Electric Vehicles Essay Example for Free

Electric Vehicles Essay Skyrocketing fuel pricing along with depleting oil resources and increased environmental concerns have pushed mankind to consider alternative sources of fuel to power automobiles. Among all the alternate fuel ideas that include everything from excreta to biodiesel, electricity has also been considered as a best alternative to conventional fuels. Electric Vehicles (EVs) are a promising technology for drastically reducing the environmental burden of road transport. Electric Vehicles (EVs) have been around since mid 1800s. During early years, electric vehicles had many advantages over cars powered by internal combustion engines. Such as vehicles with internal combustion engines were started using a hand crank, whereas EVs could be started like regular cars today. EVs did not have gearboxes or the noise and vibration levels of a petrol-powered car. However, their expensive price tag and limited range led petrol powered car to prosper. However later, rising fuel prices, limited oil resources and environmental concerns brought the electric car back into mainstream production line for automobiles. Today, almost all mainstream car makers have been building electric concept cars as well as production version of electric and hybrid cars. Introduction: An automobile that is powered entirely or partially by electricity are electric vehicles. Electric cars are the cleanest, most efficient, and most cost-effective form of transportation around. Seriously, electric cars are high-performance vehicles that will continue to meet new challenges in the future. There are generally of three types: Battery Electric Vehicle: A battery electric vehicle runs entirely on an electric motor, powered by a battery. The battery is charged through an electrical outlet. One of it is Nissan Leaf . Plug-In Hybrid Electric Vehicle: A plug-in hybrid vehicle has both an electric motor and a gasoline engine onboard. These vehicles generally run on the electric motor until the battery is depleted, at which point the gas engine can kick in, extending the car’s range. The main battery in a plug-in hybrid is charged through an electrical outlet. An example of a plug-in hybrid is the Chevrolet Volt. Hybrid Electric Vehicle: A typical hybrid electric vehicle is fuelled by gasoline and uses a battery-powered motor to improve efficiency, thus is not considered a plug-in electric vehicle. The battery in a gasoline hybrid is never plugged into an electrical outlet, but instead is powered by a combination of the gasoline engine and regenerative braking. The most well known hybrid electric vehicle is the Toyota Prius. WORKING OF ELECTRIC VEHICLES: A. Battery Electric Vehicles(BEV’s) Electric cars are zero-emission cars at the point of their usage. There are two types of charger plugs in BEV’s. One is quick charger plug which charges the battery at faster rate compared to the household charger plugs. On board chargers are used to convert AC power to DC power. The controller controls the amount of power to be transmitted to the motor, which in turn, converts the electrical power to the motive power. Nickel-Metal Hydride and Lithium-ion cells are the latest battery modes used nowadays. B. Hybrid Electric Vehicles Hybrid electric vehicles combines the best features of conventional as well as electrical cars. The underlying principle of hybrid cars comprises of the usage of temporary power storage which later on enables the major engine to be functioned at the close to its supreme efficiency. There are two types of hybrid drive generated series hybrids and parallel hybrids. In ‘series hybrid’, the combustion engine sends the power to the electrical generator. Electrical generator converts the mechanical energy into electrical energy which is converted into DC by the inverter to be stored in the battery. Power from the battery can be inverted back to AC so that the electric motor converts it into motive power. In parallel hybrid the car wheels are either powered by engine or from the battery powered electric drive-train. Planetary gear system is used to transmit the power into axle. Electric motors and planetary gear system work as a Continuously Variable Transmission(CVT). In both the hybrids, whenever the engine ignites slowly, the excess energy is stored for the later usage. In this way, these cars provide less emission and improved fuel economy. Conventional Cars Vs Electric Vehicles A. Fuel Efficiency In a conventional car: . * 87. 4 % of fuel energy is wasted * Only 12. 6 % of fuel energy is transferred to the wheels * 5. 8 % is turned to kinetic energy, consumed in the brake * 17. 2 % idling losses, engine on with no torque How Hybrids save fuel? 1. Engine is turned off at: -Stops -Lower speed (say less that 15 km/h), an electric motor drives the car until speed reaches a certain limit, then engine kicks in -When vehicle is stopping or going downhill, engine is turned off, and regenerative braking is applied. 2. When engine operates in an inefficient mode(e. g. at very high or very low engine speeds), the electric motor kicks in and assists engine. Engine is driven to its optimum operating zone 3. Engine can be made smaller, due to electric motor assistance B. Emissions: 1. In combustion engine, emissions occur during driving 2. In E-cars, emission occurs only during electricity production. C. Operating Cost 1. In combustion cars, take petrol at Rs. 73/lt, and a car that achieves 25kms/lt. Energy cost is Rs3/km. 2. Now take electricity at Rs. 6/kW-h, and a car that consumes 125 W-h/km. Energy cost is Rs. 0. 75/km D. Efficiency ratio: 1 Combustion engine: 25-30 percent 2. Electric motor: close to 90 percent TECHNOLOGICAL CHALLENGES AND OPPORTUNITIES: The main problem with the electric car is battery. Such as:- Time of battery charging is long. -Batteries are heavy. -Batteries are expensive. -Low performance in hot or cold temperatures also may damage the battery -Very sensitive to overcharge/undercharge(Battery life reduces dramatically) -Contain toxic heavy metals, disposal issue. All these provide scope for the further research and development in the field of electric vehicles. The RD are supported by the government and industries. POSSIBLE FUTURE TECHNOLOGIES: Over population and limited energy resources have pushed the need and the demand of the electric vehicles. In the future, we will have hybrids and battery electric vehicles everywhere in the markets, industries and highways. Some of the possible future technologies in this field are: 1. A photovoltaics-carport (solar service station) which is considered as a charging station of electric cars for the future. 2. Battery recharging which will employ a special chemical process, occurring on all energy-storage particles at once; in contrast to the traditional batteries, where only a fraction of the energy storage can be replenished at once . 3. Electrical outlet and electric cable will not be required in future anymore, because the electric car of the future refuels its power fully automatically and without contacting by induction while driving or parking. CONCLUSION: Electric vehicles (EVs) hold the potential of transforming the way the world moves. EVs can increase energy security by diversifying the fuel mix and decreasing dependence on petroleum, while also reducing emissions of greenhouse gases and other pollutants. Just as important, EVs can unlock innovation and create new advanced industries that spur job growth and enhance economic prosperity. However, the mass deployment of EVs will require transportation systems capable of integrating and fostering this new technology. To accelerate this transitition, cities and metropolitan regions around the world are creating EV-friendly ecosystems and building the foundation for widespread adoption.

Application of CFD Simulation for Evaluating the Separation Efficiency of Deoiling Hydrocyclones :: Environment, Oil-water Separation

Introduction Having an efficient and reliable system for oil-water separation is of crucial importance especially for offshore oil and gas industry. Due to the platform movement, space, weight and operating limitations in offshore, the usage of common methods (gravity based vessels) for oil/water separation are ineffective. On the other hand producing oil is often accompanied by large amount of water that is discharged into the sea on offshore platforms. The amount of oil in water is confined from environmental standards. Therefore the need to have a high efficiency compact separator during variable operating conditions attracts the interests of researchers to hydrocyclones. Special trait of hydrocyclones such as simple design, easy to install and operate, no moving parts, and low manufacturing and maintenance costs make hydrocyclones as an economical and effective system for produced water treatment [1-2]. The separation process that is occurred in the deoiling hydrocyclones is quite different from that in the desander ones []. The density difference between liquid-liquid is smaller than solid-liquid mixtures. Therefore the separation of liquid from liquid is more difficult than solid from liquid and needs higher rotational speeds. The liquid droplet in comparison with solid particles could not experience shear rates. If the shear rates increase to the critical level the larger droplet break down to the smaller ones. The separation process for small liquid droplets is more difficult than large ones. On the other hand if two droplets close enough they might coalesce to each other. Because of difference in flow split of desander and deoiler hydrocyclones, the flow feature of continuous phase is different in these two types. The centrifugal forces cause the solid particles migrate to the wall region in desander hydrocyclones. So the near wall region is important in desander hydrocyclones but the oil droplet migrate to the center of hydrocyclones in deoiling hydrocyclones and the consideration tends to the center flow features. The first idea of using common hydrocyclones for oil-water separation was suggested by Simkin and Olney [6] and Sheng et al. [7] but fundamental studies on deoiling hydrocyclones started from 1980 by Colman [8] and Thew. Several experimental researches on deoiling hydrocyclones were conducted by Colman et al. [9] and Colman and Thew [10-12]. Their results showed that the separation efficiency of hydrocyclones is independent of flow split between 0.5 to 10 percent. So the overflow diameter should design based on working conditions. Moreover for constant droplet size distribution in inlet, the size distribution in outlet is independent of flow split. Application of CFD Simulation for Evaluating the Separation Efficiency of Deoiling Hydrocyclones :: Environment, Oil-water Separation Introduction Having an efficient and reliable system for oil-water separation is of crucial importance especially for offshore oil and gas industry. Due to the platform movement, space, weight and operating limitations in offshore, the usage of common methods (gravity based vessels) for oil/water separation are ineffective. On the other hand producing oil is often accompanied by large amount of water that is discharged into the sea on offshore platforms. The amount of oil in water is confined from environmental standards. Therefore the need to have a high efficiency compact separator during variable operating conditions attracts the interests of researchers to hydrocyclones. Special trait of hydrocyclones such as simple design, easy to install and operate, no moving parts, and low manufacturing and maintenance costs make hydrocyclones as an economical and effective system for produced water treatment [1-2]. The separation process that is occurred in the deoiling hydrocyclones is quite different from that in the desander ones []. The density difference between liquid-liquid is smaller than solid-liquid mixtures. Therefore the separation of liquid from liquid is more difficult than solid from liquid and needs higher rotational speeds. The liquid droplet in comparison with solid particles could not experience shear rates. If the shear rates increase to the critical level the larger droplet break down to the smaller ones. The separation process for small liquid droplets is more difficult than large ones. On the other hand if two droplets close enough they might coalesce to each other. Because of difference in flow split of desander and deoiler hydrocyclones, the flow feature of continuous phase is different in these two types. The centrifugal forces cause the solid particles migrate to the wall region in desander hydrocyclones. So the near wall region is important in desander hydrocyclones but the oil droplet migrate to the center of hydrocyclones in deoiling hydrocyclones and the consideration tends to the center flow features. The first idea of using common hydrocyclones for oil-water separation was suggested by Simkin and Olney [6] and Sheng et al. [7] but fundamental studies on deoiling hydrocyclones started from 1980 by Colman [8] and Thew. Several experimental researches on deoiling hydrocyclones were conducted by Colman et al. [9] and Colman and Thew [10-12]. Their results showed that the separation efficiency of hydrocyclones is independent of flow split between 0.5 to 10 percent. So the overflow diameter should design based on working conditions. Moreover for constant droplet size distribution in inlet, the size distribution in outlet is independent of flow split.

Explaining legal and ethical tensions between maintaining confidentiality and sharing information

Explain how to support effective communication within your own job role. Communication is constantly happening within the day care center and in my job role I have a responsibility to communicate with staff, service users and other professionals. I use various forms of communication but I also seek to make sure that it is understood. Communication has got to be understood before it can be effective and so I try to ensure comprehension when I am verbally speaking by getting staff to repeat what I have asked them to do. I also write simply worded memos and emails to ensure ease of comprehension.When communicating with other professionals I speak clearly and seek affirmation when organizing meetings or planning events. I also seek to write in a legible manner if writing to professionals. Each service user has a communication book for reporting and informing families and carers of activities on a daily basis, these are written in a legible way also. Primarily when communicating with each individual service user I seek to communicate in an understandable way and at a level each individual will understand. The methods I employ are verbal, pictorial, object-based, physical prompts and signing.Analyse the barriers and challenges to communication within own job role. Propose improvements to communication systems and practices to address any shortcomings. Lead the implementation of revised communication systems and practices. Barrier/Challenge. Explaination. How could it be improved? How have I improved it Deafness? Some of our service users have hearing loss and on occasions forget to bring their hearing aids to day care. This presents a severe communication challenge and barrier on these occasions.Bring hearing aid in daily. I have written a request in service user’s communication book requesting that hearing aids are sent in daily and suggesting that a spare is obtained in the event that his current hearing aid is broken. Visual impairments mean that visual cue s and prompts are meaningless and this includes signing. Glasses could be worn. I have requested that service users wear their glasses to aid with communication. I have adapted general approach to service users to compensate for blindness. No Speech/Speech Impediments. Some of our service users have poor speech or no speech at all. With these service users an alternative form of communication is required or an ability to listen  intently and comprehend what they are saying. Picture/objects of reference.A jotter and pen to spell difficult words.For some of our service users I have drawn together objects and photographs of reference and each one acts as a word of vocabulary and provides an ability to communicate effectively. For one of my service users I have encouraged him to spell out difficult words to understand. Comprehension. Some of our service users have profound learning disabilities and their level of comprehension and understanding is very limited, however they communicat e constantly.Alternative methods could be sought.One individual has been taught to â€Å"eye-point† at what she wants. Another gets quite restless and verbal when he is upset and smiles and giggles when happy. Staff have been informed of how this service user communicates. Time Another challenge to effective communication in the day care center is time. We are all busy and we don’t always have the time to listen and to communicate the way we should.Better time management.Managing our workload allows us to take time with our service users. However on many occasions there is no solution as we are all busy and things need to be completed. Noise. One of the biggest preventatives and barriers to effective communication is noise. Is the music too loud? Is the television on? Is there too many people in the room talking? Turn music/TV volume down, close doors, ensure staff have a relevant reason for being in the day care room.I have ensured volume of music etc. is at an accept able level.I have told staff to leave the day care room or to stop talking so loudly to enable the preservation of an environment conducive to effective communication. Distance. When communicating with service users or staff members at the other side of the room or down the corridor distance and space apart can become a barrier and a challenge to effective communication. Go to the individual you are communicating with. Although it is not always possible it is advisable to go to the individual and I seek to do this as much as possible. Computer System/E-mail. When sending or receiving e-mails it is necessary to have access to a working computer which is ‘online’.Have various ‘backups’ when communicating via email. I have sent emails and to ensure that the information has been forwarded I have  sent hard copies too.

Book Review Darwins Black Box by Michael Behe

Darwins Black Box (Order #A2089774) Every since the publication of the Origins of Species in 1859, the theory of evolution has been generally accepted by scientists around the world, that is, until 1996 when Michael Behe published his book Darwins Black Box, calling the theory of evolution into question. The theory of evolution states that individual single point mutations in DNA give rise to the development of new characteristics in species. If these new characteristics are advantageous for survival, then the genes are passed down to new generations. As these characteristics are accumulated, new species develop. However, while most scientists have accepted evolution as a scientific fact, they have yet to answer some basic fundamental questions about the process itself. Michael Behe points to this and proposes that the reason scientists do not yet have all the answers regarding the processes behind evolution is because they have failed to see the intelligent design that lies within it. The author asserts that the data of biochemistry argues strongly that many molecular machines in the cell could not have arisen through a step-by-step process of natural selection ¦much of the molecular machinery in the cell is irreducibly complex. (Bohlin, 2000, p. 103) In order to understand Behes argument, the concept of irreducible complexity must be discussed. The author defines irreducible complexity as a single system composed of several well-matched, interacting parts thatShow MoreRelated Teaching Origins in 20th Century American Public Schools Essay6390 Words   |  26 Pagesselection; through this process, species change over time, including extinction and the creation of new species. Darwin presented evidence observed in his time as a naturalist aboard the Beagle and evidence collected by other naturalists and breeders. Darwin’s breakthrough in understanding the history of life was built upon the understanding that geologists and other naturalists, like Cuvier, Lamarck, and Wallace, had developed of the Earth as an old planet that had seen many changes in environmental conditions