• Energy Research

Biodiesel as an alternative to diesel fuel produced from vegetable oils or animal fats has attracted more and more attention because it is renewable and environmentally friendly. Compared to conventional diesel fuel, biodiesel has slightly lower performance in engine combustion due to the lower calorific value that leads to lower power generated. This study investigates the effect of multi-walled carbon nanotubes (MWCNTs) as an additive to the rice bran methyl ester (RBME). Artificial neural network (ANN) and response surface methodology (RSM) was used for predicting the calorific value. The interaction effects of parameters such as dosage of MWCNTs, size of MWCNTs and reaction time on the calorific value of RBME were studied. Comparison of RSM and ANN performance was evaluated based on the correlation coefficient (R2), the root mean square error (RMSE), the mean absolute percentage error (MAPE), and the average absolute deviation (AAD) showed that the ANN model had better performance (R2 = 0.9808, RMSE = 0.0164, MAPE = 0.0017, AAD = 0.173) compare to RSM (R2 = 0.9746, RMSE = 0.0170, MAPE = 0.0028, AAD = 0.279). The optimum predicted of RBME calorific value that is generated using the cuckoo search (CS) via lévy flight optimization algorithm is 41.78 (MJ/kg). The optimum value was obtained using 64 ppm of < 7 nm MWCNTs blending for 60 min. The predicted calorific value was validated experimentally as 41.05 MJ/kg. Furthermore, the experimental results have shown that the addition of MWCNTs was significantly increased the calorific value from 36.87 MJ/kg to 41.05 MJ/kg (11.6%). Also, the addition of MWCNTs decreased flashpoint (−18.3%) and acid value (−0.52%). As a conclusion, adding MWCNTs as an additive had improved the physicochemical properties characteristics of RBME. To our best knowledge, no research has yet been performed on the effect of multi-walled carbon nanotubes-additive in physicochemical property of rice brand methyl ester application so far.

Organic Rankine Cycle (ORC) power generation systems may be used to utilize heat source with low pressure and low temperature such as solar energy. Many researchers have focused on different aspects of ORC power generation systems, but none so far has focused on the patent landscape of ORC system applications. As such, the objective of this study is to identify published patents on ORC system applications, particularly for solar energy. Four (4) technologies were identified in ORC application for solar energy: parabolic dish, parabolic trough, solar tower, and linear Fresnel reflector. A methodical search and analysis of the patent landscape in ORC system applications for solar energy published between 2007–2018 was conducted using the Derwent Innovation patent database. From the approximately 51 million patents in the database from various countries and patent agencies, 3859 patents were initially identified to be related to ORC applications for solar energy. After further stringent selection processes, only 1100 patents were included in this review. From these 1100 patents, approximately 12% (130 patents) are associated with parabolic dishes, about 39% (428 patents) are associated with parabolic troughs, approximately 21% (237 patents) are associated with solar towers, and about 28% (305 patents) are associated with linear Fresnel reflectors. Published patents on solar tower technology are currently on an increasing trend, led by China. All of these patents were published in the past 11 years. From this study, further researches on ORC application are still ongoing, but ORC application for solar energy has the potential to advance; allowing the world to ease issues related to over-reliance on fossil fuel.

The COVID-19 pandemic has affected every sector in the world, ranging from the education sector to the health sector, administration sector, economic sector and others in different ways. Multiple kinds of research have been performed by research centres, education institutions and research groups to determine the extent of how huge of a threat the COVID-19 pandemic poses to each sector. However, detailed analysis and assessment of its impact on every single target within the 17 Sustainable Development Goals (SDGs) have not been discussed so far. We report an assessment of the impact of COVID-19 effect towards achieving the United Nations SDGs. In assessing the pandemic effects, an expert elicitation model is used to show how the COVID-19 severity affects the positive and negative impact on the 169 targets of 17 SDGs under environment, society and economy groups. We found that the COVID-19 pandemic has a low positive impact in achieving only 34 (20.12%) targets across the available SDGs and a high negative impact of 54 targets (31.95%) in which the most affected group is the economy and society. The environmental group is affected less; rather it helps to achieve a few targets within this group. Our elicitation model indicates that the assessment process effectively measures the mapping of the COVID-19 pandemic impact on achieving the SDGs. This assessment identifies that the COVID-19 pandemic acts mostly as a threat in enabling the targets of the SDGs.

The primary objective of this paper is to analyse the growth of energy-related CO2 emissions in ASEAN (Association of Southeast Asian Nations), with specific emphasis on identifying its trends and underlying drivers. This objective is premised on the arguments that: (1) there is a general lack of analysis of energy-related CO2 emissions growth across ASEAN countries; and (2) such an analysis is critical, because it could enable an assessment to be made of the efficacy of existing energy policies for reducing emissions. Decomposition analysis is the main approach adopted in this paper. The findings of this paper suggest that the growth of energy-related CO2 emissions has slowed in some major emitters in the region, due to energy efficiency improvement, and, to a lesser extent, a gradual switch in energy fuel mix towards lower emission sources (gas and renewables). However, this improvement is unlikely to drive a major transformation in the energy sectors of the region to the extent considered adequate for redressing the challenge of rising emissions, as indicated by a steady emissions growth in most ASEAN countries over the entire study period (1971–2016). By implication, this suggests that a significant scale-up of existing policy effort is needed to rectify the situations.

Abstract Exploring and improvement of biodiesel production from non-edible vegetable oil is one of the effective ways to solve limited amount of traditional raw materials and their high prices. The main objective of this study is to optimize the biodiesel production process parameters (methanol-to-oil ratio, agitation speed and concentration of the potassium hydroxide catalyst) of a biodiesel derived from non-edible feedstocks, namely Jatropha curcas and Ceiba pentandra, using response surface methodology based on Box–Behnken experimental design. Based on the results, the optimum operating parameters for transesterification of the J50C50 oil mixture at 60 °C over a period of 2 h are as follows: methanol-to-oil ratio: 30%, agitation speed: 1300 rpm and catalyst concentration: 0.5 wt.%. These optimum operating parameters gives the highest yield for the J50C50 biodiesel with a value of 93.33%. The results show that there is a significant improvement in the physicochemical properties of the J50C50 biodiesel after optimization, whereby the kinematic viscosity at 40 °C, density at 15 °C, calorific value, acid value and oxidation stability is 3.950 mm2/s, 831.2 kg/m3, 40.929 MJ/kg, 0.025 mg KOH/g and 10.01 h, respectively. The physicochemical properties of the optimized J50C50 biodiesel fulfill the requirements given in the ASTM D6751 and EN14214 standards.

This study is about the electrification of the remote islands in the Indian Ocean that were severely affected by the tsunami in the 2004 earth earthquake. To supply electricity to the islands, two diesel generators with capacities of 110 kW and 60 kW were installed in 2019. The feasibility of using renewable energy to supplement or replace the units in these two generators is investigated in this work. In 2019, two diesel generators with capacities of 110 kW and 60 kW were installed in the islands to supply electricity. This work analyses whether the viability of using renewable energy can be used to supplement or replace these two generators. Among the renewable energy options proposed here are a 100 kW wind turbine, solar PV, a converter, and batteries. As a result, the study’s goal is to perform a techno-economic analysis and optimise the proposed hybrid diesel and renewable energy system for a remote island in the Indian Ocean. The Hybrid Optimisation Model for Electric Renewable (HOMER) Pro software was used for all simulations and optimisation for this analysis. The calculation is based on the current diesel price of USD 0.90 per litre (without subsidy). The study found that renewable alone can contribute to 29.2% of renewable energy fractions based on the most optimised systems. The Net Present Cost (NPC) decreased from USD 1.65 million to USD 1.39 million, and the levelised Cost of Energy (CoE) decreased from 0.292 USD/kWh to 0.246 USD/kWh, respectively. The optimised system’s Internal Rate of Return (IRR) is 14% and Return on Investment (ROI) 10%, with a simple payback period of 6.7 years. This study shows that it would be technically feasible to introduce renewable energy on a remote island in Indonesia, where numerous islands have no access to electricity.

AbstractWith the ever‐increasing danger of climate change, power plants are shifting from polluting fossil fuels to sustainable bioenergy fuels. As Malaysia continues to pledge to decrease glasshouse gas (GHG) emissions, quick and dramatic action should resolve the reliance on fossil fuel power plants. Furthermore, the coal‐fired power station is Malaysia's biggest supplier of energy and the final power plant to be decommissioned. In Malaysia, a significant portion of palm oil biomass has the potential to replace coal in the generation of renewable energy power. However, the deployment of palm oil biomass as a renewable energy source has not been fully achieved. Furthermore, the surplus of unutilized biomass from the palm oil milling process has emerged as the key talking point leading to environmental concerns. As estimated, this palm oil biomass can generate approximately 5000 MW of electricity under 40% of operation efficiency. This significant power potential has the ability to replace Malaysia's yearly reliance on coal. Nonetheless, the limitations of technological stability, budgetary constraints, and other government policy concerns have prevented the potentials from being fulfilled. This necessitates an integrated framework that synergizes the decarbonization drive in order to realize the primary advantages of energy renewability and carbon neutrality. Among the suggested actions to decarbonize the power generating sector is an integrated scheme of palm oil production, biogas plant for electricity and steam generation, and biofuel pellet manufacture. This review provides an in‐depth overview of palm oil biomass for Malaysian power production decarbonization.This article is categorized under: Sustainable Energy > Bioenergy Climate and Environment > Net Zero Planning and Decarbonization Sustainable Development > Emerging Economies

The application of waste oils as pyrolysis feedstocks to produce high-grade biofuels is receiving extensive attention, which will diversify energy supplies and address environmental challenges caused by waste oils treatment and fossil fuel combustion. Waste oils are the optimal raw materials to produce biofuels due to their high hydrogen and volatile matter content. However, traditional disposal methods such as gasification, transesterification, hydrotreating, solvent extraction, and membrane technology are difficult to achieve satisfactory effects owing to shortcomings like enormous energy demand, long process time, high operational cost, and hazardous material pollution. The usage of clean and safe pyrolysis technology can break through the current predicament. The bio-oil produced by the conventional pyrolysis of waste oils has a high yield and HHV with great potential to replace fossil fuel, but contains a high acid value of about 120 mg KOH/g. Nevertheless, the application of CaO and NaOH can significantly decrease the acid value of bio-oil to close to zero. Additionally, the addition of coexisting bifunctional catalyst, SBA-15@MgO@Zn in particular, can simultaneously reduce the acid value and positively influence the yield and quality of bio-oil. Moreover, co-pyrolysis with plastic waste can effectively save energy and time, and improve bio-oil yield and quality. Consequently, this paper presents a critical and comprehensive review of the production of biofuels using conventional and advanced pyrolysis of waste oils.

Abstract This study presents the potential energy saving, life cycle cost analysis and payback period of the lighting system in campus buildings of the University of Malaya, Malaysia. The survey results indicate that almost 90% of the lighting system at the University Malaya campus consists of fluorescent lamp. Cost benefit analysis of retrofitting with more efficient lighting system in terms of potential energy saving, life cycle cost analysis and payback period have been conducted. Comparison of existing and retrofitting of lighting system based on the energy consumption is presented. From the analysis, it can be concluded that by using energy efficient lighting system will save a significant amounts of energy and cost, and also indirectly reducing emission.