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Full-Text Articles in Engineering

Renewing The Paradigm: Simulating The Miso Region Electrical Grid Using Renewable Energy Generation With Implementation Of Long-Term Hydrogen Storage, Jackson C. Henningfield May 2021

Renewing The Paradigm: Simulating The Miso Region Electrical Grid Using Renewable Energy Generation With Implementation Of Long-Term Hydrogen Storage, Jackson C. Henningfield

Macalester Journal of Physics and Astronomy

The current electrical grid regime is not optimized to include renewable sources of power generation such as wind and solar. Electrical storage, as of now, is primarily established through the short-term generation and demand-meeting consumption leaving much of the grid susceptible to inefficiencies and power loss during natural events that leave grids out of commission. Delineating a new type of long-term storage, a hydrogen fuel cell, would ensure a reliable source of power to the masses regardless of the physical and climatic geography. The MISO region provides a perfect case study to introduce the ideas of diverse energy generation and ...


Potential Energy Generation From Agricultural Residue In Indonesia, Adrian Rizqi Irhamna Aug 2020

Potential Energy Generation From Agricultural Residue In Indonesia, Adrian Rizqi Irhamna

English Language Institute

Indonesia has great potential of biomass sources from their agricultural residue, which can potentially be used for alternative energy generation. This preliminary research explores the most suitable technology for energy generation from agricultural residue and its challenge for application in Indonesia. The study showed that biomass utilization via the direct combustion process is recommended for energy generation. It is also reported that the pretreatment process of drying and washing, are required to increase the fuel quality and plant efficiency.


Applying Renewable Energies Against Climate Change: Solar Photovoltaic (Pv) Energy, Juan Jose Estribi Aug 2020

Applying Renewable Energies Against Climate Change: Solar Photovoltaic (Pv) Energy, Juan Jose Estribi

English Language Institute

In recent years, more efforts towards fighting climate change have been done. As a direct response, research and technology have offered several insights regarding the specific causes, effects, and even possible solutions for resolving this global issue. Among these solutions, renewable energies and their potential contributions as clean energy sources can be assessed as feasible options for the energy transformation through the decarbonization process of the energy industry. This poster is mainly focused on solar photovoltaic (PV) energy and its great potential as a renewable energy by making a brief assessment of some important aspects such as resource availability, its ...


Waste To Energy: Solid Fuel Production From Biogas Plant Digestate And Sewage Sludge By Torrefaction-Process Kinetics, Fuel Properties, And Energy Balance, Kacper Świechowski, Martyna Hnat, Paweł Stępień, Sylwia Stegenta-Dąbrowska, Szymon Kugler, Jacek A. Koziel, Andrzej Białowiec Jun 2020

Waste To Energy: Solid Fuel Production From Biogas Plant Digestate And Sewage Sludge By Torrefaction-Process Kinetics, Fuel Properties, And Energy Balance, Kacper Świechowski, Martyna Hnat, Paweł Stępień, Sylwia Stegenta-Dąbrowska, Szymon Kugler, Jacek A. Koziel, Andrzej Białowiec

Agricultural and Biosystems Engineering Publications

Sustainable solutions are needed to manage increased energy demand and waste generation. Renewable energy production from abundant sewage sludge (SS) and digestate (D) from biogas is feasible. Concerns about feedstock contamination (heavy metals, pharmaceuticals, antibiotics, and antibiotic-resistant bacteria) in SS and D limits the use (e.g., agricultural) of these carbon-rich resources. Low temperature thermal conversion that results in carbonized solid fuel (CSF) has been proposed as sustainable waste utilization. The aim of the research was to investigate the feasibility of CSF production from SS and D via torrefaction. The CSF was produced at 200~300 °C (interval of 20 ...


An Assessment Of Renewable Energy Technology Implementation In Storrs, Connecticut: Emissions Reduction And Feasibility Of A Microgrid System At Uconn, Sophie Macdonald May 2020

An Assessment Of Renewable Energy Technology Implementation In Storrs, Connecticut: Emissions Reduction And Feasibility Of A Microgrid System At Uconn, Sophie Macdonald

Honors Scholar Theses

The purpose of this project is to design a clean energy-sourced microgrid for UConn’s main campus that would reduce the university’s energy emissions while remaining within the geographic boundaries of viable UConn-owned land. Economic cost was not considered in this analysis; instead, emissions and space constraints were the optimized measures of value and feasibility. Sources of energy that were considered include photovoltaics (PV), wind turbines, hydrokinetic systems, and fuel cells. Energy storage capacity was included in the analysis as well. The overall system was optimized first by ignoring space constraints and for a minimum of 10% reduction from ...


Cybersecurity Methods For Grid-Connected Power Electronics, Stephen Joe Moquin May 2020

Cybersecurity Methods For Grid-Connected Power Electronics, Stephen Joe Moquin

Theses and Dissertations

The present work shows a secure-by-design process, defense-in-depth method, and security techniques for a secure distributed energy resource. The distributed energy resource is a cybersecure, solar inverter and battery energy storage system prototype, collectively called the Cybersecure Power Router. Consideration is given to the use of the Smart Green Power Node for a foundation of the present work. Metrics for controller security are investigated to evaluate firmware security techniques. The prototype's ability to mitigate, respond to, and recover from firmware integrity degradation is examined. The prototype shows many working security techniques within the context of a grid-connected, distributed energy ...


Studies Of Initial Growth Of Gan On Inn, Alaa Alnami Dec 2019

Studies Of Initial Growth Of Gan On Inn, Alaa Alnami

Theses and Dissertations

III-nitride materials have recently attracted much attention for applications in both the microelectronics and optoelectronics. For optoelectronic devices, III-nitride materials with tunable energy band gaps can be used as the active region of devices to enhance the absorption or emission. A such material is indium nitride (InN), which along with gallium nitride (GaN) and aluminum nitride (AlN) embody the very real promise of forming the basis of a broad spectrum, a high efficiency solar cell. One of the remaining complications in incorporating InN into a solar cell design is the effects of the high temperature growth of the GaN crystal ...


Oxytree Pruned Biomass Torrefaction: Process Kinetics, Kacper Świechowski, Sylwia Stegenta-Dąbrowska, Marek Liszewski, Przemysław Bąbelewski, Jacek A. Koziel, Andrzej Białowiec Oct 2019

Oxytree Pruned Biomass Torrefaction: Process Kinetics, Kacper Świechowski, Sylwia Stegenta-Dąbrowska, Marek Liszewski, Przemysław Bąbelewski, Jacek A. Koziel, Andrzej Białowiec

Agricultural and Biosystems Engineering Publications

Oxytree is a fast-growing energy crop with C4 photosynthesis. In this research, for the first time, the torrefaction kinetic parameters of pruned Oxytree biomass (Paulownia clon in Vitro 112) were determined. The influence of the Oxytree cultivation method and soil class on the kinetic parameters of the torrefaction was also investigated. Oxytree pruned biomass from a first-year plantation was subjected to torrefaction within temperature range from 200 to 300 °C and under anaerobic conditions in the laboratory-scale batch reactor. The mass loss was measured continuously during the process. The relative mass loss increased from 1.22% to 19.56% with ...


Our Energy Future, Fall/Winter 2007, Issue 15 Sep 2019

Our Energy Future, Fall/Winter 2007, Issue 15

Sustain Magazine

No abstract provided.


Renewable Energy, Fall/Winter 2011, Issue 23 Sep 2019

Renewable Energy, Fall/Winter 2011, Issue 23

Sustain Magazine

No abstract provided.


Proof-Of-The-Concept Of Spent Mushrooms Compost Torrefaction - Preliminary Studies Of Process Kinetics And The Influence Of Temperature And Duration On Calorific Value Of The Biochar, Ewa Syguła, Jacek A. Koziel, Andrzej Białowiec Jul 2019

Proof-Of-The-Concept Of Spent Mushrooms Compost Torrefaction - Preliminary Studies Of Process Kinetics And The Influence Of Temperature And Duration On Calorific Value Of The Biochar, Ewa Syguła, Jacek A. Koziel, Andrzej Białowiec

Agricultural and Biosystems Engineering Publications

Poland is the 3rd producer of mushrooms in the world. Mushroom production in Poland accounts for nearly 25% of the total production in the EU, and it is still growing. One type of waste generated during mushroom production is mushroom spent compost (MSC), with a 5:1 (MSC: mushrooms) production rate. We investigated valorizing the MSC to produce fuel via torrefaction (‘roasting’, a.k.a. low-temperature pyrolysis). Specifically, we developed models for the MSC torrefaction kinetics using thermogravimetric analyses (TGA) and the effects of torrefaction temperature (200~300 °C) and process duration time (20~60 min) on the resulting biochar ...


Waste To Carbon: Preliminary Research On Mushroom Spent Compost Torrefaction, Ewa Syguła, Jacek A. Koziel, Andrzej Białowiec Jun 2019

Waste To Carbon: Preliminary Research On Mushroom Spent Compost Torrefaction, Ewa Syguła, Jacek A. Koziel, Andrzej Białowiec

Agricultural and Biosystems Engineering Publications

Mushroom production in Poland is an important and dynamically developing element of diverse agriculture. Mushroom spent compost (MSC) is major waste generated during production, i.e., MSC: mushrooms is ~5:1. To date, the main use of MSC is soil application as organic fertilizer. To date, several methods of MSC treatment have been researched and developed including production of compost, bioethanol, biogas, enzyme lactase, xylo-saccharides, and hydrogen. Torrefaction may be considered a novel approach for biomass valorization. Thus, we are pioneering the potential use of MSC valorization via torrefaction. We explored valorizing the waste biomass of MSC via thermal treatment ...


Fuel Properties Of Torrefied Biomass From Pruning Of Oxytree, Kacper Świechowski, Marek Liszewski, Przemysław Bąbelewski, Jacek A. Koziel, Andrzej Białowiec Apr 2019

Fuel Properties Of Torrefied Biomass From Pruning Of Oxytree, Kacper Świechowski, Marek Liszewski, Przemysław Bąbelewski, Jacek A. Koziel, Andrzej Białowiec

Agricultural and Biosystems Engineering Publications

The very fast growing Oxytree (PaulowniaClonin Vitro 112) is marketed as a promising new energy crop. The tree has characteristically large leaves, thrives in warmer climates, and requires initial pruning for enhanced biomass production in later years. We explored valorizing the waste biomass of initial (first year) pruning via thermal treatment. Specifically, we used torrefaction (‘roasting’) to produce biochar with improved fuel properties. Here for the first time, we examined and summarized the fuel properties data of raw biomass of Oxytree pruning and biochars generated via torrefaction. The effects of torrefaction temperature (200~300 °C), process time (20~60 min ...


An Agent-Based Approach To Modeling Sustainable Sociotechnical Systems, Anuj Mittal Jan 2019

An Agent-Based Approach To Modeling Sustainable Sociotechnical Systems, Anuj Mittal

Graduate Theses and Dissertations

A gradual evolution in the food and energy sectors towards decentralized decision-making is requiring participant organizations to consider new approaches to the design of policies and processes. Increasing consumer preference for food sourced from small-scale regional farmers has led to changing logistics requirements. Similarly, as consumers have become conscious of the impacts of climate change on the environment, they have begun to adopt renewable sources to meet their energy needs. Moreover, the emergence of new technologies has enabled consumers to generate their own energy. Such shifts in decision-making power to consumers necessitates the consideration of their perspectives and preferences when ...


The Effectiveness Of The Use Of Solar Panels In Hotels Of Durres Area, Asllan Hajderi, Shkelqim Gjevori Nov 2018

The Effectiveness Of The Use Of Solar Panels In Hotels Of Durres Area, Asllan Hajderi, Shkelqim Gjevori

International Journal of Business and Technology

In the present study is analyzing the case of the application of solar energy with vacuum tube collectors for heating water for sanitary needs in hotels of Durres areas. In recent years there has been a special interest by the leading authorities to the EU countries and the U.S., for the use of renewable energies in general and solar energy in particular. This is mainly related with the reduction of environmental pollution from gas CO2, which directly influences the greenhouse effect and global warming.

Unlike other forms of renewable energy, like wind turbines, photovoltaic panels and biomass usages, the ...


Lithium And The Foreseeable Future, Paolo Vargas May 2018

Lithium And The Foreseeable Future, Paolo Vargas

Mechanical Engineering Undergraduate Honors Theses

This paper aims to clarify the uncertainties regarding worldwide lithium resource availability in the years to come. Previous studies made on the subject are presented with some ambiguity and this work intends to fill the gaps. The information and data presented throughout this script with respect to global lithium resources and reserves are mostly based on data released by the United States Geological Survey (USGS). Lithium resource availability in the future is a point of paramount significance primarily for the automotive, portable electronics, and the power generation industry. Since, a change of supply would ultimately affect the price of lithium ...


Supported Perovskite-Type Oxides: Establishing A Foundation For Co2 Conversion Through Reverse Water-Gas Shift Chemical Looping, Bryan J. Hare Mar 2018

Supported Perovskite-Type Oxides: Establishing A Foundation For Co2 Conversion Through Reverse Water-Gas Shift Chemical Looping, Bryan J. Hare

Graduate Theses and Dissertations

Perovskite-type oxides show irrefutable potential for feasible thermochemical solar-driven CO2 conversion. These materials exhibit the exact characteristics required by the low temperature reverse water-gas shift chemical looping process. These properties include structural endurance and high oxygen redox capacity, which results in the formation of numerous oxygen vacancies, or active sites for CO2 conversion. A major drawback is the decrease in oxygen self-diffusion with increasing perovskite particle size. In this study, the La0.75Sr0.25FeO3 (LSF) perovskite oxide was combined with various supports including popular redox materials CeO2 and ZrO2 along with ...


Communication Based Control For Dc Microgrids, Mahmoud S. Saleh, Yusef Esa, Ahmed Mohamed Jan 2018

Communication Based Control For Dc Microgrids, Mahmoud S. Saleh, Yusef Esa, Ahmed Mohamed

Publications and Research

Centralized communication-based control is one of the main methods that can be implemented to achieve autonomous advanced energy management capabilities in DC microgrids. However, its major limitation is the fact that communication bandwidth and computation resources are limited in practical applications. This can be often improved by avoiding redundant communications and complex computations. In this paper, an autonomous communication-based hybrid state/event driven control scheme is proposed. This control scheme is hierarchical and heuristic, such that on the primary control level, it encompasses state-driven local controllers, and on the secondary control level, an event-driven MG centralized controller (MGCC) is used ...


Consumer Engagement With Efficient And Renewable Energy Technology: Case Studies On Smart Meter Utilization And Support For A Community Anaerobic Biodigester System In Vermont, Samantha Whitney Lewandowski Jan 2018

Consumer Engagement With Efficient And Renewable Energy Technology: Case Studies On Smart Meter Utilization And Support For A Community Anaerobic Biodigester System In Vermont, Samantha Whitney Lewandowski

Graduate College Dissertations and Theses

Residential electricity consumption in the United States has many adverse impacts, such as greenhouse gas emissions, dependence on fossil fuels, and costs. Efficient and renewable energy technologies have the potential to help mitigate some of these impacts, but appear to be under-utilized in the United States. One major barrier to expanding the deployment of these kinds of technologies and maximizing the benefits they can provide is a lack of consumer engagement. The overall purpose of this thesis is to better understand the extent to which efficient and renewable energy technologies are being engaged with and what factors may influence such ...


Utility-Scale Solar Photovoltaic Hosting Potential Of Historic Mill Sites In Humboldt County, California, Michael Avcollie Jan 2018

Utility-Scale Solar Photovoltaic Hosting Potential Of Historic Mill Sites In Humboldt County, California, Michael Avcollie

HSU theses and projects

The adoption of Redwood Coast Energy Authority’s (RCEA’s) Community Choice Energy program in May of 2017 across Humboldt County has sparked interest in locally produced energy from solar photovoltaics (PV). RCEA has a goal of bringing 5 Megawatts (MW) of local, utility-scale, solar PV under contract by 2018 and 15 MW by 2023. Humboldt County’s former mill sites offer features that make them suitable for hosting PV development. This study performed an inventory and analysis of these sites to answer two questions: Can Humboldt County’s former mill sites provide the hosting capacity for15 MW of local ...


A Decision Support Tool For Building Integrated Renewable Energy Microgrids Connected To A Smart Grid, Damilola A. Asaleye, Michael D. Murphy, Michael Breen Nov 2017

A Decision Support Tool For Building Integrated Renewable Energy Microgrids Connected To A Smart Grid, Damilola A. Asaleye, Michael D. Murphy, Michael Breen

Dept. of Process, Energy & Transport Engineering

The objective of this study was to create a tool that will enable renewable energy microgrid (REμG) facility users to make informed decisions on the utilization of electrical power output from a building integrated REμG connected to a smart grid. A decision support tool for renewable energy microgrids (DSTREM) capable of predicting photovoltaic array and wind turbine power outputs was developed. The tool simulated users’ daily electricity consumption costs, avoided CO2 emissions and incurred monetary income relative to the usage of the building integrated REμG connected to the national electricity smart grid. DSTREM forecasted climate variables, which were used ...


Testing The Feasibility Of A Bladeless Wind Turbine Design, Chukwuemeka C. Ibebuike, Hauke Busch Apr 2017

Testing The Feasibility Of A Bladeless Wind Turbine Design, Chukwuemeka C. Ibebuike, Hauke Busch

Georgia College Student Research Events

In this era of increased global warming, the immediate reduction of CO2 emission is of great importance to the survival of humanity. Wind power can go a long way to offer a better alternative to generate sustainable power without producing any CO2 gas. The reductions of CO2 emissions are of significant importance to humanity. Wind power can offer a better alternative to generate sustainable power without producing CO2. Traditional turbines consist of rotating blades while a Bladeless turbine would significantly simplify the design. This would offer possible improvements such as cost savings, reduction of the operating noise level, simplification of ...


Preface-Jes Focus Issue On Electrolysis For Increased Renewable Energy Penetration, B. Pivovar, M. Carmo, K. Ayers, X. Zhang, J. O'Brien Oct 2016

Preface-Jes Focus Issue On Electrolysis For Increased Renewable Energy Penetration, B. Pivovar, M. Carmo, K. Ayers, X. Zhang, J. O'Brien

Mechanical & Aerospace Engineering Faculty Publications

(First paragraph) Today represents a particularly exciting time, as our planet’s energy system is undergoing major changes due to dramatically decreasing renewable energy prices and increasing societal concerns over greenhouse gas emissions, criteria pollutants (arsenic, mercury, NOx, particulate matter), and climate change. These factors are pushing society toward deep decarbonization of our energy system, perhaps the most challenging issue facing the planet today. Unfortunately, wind and solar energy, while both promising generation sources, come with intermittency challenges and have limitations in their abilities to impact industrial and transportation sector demands where fossil fuel energy carriers based on chemical bonds ...


High Tech High Touch: Lessons Learned From Project Haiti 2011, Yan Tang, Marc Compere, Yung Lun Wong, Jared Anthony Coleman, Matthew Charles Selkirk Sep 2016

High Tech High Touch: Lessons Learned From Project Haiti 2011, Yan Tang, Marc Compere, Yung Lun Wong, Jared Anthony Coleman, Matthew Charles Selkirk

Marc Compere

In this paper, we will share our experiences and lessons learned from a design project for providing clean water to a Haitian orphanage (Project Haiti 2011). Supported by funds from a renewable energy company and the university president’s office, five engineering students and two faculty members from Embry-Riddle Aeronautical University successfully designed and installed a solar powered water purification system for an orphanage located in Chambellan, Haiti. This paper discusses the unique educational experiences gained from unusual design constraints, such as ambiguity of existing facilities due to limited communication, logistics of international construction at a remote village location, and ...


Effects Of Emf Emissions From Undersea Electric Cables On Coral Reef Fishes, Robert F. Jermain Jul 2016

Effects Of Emf Emissions From Undersea Electric Cables On Coral Reef Fishes, Robert F. Jermain

HCNSO Student Theses and Dissertations

The objective of this project was to determine if the electromagnetic field (EMF) emissions from undersea power cables impacted the local and transient marine life, with an emphasis on reef fishes. The work was done at South Florida Ocean Measurement Facility of Naval Surface Warfare Center, Carderock Division, Broward County, Florida. This facility functions as the hub for a range of active undersea detection and data transmission cables. It has multiple active submarine power cables that extend several miles offshore and which can deliver power and enable data transmission to and from a range of acoustic and EMF sensors. The ...


Renewable Energy Transition: Dynamic Systems Analysis, Policy Scenarios, And Trade-Offs For The State Of Vermont, Christopher Ernest Clement Jan 2016

Renewable Energy Transition: Dynamic Systems Analysis, Policy Scenarios, And Trade-Offs For The State Of Vermont, Christopher Ernest Clement

Graduate College Dissertations and Theses

There is broad consensus that a transition to renewable energy and a low-carbon economy is crucial for future development and prosperity, yet there are differing perspectives on how such a transition should be achieved. The overarching goal of this dissertation, which is comprised of three interrelated studies, is to analyze and compare energy futures scenarios to achieve a renewable energy transition and low-carbon economy in the State of Vermont. In the first study, an analysis is presented of the role of energy pricing regimes and economic policy in the context of pursuing a renewable energy transition in the State of ...


Process Design, Dynamics, And Techno-Economic Analysis Of A Sustainable Coal, Wind, And Small Modular Nuclear Reactor Hybrid Energy System, Kyle Lee Buchheit Jan 2015

Process Design, Dynamics, And Techno-Economic Analysis Of A Sustainable Coal, Wind, And Small Modular Nuclear Reactor Hybrid Energy System, Kyle Lee Buchheit

Doctoral Dissertations

"The availability of cheap electricity is one of the biggest factors for improving quality of life. With the debate on the effects of carbon dioxide emissions continuing, several countries have either implemented or are considering the reduction of emissions through various economic means. The inclusion of a monetary penalty on carbon emissions would increase the prices of electricity produced by carbon-based sources. The push for large-scale renewable sources of energy has met problems with regards to energy storage and availability. The proposed coal, wind, and nuclear hybrid energy system would combine a renewable energy source, wind, with traditional and stable ...


Strength Performance Of Iowa Soils Stabilized With Biofuel Industry Co-Product, Halil Ceylan, Sunghwan Kim, Ali Ulvi Uzer, Bo Yang Jan 2015

Strength Performance Of Iowa Soils Stabilized With Biofuel Industry Co-Product, Halil Ceylan, Sunghwan Kim, Ali Ulvi Uzer, Bo Yang

Civil, Construction and Environmental Engineering Publications

The increasing cost and depletion of fossil-based energy combined with the problems of global warming is driving the development of bio-based energy products from plant biomass as renewable energy. The utilization of biofuel co- product (BCP) in new industrial applications should be investigated to increase the profitability of bio-based products and the bio-energy business. One such area of high-impact application is the stabilization of low quality roadbed soils with sulfur-free lignins found in BCPs. Recently, researchers are taking interest in investigating the viability and use of biofuel derived sulfur-free lignins for soil stabilization.

This study aims to investigate the utilization ...


Life Cycle Assessment Projection Of Photovoltaic Cells: A Case Study On Energy Demand Of Quantum Wire Based Photovoltaic Technology Research, Shilpi Mukherjee Dec 2014

Life Cycle Assessment Projection Of Photovoltaic Cells: A Case Study On Energy Demand Of Quantum Wire Based Photovoltaic Technology Research, Shilpi Mukherjee

Theses and Dissertations

With increasing clean-energy demand, photovoltaic (PV) technologies have gained attention as potential long-term alternative to fossil fuel energy. However, PV research and manufacture still utilize fossil fuel-powered grid electricity. With continuous enhancement of solar conversion efficiency, it is imperative to assess whether overall life cycle efficiency is also being enhanced. Many new-material PV technologies are still in their research phase, and life cycle analyses of these technologies have not yet been performed. For best results, grid dependency must be minimized for PV research, and this can be accomplished by an analytical instrument called Life Cycle Assessment (LCA).

LCA is the ...


Design Of A High Temperature Subsurface Thermal Energy Storage System, Qi Zheng May 2014

Design Of A High Temperature Subsurface Thermal Energy Storage System, Qi Zheng

All Theses

Solar thermal energy is taking up increasing proportions of future power generation worldwide. Thermal energy storage technology is a key method for compensating for the inherent intermittency of solar resources and solving the time mismatch between solar energy supply and electricity demand. However, there is currently no cost-effective high-capacity compact storage technology available (Bakker et al., 2008). The goal of this work is to propose a high temperature subsurface thermal energy storage (HSTES) technology and demonstrate its potential energy storage capability by developing a solar-HSTES-electricity generation system. In this work, main elements of the proposed system and their related state-of-art ...