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The present article addresses various novel and advanced approaches to mitigate frequency oscillation issues in an integrated power system. The suggested model of the multi-source power system is basically a two-area power system, where area2 is completely a microgrid system. The diesel generator, thermo-electric generator, wind generator, solar PV system, micro-turbine and fuel cell are the basic power generating sources in the microgrid system. The microgrid also has been associated with various energy saving equipments like battery and flywheel energy storage (FES) system to improve the power quality of the system. The unpredictable wind speed variant and fluctuation in solar power incorporates oscillations in voltage and frequency profile of the interconnected power system. In challenging to above issues, this research article has designed an innovative Fractional Order-type-2 fuzzy controller (FO-T2FC) to supress unwanted errors in the frequency and voltage of the system. Further, the proposed controller parameters are selected optimally with suggesting a novel Quassi- Oppositional Path Finder Algorithm (QO-PFA) under different operatings. An analysis on relative study is exercised to validate strength of the FO-T2FC control strategy and QO-PFA algorithm. Owing to the performance analysis, it is justified that proposed QO-PFA designed FO-T2FC controller is proved to be most potential candidate and able to improve the dynamic frequency response of area1 (Δf1) by 251.74% and 418.74% as compared to Type1 fuzzy controller and conventional PID controller respectively.

Graphical abstract Highlights • 2-D SnO 2 nanosheet/PVDF composite based flexible, self-cleaning nanogenerator. • Remarkable power density (4900 W/m3) and energy conversion efficiency (16.3%). • High output piezoelectric output (45 V) and superior current density (6.25 μA/cm2) • First Gr-IV oxide based inorganic-organic nanogenerator able to power 85 LEDs. • Capable to harvest human motion based and other low frequency mechanical energy. Abstract Flexible piezoelectric nanogenerators have been considered as the most promising candidates in recent years for powering the portable, bendable, and wearable electronics devices by scavenging low frequency biomechanical energy. This work reports an analysis of remarkable output power enhancement of a human-body motion based piezoelectric nanogenerator comprising of self-polarized 2D SnO 2 nanosheet/poly(vinylidene fluoride) (PVDF) nanocomposite. Structural, mechanical, thermal as well as piezoelectric properties of the composites were studied rigorously, which proved that 5 wt% SnO 2 nanosheet/PVDF composite is the most promising one for nanogenerator applications. The inorganic-organic 2D SnO 2 nanosheet/PVDF composite based piezoelectric nanogenerators (PSNG) were found to produce outstanding power output due to the gentle human finger imparting with a maximum voltage of 42 V and current density of 6.25 μA·cm−2. The output power density of the PSNG reached 4900 W·m−3 with an efficiency c.a. 16.3%. The obtained output of the reported nanogenerator is in well agreement with the fundamental piezoelectric theory. The improved performance of the self-polarized composite can be attributed to the incorporation of homogeneously distributed 2D SnO 2 nanosheets (2D SnO 2 NS) having high surface area, which enhances the electroactive β phase contain in PVDF composites as well as piezoelectric properties. The electrical energy (a.c.) generated from the nanogenerator due to gentle human finger imparting was directly utilized to illuminate 85 numbers commercial LEDs and to charge capacitors rapidly through a bridge rectifier. A hydrophobic 2D SnO 2 nanosheet/PVDF composite film (static contact angle of water drop ∼82.6°) was wrapped on the fabricated nanogenerator to attain self-cleaning feature of the PSNG, making the device water and dirt resistive. This work explores a new prospect for self-cleaning Gr-IV oxide/PVDF based high-efficiency, high power density energy harvester scavenging biomechanical energy for realizing next generation flexible self-powered electronics systems. [ABSTRACT FROM AUTHOR]

Philippine maritime industry is considered as a vital component in achieving inclusive growth and socio-economic progress. Philippines has been known as one of the susceptible to the impact of climate change countries, and generally the changing climate hampers its economic development. The government committed to reduce carbon emissions to 70% by 2030 during the 2015 Paris climate conference. This study aims to map the potential sites and vessels for electric ferry operation for transitioning to green maritime transportation in Philippines. At present there are 83 ports and 110 ferries in the country with 33670 registered vessels as of December 2017. It was identified that the 9201 vessels with 10≥GRT≥3 will be used for electrification as a kickoff in implementing electric ferry since these vessels are feasible for retrofitting the electric system. Implementing green energy sources in the country's marine transportation will reduce CO2 emission by 22.09% in the transport sector. [ABSTRACT FROM AUTHOR]

Microalgae are definitely on the way to become a sustainable, fast-growing natural green source for highly demanded market products. Research is currently looking at promising outstanding applications of microalgae among which are the production of biofuels from the fatty acids present in biomass, functional foods enriched with microalgae healthy bioactive molecules, and greenhouse gas mitigation (CO2consuming) based on high cell density microalgae cultures technology. Besides, other traditional microalgae applications are currently increasing in competitiveness in a growing market demand for green biomass, in which microalgae are widely recognized as a healthy, sustainable, and biological renewable resource. Among these traditional applications, microalgae are being used to improve the nutritional quality in animal feed, particularly in aquaculture, therapeutic agent source, and antioxidant activity. In addition, microalgae also show to be functional in waste effluents treatment to remove N and P, thus preventing eutrophication, heavy metals, and others contaminants. This review intends to offer a comprehensive overview of basic aspects of microalgae physiology, massive production of biomass, and current fields of applications at industrial scale. [ABSTRACT FROM PUBLISHER]

A high-efficiency boost dc-dc converter with adaptive peak-inductor-current (APIC) control method is proposed. Besides, a novel two-step startup procedure is also proposed and applied on the boost converter. The proposed integrated boost converter was fabricated by using a 0.18-μm 1P6M mixed-signal process with a die area of 0.96 mm × 0.75 mm, and it is meant to be used with low-power, low-voltage green energy sources and batteries, such as fuel cells, solar cells, and nickel-metal hydride batteries. Hence, the power efficiency, minimal startup voltage, and minimal input voltage are the most important design considerations. The output voltage of the proposed converter is set to 1.8V, and the measured power efficiency is up to 90.6%, occurring when the input voltage is 1.3 V, the output voltage is 1.8 V, and the load current is 50 mA. According to the measured results, the proposed converter can start up successfully with a 0.43-V input voltage. Then, the input voltage can be further lowered to 0.22 V after startup. Moreover, both the efficiency and the output voltage ripple are improved with the proposed APIC method. Furthermore, a two-step startup procedure, which does not require any extra startup assist circuit, is proposed. [ABSTRACT FROM AUTHOR]