The rising global warming concerns and explosive degradation of the environment requires the mainstream utilization of alternative fuels, such as hydroxy gas (HHO) which presents itself as a viable substitute for extracting the benefits of hydrogen. Therefore, an experimental study of the performance and emission characteristics of alternative fuels in contrast to conventional gasoline was undertaken. For experimentation, a spark ignition engine was run on a multitude of fuels comprising of gasoline, Liquefied petroleum gas (LPG) and hybrid blend of HHO with LPG. The engine was operated at 60% open throttle with engine speed ranging from 1600 rpm to 3400 rpm. Simultaneously, the corresponding performance parameters including brake specific fuel consumption, brake power and brake thermal efficiency were investigated. Emission levels of CO, CO₂, HC and NOx were quantified in the specified speed range. To check the suitability of the acquired experimental data, it was subjected to a Weibull distribution fit. Enhanced performance efficiency and reduced emissions were observed with the combustion of the hybrid mixture of LPG with HHO in comparison to LPG: on average, brake power increased by 7% while the brake specific fuel consumption reduced by 15%. On the other hand, emissions relative to LPG decreased by 21%, 9% and 21.8% in cases of CO, CO₂, and unburned hydrocarbons respectively. Incorporating alternative fuels would not only imply reduced dependency on conventional fuels but would also contribute to their sustainability for future generations. Simultaneously, the decrease in harmful environmental pollutants would help to mitigate and combat the threats of climate change.

Energy/fuel consumption and associated emissions are major concerns of transport sector. During the fiscal year (FY) of 2018, Pakistan’s transport sector consumed 22 million tons of oil equivalent (TOE) energy from burning of fossil fuels and emitted 52.8 million metric tons (MMT) of CO₂, which accounted for 30% of country’s overall carbon emissions. Different scenarios, such as business as usual (BAU), International Energy Agency Vision 2030 (IEA V30), International Energy Agency Vision 2050 (IEA V50), China Pakistan Economic Corridor (CPEC) and newly developed Pakistan National Electric Vehicle Policy (NEVP), are analyzed for Pakistan’s transport sector and results are forecasted for the next 17 years. The results show that effective electric vehicle (EV) adoption can cause significant reductions in energy/fuel consumption as well as atmospheric emissions. The distinctive outputs are important parameters in analyzing future energy demands, emissions and introducing effective sustainable energy policies for the transport sector of developing countries.

In the modern digital world, electronic devices are being widely employed for various applications where thermal performance represents a significant technical challenge due to continued miniaturization, high heat generated in the system, and non-uniform high-temperature causing failure. Phase change materials (PCMs) owing to the immense heat of fusion are primarily considered for thermal management, but their insulating properties hedge their applications in electronics cooling. Nano-enhanced phase change materials (NePCMs) have the ability to improve the thermal conductivity of PCM, decrease system temperature and escalate the operating time of devices. Accordingly, the current study focused on the experimental investigations for the thermal performance of three heat sinks (HS) with different configurations such as a simple heat sink (SHS), a square pin-fins heat sink (S_pfHS), and Cu foam integrated heat sink (Cu_fmHS) with various alumina nanoparticles mass concentrations (0.15, 0.20 and 0.25 wt%) incorporated in PCM (RT-54HC) and at heat flux (0.98–2.94 kW/m²). All HSs reduced the base temperature with the insertion of NePCM compared to the empty SHS. The experimental results identified that the thermal performance of Cu_fmHS was found to be superior in reducing base temperature and enhancing working time at two different setpoint temperatures (SPTs). The maximum drop in base temperature was 36.95%, and a 288% maximum working time enhancement was observed for Cu_fmHS. Therefore, NePCMs are highly recommended for the thermal management of the electronic cooling system.

Road transportation has received the attention of researchers due to its higher carbon footprint. Alternative fuels present major advantages in terms of environmental sustainability. For this reason, an enviro-economic analysis of alternative fuels carries great significance. However, scarce attempts have been rendered in order to ascertain the impact of a hydroxy gas (HHO) and compressed natural gas (CNG) mixture on sustainable environmental development. The current study addresses this issue by employing an HHO–CNG mixture and gasoline in spark ignition (SI) engines for the purposes of performance and environmental pollutants measurement. Then, engine emission data were substituted for Weibull distribution in order to establish suitability for 50 and 95% confidence intervals (CIs). The mixture outperformed gasoline in terms of brake-specific fuel consumption (BSFC) and emission contents. On average, hydroxy gas with CNG produced 10.59% lower oxides of nitrogen (NO_X) comparative to gasoline. Finally, the enviro-economic analysis also turned out to be in favor of the hydroxy gas mixture owing to a saving of 36.14% in USD/year due to 27.87% lower production of carbon dioxide (CO₂) emission.

Growing environmental concerns over global warming and depleting fossil fuel reserves are compelling researchers to investigate green fuels such as alcoholic fuels that not only show the concrete decrement in emissions but also enhance engine performance. The current study emphasizes the influence of different alcoholic fuel blends in gasoline on engine performance and emissions for an engine speed ranging from 1200 to 4400 rpm. The obtained performance results demonstrate that the brake power and brake thermal efficiency (BTE) increased with an incrementing blend percentage of ethanol and methanol in gasoline (EM). The minimum brake specific fuel consumption (BSFC) was ascertained using pure gasoline followed by E2 and then E5M5. The NO_x and CO₂ emissions can be described in the decreasing order of E, EM and gasoline due to same trend of exhaust gas temperature (EGT). CO results were in reverse order of CO₂. HC emissions were found in the increasing order of E, EM and pure gasoline. E10 performed better among all blends in terms of less exhaust emissions and engine performance. However, EM blended with gasoline significantly reduced NO_x. E5M5 produced 1.9% lower NO_x emission compared to E10 owing to 1.2% lower EGT. Moreover, greenhouse gases such as CO₂, which is mainly responsible for global warming reducing by 1.1% in case E5M5 as compared to E10.