Energy-Saving Techniques in Engineering Essay Sample

Renewable Energy and the Environment

Engineering as one of the most power-consuming branches of human activity requires a gradual change in energy use. In this paper, I aim to discuss the modern ways of renewable energy and energy-saving techniques use in engineering and reveal the scopes of its future use.

Executive Summary

Engineering is a branch of human intellectual activity in the application of science to solve specific problems of mankind. This is accomplished through the use of both scientific knowledge and practical experience (engineering skills, abilities) to design useful (mostly technical) processes and technical objects that implement such processes. Mainly, engineering is used for technological and industrial purposes. Therefore, it requires large amount of energy to maintain complicated and power-consuming processes. By means of power, engineering provides people with all the common comforts of life. Obviously, in spite of great changes happening in the world’s energy consumption area, engineering is the main field to undergo changes. It is important in terms of giving a new burst of development and providing mankind with the ability to design new comforts and technologies. Common means of power are too old and non-efficient to be used in technological areas controlled by engineering. I aim to discuss energy-saving techniques used in the following main areas of engineering: chemical, electrical, civil and mechanical. These areas, as the most attributed to gradual change and development, are to use energy-saving technologies most extensively. Therefore, this paper is aimed to discuss the already existing energy-saving means as well as scopes for future use and development of the mentioned technologies in the engineering field.

Introduction and Background

Modern engineering activity is directly aimed at solving technical problems and appliances. Technology is the only thing that unites all engineers (Abdelaziz, Saidur, & Mekhilef, 2011). The main problem here is that with a growing demand of people for new comforts, technologies and appliances, the power consumed by all engineering branches grows proportionally (Abdelaziz, Saidur, & Mekhilef, 2011). From the times when horses were the main source of power, the demand for energy in engineering increased by 20 times and continues growing every year (Bose, 2010). In spite of reduce in natural resources and relatively low efficiency of common means of energy as almost 65 % of common energy is dissipated as heat (Dieleman, & Hemming, 2009), the necessity for change is obvious. Factories, plants, enterprises and industrial facilities continue installing more equipment to fit the demand for technical goods; more and more robots and technical appliances are used in engineering. Thus, situation means that engineering facilities require more energy every day. Therefore, energy-saving technologies and renewable energy use are essential for further growth of engineering.

Discussion of the Issue

Engineering is rather wide and comprehensive part of human activity. Nowadays, it includes almost all fields of everyday life since its main essence is the creation of something new and constant development (Abdelaziz, Saidur, & Mekhilef, 2011). However, engineering comprises four main branches: chemical, civil, electrical and mechanical engineering (Dieleman, & Hemming, 2009). The further discussion will be held separately for each branch to cover as much information as possible and to discuss in depth energy used in each branch.

Electrical Engineering

Electricity is the main force that drives all technical processes and brings them to life. Nowadays the world meets the continuously increasing demand for electricity in two ways: first is allowing a constant use of conventional natural resources, such as oil, gas, coal, etc., and building new power generation facilities. This way seems to be a dead end because of the limited stocks and relatively low efficiency of conventional power-generating techniques (Bose, 2010). Second is to focus on more efficient ways of energy resources use, energy conservation, development and spread of resource-saving technologies. The second way is obviously more efficient in a long-term perspective.

Using alternative energy sources to produce electricity is, probably, the most popular mean of energy saving. Today, the amount of solar, wind, tidal, geothermal and nuclear stations is constantly growing, turning these ways of electricity production into conventional ones and removing oil- and coal-based station off the market. For example, in Denmark wind power stations produce almost 20% percent of electric energy; in Australia almost 30 % of electric energy is produced by solar ones (Bose, 2010). In addition, the modern trend is to have domestic wind or solar stations to provide local villages or even separate houses with electricity. The usage of alternative electricity producing technologies allows saving about 10-15% of energy since these technologies are more efficient and less energy is dissipated into heat.

Moreover, use of electricity for domestic purposes is also a power-saving technique. Electricity consumption for lighting parks, waterfronts, yards, decorative lighting and advertising is accepted at a rate of 20 to 30% of the electricity consumption in an average city (Bose, 2010). More than 50% of electricity, consumed by the system of artificial lighting, is used in commercial and industrial buildings. Installation and use of the automated control systems contributes to the reduced consumption of electricity. In particular, street lighting is one of the target sectors for the implementation of intelligent energy-saving technologies – it accounts for 40% of the city budget for electricity, and smart-technology can save up to 30% of these costs (Hawkes, & Forster, 2002).

It is known that transmission and distribution of electric power in electric networks is necessarily accompanied by the loss of electricity (Bose, 2010). The decrease of energy losses is possible by means of appropriate measures. Mainly, the specificity of urban networks is that the construction of new transmission lines is associated with significant costs and often simply not possible due to dense development of a city (Hawkes, & Forster, 2002). Therefore, the increased power of the energy transferred to the existing lines saves a great amount of energy. Thus, active energy is converted into useful one: mechanical, thermal and other energy (Abdelaziz, Saidur, & Mekhilef, 2011).

Finally, the appearance of dissipative and harmful reactive power leads to an increase in power generators, transformers, power supply lead sections, as well as resistive losses and increases voltage drop. Therefore, reactive power compensators, such as reactors and different types of coils are used to compensate the reactive power and use it for further functioning of electrical equipment. Reactive power compensation in a building during one winter month managed to reduce electricity consumption by 3% and in a power-consuming industrial facility – by 10% (Renz, & Du, 2013).

Chemical Engineering

Chemical industry, of course, is one of the leading industries, the contribution of which to modern economic development cannot be underestimated. Chemical production is among the most energy-intensive. Ratio of energy here is 9%, while the average for the industry is 2.5%. With the huge cost of fuel and energy resources (FER) in the chemical industry, energy efficiency of most technologies does not exceed 30-40%, despite the relatively high yield of the desired product (Abdelaziz, Saidur, & Mekhilef, 2011). This is due to the fact that the processing of the feedstock in chemical engineering, as a rule, pays more attention only to obtaining the maximum output percent of the final product without taking into account the feasibility of energy conducted processes (Bose, 2010).

Here, the transition to continuous processes allows obtaining the increase in economic characteristics of chemical industry products. It requires less material, labor and energy costs, improves environmental indicators and leads to complex automation. Such a technique is already extensively used in the market of industrial equipment for cold production. There are energy-saving cooling units on the basis of the new scroll compressor characterized by higher energy efficiency and coefficient of performance, saving up to 30% of electricity within a relatively short payback period (Bose, 2010).

Various sources highlight the issue of rational use of energy and raw materials in relation to the production of ammonia. In particular, the performance of energy saving units of energy consumption per ton of ammonia reached 6.5-7.5 Gcal as compared with 10-12 Gcal in the 1970s (Abdelaziz, Saidur, & Mekhilef, 2011). Overall, today approximately 25% of the world production capacity of ammonia is based on the energy-saving technologies. The greatest success in this area has been achieved by Venezuela having 70.2% of energy saving capacity, Trinidad and Tobago (65.5%), Indonesia (48.8%) and the Middle East (41.1%) (Bose, 2010).

Nowadays, technical and economic calculations confirm the advantage of large-scale production, within which it is possible to reduce energy consumption by 20-30%. In this case, it is possible to reduce the consumption of materials, to reduce the area of ​​production and to increase productivity (Bose, 2010). At the same time, consolidation of capacity units creates additional prerequisites for the integration of the most advanced control systems with the use of modern means of automation, which beneficially contribute to improving the efficiency of large power units.

The concept of intensification of chemical-technological processes is to change the basic factors, which, one way or another, affect the rate of flow of the process and the output of the target products. On the other hand, processes carried out in the diffusion region can be intensified, for example, by stirring, homogenizing, selecting the optimum motion of the interacting process stream and increasing their contact surface. Additionally, improving the selectivity and activity of the catalyst by 1% in a reforming process leads to a reduction of energy consumption by 1.8%- 2.9% (Bose, 2010).

Finally, methods of integration of the basic processes of chemical technology by their mutual coupling and alignment are extensively used. Due to optimal integration of material and energy flows in the fine chemical, inorganic and petrochemicals industries it is possible to save about 30% of general energy consumption, in food production and resins – to 25%, and in pigments production – about 15% (Bose, 2010).

Civil Engineering

Previously, civil engineering techniques were aimed at quick building, not taking into account the heat dissipation due to such quick construction. However, modern construction technologies take into account not only the reliability, durability and aesthetics of an object, but also mandatory energy efficiency measures. Passive energy saving can save up to 85% of the thermal energy used for heating or cooling of a building (Hawkes, & Forster, 2002). To conserve heat, thermal wall insulation is considered the most urgent operation, and this action is perfectly acceptable in both private and for multifamily housing. The most common actions for wall insulation are internal and external insulation (Hawkes, & Forster, 2002).

One of the main steps to control the heat and power dissipation in civil engineering was the adoption of Leadership in Energy and Environmental Design (LEED), a voluntary system of green building certification of buildings, designed in 1998 by the US Green Building Council (Bose, 2010). Designing energy efficient homes is a complex process, in which one must take into account the interaction of multiple and sometimes contradictory factors. In order to keep heat inside a house, i.e. save the resource of the heating system, proper site orientation, as well as correct layout of rooms play the major role. For example, when designing the layout of the rooms with many windows facing north, a designer deprives the house of the access to natural light and heat. Therefore, to construct energy-efficient homes engineering professionals are encouraged to seek professional team able to implement the project.

The most energy-saving technology is Canadian one (frame and panel frame houses). Owner of these homes can significantly save money, as a constant temperature can be maintained in such houses in comparison to classical building technologies (for example, SIP panel buildings can save up to 60% on heating resources than a house made of bricks). Despite the fact that the technology is not new (it has been used successfully around the world for over 80 years), it is still the most energy saving (Hawkes, & Forster, 2002).

Mechanical Engineering

Mechanical engineering is related to the production of machines, engines, and power plants among others (Renz, & Du., 2013). To save energy in the production of machines and other products is to be effective, or “modern”. “Modern technology” must take into account a range of often conflicting requirements and ensure the production of machines and products with specified accuracy, reliability, and performance. These requirements include high performance and efficiency of processes, wide automation and minimization of manual labor, striving for zero waste production, safety, environmental friendliness and more. In spite of the fact that almost 60% of machinery of the world’s plants is 30 years old or older, especially in the Third World Countries, the necessity for modernization is obvious. It allows saving about 35-40% of the world`s energy (Renz, & Du., 2013).

Not only the equipment, but also the production process should be designed so as to fully comply with the relevant technologies in regard to precision, speed, reliability, durability and other parameters. Complete automation, even if it seems energy-consuming, helps to save about … % of energy due to the fact that these processes are much faster than the manual ones and help to save about .5% of energy per process (Abdelaziz, Saidur, & Mekhilef, 2011). Due to the fact that equipment is used in high-performance processes, that is working almost all the time during a working shift, modern devices are equipped with automatic contactors or/and control systems, allow turning the device off while it is off-service, saving about 1-2% of energy per shift (Renz, & Du., 2013).

Future Predictions

In conclusion, I want to talk about future perspective of energy saving techniques in engineering. The paper covered four main branches of engineering. However, this field comprises far more spheres of human activity. Even looking at the mentioned branches, one can say that things are going better. Engineering, as a sphere related to developing and creation of something new, should implement modern trends. Since the most widespread modern tendency is energy saving, using renewable sources of energy and eco-friendliness, engineering has to implement these tendencies. In the next 15-20 years, I see engineering development clearly – it is going to be modern, low power consuming and the pioneering field in using energy-saving techniques.

On the other side, the main problem in the field is that new technologies are far more expensive than conventional ones. This is a great roadblock for further development. In addition, due to high bureaucracy and economic reasons the development may be slowed down. However, as the demand grows and technology spreads, it usually becomes cheaper. Nevertheless, looking at modern condition of conventional energy use it becomes obvious that it is not suitable for the growing demand. In future, people will run out of conventional energy sources and alternative means of power would become the only way to support mankind. Therefore, there is a great point in turning to these energy sources.