Output list
Journal article
Economic assessment and the impact of policy instruments on electric two-wheelers in Vietnam
Published 2025
Energy for sustainable development, 87, 101742
This study analyzes the total cost of ownership (TCO) of electric two-wheelers (E2Ws) versus internal combustion engine two-wheelers (ICE-2Ws) in Vietnam, assessing their economic viability and adoption factors. It examines the impact of policy instruments like subsidies on affordability and market competitiveness while evaluating E2Ws' practicality in supporting Vietnam's clean energy transition. This study indicates that while E-Motorcycle has the highest TCO, followed by ICE-A motorcycles, E-Bikes have the lowest TCO. The E-motorcycle's high TCO indicates that premium electric models still face financial challenges in terms of overall affordability. Reduction in sticker price emerges as the most effective incentive, offering the largest decrease in TCO. Lower cost electric two-wheelers, such as E-Bikes, which have lower performance, are currently less expensive than two-wheelers running on internal combustion engines. Mid-range electric two-wheelers, such as E-Mopeds, which offer moderate performance, are priced similarly to manual motorbikes, the most popular model in Vietnam. Within the same segment, E2Ws offer better economic performance for owners compared to their ICE counterparts over time due to its lower fuel and maintenance costs accumulate and offset the battery replacement expenses. The analysis in this study indicates that while E2Ws are cost-effective for short-range travel, their economic viability diminishes with increasing travel distance due to lower fuel and maintenance costs accumulate and offset the battery replacement expenses. This underscores the need for targeted incentives and technological advancements to make E2Ws more competitive for broader use cases. Moreover, higher battery capacity helps reduce operating costs, significantly impacting the reduction of their TCO.
•E2Ws lower TCO over time, but high upfront costs hinder wider adoption.
Journal article
Published 2025
Energy conversion and management, 333, 119798
Given the urgent need to decarbonise the transport sector, a comprehensive analysis of alternative fuel technologies is essential. This study introduces an innovative freight transport model, incorporating a novel approach to calculating vehicle time costs, refuelling time, and energy intensity, applied to Australia’s freight sector. Findings indicate that under moderate development, battery electric vehicles gain a larger share in light commercial vehicles, while fuel cell electric vehicles dominate the truck segment. In high development scenarios, battery electric and fuel cell electric vehicles achieve closer parity across all vehicle types. The transition impacts refuelling infrastructure, with significant shifts in petrol and diesel station numbers, posing potential investment risks for diesel stations due to fluctuating demand across scenarios. High development scenarios highlight a substantial need for investment, driven by a surge in hydrogen station requirements and battery electric vehicle charger demand peaking at approximately 120,000 units in the internal combustion engine-ban scenario. Emission trends vary by scenario. Under reference and moderate development scenarios, total tank-to-wheel and well-to-wheel emissions increase over time. However, the internal combustion engine-ban and comprehensive scenarios lead to substantial emission reductions, underscoring the environmental significance of policy choices and technological advancements.
Journal article
Published 2025
Renewable & sustainable energy reviews, 218, 115811
Despite their vulnerability to climate change, mining and refining industries significantly provide energy transition materials. However, if no mitigation is implemented, the demand growth will increase direct and indirect emissions in the critical mineral sector. This research aims to comprehensively evaluate the decarbonisation agenda in lithium, nickel, and cobalt industries by profoundly examining the performances, strategies, and risks associated with climate transition. This study examines company reports of 27 players that accounted for at least half of the global lithium, nickel, and cobalt production. This study uses content analysis methodology to reveal patterns in decarbonisation targets, performances and practices. More than two-thirds of the observed companies favour onsite solar and wind generation. At least one-third of the samples mention energy-efficient equipment and electric vehicle adoption. Despite having a well-crafted strategy to reduce operational emissions, more efforts are needed to reduce the value-chain emissions. This study highlights the need for improvement in the carbon inventory and disclosure of scope three emissions by utilising artificial intelligence and maintaining strategic partnerships with stakeholders. Political, economic, social, technological, legal, and environmental (PESTLE) analysis also revealed patterns and linkages among the current decarbonisation challenges and opportunities, of which the industries are vulnerable to demand fluctuation, rising from regulatory and technological changes. This study highlights the current dynamics in the critical mineral supply chain, which may affect decarbonisation strategies in the industry. This study also provides a holistic approach to offer empirical practice for the industries, allowing them to tailor their strategies.
Journal article
Published 2025
Energy for sustainable development, 85, 101631
Recent global initiatives to increase renewable energy capacity have presented a pathway to simultaneously meet future electricity demands and achieve decarbonization. However, emerging economies have seen marginal growth partly because of ineffective energy policies enacted to propagate the adoption of these renewable energy technologies. Using Ghana as a case study, this research focused on assessing the impact of energy policies on deploying renewable energy technologies, specifically focusing on renewable energy-based hybrid mini-grids. The weighted sum multi-criteria decision and SWOT analysis methods were used to evaluate the policies' effectiveness. The results highlighted that numerous energy policies implemented across Ghana did not fully promote mini-grid development. The study showed that only the renewable energy master plan and the scaling-up renewable energy program had clearly defined strategies for mini-grid development. The study revealed that financial constraints, complex implementation strategies and limited monitoring mechanisms are the main reasons why the policies are ineffective in promoting the industry in Ghana.
Journal article
Electrifying Vietnam's streets: Identifying the determinants of electric two-wheelers uptake
Published 2024
Transportation research. Part D, Transport and environment, 129, 104116
This study analysed the key determinants driving Vietnam’s electric two-wheeler (E2W) market and proposes strategies to foster its growth. Using a multifaceted research approach, combining expert interviews and comprehensive consumer surveys involving 385 respondents. The study adopts the relative importance index for data analysis, highlighting the paramount significance of reliable charging infrastructure, upfront purchase costs, and reduced emissions. Additionally, E2Ws are favoured by sustainable design, modern aesthetics, simplified licensing, and purchase incentives that facilitate its adoption. Other primary considerations include technological aspects, such as safety, range, battery lifespan, and charging duration. Analysis of 15 expert interviews using NVivo software reveals the suitability of E2Ws for Vietnam's dense urban roads, economic advantages, and environmental priorities. While there's excitement about E2Ws, obstacles like climate impact, financial barriers, and infrastructure gaps remain. The research concludes with recommendations for promoting E2W adoption, emphasizing awareness drives, policy clarity, safety protocols, and technological advancements.
Journal article
Empowering Low-Income Communities with Sustainable Decentralized Renewable Energy-Based Mini-Grids
Published 2023
Energies, 16, 23, 7741
With less than seven years before the UN’s Sustainable Development Goals deadline, the race is on to achieve universal access to affordable, reliable and modern energy services in low-income communities in developing countries. These communities are mostly distant from central grids and economically suitable for off-grid mini-grid systems. Data suggest that these mini-grids are not sustained and often fail after a few years of operation. The authors investigated the challenges of an existing mini-grid system in Ghana and proposed measures to overcome them. Field surveys with expert stakeholders and users of the system were conducted to examine the challenges. The results showed that 98% of the residents use power for domestic purposes. The inability to pay for the power consumed was the highest-ranked challenge the users faced followed by power quality issues. From the expert stakeholders’ perspectives, economic challenges were the most significant barriers with a mean score range of 3.92 to 4.73 on a 1–5 Likert scale, followed by political challenges. The researchers propose that implementers must optimize non-hardware costs and promote local component manufacturing to address these economic challenges. In addition, we suggest that the government review the government-driven policy and involve the private sector.
Journal article
Drivers and challenges of off-grid renewable energy-based projects in West Africa: A review
Published 2023
Heliyon, 9, 6, e16710
Off-grid hybrid power systems with renewable energy as the primary resource remain the best option to electrify rural/remote areas in developing countries to help attain universal electricity access by 2030. However, deploying these systems in West Africa faces several challenges and regularly fail to transition from pilot, donor-sponsored projects to sustainable large-scale implementations. The study examined the drivers and challenges by conducting a review of previous studies done in the region and a short survey in Ghana. Using Political, Economic, Social, Technical, Legal and Environmental dimensions, the review and survey showed that economic challenges have the worst impacts on the sustainable development of off-grid renewable energy-based power systems in WA. Further, the analysis revealed patterns and linkages among the challenges that make it detrimental to focus solely on the most pressing challenges.
Journal article
Published 2023
Energy policy, 180, 113663
Transition to a low carbon economy has a unique set of circumstances which present both challenges and opportunities for the development of its energy policies and require customised energy planning solutions and policies. Each country begins its path to decarbonization from a different starting point. The Northern Territory (NT) of Australia has one of the highest rates of solar insolation in Australia which can be a catalyst for future energy development. This study explores the potential for long-range renewable energy (RE) planning and climate policies for the NT to transition to a low-carbon economy by 2050, while achieving sustainable economic growth by analysing three scenarios: business-as-usual (BAU), High Industry Growth (HIG) and Renewable Energy Export (REE). The results showed that slight variations in inputs and assumptions can affect the need and timing of appropriate policies to support a desired outcome or goal. In conclusion, a low-emissions economy based on an industry powered by renewable energy is possible with the support of a range of effectively timed energy and climate policies. Effective energy transition policies would need to be developed with careful consideration of the unique circumstances and existing barriers in the NT. The future could be a combination of elements in both HIG scenario and a REE scenario. If implemented and sequenced appropriately, energy policies can be effective in laying the groundwork for a smoother transition to low-carbon economy in the NT.
Journal article
Published 2022
Building and Environment, 209, Art. 108681
The concept of maintaining indoor environmental quality comprising building indoor temperature, relative humidity, CO2, and volatile organic compound (VOC) level poses new challenges to the optimal operation of heating, ventilation and air-conditioning (HVAC) systems. While existing case studies demonstrate the energy-saving potentials for efficient HVAC operation, there is a lack of studies quantifying energy savings whilst considering indoor environmental conditions. This study proposes a state-of-the-art modelling and optimization approach to minimize the energy consumption of the HVAC systems without compromising indoor environmental quality. While the primary objective of ensuring optimal operation of HVAC systems is to minimize energy consumption, controlling indoor environmental parameters to remain within the acceptable range imposes excess energy use. These two conflicting objectives constitute a multi-variable constrained optimization problem that has been solved using a particle swarm optimization (PSO) algorithm. Real-time predictive models are developed for the individual indoor environmental parameters and HVAC energy consumption using a Nonlinear Autoregressive Exogenous (NARX) neural network (NN). During model development, models' performance is optimized in terms of complexity, predictive accuracy, and ease of application to a real system. The proposed predictive models are then optimized to provide an optimal control setting for the HVAC systems considering seasonal variations. The results indicate that it is possible to reduce 7.8% of total energy, without negotiating indoor environmental conditions, e.g., air temperature 19.60–28.20°C and relative humidity 30–65% as per ASHRAE Standard 55, and CO2 ≤ 800 ppm and VOC ≤1000 ppm as per AS 1668.2.
Journal article
Published 2022
Solar Energy, 245, 231 - 253
The world’s energy systems are transforming rapidly and switching from fossil fuels to renewables to address the current emission reduction targets. With the decrease in the cost of solar PV module globally by about 55% since 2013, the uptake of solar PV has increased dramatically. As these modules are exposed to ambient conditions in the field, they can develop defects or faults. These defects can affect the output power of the PV module and overall system output. To mitigate this, early and easy detection of defects is considered critical for operation and maintenance. Some defects can be easily identified through the infrared (IR) imaging and the presence of hot-spots on the PV module. This study highlights the best operational and environmental conditions for conducting IR imaging of PV module to detect defects. This study reveals that hot-spots with a minor temperature difference of 1.3–1.4 °C compared to the adjacent healthy cells likely indicate the presence of internal defects such as shunt. These hot-spots only appeared at lower irradiance conditions irrespective of the cloud condition. The IR imaging on partially and cloudy days showed that the presence of intermittent clouds, high ambient temperature and low wind speed helps the detection of these internal defects in the PV module.