Muhammad Amin

Energy consumption in the building sector, particularly for air conditioning (AC), accounts for approximately 30% of global energy use and one-third of greenhouse gas emissions. In urban areas, the use of conventional materials such as red bricks and concrete blocks contributes to increased indoor temperatures, thereby raising electricity demand. One promising solution is thermal energy storage technology using Phase Change Materials (PCM). This study presents an experimental investigation of heat absorption in 30×30×15 cm concrete specimens with the addition of paraffin and beeswax PCM encapsulated in plastic balls. The PCM content was varied at 0%, 5%, 10%, and 15% of the concrete volume. Heating was applied using three 160-watt incandescent lamps. The results showed that concrete containing PCM absorbed more heat than the control specimens. Heat absorption by paraffin was 8.19%, 9.83%, and 16.39%, while beeswax achieved 4.91%, 8.19%, and 14.75%. These findings suggest that the use of PCM encapsulated in plastic balls can enhance the thermal energy efficiency of concrete and reduce electricity consumption in buildings.

The increasing need for cleaner and more efficient fuels encourages the use of bio-additives to improve the combustion quality of gasoline engines. However, research on the direct effect of variations in the ratio of clove oil in Pertalite gasoline on engine performance and emissions is still limited. This study examined the effect of mixing clove oil in four fuel compositions, namely pure Pertalite (P0), Pertalite + clove oil 0.5% (P0.5), 1% (P1), and 2% (P2), on engine performance parameters and exhaust emission characteristics. The results showed that the P2 blend provided the most significant improvement in engine performance, characterized by a 4.6% increase in torque and 6.3% power, a decrease in specific fuel consumption of up to 7.1%, and an increase in calorific value of up to 7.8%. Thermal efficiency also increased at high rounds of 1 %, indicating better energy conversion. In terms of emissions, a decrease in CO of 0.006% and a decrease in CO₂ of 0.1% indicate more complete combustion, although HC increases by 34 ppm (parts per million) due to the volatile characteristics of clove oil. Overall, the addition of 2% clove oil has been shown to improve combustion quality without engine modification. These findings confirm the potential of clove oil as a viable and relevant renewable bio-additive to support energy transition efforts towards a cleaner and more sustainable transportation system.

This study investigates the effect of Phase Change Material (PCM) on temperature, efficiency, and productivity. The prototype solar distillation system is tube-shaped, with a length of 50 cm and a diameter of 4 inches, using a parabolic trough collector. The PCM used is beeswax, which is wrapped in aluminum foil. The results show that the use of PCM improves freshwater productivity. On the first day, the PCM method showed an 11% increase in production, and on the second day, freshwater production increased by 13%. The production rate with PCM was 0.76 L/m²/day, compared to the conventional method, which had a rate of 0.67 L/m²/day. The system with PCM also achieved high efficiency, reaching 11,47% on the first day and 13,9% on the second day. The system remained stable in the afternoon and evening, maintaining temperatures above 35 °C at night, compared to the system without PCM, where the temperature dropped to 30 °C. The use of PCM significantly enhanced the overall performance of the distillation system.

Solar distillation is a desalination method that utilizes solar energy to convert saline water into freshwater. However, the efficiency of this process is often limited by temperature fluctuations and low heat storage capacity. Phase Change Material (PCM) has been used as a thermal storage medium in solar distillation systems, but the low thermal conductivity of pure PCM remains a major challenge. To address this limitation, this study incorporates graphene carbon nanoparticles into beeswax-based PCM to enhance its thermal properties. This research examines the effect of adding 0.3% graphene to beeswax PCM on the performance of a tubular solar distillation system equipped with a Parabolic Trough Collector (PTC). The experiment compares the performance of pure PCM and nano-PCM, each weighing 90 grams and enclosed in an aluminum foil bag. The experimental results indicate that the addition of graphene to beeswax PCM improves solar distillation performance based on three key parameters, namely temperature, productivity, and efficiency. Nano-PCM achieved a maximum temperature of 76 °C, representing a 2.7% increase compared to pure PCM. In terms of productivity, the distilled water yield of nano-PCM was recorded at 0.834 L/m² on October 15, 2024, and 0.819 L/m² on October 17, 2024, marking an increase of 3.22% and 6.64%, respectively, compared to pure PCM. Furthermore, the system’s efficiency also improved with an increase of 3.03% on October 15, 2024, and 6.7% on October 17, 2024. Overall, this study demonstrates that the use of nano-PCM enhances the performance of solar distillation, particularly in terms of operating temperature, water productivity, and system efficiency. These findings highlight the significant potential of nano-PCM applications in large-scale solar distillation systems to improve freshwater production efficiency.

Cooking, a fundamental human necessity, frequently relies on environmentally harmful energy sources. Concentrated solar power offers a promising solution through solar cookers to address this issue. This study assesses a Parabolic Trough Collector (PTC) solar cooker's performance with two reflector materials: chrome stickers and glass mirrors. The PTC-type solar cooker comprises essential components, including an absorber tube, a flexible conduit, and a spiral-shaped cooking container holder that accommodates a diverse range of cooking vessels. In the configuration of the PTC collector, reflectors fabricated from chrome stickers and glass mirrors are strategically employed to harness and concentrate solar radiation effectively. The absorber tube, crafted from copper, is filled with a heat-transfer fluid consisting of soya oil. Experimental investigations were conducted in a two-stage process, encompassing trials without any applied load and subsequently with varying loads. In the no-load experiments, alterations were made to the PTC collector's inclination angle, spanning the ranges of 15º, 20º, 25º, and 30º. In contrast, the load-bearing tests encompassed the assessment of the PTC solar cooker's performance under a diverse array of cooking scenarios, including boiling water, heating oil, frying eggs, and crisping crackers. The evaluated parameters encompassed key metrics such as incident solar radiation (I_r), ambient temperature (T_a), receiver temperature (T_r), fluid temperature (T_f), spiral furnace temperature (T_sf), and load temperature (T_o). Subsequently, the outcomes of the experiments were employed to determine the efficiency of the solar cooker. Analysis of the no-load test results indicates that the most favorable performance, as observed in the parameters T_r, T_f, and T_sf, is achieved at a collector inclination angle of 15º for both chrome sticker and glass mirror reflector materials. The solar cooker demonstrated commendable proficiency in boiling water, heating oil, frying eggs, and crisping crackers, accomplishing these tasks within a time frame ranging from 5 to 20 minutes. Notably, the solar cooker featuring the glass mirror reflector exhibited a superior thermal efficiency of 33.7%, surpassing the efficiency of the counterpart with the chrome sticker reflector, which registered an efficiency of 30.9%. These findings underscore the efficacy of the glass mirror reflector in harnessing solar energy for enhanced cooking performance within this solar cooker configuration.

One way to overcome the scarcity of clean water through sustainable approach is by utilizing a solar distillation system. This easy-to-use technology is adopting tubular solar distillation. The three main components, which are the most essential for producing the amount of permeate, are the solar collector, tubular and heat exchanger (HE). This study aims to determine the performance of a tubular solar distillation device equipped with HE using a parabolic trough collector (PTC). The PTC has an area of 5.1 m² covered with a solar reflective chrome film. Aluminum tubular acts as the feedwater heater. The HE is placed inside the tubular, which acts as a coolant to convert the steam phase into freshwater/permeate and as a feedwater heater to flow into the tubular. In the present study, several parameters were tested: comprise temperature, solar radiation, pressure, humidity, mass flow rate, permeate productivity and efficiency. This study demonstrated the production of a sufficient amount of permeate, which was 5.32 L for 6 h. The efficiency of this device yielded a peak of 48.2% during solar radiation of 813 W/m² in an average ambient temperature of 32 °C, with an overall average of 44.59%.

Indonesia has been blessed with excellent solar heat distribution, which can be used as renewable energy to heat water. Various technologies have been developed to utilize these inexhaustible thermodynamic resources, in the form of photons arrays, converted into concentrated heat for daily use, i.e., solar water heater. This renewable-based water heating system can provide significant energy efficiency, benefit the environment, and reduce energy use costs. This experimental study attempts to harvest the energy from the sun using a cylindrical through collector (CTC) type solar concentrator. The CTC was made of the solar reflective film (SRF) affixed to concentrator collector surfaces which was then mounted on an adjustable angle frame of the concentrator collector support. The heat generated from the concentrator was stored in water, and phase change material is embedded in the system to retain the heat longer. The research was carried out in Langsa City, Aceh, Indonesia. The results showed that water heaters using CTC systems could produce 16 L of hot water retained at 40–60 °C for four hours. With the addition of beeswax, the water temperature of the same capacity can be maintained at 40–60 °C for around 5 h. This technology demonstrated an excellent result that produces as much as 60 L of water per day, increasing solar thermal energy efficiency. This technology presented a great potential for replication or even for further development on an industrial scale.

| Amongst all the floricultural crop, Rose is one of the most important crop both economically as well as aesthetically whose beauty must be enjoyed for longer period of life. Current experiment was performed to discover the comparative consequence of various vase solutions to improve the post-harvest qualities and extend vase life of Rosa hybrida cv. Freedom. The research was performed at the research area of Department of Horticultural Sciences, The Islamia University of Bahawalpur. There were 11 treatments comprising of honey (T 1 ), sugar (T 2 ), salicylic acid (T 3 ), acetic acid (T 4 ), indole acetic acid (IAA) (T 5 ) and combination of all solutions with sugar. These treatments were compared with tap water (T 0 ). There were four plants in each treatment with three replications which were arranged according to completely randomized design (CRD) under room temperature. The results showed that maximum fresh weight (g) was obtained in T 4 (acetic acid), flower head diameter (mm) and flower color was ideal under T 3 (salicylic acid). Maximum dry weight (g), highest flower freshness on 1 st and 3 rd day, minimum petal discoloration which leads to productive market acceptability and highest vase life was recorded in T 2 (sugar). It is worth to note that lowest market acceptability of flower was observed when sugar is combined with other solution especially IAA. It means sugar reduces its effectiveness when combined with growth regulators. From this experiment, it can be concluded that sugar (T 2 ) provide ideal medium for enhancing the post-harvest attributes of Rosa hybrida cv. Freedom.