You're using an outdated browser. Please upgrade to a modern browser for the best experience.
Subject:
All Disciplines Arts & Humanities Biology & Life Sciences Business & Economics Chemistry & Materials Science Computer Science & Mathematics Engineering Environmental & Earth Sciences Medicine & Pharmacology Physical Sciences Public Health & Healthcare Social Sciences
Sort by:
Most Viewed Latest Alphabetical (A-Z) Alphabetical (Z-A)
Filter:
All Topic Review Biography Peer Reviewed Entry Video Entry
Topic Review
Fuel Cells
Fast start-up, high efficiency, no toxic emissions into the atmosphere and good modularity are the key advantages of fuel cell applications. Despite the merits associated with fuel cells, the high cost of the technology remains a key factor impeding its widespread commercialization.
  • 1.8K
  • 13 Jan 2021
Topic Review
Produced Water Treatment
Flowback-produced water (FP) is a waste fluid associated with hydraulic fracturing in unconventional oil and gas development (UOG). Initially, FP reflects the composition of the hydraulic fracturing fluid, which is referred as flowback water (FBW). After the initial months of well production, the waste fluid is predominantly representative of the formation and is known as produced water (PW). 
  • 1.8K
  • 08 Jul 2022
Topic Review
Technical and Economic Viability of Underground Hydrogen Storage
The concept of underground hydrogen storage (UHS) is less known than its natural gas counterpart, which is expected due to its less significant role in the past. Despite this, the insights gained with natural gas can be applied to hydrogen storage due to the shared cavern design and operation.
  • 1.8K
  • 11 Dec 2023
Topic Review
Hydrogen Production by Wastewater Alkaline Electro-Oxidation
The electro-oxidation of olive mill and biodiesel wastewaters in an alkaline medium with the aim of hydrogen production and simultaneous reduction in the organic pollution content are presented. The process is performed, at laboratory scale, in an own-design single cavity electrolyzer with graphite electrodes and no membrane. The system and the procedures to generate hydrogen under ambient conditions are described. The gas flow generated is analyzed through gas chromatography. The wastewater balance in the liquid electrolyte shows a reduction in the chemical oxygen demand (COD) pointing to a decrease in the organic content. The experimental results confirm the production of hydrogen with different purity levels and the simultaneous reduction in organic contaminants. This wastewater treatment appears as a feasible process to obtain hydrogen at ambient conditions powered with renewable energy sources, resulting in a more competitive hydrogen cost.
  • 1.8K
  • 15 Sep 2022
Topic Review
Iron Ore Reduction with Hydrogen
The steel industry represents about 7% of the world’s anthropogenic CO2 emissions due to the high use of fossil fuels. The CO2-lean direct reduction of iron ore with hydrogen is considered to offer a high potential to reduce CO2 emissions, and this direct reduction of Fe2O3 powder is investigated in this research.
  • 1.8K
  • 18 Sep 2021
Topic Review
Exploration and Use of Lithium in Oman
Oman has huge potential for lithium exploitation and production, considering the enormous quantities of spodumene and seawater salt with high-grade lithium available, developing efficient regulations and rules to protect investors’ rights, and reducing the environmental risks associated with the production and recycling of lithium-ion batteries. 
  • 1.8K
  • 29 Jan 2024
Topic Review
Methanol as a Marine Fuel
Methanol is efficient and cost-effective and excels over marine gasoil (MGO), especially in new ships. It is economically advantageous, with decreasing investment costs compared to liquefied natural gas (LNG), while providing flexibility without specialized pressure tanks. Global marine fuel trends prioritize fuel traits, accessibility, and environmental considerations, incorporating factors like policies, emissions, bunkering, and engine adaptability during transitions.
  • 1.8K
  • 02 Feb 2024
Topic Review
Energy Recovery in Road Vehicles
The main reasons for reducing energy losses in motor vehicles is to reduce the fuel consumption of motor vehicles and thus reduce emissions, reducing the consumption of consumables and increasing the efficiency and reliability of vehicles. Part of the recovered lost energy can be used to cover the demand of other vehicle electronic systems. Automotive energy harvesting systems are usually employed to increase overall vehicle efficiency. The main directions of recovery of energy lost in vehicles are heat energy losses, the energy obtained from the vehicle braking process and the energy derived from damping vibrations in the vehicle suspension system. 
  • 1.8K
  • 16 May 2023
Topic Review
Perovskite Solid-State Electrolytes for Lithium Metal Batteries
Solid-state lithium metal batteries (LMBs) have become increasingly important in recent years due to their potential to offer higher energy density and enhanced safety compared to conventional liquid electrolyte-based lithium-ion batteries (LIBs). However, they require highly functional solid-state electrolytes (SSEs) and, therefore, many inorganic materials such as oxides of perovskite La2/3−xLi3xTiO3 (LLTO) and garnets La3Li7Zr2O12 (LLZO), sulfides Li10GeP2S12 (LGPS), and phosphates Li1+xAlxTi2−x(PO4)3x (LATP) are under investigation. Among these oxide materials, LLTO exhibits superior safety, wider electrochemical window (8 V vs. Li/Li+), and higher bulk conductivity values reaching in excess of 10−3 S cm−1 at ambient temperature, which is close to organic liquid-state electrolytes presently used in LIBs. 
  • 1.7K
  • 23 Nov 2021
Topic Review
Wave Energy Generation in Brazil
Seas and oceans offer great potential as a widely available source of clean and renewable energy near high energy consumption centers. This source of energy is a valuable option in the energy transition and in energy matrix decarbonization. Wave energy and an oscillating water column (OWC) device stand out as the types of ocean energy with the most potential. An onshore OWC requires locations with rocky outcrops and steeper slopes as the device needs to be physically installed and has lower energy dissipation due to friction with the seabed. However, Brazil has approximately 7490 km of coastlines, with various shoreline geometries and geomorphologies, some of which are very suitable for OWC implementation.
  • 1.7K
  • 27 Oct 2023
Topic Review
Commercialization of Electric Vehicles
Electric Vehicles (EVs) are a promising alternative to internal combustion engine vehicles as the city is transitioning to clean energy.
  • 1.7K
  • 10 Feb 2022
Topic Review
Green and Blue Hydrogen Production in Colombia
Hydrogen is the most abundant element in nature, but it cannot be considered an energy source by itself because it is impossible to find it in its elemental form in nature. Colombia, a privileged country in terms of diversity, availability of natural resources, and geographical location, has set a roadmap for hydrogen as part of the energy transition plan proposed in 2021. To reduce its emissions in the mid-term and foster its economy, hydrogen production should be green and blue, with specific targets set for 2030 for the hydrogen costs and produced quantities. A comparison is made concerning the state-of-the-art production of blue and green hydrogen and how Colombia performs in each pathway.
  • 1.7K
  • 30 Nov 2022
Topic Review
Hybrid Renewable Energy System
The HRES is a cyber–physical system that can be divided into two layers: the power infrastructure and the communication infrastructure layers, as shown in Figure 1. The power infrastructure layer consists of different energy sources (e.g., wind turbines, photovoltaics, diesel generators, and batteries), transformers, feeders, converters, and electrical connections. The communication infrastructure layer supports the physical infrastructure by an underlying communication network, linking between sensors and actuators nodes. This enables the local control center to manage the system operation. In this integration, ICTs play an essential role in allowing the transition from the conventional power grid to the future smart grid by supporting the integration of HRES.
  • 1.7K
  • 06 Sep 2021
Topic Review
Building Energy Modeling Approaches
Buildings use up to 40% of the global primary energy and 30% of global greenhouse gas emissions, which may significantly impact climate change. Heating, ventilation, and air-conditioning (HVAC) systems are among the most significant contributors to global primary energy consumption and carbon gas emissions. Extensive research and advanced HVAC modeling/control techniques have emerged to provide better solutions in response to the issues.
  • 1.7K
  • 26 Oct 2022
Topic Review
Hydrogen Energy
This entry explains why the 'hydrogen economy' has been so slow in coming, despite the abundance of hydrogen (H2) on Earth. H2 is either bound up with oxygen in water, or with carbon in fossil fuels, which release CO2 on combustion. For several decades, hydrogen-powered vehicles using fuel cells were seen as the major opportunity for H2. But if H2 is produced from fossil fuels, its use makes little contribution to climate change mitigation, and in any case, electric vehicles are now the main challengers to oil for powering transport. H2 will only come into its own when intermittent renewable energy, mainly wind and solar energy, dominate energy supply, as it makes sense to convert surplus power to H2 for storage or immediate use.  
  • 1.7K
  • 04 Jan 2021
Topic Review
Perovskite Solar Cell
Organic-inorganic hybrid perovskite materials have attracted tremendous attention as a key material in various optoelectronic devices. Distinctive optoelectronic properties, such as a tunable energy band position, long carrier diffusion lengths, and high charge carrier mobility, have allowed rapid progress in various perovskite-based optoelectronic devices (solar cells, photodetectors, light emitting diodes (LEDs), and lasers). Interestingly, the developments of each field are based on different characteristics of perovskite materials which are suitable for their own applications. 
  • 1.7K
  • 20 Jan 2021
Topic Review
Power Battery Thermal Management System
The battery thermal management system is a key skill that has been widely used in power battery cooling and preheating. It can ensure that the power battery operates safely and stably at a suitable temperature.
  • 1.7K
  • 28 Mar 2022
Topic Review
Time Series Aggregation for ESMs
Due to the high degree of intermittency of renewable energy sources and the growing interdependences amongst formerly separated energy pathways, the modeling of adequate energy systems is crucial to evaluate existing energy systems and to forecast viable future ones. However, this corresponds to the rising complexity of energy system models (ESMs) and often results in computationally intractable programs. To overcome this problem, time series aggregation is frequently used to reduce ESM complexity. As these methods aim at the reduction of input data and preserving the main information about the time series, but are not based on mathematically equivalent transformations, the performance of each method depends on the justifiability of its assumptions.
  • 1.7K
  • 29 Sep 2021
Topic Review
Indoor Thermal Comfort
A neutral or comfortable environment is an environment that allows metabolic heat production to be balanced with heat exchange (loss and/or gain) from the air around the worker. Outside this situation of balance, there may be adverse situations in which the exchange of heat energy constitutes a risk to the person’s health, since even taking into account the body’s thermoregulation mechanisms, they cannot maintain a constant and adequate internal temperature. Even though the milder climate scenario and constant evolution of thermal building regulation are in light of European initiatives, in Portugal, there are few houses where occupants can remain all the time in perfectly comfortable temperature conditions without resorting to heating or cooling. According to the Long Term Strategy for the Renewal of Buildings (ELPRE), this results from the combination of several factors, namely, low energy use for air conditioning compared to energy needs and aged building stock with poor energy performance. In fact, around 70% of the dwellings currently certified have low energy efficiency (C or less).
  • 1.7K
  • 01 Sep 2022
Topic Review
Flow Field Design of PEMFC
Climate change and the major threat it poses to the environment and human lives is the major challenge the world faces today. To overcome this challenge, it is recommended that future automobiles have zero carbon exhaust emissions. Even though battery electric vehicles reduce carbon emissions relative to combustion engines, a carbon footprint still remains in the overall ecosystem unless the battery is powered by renewable energy sources. The proton exchange membrane fuel cell (PEMFC) is an alternate source for automotive mobility which, similar to battery electric vehicles, has zero carbon emissions from its exhaust pipe. Moreover, the typical system level efficiency of a PEMFC is higher than an equivalent internal combustion powertrain.
  • 1.7K
  • 27 Sep 2023
  • Page
  • of
  • 33
Featured Entry Collections
>>

Featured Books

>>
Encyclopedia of COVID-19
Encyclopedia of Engineering
Encyclopedia of Social Sciences
Encyclopedia of Digital Society, Industry 5.0 and Smart City
Academic Video Service
Feedback