-integrated learning (WIL). This paper presents the results of the survey, which provide guidance to Universities seeking to develop new, or revise existing, SE education offerings. The results of the survey clearly indicate that responding students and employers prefer a generalist degree in engineering, with a stream in sustainable energy as the initial qualification for professionals in this field. Specialist degrees at postgraduate level were also considered appropriate for continuing professional education (CPE). Both graduates and employers agreed on key areas to be included in the SE courses. These key areas are generic skills (research methods, team work, report writing), generation technologies (especially PV, wind and biomass), and enablers (such as economics, policy and project management). The graduates, many of whom came from overseas countries, generally agreed about the course content and its relevance to employment in their countries. Face-to-face or blended learning was preferred by both groups as the mode of instruction for the first degree. Online learning was considered a valuable adjunct in the undergraduate course and more suitable for CPE in postgraduate courses. WIL and more practical work were considered important, especially in the first degree. There was some disagreement about the appropriate length of work placements, with graduates preferring 6–8 weeks and employers 10–12 weeks. This work should provide a basis for further course development and curriculum reform for sustainable energy education.