A method for estimating the stack rating of vanadium redox flow batteries (VRFBs) through constant power characterization was developed. A stack of 22 cells, each with 1500 cm2 of nominal electrode area, was constructed and tested using constant current and constant power protocols. Typical ratios of charging to discharging power that prevail in various applications (e.g., peak shaving, wind power/solar photovoltaic power integration) were employed in the test protocols. The results showed that fractional energy storage capacity utilization and round-trip energy efficiency varied linearly with the power at which the energy was charged or discharged. A zero-dimensional electrochemical model was proposed based on the area-specific resistance to account for the energy stored/extracted during constant power discharge in the state of charge (SoC) window of 20% to 80%. It was shown that this could be used to rate a given stack in terms of charging and discharging power from the point of view of its application as a power unit. The proposed method enables stack rating based on a single polarization test and can be extended to flow battery systems in general. 

https://www.mdpi.com/2313-0105/8/8/85/pdf?version=1660057633

Model for Rating a Vanadium Redox Flow Battery Stack through Constant Power Charge–Discharge Characterization

Biomass energy is an essential and sustainable type of energy for today and the future because it is produced from renewable sources and is environmentally friendly compared to fossil-based energy. Biomass energy is the only renewable energy source that creates social and economic impact together. It creates added value, provides employment, and creates new tax opportunities in many fields from agriculture to industry, from the transportation sector to the banking insurance sector. While other renewable energy sources cannot be stored, the energy obtained from biomass can be stored. In this aspect, energy production from biomass stands out from other renewable energy sources. One of the crucial handicaps in evaluating biomass as an energy source is the collection of biomass. Biomass is produced in different amounts in different village centers, while country roads are suitable for trucks of different sizes. In this chapter, the multi-capacity vehicle routing problem is modeled for biomass collection in village centers at different production capacities. 

Decision-Making for Biomass Harvesting Routing by using the Simulated Annealing

There are numerous ways to assist blind people as they will not be able to detect text in all fonts, numbers, or low-light situations. To address this, an innovative model has been designed to detect various fonts, numbers, and so on. A camera has also been embedded to identify and capture text from printed text. Further, the image will be analyzed with Tesseract-Optical Character Recognition. Finally, to implement it in real-time, the Text-to-speech software is used.

A Peculiar Reading System for Blind People using OCR Technology

There is increasing urgency towards integration of renewable sources into electricity generation so as to minimize greenhouse gas (GHG) emissions. Renewable power sources are highly specific in prevalence, both regionally and temporally, and their utilization at utility scale for round-the-clock power supply poses the problem of matching power generation capacity and power demand at every instant of time. In the present work, we propose a model that integrates geographically distributed and diverse power sources with geographically spread-out power consumption centres and distributed and diverse electrical energy storage systems through transmission and storage loss models. For a regional electricity grid, the model computes, over a given day, the minute-by-minute power demand from and power generation in all districts, extracts matching power from a hierarchy of power sources so as to minimize transmission and storage losses, and stores/draws excess power in/from a variety of power storage options. For the specific case of the South Indian Power Grid (catering to about 285 million people in South India), the model shows that about 240 GWh of new electrical storage is required for round-the-clock power supply from non-GHG power sources.Graphical abstract 

/pdf/an-energy-mix-model-for-round-the-clock-power-supply-in-a-1k7uimqz.pdf

An energy-mix model for round-the-clock power supply in a decarbonized electricity generation scenario: case study of South India

Fluid engineering issues in the design of industrial-scale flow batteries

Full exploitation of solar photovoltaic electricity generation potential is being pegged back by land availability and the imbalance between demand and generation capacity. In the present work, a land-use-constrained generation model is proposed to identify natural pathways for energy flows within a politically administered region so as to evolve a sustainable nexus between electricity generation and consumption in a decentralized power generation scenario. The model envisages district-level coordination of electricity generation on barren rocky waste land and state-level coordination of distribution. Application of the model to five south Indian states, individually and together, demonstrates how the model is able to account for intra- and interstate disparities in electricity consumption and photovoltaic electricity generation potential. Two of these states can go completely renewable by using all available barren rocky area for electricity generation while the other three will have to rely on as yet untapped off-shore wind power and nuclear power to move towards carbon neutrality in power generation. When considered together, almost all the day time electrical energy demand of all the states can be met by utilizing barren rocky waste land for harnessing solar energy, thus saving considerably on storage losses.

A land-use-constrained, generation–transmission model for electricity generation through solar photovoltaic technology: a case study of south India

Today’s human contact is primarily through voice and text. A person must have a proper vision to view and access the information available in the form of text. In any case, individuals who are blind can gather information by using their hearing ability. The proposed method is a camera-based assistive message reading system that allows blind people and travellers to read the E-messages, printed notes, and other materials in their native languages. It integrates the ideas of optical character recognition (OCR), text to voice synthesizer (TTS), and interpreter in the Raspberry Pi. The proposed model coverts the text from verified records or a caption overlay available on an image into machine-readable text. Text-to-Speech conversion has been enabled by employing the OCR operation to sweep and read any language characters and numbers present in an image and interpret the information in any desired language, and lastly produce a voice output of the decoded text. Voice is the output obtained through the Raspberry Pi’s sound jack, which may be heard by using speakers or headphones. The main goal of this research work is to develop and implement a novel model to transcribe the Text to Speech in many dialects.

Translation of Multilingual Text into Speech for Visually Impaired Person

This paper presents four major approaches for diagnosing machine faults. Given the description of a system to be diagnosed and the observations on the system when it works, the need for diagnosis arises when the observations are different from those expected. The objective of diagnosis is to identify the malfunctioning components in a systematic and efficient way. The four approaches discussed are based on fault-tree, rule, model, and qualitative model. Early diagnosis systems used fault-tree and rule-based approaches. These are efficient in situations where an expert is able to provide the knowledge in the form of associations between symptoms and faults. Model-based and qualitative model-based approaches overcome many of the deficiencies of the earlier approaches. Model-based approaches can take care of situations (faults) not envisageda priori. Also, one can cater to minor variations in design using the same set of components and their interconnections. This paper discusses in each case, how the knowledge is represented and what diagnosis technique is to be adopted, and their relative advantages and disadvantages. Implementation of each method is also discussed.

/pdf/fault-diagnosis-of-machines-1gwpm8kbln.pdf

A T Arun Kumar

Papers

A land-use-constrained, generation–transmission model for electricity generation through solar photovoltaic technology: a case study of south India

Translation of Multilingual Text into Speech for Visually Impaired Person

Fault diagnosis of machines