LED illumination spectrum manipulation for increasing the yield of sweet basil (Ocimum basilicum l.)

© 2021 by the authors. Licensee MDPI, Basel, Switzerland. Manipulation of the LED illumination spectrum can enhance plant growth rate and development in grow tents. We report on the identification of the illumination spectrum required to significantly enhance the growth rate of sweet basil (Ocimum basilicum L.) plants in grow tent environments by controlling the LED wavebands illuminating the plants. Since the optimal illumination spectrum depends on the plant type, this work focuses on identifying the illumination spectrum that achieves significant basil biomass improvement compared to improvements reported in prior studies. To be able to optimize the illumination spectrum, several steps must be achieved, namely, understanding plant biology, conducting several trial‐and‐error experiments, iteratively refining experimental conditions, and undertaking accurate statistical analyses. In this study, basil plants are grown in three grow tents with three LED illumination treatments, namely, only white LED illumination (denoted W*), the combination of red (R) and blue (B) LED illumination (denoted BR*) (relative red (R) and blue (B) intensities are 84% and 16%, respectively) and a combination of red (R), blue (B) and far‐red (F) LED illumination (denoted BRF*) (relative red (R), blue (B) and far‐red (F) intensities are 79%, 11%, and 10%, respectively). The photosynthetic photon flux density (PPFD) was set at 155 μmol m−2 s−1 for all illumination treatments, and the photoperiod was 20 h per day. Experimental results show that a combination of blue (B), red (R), and far‐red (F) LED illumination leads to a one‐fold increase in the yield of a sweet basil plant in comparison with only white LED illumination (W*). On the other hand, the use of blue (B) and red (R) LED illumination results in a half‐fold increase in plant yield. Understanding the effects of LED illumination spectrum on the growth of plant sweet basil plants through basic horticulture research enables farmers to significantly improve their production yield, thus food security and profitability

Industrial IoT based condition monitoring for wind energy conversion system

Wind energy has been identified as the second dominating source in the world renewable energy generation after hydropower. Conversion and distribution of wind energy has brought technology revolution by developing the advanced wind energy conversion system (WECS) including multilevel inverters (MLIs). The conventional rectifier produces ripples in their output waveforms while the MLI suffers from voltage balancing issues across the DC-link capacitor. This paper proposes a simplified proportional integral (PI)-based space vector pulse width modulation (SVPWM) to minimize the output waveform ripples, resolve the voltage balancing issue and produce better-quality output waveforms. WECS experiences various types of faults particularly in the DC-link capacitor and switching devices of the power converter. These faults, if not detected and rectified at an early stage, may lead to catastrophic failures to the WECS and continuity of the power supply. This paper proposes a new algorithm embedded in the proposed PI-based SVPWM controller to identify the fault location in the power converter in real time. Since most wind power plants are located in remote areas or offshore, WECS condition monitoring needs to be developed over the internet of things (IoT) to ensure system reliability. In this paper, an industrial IoT algorithm with an associated hardware prototype is proposed to monitor the condition of WECS in the real-time environment. © 2015 CSEE

An intelligent controlling method for battery lifetime increment using state of charge estimation in PV-battery hybrid system

In a photovoltaic (PV)-battery integrated system, the battery undergoes frequent charging and discharging cycles that reduces its operational life and affects its performance considerably. As such, an intelligent power control approach for a PV-battery standalone system is proposed in this paper to improve the reliability of the battery along its operational life. The proposed control strategy works in two regulatory modes: maximum power point tracking (MPPT) mode and battery management system (BMS) mode. The novel controller tracks and harvests the maximum available power from the solar cells under different atmospheric conditions via MPPT scheme. On the other hand, the state of charge (SOC) estimation technique is developed using backpropagation neural network (BPNN) algorithm under BMS mode to manage the operation of the battery storage during charging, discharging, and islanding approaches to prolong the battery lifetime. A case study is demonstrated to confirm the effectiveness of the proposed scheme which shows only 0.082% error for real-world applications. The study discloses that the projected BMS control strategy satisfies the battery-lifetime objective for off-grid PV-battery hybrid systems by avoiding the over-charging and deep-discharging disturbances significantly

An Intelligent Controlling Method for Battery Lifetime Increment Using State of Charge Estimation in PV-Battery Hybrid System

In a photovoltaic (PV)-battery integrated system, the battery undergoes frequent charging and discharging cycles that reduces its operational life and affects its performance considerably. As such, an intelligent power control approach for a PV-battery standalone system is proposed in this paper to improve the reliability of the battery along its operational life. The proposed control strategy works in two regulatory modes: maximum power point tracking (MPPT) mode and battery management system (BMS) mode. The novel controller tracks and harvests the maximum available power from the solar cells under different atmospheric conditions via MPPT scheme. On the other hand, the state of charge (SOC) estimation technique is developed using backpropagation neural network (BPNN) algorithm under BMS mode to manage the operation of the battery storage during charging, discharging, and islanding approaches to prolong the battery lifetime. A case study is demonstrated to confirm the effectiveness of the proposed scheme which shows only 0.082% error for real-world applications. The study discloses that the projected BMS control strategy satisfies the battery-lifetime objective for off-grid PV-battery hybrid systems by avoiding the over-charging and deep-discharging disturbances significantl

Monitoring of renewable energy systems by IoT‐aided SCADA system

With the rapid increase of renewable energy generation worldwide, real‐time information has become essential to manage such assets, especially for systems installed offshore and in remote areas. To date, there is no cost‐effective condition monitoring technique that can assess the state of renewable energy sources in real‐time and provide suitable asset management decisions to optimize the utilization of such valuable assets and avoid any full or partial blackout due to unexpected faults. Based on the Internet of Things scheme, this paper represents a new application for the Supervisory Control and Data Acquisition (SCADA) system to monitor a hybrid system comprising photovoltaic, wind, and battery energy storage systems. Electrical parameters such as voltage, current, and power are monitored in real‐time via the ThingSpeak website. Network operators can control components of the hybrid power system remotely by the proposed SCADA system. The SCADA system is interfaced with the Matlab/Simulink software tool through KEPServerEX client. For cost‐effective design, low‐cost electronic components and Arduino Integrated Development Environment ATMega2560 remote terminal unit are employed to develop a hardware prototype for experimental analysis. Simulation and experimental results attest to the feasibility of the proposed system. Compared with other existing techniques, the developed system features advantages in terms of reliability and cost‐effectivenes

Compound Semiconductor Epitaxial Growth Techniques

The aim of this paper is to review the different growth techniques used for compound semiconductor epitaxial layer growth, including LPE, HVPE, MOVPE, MOCVD, MBE & their reasonable comparison. As the compound semiconductor have elegant characteristics, so recently different semiconductor and its alloys becoming great importance in many applications due to its variable band gap properties. We can change its properties by changing temperature, doping & carrier concentration, & most importantly the performance of semiconductor devices strongly dependent on precious control of growth techniques. So, the choice of efficient growth techniques by accumulating with the proper doping we can get high quality semiconductor device, as well high power and high temperature electronics devices

Design, development, and performance evaluation of an energy-efficient spectrally selective photovoltaic mini greenhouse

Due to decreasing land availability for agricultural use, most countries are endeavoring to find more sustainable and energy-efficient agricultural practices. Thus, achieving both United Nations Sustainable Development Goals (SDGs)- SDG-2 (i.e., zero hunger) and SDG-7 (i.e., affordable and clean energy) require advances in contemporary greenhouse farming. This project aims to develop novel approaches to resolve this problem by first determining the wavelength ranges that plants require for optimum plant growth and designing a NANO- coating filter from this wavelength range that transmits only the necessary wavelength for the plant. An additional aim is to harness the solar spectral components to generate electricity using Photovoltaic (PV) technology, which enables Light Emitting Didoe (LED) light sources to be used, thus providing a more extended photoperiod. Various types of PV-based greenhouses are exploited for sustainable agriculture. However, these PV greenhouses yield diverse performances with varying uncertainties, depending on the type of solar panel used (Opaque, Semi-Transparent, Organic), its installation location (tropical, dry, and polar), the percentage of PV roof cover (ratio of PV and unshaded area), and transparency levels (light transmissivity). This imposes the risk of obtaining a higher energy yield and optimum plant biomass from the greenhouse. The selection of suitable solar panels has the direct cost-benefit of preventing land misutilization and optimizing crop growth while reducing the environmental impact. In some cases, it is also possible that the cost of integrating and replacing a solar panel could exceed the cost of the greenhouse itself. Therefore, the challenges in conjugating a portable solar power system with mini greenhouses are explored in the research, along with a summary of the emerging farming technologies. Finally, an innovative mini-greenhouse has been developed using NANO-sheet coverings and flexible mono-crystalline PV technologies to realize a progressive, self-sustainable, and protected cropping system. It supports the claims that technical maturity, higher efficiency, and easy installation of conventional flexible silicon PV panels make them a strong choice for a portable solar power system. Therefore, a novel strategy that provides an optimum growth strategy for greenhouse-grown plants while supplying sustainable energy for supplementary lighting systems is proposed in this thesis. By integrating renewable energy sources, optimum growth strategy, and advanced lighting systems, greenhouse operators can improve the efficiency, productivity, and profitability of their operations while also reducing their environmental impact

Observation of fuel cell technology and upgraded photovoltaic system for rural telecom system in Bangladesh

Free to read on publisher website The objective of this paper is to explore feasibility of green power generation for telecommunication system in Bangladesh. The possibility of solar, fuel cell as primary and backup power source for base transceiver station (BTS) at telecom sites, local data transmission system etc. situated in remote area as well as in islands off the national grid or having poor electricity supply is deeply analyzed here. Power assurance to BTS even in massive black out is the real headache of today’s global world. Among various types of fuel cell proton exchange membrane fuel cell (PEMFC) and an upgraded photovoltaic system (solar) have introduced here. Enhancing the PEMFC efficiency to 57.26% and lifetime of PEMFC is also conceptualized in this paper. Not only power assurance but also environmentally friendly technology has also given deep concern

LED Illumination Spectrum Manipulation for Increasing the Yield of Sweet Basil (Ocimum basilicum L.)

Manipulation of the LED illumination spectrum can enhance plant growth rate and development in grow tents. We report on the identification of the illumination spectrum required to significantly enhance the growth rate of sweet basil (Ocimum basilicum L.) plants in grow tent environments by controlling the LED wavebands illuminating the plants. Since the optimal illumination spectrum depends on the plant type, this work focuses on identifying the illumination spectrum that achieves significant basil biomass improvement compared to improvements reported in prior studies. To be able to optimize the illumination spectrum, several steps must be achieved, namely, understanding plant biology, conducting several trial-and-error experiments, iteratively refining experimental conditions, and undertaking accurate statistical analyses. In this study, basil plants are grown in three grow tents with three LED illumination treatments, namely, only white LED illumination (denoted W*), the combination of red (R) and blue (B) LED illumination (denoted BR*) (relative red (R) and blue (B) intensities are 84% and 16%, respectively) and a combination of red (R), blue (B) and far-red (F) LED illumination (denoted BRF*) (relative red (R), blue (B) and far-red (F) intensities are 79%, 11%, and 10%, respectively). The photosynthetic photon flux density (PPFD) was set at 155 µmol m−2 s−1 for all illumination treatments, and the photoperiod was 20 h per day. Experimental results show that a combination of blue (B), red (R), and far-red (F) LED illumination leads to a one-fold increase in the yield of a sweet basil plant in comparison with only white LED illumination (W*). On the other hand, the use of blue (B) and red (R) LED illumination results in a half-fold increase in plant yield. Understanding the effects of LED illumination spectrum on the growth of plant sweet basil plants through basic horticulture research enables farmers to significantly improve their production yield, thus food security and profitability