Sunday, July 21, 2019

Efficient Technology To Save Energy In Construction Environmental Sciences Essay

Efficient Technology To Save Energy In Construction Environmental Sciences Essay The literature review has numerous objectives. These objectives exist to assist the researcher dealing with the relevant problem to give meaning to the findings. The more information the researcher can collect, the more the researcher can undertake the relevant research problem stated (Leedy, 2005:65). This chapter will discuss what importance green energy has on the saving of natural resources and energy in South Africa. The result of previous studies on the related research problem is analysed and discussed. 2.2 The introduction of Green Energy to the environment Green Construction has only been in use since the 1970s, making it a relatively new concept. Green Building is not just for environmentalists, but for all people who like to breathe clean air (Montoya, 2010). Gibberd (2009) stated that Green Energy in South Africa is still a relatively new concept, although awareness has dramatically increased in the last two years (2007-8) due to: Electricity shortages More local awareness of potential water shortages Rising global awareness of climate change issues Demand from international organisations operating in South Africa. Buildings consume a major amount of the worlds energy. Most of the structures that are built and inhabited are highly inefficient in their energy use. For example; Inefficient heating and cooling systems and poorly designed lighting systems can increase a buildings energy use significantly. Energy generation is one of the greatest contributors to global pollution. Inefficient energy use also affects a buildings long-term operational cost (Montoya, 2010). Kibert (1994) explain sustainable construction as creating the environment healthy by utilizing resource efficient, ecologically foundation principles. This highlights the acceptance of construction and design techniques that are resource efficient and that will not compromise the associated health of the residents, builders, public, future generations or the health of the environment. The substantial negative environmental impacts of buildings have lead to the emerging concept of green buildings which are designed to be energy and water efficient, use non hazardous materials and provide healthy productive environments (Kilbert, 1994). 2.3 Discussing the different objectives in the form of a literature review, based on previous research 2.3.1 Different types of Green Energy Technology to be utilize 2.3.1.1 Wind energy Wind energy uses the power of the wind to produce electricity. A wind turbine the modern equivalent of the windmill uses the winds energy to generate electricity. It is the biggest work producer and is required strong winds. Wind turbines are large and, the area below the turbine can be use for farming due to the reason that it use small space, it may be unattractive looking equipment. Wind turbines also make a noise to operate (Hick, 2002). Wind power is possibly the technology with the best potential to provide large amounts of clean, renewable energy in the decades to come. Wind turbines are already a cost-competitive source of electricity in a number of parts of the country. Wind power, like some other forms of renewable energy, is an irregular resource. Wind turbines can only generate electricity when the wind is blowing (Sargent, 2006). Wind energy systems fairly low costs have also helped in decreasing our trust on the traditional natural resources. Use of wind power plants is environmentally friendly, and helps to keep the general environment clean with continuously supply of clean, inexpensive energy, that can be transmitted to many homes and buildings (Habjance, 2010). By using wind energy instead of conventional one based on natural resources, you will be able to not only decrease your electricity bills but youll also help our planet recover from pollution and climate change problem (Habjance, 2010). 2.3.1.2 Hydropower Hydropower use water to produce energy. This is the most constant of green energy sources. Disadvantages that occur are it have an effect on the ecology and lead to downstream problems. The decomposition of soil and vegetation along the riverbed can cause the build-up of methane. Methane is a causal gas to greenhouse effect (Perry, 2002). Hydropower is the cheapest way to generate electricity today. No other energy source, renewable or non-renewable, can match it. Producing electricity from hydropower is cheap because, once a dam has been built and the equipment installed, the energy source which is flowing water is free (McGraw, 2009). Hydropower enjoys several advantages over most resources of electricity power, including reliability, low operating cost, doesnt produce waste products, acid rain or greenhouse gases (Draper, 2003). A dam on the river, which store water in a reservoir, is the most common type of hydropower plant used. Water thats being released from the reservoir flows through a turbine, which leads it to spin, which turn on a generator to generate electricity. Hydroelectric power doesnt require a large dam to operate. Hydropower plants can use a water canal to channel water through a turbine (Konrad, 2010). Hydropower doesnt pollute the air but construction and work of the dams can affect natural water systems and also affect wildlife and fish population Hydropower today provides about 20 % of the worlds electricity and is the main energy source for more than 30 countries (Eastley, 2008). 2.3.1.3 Solar energy Solar Energy uses the sun to generate energy. It is beneficial because the method can be installed in an existing building and it does not use space. The area which the solar energy collectors utilize is large, which lead to more materials used. Solar radiation is controlled by geography, which is dependent on daytime. Solar energy technology is limited to non-cloudy days and daytime hours (Hick, 2002). Solar energy like the other renewable energies available is safe and also environmentally friendly. No emissions occur, due to the fact that the sun is the fuel, unlike coal-powered stations (Draper, 2003). Solar power is electricity generated from the levels of natural energy contained within the suns rays. The sun shines down on our earth, providing solar energy to the surface. This solar energy is usually recognized as solar radiation and contains a large amount of energy we are able to harness (Eastley, 2008). Solar power is the most common form of renewable energy in each region, used by over half (52%) of industry professionals today and expected to grow to 76% in the next five years. The most dramatic growth is expected in wind power use (57% expected in 2013, up from 20% today), followed closely by geothermal power (expected to double from 22% today to 45% in 2013) (McGraw, 2009). Solar energy technologies use the energy and light of the sun to generate heat, cooling, electricity, industry and businesses. A large variety of different technologies have been developed that can take advantage of solar energy (Anselmo, 2003). When solar power technology is in position to transfer it to valuable energy, the fuel is free and will never be affected by the energy market. It symbolize a clean alternative to the fossil fuels which currently pollute the air and water, contribute to global warming and threaten public health. Given the great quantity of solar energy, this will play an important role in the future (Anselmo, 2003). 2.3.1.4 Geothermal Energy Geothermal energy is heat inside the Earth. This heat can be as steam or hot water and can be use to generate electricity and heat buildings. The environmental impact of geothermal energy depends on how it will be utilized (Draper, 2003). Cameron (2005) stated that geothermal energy is a very efficient and powerful manner to obtain renewable energy from earth through natural route. This can be executed on small scale to provide heat for residential unit, or on a large scale for energy production through a geothermal power plant. Geothermal energy is a renewable energy source because the heat is constantly generate inside the Earth. Geothermal energy is used around the world to heat homes and to generate electricity by excavating deep holes and pumping steam or hot water to the surface. The use of stable temperatures near the surface of the Earth can heat and cool buildings (Eastley, 2007). Energy in the ground is actually stored energy from the sun. At six feet below the surface, the earths temperature is a constant 10-15Â °C (40-60Â °F) all year round. This latent energy is a steady heat source, even in the coldest winter (Smith, 2002). The pressure of the thermal energy increases with depth, the temperature of the Earth increases when getting to centre. The global average for Earths geothermal gradient is in the region of 30Â °C/km (Smith, 2002). 2.3.1.5 Biomass Energy Biomass is the oldest fuel known to humanity and is still widely used in developing countries, where it accounts for about 35% of primary energy consumption. Biogas can be utilized for electricity production on sewage plants and used conveniently for heating, cooking, space-heating and water heating (Montoya, 2010). Biomass is a clean renewable energy resource produced from waste of natural and human activities. Biomass excludes organic material, which in geological processes transform into material such as coal and petroleum (Draper, 2003). Biomass energy offers an alternative source of energy. The use is environmentally friendly due to the fact that the biological mass is reduced, recycled and the used again (Anselmo, 2003) 2.4 The availability of Green Energy Technology and Resources in South Africa South African designers are aware of Green designing and it is one of the most compelling factors when designing a building, but African professionals have completely different design considerations that instigate constraints in attaining green architecture (Cadrecha, 1997). South Africa has a great quantity of resources for wind, and has large space of open land and infrastructure, which have the potential to become a wind powerhouse. A single province alone, wind has the potential to produce 10 times the national wind energy estimates. Even though is highly favoured by green lobbyists, wind power has problems to conquer. It costs can be up to three to four times as more than a coal-generated power (Lawrence, 2006). Eskom calculated that the reasonable working wind resource on the coasts is approximately 1 000 megawatts. Wind farms can be built fairly quickly; will take a year to build one that will provide 100 megawatts (Gcabashe, 2004). Nations such as Denmark have shown that it is possible to obtain as much as 20 percent of their electricity supplies from the wind. While wind industry analysts suggest it is possible to have up to 40 percent wind power as part of a smoothly functioning electricity grid (Sargent, 2006). According to Eskom (2008) it will use its proposed $3.75-billion World Bank loan to roll out lower carbon technologies, such as important solar-thermal and wind power, as well as to fund construction of the Medupi coal-fired power station. Lemercier (2009) noted that a factor is the lack of ability to move past its coal dependability, and the funding from the government to Eskom and its coal objective. A starting point for this would be dealing with the issues of renewable energy and putting a stop to the monopoly of Eskom. South Africa is in front between the rests of the African countries when it comes to incorporate alternative/renewable energy sources. Wind, biofuels, solar, and potential wave energy are among South Africas growing awareness (Lemercier, 2009). Njobeni (2010) stated that green building is becoming the standard between hotel chains and large companies and while a 34% decrease in carbon emissions is very motivated, if any country can do it, so can South Africa. According to South Africa Wind Energy Statistics 2004, there are approximately 30 000 windmills in our country. Wind energy is the fastest developing of all renewable energy and one of the inexpensive renewable energy sources available. It can be soon the cheapest way to generate energy on large scale, but can be more costly than other energy sources. The benefits for ecology make it a very acceptable energy source, in areas with appropriate climate conditions (Draper, 2006). South Africa has good wind potential, particularly at the coastal areas of Eastern and Western Cape. The Klipheuwel wind farm is operating close to Cape Town and the Darling wind farm is likely to operate early 2007 (Gcabashe, 2004). (Draper, 2009) stated that South Africa has a substantial growth area for green energy. The need to meet growing electricity demand, combined with the need to reduce carbon emissions in response to the pressures of climate change, means there is great potential to use the countrys abundant of wind and solar energy resources. South Africa has fair potential for hydroelectric, and the establishment of small hydroelectric projects can help provide a sustainable future energy contribution. There are 6 000 to 8 000 potential sites in South Africa suitable for small hydropower-utilization under 100 megawatts (Lemercier, 2009). Steiner (2008) stated that with the abundant of natural resources, South Africa is consider as a primary candidate for increased utilization of renewable energy. The country is dependent on coal burning for power generation, although having a number of hydroelectric plants and only one nuclear power station. Every energy source, whether its green or otherwise, it requires energy. The generation of this energy will create pollution during its production. Green energies impact is minimal (Cameron, 2004). Wong (2006) stated that new energy sources are available for almost every one and it is free to use. Energy sources like the wind, water and sunshine are for everybody and are free to use. Technology is just required to convert these sources in to useful energy. The present installed hydropower in South Africa reached a capacity of 2,267 MW, generating on average annually about 4,368 GWh. This represents about 2, 3% of the total energy output in South Africa (Klunne, 2009). Khumalo (2008) stated that the largest hydroelectric power plant, Drakensberg Pumped Storage Facility, in South Africa is 1 000 megawatt, part of a larger design of water management that delivers water from the Tugela River to the Vaal watershed. Earth prevents a large quantity of energy radiated by the sun. After absorption and reflection in the earths atmosphere, the total radiation reaching the land area is roughly 1 kilowatt per square meter at noon on a sunny day. Direct solar energy can heat water or buildings and generate electricity in solar cells (Cameron, 2005). Areas in South Africa average 2Â  500 hours of sunshine per year, and the average solar radiation levels range between 4.5 and 6.5kWh/m2 in one day. The annual 24-hour global solar radiation average is about 220 W/m2, when compared to the USA with about 150 W/m2, and Europe and the United Kingdom about 100 W/m2. South Africas resource is thus one of the highest in the world (Cameron, 2005). McGraw (2004) stated that the utilization of solar energy is the most available resource in South Africa. It provides a number of potential uses and the solar-equipment industry is developing. Biomass is renewable, the making of waste products will always be occurring, plants and trees die and the cycle will always continue. This ensures that sources will always contribute to biomass (Cameron, 2005). South Africas Bio-energy project is established in Durban. The Ethekwini (Greater Durban) Municipality use gas from three of its landfills to produce electricity to the city. New plant such as PetroSA, Mosselbay is also in operations (van Heerden, 2006). Sargent (2006) estimates that there is potentially 1.26 billion GJ of energy available annually from biomass residues. Biomass energy could thus theoretically provide 50 % of the national demand. Several types of alternative energy are easily available, commercially feasible and practically applicable (van Heerden, 2006). 2.5 The importance of Green Energy in modern environment Renewable resources have a lack of ability to make carbon-based warming and polluting the air and water. The cost of the resources is not always cost-effective, however if the environmental costs of utilizing fossil fuels are accounted for, renewable energy is the greatest practice to deal with. The indirect savings on health and there are no harmful emissions (Leipoldt, 2001). Renewable energy does not reduce natural resources nor does it destroy the environment. Renewable energy technologies tap into natural cycles and methods, convert the available and current energy into usable forms, the saving of energy and natural resources is crucial in our country as well as planet (Muller, 2002). Previously studies shown that the concern and awareness of the public about global warming is not only a purpose of logical information. Both sociological and psychological factors have an influence on the enthusiasm of the general public to accept the reality of global warming, and to support the climate policies (Sandvik, 2008). Even though renewable energy sources have energy security characteristic and positive environmental, most renewable technologies are not capable to compete economically with fossil fuels through the projection time outside some of the regions (Battle, 2010). Winkler (2003) invested that renewable energy and energy efficiency is important to reduce the negative economic, social and environmental impacts of energy production and consumption in South Africa. Renewable energy contributes relatively little to primary energy and even less to the consumption of commercial energy. Winkler (2003) stated that the Ethekwini project illuminate 9 000 homes which necessitate 10 Megawatts of electricity to be produced. Amount up to 80 000 tons of coal could be saved annually, which would be burnt and contribute to the greenhouse gasses currently present in the atmosphere. Biomass energy brings abundant environmental benefits; reduce water and air pollution, reducing erosion and increasing the soil quality, and improving wildlife habitat (McGraw, 2005). Renewable energy sources are wonderful options because it is limitless. It wont run out, as fossil fuels will eventually run out on which electricity currently depends upon. Also another great benefit from using renewable energy is that many of them do not pollute our air and water they way burning fossil fuels does (Hick, 2007). Even in view of the scarcity of the supply if fossil fuels as a source of power, it makes important sense to be actively considering using alternative forms of energy (Anaya, 2006). South Africa depends a great deal on fossil fuels and nuclear power stations to generate its electricity supply. The result is a system that lacks diversity and security, threatens the health of people, prevent future generations from clean air, clean water and energy independence and jeopardize the constancy of planets climate, (Winkler, 2003). According to Smith (2002) renewable energy resources is capable of meeting an important proportion of South Africans energy needs, and can help ease the problems of power shortages, power shutdowns and saving on natural resources. A commitment to renewable energy development can: Increase economic development and creates new family wage jobs Create competition to control and prevent fossil fuel prices to increase Protect the economy from fossil fuel price increases and supply shortages or disruptions Reduce a growing reliance on imported electricity ad fuel Protect the natural resources for the future generations Most renewable energy finances are used on workmanship and materials to construct and maintain the facilities, rather than on expensive energy imports. Renewable energy investments are generally in the nation. Meaning that, energy money stays home and creates jobs and fuels the local economies (Cadrecha, 2009). Estimates show that natural resources can only supply our energy demands for another fifthly to seventy years. With the discovery of alternative energy sources, the world has start focusing on renewable energy sources as the answer. There are many disadvantages and advantages to this (Hick, 2002). 2.5.1 Advantages Renewable energy sources have environmental, health, economic and cost advantages over fossil fuels. Environmental No contribution to global warming No polluting emissions We can use it repeatedly without depleting it Health Healthier and safer indoor and outdoor surroundings Personal pleasure Renewable energy sources are vital to sustainable human life on earth Economic and Cost Low cost applications when counting all costs Enhanced asset value and profits Reduced operation costs Require less maintenance on their plants Fit into existing buildings and it does not affect land use 2.5.2 Disadvantages Difficult to produce large quantities of electricity required While it is also new technologies, it is costly to initiate Availability of skills and knowledge The economical benefits United States of America will achieve with utilization of Green Energy by 2025 Job Creation 297,000 new jobs from renewable energy expansion Economic Development $263.4 billion in new capital investment $13.5 billion in income to farmers and ranchers, and $11.5 billion in new local tax revenues. Consumer Saving $64.3 billion in lower electricity and natural gas bills by 2025 Climate Solutions Two percent reduction in power plant global warming pollution from todays levels by 2025-the equivalent of taking 45.3 million cars off the road. The impact of green energy technology from the governments point of view Renewable energy have numerous important points to South Africa, it reduces the demand on the electricity network, put a stop to the need for additional power stations to be built to meet demand for power and keeping electricity cost. Lastly it creates opportunities for the introduction of the creation and funding of incentives for projects and products (Eskom, 2009). The considerable negative environmental impacts of buildings have led to the emerging concept of Green Buildings which are designed to be water and energy efficient, use non hazardous materials and provide healthy productive environments, and also reduce their energy consumption to less than half of what a conventional building uses (CIDB, 2009). South Africa generate approximately 34 000 megawatts of electricity to supply the present requirement, and this figure is increasing annually. The greatest economical method available is to utilize the natural resources supplies of low-quality coal (Eskom, 2009). AGAMA (2003) stated that a study evaluated the role that renewable energy could play in job creation. The projected electricity demand for the year 2020 is expected to be 267 TWh, increasing from the 2000 electricity generation figure of 181 573 GWh. If an additional 62 TWh is to be generated by renewable energy technologies and coal capacity, around 52 000 jobs will be created, which have a good impact on the jobless in South Africa. 2.7 The cost implication involved with Green Energy South Africa lagged behind in the implementation of solar water heating mainly due to the high costs involved. A typical residential solar water heating system reduces the need for conventional water heating by about two-fifths (Gibberd, 2008). Hick (2002) stated that one of the causes there are not a large amount of solar energy technology systems and installations is by reason the cost involved, as the cost of fossil fuels stays lower than the first investment towards the present availability of solar panels, there will not be a large shift towards solar electricity construction. Green energy technologies are a costly action and can be argue if the investments are meaningful. If a person feels that the technology investment is worth it, the technology is available to be used. For corporation, individual and housing there are remarkable technologies on the market. Businesses that concentrate in these energy sources are advancing and new concepts are being develop that are better (Wong, 2008). Wind and solar are intermittent technologies which can only be utilize if the resources are available. When built, the costs of operating wind or solar technologies when there source is available is generally much less than the cost of operating conventional renewable generation. But high construction costs can make the total cost to build and operate renewable generators higher than those for conventional power plants (Cassidy, 2010). What is the cost per kWh for wind/solar/geothermal? Can be difficult to answer (Konrad, 2009). Some of these revenues have been used for public expenses, but usually on social goods such as national electrification rather than environmental benefits. The challenge for renewable electricity is that these factors have enabled Eskom to keep tariffs low Cassidy, 2008). The National Energy Regulator of SA last year announced SAs renewable energy feed-in tariffs, which the renewable industry said were attractive enough to stimulate investment (Njobeni, 2010). The higher the demand for electricity increase, the more power stations are compulsory. This will lead to large requirement of capital in turn, it will increase the consumer energy costs (van Heerden, 2010). With government encouragement to utilize wind and solar technologies, their costs have come down and are now in the same league as the increased costs of fossil fuel technologies due to likely carbon emission charges on electricity generation from them (Cassidy, 2005). Of course it is expensive. Not many energy sources can compete with fossil fuels on a purely economic basis. But we cant go on like this forever. Either we manage to make the difficult decisions required to move away from fossil fuels, or we will simply find ourselves at the mercy of events outside our control. My preference is for a planned transition, even if it is difficult (Rapier, 2004). Alternative energy in all its forms is not so far competitive on the price front for everyday users. It will work with help from the government subsidies or good corporate of the nation who will pay a premium to market them as being green (Muller 2008). Muller (2008) stated solar is more expensive than any other resources, but wind is in fact cheaper than a new gas plant or a new nuke, although it is not cheaper than a coal plant. According to Hansen (2009) its too expensive. At the moment fossil fuels are the cheapest form of energy. Kornevall (2007) stated that solar panels are so expensive at present that it is about 10 times more than fossil fuels when comparing it in terms of cost per unit of energy output which only wealthy people can afford to install them. When utilize the alternative energy technology is required to convert the energy sources into forms that can be used. This technology can be costly, but will save money in the future. Several governments are endorsing it, can profit from tax credits and other benefits. Therefore, at the best price the investment can be valuable for all parties (Young, 2008). Paul (2009) stated energy is becoming very costly and by utilizing it, it has negative side effects, for which the price is paying for. To avoid a condition where only the wealth people can effort it, the course should be change and different route should be taking into account. Although renewable energy is usually more costly than conventionally produced supplies, alternative power reduce pollution and to preserve fossil fuel (Waker, 2004). The price of electricity in South Africa is very low compared to other countries. Numerous countries have also embarked upon large build plans and programs and the gap between South Africa and the rest of the world is expanding (Eskom, 2009). 2.8 The barrier to installation, implementation and utilizing of Green Energy Technology According to Layham (2010) the following factors play a role in the prevention of Implementing Green Construction, in other words these are hindrances which needs to be dealt with in order for Green Construction to be implemented: Construction Products Characteristics of construction products should be optimized towards improving their sustainability performance, with considering the variables such as climate, culture, advancement of industrial development, and others. Manufacturing of Construction components can contribute to improving sustainable performance in various ways, ant typically they are 1) reducing the embodied energy of the components, 2) To alleviate the emissions from producing construction components CIDB (2009) stated, while Green Construction is not yet standard practice, and a relatively new concept, the need for Green Construction has drastically increased from 2007-2008 due to electricity shortages, water shortages, rising global awareness of climate change issues and the demand for international organisations operating in South Africa. Government agency (2009) stated that there is no need to tender but tariff will be required, and other says one must bid to generate renewable energy. This lends itself to investor ambiguity and confusion, which is a barrier to utilize the technology. According to Morris (2008) the entity that has control over the planning process can also influence the degree to which the renewable energy market can be opened, hence the fear that Eskom, if it develops the national plan, will once again dictate. Renewable energy market players believe that the market for renewable energy has major room for expansion, the renewable energy target could be expanded up to 15% rather than the currently predict 4% penetration, which takes us to the bottom of why who is tasked with the development of South Africas future energy plan is such a politically sensitive issue (Fakir, 2009). According to Munnik, AGAMA (2003) there is significant barriers to the further implementation of renewable energy that need to be addressed. The key issues include the following: Many renewable energy technologies remain expensive, on account of higher capital costs, compared to conventional energy supplies for bulk energy supply to cities and large industries. Implementation of renewable energy technologies needs significant initial investment and may need support for relatively long periods before reaching profitability. There is a lack of consumer awareness on benefits and opportunities of renewable energy. Financial, legal, regulatory and organisational barriers need to be overcome in order to implement renewable energy technologies. 2.9 Conclusion The purpose of this chapter was to outline the importance of Green Energy

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