This research provides guidance as to the most successful style of renewable energy in replacing the current dominant fossil fuels in the future. This success is based on a number of key variables, not least the implications of cost, management and longevity that are intertwined with developing, installing and running a renewable energy source. The case-study focused on the four main types of renewable energy, solar power, wind power, biomass energy and geothermal energy and came to some interesting conclusions.
A mixture of qualitative and quantitative research was used, with the majority of the findings coming from the qualitative research. However, the quantitative research was in the form of two case studies highlighting the effectiveness of two types of renewable energy in certain household situations and how the energy can replace that of traditional fossil fuels.
The findings show that while no one particular renewable energy type gained a majority backing from the research, knowledge about these types of energy is still perhaps too limited for any person to make a correct and informed choice as to the development of renewable energy. The qualitative research indicated that there are many strengths and weaknesses to each type of energy, while the quantitative research stressed that in certain situations renewable can be very effective. Another key finding of the literature was that general knowledge and understanding of renewable energy is not at an acceptable level in terms of the general public and leads to the recommendation of increased awareness.
Aims and Objectives
This section is designed to provide a detailed overview of the research aims and objectives of the present dissertation and the research questions that the study will try to answer in as comprehensive a manner as possible within time and resource constraints.
The aim of this study is to establish the possible options for renewable energy available in the United Kingdom for future use. This will be conducted through a comparative analysis of the four main types of renewable energy currently available, solar energy, wind, biomass and geothermal energy. The main aim of the research is to:
o Identify successful alternatives to the non-renewable energies in the United Kingdom
In order to achieve this, a number of objectives will need to be met. The aim of the research is to be able to conclude with clarity, the most attractive option or options available to the United Kingdom and its government in terms of renewable energy, for the current day and moreover, into the future. The uncertain prospect of the traditional non-renewable energies, coal, oil and natural gas, have meant that renewable energies have had to be developed with the aim that in the future, these newer, more environmentally friendly options will gradually take over the burden of energy supply in the United Kingdom.
Based on the research aim outlined in the previous subsection, the research objectives that the present study will seek to achieve are as listed below:
o To undertake an investigation into the four main sources of renewable energy; these include Solar Energy, Wind, Biomass and Geothermal energy.
o To gain an understanding of the history and development of these energies is needed to fully understand the extent to which the United Kingdom can rely on them in the future.
o An analysis of the benefits and disadvantages of each particular type of renewable energy
o To explore how well the government is backing renewable energy with incentives
o To examine the financial implications – to gain an insight to how much renewable energy will cost in installation, what grants are available?
o To examine design implications – installation of renewable sources, aesthetic, dimensional requirements.
There are particular research questions that will need to be addressed when attempting to analyse possible future energy alternatives. These include:
* How significant is the extent of cost when attempting to replace non-renewable energies with the more environmentally friendly types?
* How far does the government wish to develop all four types of energy? Do they have a particular idea as the market share that each one should ideally hold on providing energy to the United Kingdom?
* What can history tell the research about the likelihood that these renewable energy methods will succeed over a longer period?
* Can (and will) these renewable energies ever fully replace the non-renewable energies that the United Kingdom (and globally) has relied heavily and dependently upon since the beginning of the Industrial Revolution?
The research will attempt to address these questions and objectives whilst trying to meet the aim of the entire project; identifying successful long term strategies to replace dwindling non-renewable energy sources with abundant renewable sources while still enabling the United Kingdom to grow and hold its position of relative power and influence on a global scale.
Ever since the realisation that non-renewable energy sources (coal, oil and natural gas) are exactly as the description suggests, and that the level of these are reducing rapidly due to the global appetite for energy consumption in the continuing race for power, influence and development, it has been apparent that renewable energy sources would have to be developed to enable this global growth to continue. The United Kingdom, whilst overtaken in recent years by countries such as the United States and China in terms of energy consumption, has had a history intertwined with this notion. The Industrial Revolution, beginning in the United Kingdom in the 18th Century, acted as a catalyst for the rapid consumption of a large proportion of the world’s traditional, non-renewable energy sources. This has led to the necessity of developing renewable energy forms to supplement these more traditional energy types, with the aim to take over the burden of energy supply in the future.
Brown (cited in Miller & Spoolman, 2008:211) states that in terms of history, the 19th Century belonged to coal and the 20th Century to oil. However, the 21st Century will belong to the sun, the wind and energy from within the earth. This belief is widely held for a number of reasons and highlights the importance that the development of renewable energy sources has on the current agenda of policy makers and governments on a global scale. However, this will prove to be a difficult challenge. As Sawin (2004) stresses, over the previous decade, the World Bank funding for fossil fuel projects (totalling $26.5 billion) far exceeded that for renewable energy (Sawin, 2004:13). It is this type of obstacle that can make the development and mainstreaming of renewable energy difficult to implement and is why it is so crucial to research this issue, highlight the financial costs of renewable energy as a long term successor to the fossil fuels and increase public knowledge of renewable energies and their benefits. The renewable energy options are possibly limited to four main types. Whilst many various options have been and are being developed by researchers and scientists, only four are currently at a stage where they could develop enough energy to be able to supplement and then eventually succeed non-renewable energy. These are highlighted as solar energy, wind power, biomass and geothermal energy (Tiwari & Ghosal, 2005:17). These four types of energy will therefore form the focus of the research with each particular strand of energy being investigated to establish whether it is feasible that any one (or perhaps a combination) of these energies can ever be relied upon to replace fossil fuels. This is the long term aim of renewable energy, whilst at the current time, they are still on the periphery in terms of usage when compared to non-renewable energy forms.
The research will identify strengths and weaknesses of each of the four types of energy, particularly focusing on people’s opinions and other variables such as cost, performance and design issues that may gain or lose support depending on the results. The research will be conducted through two different approaches. Firstly, there will be a qualitative analysis of the literature available on each of the four main sources of renewable energy. This coupled with official government information detailing about each type of energy will form the majority of the research. In this manner, the proposed research will be qualitative based. However, the success of the mixed method approach to research, as championed by Maxwell (2005:183), highlights that the research should include quantitative data research as well. This will be conducted through two case studies, analysing the effects of two of the renewable energy sources on a small scale. These will be focused around particular individuals’ attempts to use a form of renewable energy to replace more traditional fossil fuel energy in their home. The quantitative data achieved by these two samples will provide evidence as the success of the renewable energy type in replacing more established non-renewable energy in an everyday life situation. This will enable the research to identify key areas that surround the debate over renewable energy sources and the suitability of each of the four main types in their possible future role as the majority providers of energy to the United Kingdom.
1.1: Solar Energy
Solar energy is perhaps the most prominent of all the renewable energy sources currently available. Solar energy has existed in many forms for thousands of years (Craddock, 2008:28). He stresses that early users of solar energy include the Romans who used the suns’ rays to heat their rooms and designed south facing windows to make use of the heat provided by the sun. In the modern era, technology has developed rapidly and solar energy is now seen as much technical and efficient than ever before. The literature review will analyse solar energy and emphasise the strengths and weaknesses of the energy as a possible candidate for large scale usage on a national level.
As Figure 1 highlights, when the sun’s rays shine upon a solar panel, the effect converts the light energy to electrical energy. In this instance, the power from the solar panel is directly proportional to the amount of light shining on it, so if the light from the sun is three times as bright on a particular day than the previous day, then you will receive three times the power. (Stubbs, 2008:4) The development of solar energy has occurred due to the understanding that our current way of life cannot continue if we remain economically dependent on fossil fuels. A champion of solar energy, Scheer (2004) supports the theory that it is imperative that we make comprehensive use of solar energy, not just to augment fossil fuels but to replace them before they either run out or critically damage the world through pollution and dangerous emission levels (Scheer, 2004:4). There are two main formats that solar energy takes. These are passive and active formats (Craddock, 2008). A passive solar energy system uses the sunrays directly to heat water or gas. The active system converts the sun’s energy into electrical energy by using a photovoltaic semiconductor material called solar cell (El-Sharkawi, 2005:89). The researcher also provides evidence that solar power can be relatively low in terms of its efficiency stating that the electrical power output of the solar panel, arrived at by multiplying the solar power input by the efficiency of the panel (Figure 2), can often produce a low amount of energy.
The energy produced in the equation above is only high enough to power two light bulbs. This can be countered by increasing the size of the panel and the efficiency of the panel. These two changes will increase the output (El-Sharkawi, 2005:89). Developments made recently should, according to Jones (2003:48), allow solar cells to operate more efficiently. The recent innovation of solar concentrators is used in solar thermal technology to generate heat to power turbines. With solar concentration technology, mirrors or lenses focus light onto specifically designed cells. The older versions of solar cells have solid absorbing layers that require clear skies and direct sunlight to produce energy. However, new solar concentrators follow the sun’s path through the sky during the day allowing a better chance at finding direct sunlight. This highlights that solar power is increasing in efficiency and from a relatively un-technical beginning, solar power is now a real possibility at providing alternative power to fossil fuels in the future.
Wind power is perhaps the most striking of all of the recent developments in renewable energy. The wind turbines that adorn high peaks across the country are constant reminders of the attempts by the government and industry to develop renewable energy. Wind power is generated through the utilisation of large scale convective currents that carry heat from lower latitudes to more northern destinations. These create rivers of air that are used by newly developed wind turbines to generate power. (Figure 3)
Winds are strongest at high peaks and specifically more frequent and at their strongest along the shores of lakes, seas and oceans, restricting the placement of wind turbines to coastal regions in many parts of the world (Gipe, 2004:24) As Figure 4 highlights, the power of wind can be increased to almost two hundred percent of its normal speed as it reaches the crest of a peak, thus ensuring the positioning of the wind turbines. These have led to many criticisms of the aesthetics of the turbines, given that they are large and seen as imposing by some onlookers. The wind turbines can produce a large volume of energy but are dependent on nature and days of unusually low wind speed can reduce the effectiveness of the turbines remarkably.
When the wind speed is above the level needed to produce the maximum efficiency, no power losses are achieved in the system. It is only when the wind speed drops below the necessary level that the efficiency of the wind turbine drops (Hau, 2006:489). There are a number of strengths and weaknesses of wind power and these will be assessed in the literature review. However, the UK has increased its share of the wind turbine market recently (at an average rate of 35% per annum) in its attempts to increase the percentage of which all electricity generated will come from renewable sources by 2020 (This has been set at 20% : Government White Paper, 2003).
There are various types of wind turbines, in different shapes and sizes, developed to harness the wind power at a particular geographical location. The main two versions of the modern wind turbine are based around the axis. The two different types are the horizontal axis and the vertical axis. The horizontal axis (Figure 5 above) is the most commonly seen in the United Kingdom and is popular due to the high efficiency rating. The higher the tall tower base, the higher the wind speed and the more output that can be created. This is why the horizontal axis is the most popular.
However, this is also one of the disadvantages with complaints arising about the sight of these wind turbines on the horizon from many locals when they are installed. Vertical axis wind turbines (Figure 6) are less common in the United Kingdom. These vertical axis turbines are less common due to the fact that they are generally less efficient, because of the nature of its rotation and the stress on the blades. This leads to frequent replacements and therefore a higher cost. They are, however, less tall than horixontal axis wind turbines and therefore less of a distraction on the horizon for those that are angered by the horizontal axis types.
Biomass energy is defined as any solid, liquid or gaseous fuel source derived from recently dead biological material. This is opposed to fossil fuels that come from long dead biological material. Biomass constitutes the largest non-hydroelectric renewable source of primary energy in the United States and its presence is growing rapidly in the United Kingdom (Turner & Doty, 2009:443). This is highlighted by Chiras (2006:21) who stresses that many countries are now turning to biomass as an alternative fuel source due to its relative ease in creating energy and the low cost involved.
Biomass includes a wide assortment of solid fuels, such as wood, and liquid fuels such as ethanol derived from corn and biodiesel, a liquid fuel made from vegetable oils. The wide variety of forms that biomass can take can be found in figure 7. Biomass is remarkably popular as an energy source, as stated previously due to the low cost and relative ease at obtaining the materials needed for conversion.
The three main conversion types are anaerobic digestion, fermentation to alcohol and the thermal process which produces a range of fuels and by-products including methane, methanol and ethanol that can produce heat, power and light, as well as fertilizers and fibres that can be used to produce food, textiles and plastics. (Figure 8)
This range of products and power that it can produce make it very flexible and attractive to those who support the development of renewable energy. However, one key advocate of biomass energy states that currently most use of biomass energy is not clean or sustainable. The pollution caused by burning wood, manure and agricultural waste is causing severe health problems. It is also true that some energy crops have a bigger energy and environmental cost than they return. Thomas (2007:44) indicates that if biomass is to be a vital part of the future energy mix then there needs to be methods developed to process and use it in sustainable way over a long period of time.
Biomass energy has accounted for over thirty percent of the United Kingdom electricity generation from various renewable energy types over the past five years. This amount is only second to that of hydro power (Institute of Physics Report, 2010). Although the total amount generated by renewable energy is still relatively small compared to that of traditional fossil fuels, it highlights that if biomass can be developed on a larger more industrial scale, and if more environmentally friendly processes can be created, then the usage of biomass technology may increase dramatically in the near future. Support within the United Kingdom exists for the development of the biomass energy industry. A recent report (European Wind Energy Association, 2009:524) highlights that the United Kingdom government has developed grant schemes (funds reserved from the New Opportunities Fund) for investments in energy crops and biomass power generation of at least £33 million over three years. This will hopefully enable the biomass industry to develop cleaner, more sustainable methods of creating biomass energy that can be used on a much larger scale.
Geothermal energy is identified as power extracted from heat stored in the earth. It has a long history of use, from simple ways such as bathing to the modern use; that of generating electricity. In recent years, geothermal power has developed but still only supplies around 0.5% of the global electricity. Geothermal power is identified as cost effective, reliable, sustainable and environmentally friendly. However there are setbacks in the development of the energy. The main negative aspect of geothermal energy is that it is has been historically limited to regions that are close to or on tectonic plate boundaries (Craddock, 1998) Geothermal power works through a relatively simple process, exploiting the heat of the earth and transforming it into electricity. Figure 9 highlights how this process occurs. Capehart (2007) underlines the abundance of geothermal power and states that the resource base for the power can be drawn from shallow ground to hot water and rock several miles below the Earth’s surface to even further down, to molten rock known as magma (Capehart, 2007:377).
There are three types of geothermal power plants operating in the world today. These are dry steam plants, flash steam plants and binary cycle plants. Dry steam plants directly use geothermal steam to turn turbines. Flash steam plants pull deep, high pressure hot water into lower pressure tanks and use the resulting flashed steam to drive the turbines.
Binary cycle plants pass moderately hot geothermal water by a secondary fluid to flash to vapour and then this vapour then drives the turbines (Capehart, 2007:337). Geothermal energy is seen as very reliable in that it has an average system availability of 90-95%. This is far higher than other sources of renewable energy. There is however a negative aspect in the aesthetics of the geothermal power plants, with many scholars highlighting the unattractive nature of the plants (figure 10) as well as negative public opinion on this matter (Saunders, 2007).
The benefits of geothermal power have been harnessed by countries such as Iceland and the United States for a number of years but only now is the United Kingdom beginning to realise the potential of this renewable energy process. An article by Morris (2009) notes that with the recent development of planning for the United Kingdom’s first geothermal energy plant, the most suited region may be that of Cornwall due to the granite located there lending itself to the process. Morris (2009) emphasises that those behind the Eden scheme believe that Cornwall could provide as much as 10% of the United Kingdom’s electricity for the next one hundred years from geothermal plants. He also identifies other granite basements in the north of England and the north-east of Scotland.
Geothermal power is therefore a currently underdeveloped source of renewable energy in the United Kingdom but has the potential to become a reliable and environmentally friendly source of power over the next few decades. The development of technology should also help to strengthen the support behind geothermal energy, given that at any location on earth, deep down in the core there is the potential energy for geothermal power. If developments can be made the energy to be harnessed away from tectonic plate boundaries, then the power of geothermal energy could perhaps become unrivalled when compared to other renewable energy sources. The literature review will continue this debate as to the strengths and weaknesses of each particular renewable energy resource.
2: Literature Review
This literature review will provide part of the secondary research into the research question posed at the beginning of the work. The aim; to identify successful alternative renewable energy sources to replace that of non-renewable energy sources (fossil fuels) that currently are in demand today. Morgan (2007:9) stresses that while fossil fuels bring enormous benefits to the world, in term of the production of mass energy that has allowed global industry and technology, as well as levels of living to rise rapidly in the last one hundred and fifty years, there a number of negative aspects to non-renewable energy sources. The limited nature of the resources is one, but also the affects that the use of coal, oil and natural gas has on the environment is also a key factor in the need to develop renewable energy sources that are environmentally friendly.
Therefore this literature review will attempt to identify the strengths and weaknesses of the four main renewable energy types; solar, wind, biomass and geothermal and highlight a possible successful candidate or candidates that could take over in producing the large majority of global energy. In this manner, the four main types will need to be analysed in a number of key areas; cost, effectiveness, affect to the environment and aesthetics.
A good overview is provided by Freris & Infield (2008). They highlight that after the United Kingdom government set the target of achieving 20% renewable energy in electricity supply by the year 2020, it became possible to analyse a cost for the proposed energy developments. An analysis completed in 2003 suggested that the extra cost for the development of renewable energy processes would represent an additional 0.3p/kWh on consumer electricity bills. This was focused primarily on wind power, as wind power is expected to contribute the majority of the renewable energy target (Freris & Infield, 2008:215). Other scholars also support the view that wind power is the most expensive of the renewable energy processes. Ackermann (2005:300) acknowledges that the use of wind energy in remote areas is an exceedingly expensive option when trying to harness power from the earth, rather than using non-renewable energy sources.
Quaak, Knoef and Stassen (1999) indicate their preferred method, through cost analysis, is that of Biomass. They state that the initial start up costs are less expensive than wind, solar and geothermal energy plants and also the longevity of the plants as compared to that of wind turbines (that need parts replacing on a regular basis) is a key factor in the cost analysis and that biomass is by far the cheapest of the renewable energy sources currently available (Quaark, Knoef & Stassen, 1999:1).
However, although Walker (2007) identifies that biomass is currently the cheapest form of energy, the scholar also states that solar power could become, over time, the cheapest form of energy. While solar panels are expensive, this is only because of the low number of them. Walker (2007:7) notes that solar cells would become dramatically less expensive if more people bought them, allowing the solar cell companies to reduce prices due to a healthy competition. The simple nature of solar power, combined with a drop in prices could aid the overall cost of the energy source, allowing it to become cheap and competitive with other renewable energy sources. Sass & Duffield support the view of the cheap costs of geothermal energy as opposed to wind, biomass and solar energies. They state that geothermal energy, despite high initial installation and start-up costs, can dramatically lower monthly energy bills and therefore in the long term, or within a few years, the cumulative energy savings equal the extra up-front costs and can become less expensive than other forms of energy. An interesting viewpoint is provided by Orr (2009:23) who indicates that at the current time, none of the existing renewable energies are cost effective and it is why governments across the globe are having to provide grants to develop them. The competitive nature of global society means that only cost effective and profit generating products succeed. Therefore, designers of renewable energy processes need to find ways to lower the costs of purchase for these energies in an attempt to rival cheaper and more established fossil fuel production. It is only in this way that renewable energies can hope to develop rapidly; to the benefit of the Earth.
Effectiveness and reliability
The effectiveness and reliability of an energy source is the most fundamental issue that surrounds its development. An energy that has low levels of effectiveness and low reliability rates will usually never be mass developed, due to the restrictive nature and high costs to gain a substantial yield. Wind power is suggested to have a relatively high effectiveness rating by Spilsbury & Spilsbury (2007). However, other scholars stress that wind power is the least effective of all of the different renewable energies due to the loss of potential power through its design (Petersen, 1999). Other energies such as geothermal, with a 95% availability (Bracaloni et al, 1995) have a far higher efficiency rating. Quaark, Knoef & Stassen (1999:52) also highlight the relative low efficiency rating of biomass energy, stating that conditions at times only allow a 25-35% efficiency rating. Lomborg (2001:134) stresses that the efficiency of solar cells is also around the 20% mark, indicating that geothermal energy is far more efficient that other forms of renewable energy.
One of the key weaknesses of the fossil fuels and their use in energy production today is the negative effects that they have on the environment. The creation of carbon dioxide from the processes needed to create energy from coal, oil and natural gas has acted as a catalyst in lowering climate conditions across the globe. Therefore, one of the main aims for new renewable energy sources is to promote an environmentally friendly strategy. Lomborg (2001) identifies that one of the renewable energy sources being discussed lacks this strategy. Lomborg stresses that biomass energy production gives rise to a slew of pollution problems such as suspended particles, sulphur, nickel, cadmium and lead. This is supported by the Council of Europe (no date) who indicate that the weakness of biomass energy is that it produces relatively large amounts of fine particles and often also other air pollution like polyaromatic hydrocarbons and heavy metals.
Compared to this, the Council stress that wind energy only causes some carbon dioxide and fine particle emissions in the construction phase, whereas solar energy appears to be the most environmentally friendly of the renewable energies. Chiras (2009) identifies this and supports the notion that solar power is perhaps the most environmentally friendly of all of the renewable energies. The construction phase causes less emissions than any other renewable source and the fact that industrial plants (such as that used for biomass and geothermal energy) are not required for solar power means that like wind power, once constructed there is no harm to the environment, with the solar panels soaking up the heat of the sun and transferring this into energy.
The aesthetics of renewable energy is a key factor in gaining support for possible renewable energy sources. Gipe (2004) stresses that wind power often comes under a lot of scrutiny due to the developments of horizontal axis wind turbines that dominant certain landscapes. Gipe indicates that communities are generally against these being developed because of the ugly aesthetical factor. However, he also notes that due to the nature of wind turbines and wind energy, these locations are generally remote and therefore do not affect the majority of people. There is also the development of wind turbines at sea, which could possibly aid the reduction of resentment towards wind turbines. Moreover, Scheer (2007:200) underlines that the rejection of wind power on grounds of aesthetic landscape pollution is treacherous and short-sighted and cites key examples of previous architecture such as skyscrapers as precedents. He also argues that the benefits of wind power far outweigh any argument on aesthetics and therefore feels it is a pointless debate. Chandrasekharam and Bundschuh (2002) feel that there is a similar argument for geothermal and biomass energy plants. The aesthetic factor may often be overriding but the success of creating environmentally friendly (geothermal in particular), renewable energy should outweigh any decision as to the aesthetical impact of these new sources of energy.
A number of key concepts were analysed in this literature review. The review suggests that opinions over renewable energy sources and their potential success rates are divided. While there appears to be agreement in the literature over the importance of developing renewable energy sources due to the fact that fossil fuel supplies are decreasing dramatically and that they have an adverse effect on the environment, there is real debate as to the preferred methods of renewable energy. Perhaps the most important contributing factor may come down to cost, and the literature review suggested that the current cost for all renewable energy forms are too high and will need to be lowered significantly to enable mass production to rival the production of fossil fuels that currently dominate the production of energy, in the United Kingdom and around the globe.
3: Research Methodology
The research to be undertaken for this dissertation will follow a mixed method approach. It will combine qualitative and quantitative data and the subsequent analysis. The findings of the literature review will be coupled with the evidence from two case studies to highlight whether the research aim can be answered with a positive or negative response. The two case studies, each analysing and providing numerical and statistical data, will supply the quantitative data for the research. These case studies are secondary research materials supplied by a reliable source (www.energysavingtrust.org). The two case studies (one of the impact of biomass energy and the other of the impact of wind power replacing traditional fossil fuels) are only completed on a small scale. However the results from these will be combined with that of the literature review to answer the main research question; attempting to identify any successful alternatives to the non-renewable energies in the United Kingdom.
This combination of the two types of research data collection is supported by Thomas (2005) who states that the qualitative approach includes content analysis to identify the factors that affect the success of quantitative questionnaires and therefore a combination of the two should be used when comparing data as quantitative data by itself is not suited to research and analysis (Thomas, 2005:45).
The research methodology of the dissertation will follow a common pattern in modern research. The debate over the success of qualitative versus quantitative data collection seems redundant in the wake of new research recently highlighting the positive effect that can be gained when combining the two. Maxwell (2005) highlights that part of the reason for the disagreement in the qualitative versus quantitative debate is that researchers of the two tend to ask different kinds of questions thereby preventing successful comparisons to exist. Maxwell identifies therefore that a mixed method approach is more successful if planned correctly (Maxwell, 2005:183). In this manner, the literature review will form the basis of the questionnaire and interview questions that will occur concurrently.
The use of the case studies and the literature review will allow a good mix of results from which to draw conclusions. Moreover, as Creswell (2003:64) states, the mixed method approach is successful, especially when the concurrent triangulation strategy is adopted. This strategy attempts to run the qualitative (information gained during the research of the literature review) and quantitative (case study) research methods at the same time. This strategy is perhaps the most common used of all of the mixed method approaches and is successful, if developed appropriately, in confirming (or debating) the arguments set forth by the literature review. Creswell (2003) also confirms that this strategy is advantageous as it is a familiar method to most researchers and can result in well-validated and substantiated findings. It also allows for a shorter data collection period as it is run concurrently rather than sequential, giving more time to complete the data analysis and follow up research if needed (Creswell, 2003:66).
The research on data collection also suggests that as well as the choice of research method, the administering of the research is also central to obtaining results that can be used effectively. Whilst putting aside ethical considerations for one moment, (these will be focused on later) the successful adaption of the literature review for research purposes (a key part of this research and results analysis) is vital. Balnaves and Caputi (2001) suggest that every small detail of the literature review is important. Poor administration of the literature review can lead to an ineffective analysis preventing any potential gains that can be made from it could act as a hindrance rather than effectively aiding the research development (Balnaves & Caputi, 2001:18). In this manner, the research should prove to be successful considering that a combination of research methods are being used (hence the mixed method approach) as well as the detailed planning of the literature review which will help to answer the research question and allow the researcher to meet the objectives and answer the questions laid out at the beginning of this work. Combining qualitative and quantitative data should allow for corroborated results and therefore a strong conclusion to the research.
There are a number of limitations to the research that must be noted here. As with every research work, there are limitations to this study. Research into the renewable energy industry can prove complex at times, especially given the nature of this research and analysing a variety of renewable energy sources rather than focusing on one in particular. However Silverman (2005) summarises that, within the field of qualitative research, limitations are not necessarily a negative aspect of the research. Limitations are often a way of scaling back work from a ideological and ambitious attempt at research to a much more practical and realistic version. The work by Silverman (2005) suggests that limitations are put in place to ensure that research is genuine and not over-reaching. It also provides other scholars to work with reasonable material, narrowed down to be understandable and useful in their particular field. Furthermore, any issues which affect the research, providing that it is noted properly, can be used as a starting point for the next researcher and next study into a certain topic.
The main limitations of the study are the small scale nature of the case studies, only focusing on two individual examples of the use of renewable energy to supplant fossil fuels. Although this is a small sample, it should highlight the savings that can be made by using renewable energy but the size of the sample would need to be considerably larger to highlight mass effectiveness of the systems used. Another limitation can be found in the literature review with the researcher having to choose selectively the content to gain broad and well-rounded opinions of the renewable energy types, highlighting both their strengths and weaknesses. This was particularly difficult given the topical nature of renewable energy and the abundance of literature available on the subject. Furthermore, the nature of the renewable energy industry is such that at its developmental stage, often the literature is being used to convince readers of the benefits of a certain type of renewable energy. This ulterior motive also means that the researcher has to be particularly careful when selecting information to be used.
3.1: Ethical considerations
As Campbell & Groundwater-Smith (2007:2) state, there are a number of ethical considerations that must be taken into account when contemplating practical research. It is pertinent to highlight that perhaps the key aspect of research is that of honesty and integrity. As Thomas (2005) states, an oft-forgotten but central part of any ethical research is the integrity and honesty of the individual conducting the research. Without this, the most well-planned and conducted research is potentially useless. The research will be conducted honestly and with a high level of integrity. All research, both qualitative and quantitative, will be carefully analysed and placed under scrutiny before being used. Furthermore, the results will of course reflect the true nature of the findings rather than tampering with the results to suit the research aim. Moreover, as an important feature of any research, it is imperative that ethical considerations are in mind constantly when conducting the research and therefore these will be considered at every step of the research process, from the literature review and analysis to the investigation into the case studies.
4: Case Studies
The two case studies, one on the effects of biomass and the other on wind power, and how they can possibly displace more conventional and traditional fossil fuels in the home are important in gaining an understanding on the everyday effects for people when using the renewable energies.
4.1: Case Study 1: A biomass case study
Name: Hugh Buchanan
Energy used and form taken: Biomass (woodchip boiler system)
Factors involved: Monetary savings required and environmentally friendly system wanted
Results: 11.500kg CO2/yr carbon savings
This case study focuses on an individual named Hugh Buchanan and his attempts at using biomass energy in the form of a wood chip burning system to replace his usual oil fired heating system. This was necessitated due to the consistent rise in oil but also the environmental factors involved with wood being a carbon neutral alternative energy source to that of oil. It must be stated that part of the costs of the case study will be slightly skewed due to the fact that Hugh Buchanan did not have to purchase the main ingredient, wood, due to the abundance of wood on his property, living in a rural area. The key factors involved in the process were the gathering of enough wood to make the system work, and the purchasing of the wood burning system itself and the further installation that was required.
The installation took two days and it was a relatively simple process. A further boiler had to be laid and plumbed in, meaning an extra fifty metres of piping had to be laid down as the boiler was installed in a shed away from the house.
The results were fairly impressive with the cost of total installation totalled at £7,938, with £2,381 of that amount coming from a grant provided by The Energy Saving Trust. This grant offers homeowners like Hugh up to thirty percent towards the cost of a renewable energy installation system, up to a maximum of £4000. As stated earlier, Hugh was trying to offset the negative environmental factors of his traditional oil fuelled heating system. The estimated carbon savings were put at 11,500kg C02/yr. This amount is not insignificant and highlights that using biomass energy in the home can really make a difference. Unfortunately, the financial savings, the second of Hugh Buchanan’s reasons for adopting the wood burning system strategy were not provided by the case study, a limitation of relying on secondary research.
The full information on the case study can be seen in Appendix A. The information can also be found at: http://www.energysavingtrust.org.uk/Resources/Case-Studies
4.2: Case Study 2: A wind power study
Name: George Jarvis
Energy used and form taken: Wind energy (small scale wind turbine - off-grid)
Factors involved: Diesel generator too loud and costly to run and inefficient.
Results: 2,145 CO2/yr carbon savings
£330/yr saved approximately
This case study focuses on an individual named George Jarvis and his attempts at using wind energy in the form of a small scale wind turbine to replace his diesel run generator on which he relied for all his electricity and heating requirements. This was necessitated due to the fact that the system under the diesel generator was too noisy and costly to run. It was also very inefficient as the generator had to run at full capacity even when the power requirement was very small. The key factors involved in the process were the establishing of the wind turbine in his garden, including finding and installing the turbine which had to be done by two different companies. The installation took place over two periods (due to weather restrictions) and took four days in total to complete.
George Jarvis is pleased with the results so far in that the turbine now provides him with a twenty four hour supply of power that has lower running costs than the previous generator. It is a lot more reliable and has lower running costs. This has enabled George Jarvis to reduce the use of his diesel generator by at least eighty-five percent recently. The cost of total installation totalled at £14,106.75, with £4000 of that amount coming from a grant provided by The Energy Saving Trust. This grant was the maximum available under the scheme. As stated earlier, George was trying to offset the noise, cost and inefficiency of his diesel generator by switching to wind energy. The estimated carbon savings were put at 2,145kg C02/yr. The financial savings, a key part of the decision to switch to wind power, were estimated at £330/yr. This amount was very pleasing to George Jarvis and highlights the success of wind energy and its replacement of an inefficient diesel generator as a small scale example.
The full information on the case study can be seen in Appendix B. The information can also be found at:
The two case studies highlight the importance that renewable energy sources can have at a small scale level, with the focus here on two particular individual households in different areas of the United Kingdom and the success that the switch to renewable energy had. It must be stated that the initial start up costs were fairly high and therefore any financial benefits will have to be witnessed over a longer period, meaning that the two participants would need to remain in their respective houses for a number of years to gain the full benefits of the systems that have been installed.
5: Evaluation and Discussion of findings
In this section, the research aim, questions and objectives will be answered through the analysis of the research. The research focused on two main areas, the qualitative research conducted through the process of the literature review and the quantitative research, conducted primarily through the case study research. The nature of the subject of this work meant that primary research would have been difficult, especially in terms of quantitative data collection due to the expensive nature of the renewable energy industry at the current time and the limited availability of funds that the researcher had to work with. The size of the case studies, limited to two that focus on individuals and singular households also provides a limitation. However, this limitation, as highlighted by the literature review is perhaps in-keeping with the field of renewable energy as a whole at the current time; with limited data due to the overwhelming dominance of fossil fuel related industries supplying power to the United Kingdom and the world.
However, with the limitations noted, there are some important findings highlighted by the two forms of research. The data collected, both qualitatively and quantitatively provide interesting information that can enhance the knowledge of renewable energy sources and their potentials in the United Kingdom. The evaluation will analyse the literature review with the case studies being used to quantify and support several of the arguments in the qualitative research. The overriding question considered through the conducting of the research was whether any possible successful alternatives to the non-renewable energies currently in use today in the United Kingdom could be found. The research conducted, focused mainly on the four of the main types of renewable energy currently available worldwide. These included solar energy, wind energy, biomass energy and lastly geothermal energy. The research highlighted a number of strengths and weaknesses in each of these types and these will be addressed now. It must first be stated however that the research of the literature found a fifth type of energy that would have been focused on, had it been included in the initial research hypothesis. This idea of wave power, highly supported in the literature based around renewable energy can however provide a research question to be conducted at a later date, given the abundance of coastline in the United Kingdom.
The evaluation will focus on each renewable energy type in turn, investigating whether the research findings from this study can successfully identify any of the energy types as successors to coal, oil and natural gas in the United Kingdom, either at the current time or in the future.
The research highlights that solar power has a number of strengths and weaknesses to it, when considering it as a possible successor to fossil fuels. Solar power is a developed technology but it lacks experience when on a large mass production scale. This is due to a number of factors, but most important in all of these is the cost. Even though the government (Appendix C) is offering up to £2000 per KW as a grant for people willing to adapt to solar power, the low take up offer highlights the expensive nature of this form of energy. The research does highlight however that if solar power ever receives enough supporters and customers, then prices would drop significantly. However, in terms of supply and demand, the solar power companies currently have to charge higher prices for their units due to the lack of demand, an inverse of what is needed if solar power is ever to become a mainstream unit of energy. This has led to high start-up costs which immediately detract possible customers from buying solar panels.
The cost factor is the most important when considering solar power. This form of energy has many positive attributes as underscored by the literature. The relatively simple design and unobtrusive nature of the solar cells make it aesthetically pleasing as well as being environmentally friendly in its production of energy; utilising the suns’ rays without harming the environment. However, a more pertinent issue is that of efficiency rating and this is another area in which solar cells are let down. Their efficiency levels are the lowest of the four, given that much energy is lost in the transfer of heat into power. The approximate level of around 20% efficiency poses the problem that may hinder solar power into the future. The larger the surface area taken up by solar cells, the more energy is produced. However, this also means that a larger surface area will need more financial backing, raising the costs even further. If this problem can be solved, then solar power will gain in popularity and prices will drop dramatically. However, until this happens, solar power will always remain on the fringes of the renewable energy type market. Although the literature review suggests that at the current time, none of these renewable energies are cost effective enough to warrant developing on a mass scale, it is the belief of the researcher that solar power energy is the least likely of the main four types to make expansive inroads into the virtual monopoly of fossil fuels on the energy industry.
The research underlines that wind power is perhaps the energy type that has the greatest chance of success at overtaking and replacing traditional non-renewable energy sources such as coal, oil and natural gas. This being said however, there are still a vast number of weaknesses in this process and the day when wind power overtakes the non-renewable energies is far from guaranteed.
In terms of cost, wind turbines and wind farms are relatively expensive. While on a personal level, the United Kingdom government will provide each household with a grant of £1000 per KW produced, on a mass production level, the cost of parts and installation make wind power still an expensive option, much more expensive than the traditional energy types. The case study highlights the success that wind turbines can have on a small scale. The example provided showed that wind power was both environmentally friendly and could save money compared to more traditional types of power. The success of the turbine making savings both financially and environmentally (2,145 CO2/yr in carbon savings and £330/yr saved) indicates that in the future, wind power could be a major player in the energy industry. The turbine also helped to reduce noise pollution in the case study, something that had great influence on the person involved. In the case study, however, the findings of the literature review were supported. The high start up costs (£14000 approx. in the case of George Jarvis) makes it an extremely expensive form of saving the environment and saving money effectively. While the long term effects would see financial savings, this is indeed a long term scheme and these savings will not offset the start up costs for quite some time.
There are other issues with wind turbines. An important consideration is the nature of the aesthetics of the energy type. The wind turbines, especially the horizontal axis turbines, are often seen as landscape pollution by locals who live in the region where they are established. While this may seem trivial, the persuasion of certain individuals and large groups cannot go unnoticed. A more important factor than how they look, with opinion split decidedly on that matter, is the issue of environmental effects. It is true that wind power is not the most environmentally unfriendly of the four energy types (that is Biomass energy if we go by the findings of the research), it is still apparent that there are negative factors involved in the construction of the wind turbines. This construction releases fine particles and carbon dioxide into the atmosphere.
If these factors are all taken into account, it is still evident that the government views wind power as possibly its greatest chance of finding a sustainable, environmentally friendly form of energy to replace the dwindling supplies of fossil fuels. The finances that they have ploughed into these wind farm projects and the current growth of wind farms in the UK of 25% per year is evidence of this. The cost of the energy form needs to be reassessed though because at £14000, the start up costs of a wind turbine is far too expensive for even the most hardened supporter of the technology.
Early indications from the research, both in terms of the literature review and the case study, stress that biomass energy could have an increasingly influential role in the development of renewable energy types to rival that of the more traditional types of power. If biomass energy is compared to that of wind power for example, the case study indicates that the start up costs (a key factor in whether each energy type will be successful or not) are much lower. The start up costs of the biomass woodchip burning boiler cost approximately fifty percent of the wind turbine in the second case study (In England however the grant towards this cost is lower in Scotland and set at a maximum of £1500: Appendix C). Unfortunately, due to secondary research difficulties, it was not able to compare the financial savings that the biomass energy model made with that of the wind turbine. However, it is possible to compare the carbon savings over a year period that both the wind turbine and woodchip burning boiler made and the results are favourable to biomass. The 11,500 kg CO2/yr, coupled with the lower cost imply that biomass could play a lead role in the future energy developments in the United Kingdom.
However, there are factors which weigh against the biomass energy type. The two main issues are of efficiency and the environment. In this modern age when the use of fossil fuel to form energy is criticised due to the negative effects on the environment, the fact that biomass energy is the largest offender in terms of acting negatively towards the environment out of these four renewable energy sources, is a critical blow to the support of biomass. While there is great support, as highlighted in the literature review and the case study, the negative environmental effects could prevent the energy type from ever becoming a key factor in the future.
The second issue is perhaps less important and developments should be able to fix it. However at the current time, the efficiency rating of the biomass technology rates it as between 25-35%, only higher than the efficiency rating of solar cells in this study. This low output of energy is a reason as to why the form has not taken a great amount of the UK energy industry yet. The literature review did highlight the key role that biomass energy has in the United States though, with it being the second largest renewable energy producer in the country after hydro power. This is a fact that cannot be ignored and if environmental factors can be fixed, then biomass energy could easily become a prime candidate ready to challenge for supremacy against fossil fuels.
The research stresses that geothermal energy, under its current guise, is perhaps the least developed of the four types of renewable energy in this study. Until recently the literature suggested that the development of geothermal energy was limited geographically to regions located close to tectonic plate boundaries. However, as the research suggests, there are possible sites within the United Kingdom that may offer opportunities to develop a geothermal base such as Cornwall. The research also suggests that out of the four main types of energy analysed, geothermal energy has by far the highest rate of efficiency, coming in at approximately 90-95%. This is higher than that of wind energy and far higher than those of biomass energy and solar cell energy that have an incredibly low efficiency level. The literature also highlighted that if successful, the project to develop geothermal energy in Cornwall had the capacity to supply ten percent of all electricity across the United Kingdom for the next one hundred years. This is still only an estimate (and an optimistic one at that) but it does highlight the possible potential that this form of energy could have.
The weaknesses of geothermal energy are that it is limited geographically (at the current time at least) and also the aesthetics of the energy plants created received perhaps the largest criticism in the literature review. It must also be stated that the construction of these geothermal energy power plants also have a considerably negative effect on the environment and this needs to be addressed before it is attempted on a mass scale. However, given the infant status of this energy and the technology that surrounds it, geothermal energy has perhaps the greatest chance of becoming the most complete competitor to the fossil fuel monopoly of energy supply in the United Kingdom over a long term period.
The research analysis, taking into account an investigation of the four main sources of renewable energy and after gaining an understanding of each of the energy types and their strengths and weaknesses, finds a number of issues with each of the prospective energy forms. While the government appears to be supporting the development of these energy types on a small scale setting (Appendix C), in truth the government grants are not enough to encourage a wide spread of these energy forms across the United Kingdom. They are all hindered currently by the expensive start-up costs or low efficiency that does not plague the more established fossil fuel energy types.
This is the most significant factor involved. The cost effectiveness of an energy type will decide how competitively it can compete with the established order. In this manner, none of the energy types currently meet this requirement. Over a longer period, there is a great chance of success, but this chance is as likely to fail. It depends on a number of developments, not least cost effectiveness and reliability that may or may not happen. If these renewable energies are to ever fully replace fossil fuels as the number one providers of energy in the United Kingdom, then these developments must be put in practice and soon.
Therefore, the evaluation of the research highlights that of the four energy types, perhaps the most suited to replacing the traditional energy types currently used in the United Kingdom today is that of wind energy, but a number of developments must occur first to make it financially viable and efficient enough on a large scale, before the United Kingdom can rely on it successfully as an mass energy source. At the current time there is no one particular renewable energy type that has all the positive attributes that could make it appealing to develop on a large scale. This needs to be addressed before any alternatives to fossil fuels can be successful.
The dissertation has highlighted that there are many possible forms of renewable energy that could ultimately replace the traditional fossil fuel energies of coal, oil and natural gas. However, perhaps the main realisation of the research, from the literature review and the case studies is that the development of each of these forms of energy is still in its infancy. The small percentage of the world’s energy supply provided by these renewable energy types at the present time, coupled with the high costs of development and installation highlight that the reliance on fossil fuels will remain in the United Kingdom for a little while longer.
However the research, particularly in the case study results, suggests that if these factors can be improved (cost being a pertinent issue), then the future prospects for these renewable energies look good. In the United Kingdom, the main focus recently has been on the improvements made in wind power but this is partly because it is the most widely developed and used of all of the technologies. Another consideration would be the use of wave power, given the status of the United Kingdom as an island and the abundance of supply of this energy type. The most suitable type of energy at the current time from the selection of solar power, wind energy, biomass and geothermal energy, as highlighted by the research is that of wind power. In terms of cost effectiveness and availability of the energy, wind power is perhaps the most successful. This is not however a glowing reference of wind energy in its current form. There are many weaknesses that can be attributed to it. However, when compared to the other types of energy it is the best possible option at the current time. This is likely to change. Solar power is too expensive, biomass is the most environmentally unfriendly of the four and geothermal energy is far too underdeveloped in the United Kingdom to see whether it could be a success of not. However, if these factors can be changed, then renewable energy may yet develop accordingly on a mass scale to be able to replace traditional non-renewable energy types that dominate energy production in the current era.
Therefore, there are no specific renewable energy types at the current time that could be a successful alternative for the fossil fuels that are used in society. However, with development and time, it is possible that any one of the four could become appropriately efficient, reliable, cost-effective and environmentally friendly that it could replace traditional fuels. It is also quite conceivable that a mixture of energies will share the energy market in the future, with an equal share for these four types. However, their future relies upon the support of the government to drive the development in this early and expensive stage, a factor that could be of immense importance as we move into the teenage years of the Twentieth Century.
The dissertation has highlighted a number of issues that could be improved on in the future. This is not uncommon with research as it is intrinsic to the field. However, as limitations in research are common, they should still be acknowledged, in the very least to warm future studies about certain pitfalls that exist. In this aspect, the research can provide potential researchers with a number of recommendations on how to improve research in this area.
Firstly it is important to note that the notion of this dissertation was perhaps overreaching in the first place. The decision to attempt to find an alternative energy source is still in its relative infancy on a global scale and therefore for this work to provide conclusive evidence supporting either one or a combination of energy types was perhaps too naive in its outlook. The work however does provide some important points and these should not be overlooked. A more narrow focus, perhaps looking at just one energy type may have been more suitable in enabling the researcher to fully analyse the strengths and weaknesses of just one type, rather than have to analyse four, which ultimately led to difficulties and a lack of focus. The work would also have benefitted from a focus on wave power, given the nature of the United Kingdom as an island, with wave power supplies in abundance. The literature provided many examples of the success of wave power and should have been included in the research question.
Another limitation was the difficulty due to the lack of literature focused on results. The United Kingdom has developed solar power technology and wind power for some time but the focus on biomass energy and geothermal energy proved problematic due to the relatively new status in the United Kingdom of these latter energy types. It was difficult to gain information on geothermal energy in particular and the information provided had to be relied upon from other countries rather than the United Kingdom, with the United States providing the majority of the information. However, that being said, it is important to realise that research into particular issues has to begin somewhere and so the unusual research aims of this dissertation could act as a starting point into future research concentrating geothermal energy and its possible success in the United Kingdom.
Nevertheless, the research did provide some excellent information based on the research criteria and despite the limitations, the research aims were met with the evidence that certain types of energy can be successful, even if only on a small scale, at replacing traditional fossil fuels as the source of energy in the United Kingdom. The recommendations provided here can be of vital use to future researchers in this particular area of renewable energy research, displaying key factors of a successful research project and the need to narrow the focus of any research that will attempt establish one particular energy type as a possible successor to the more conventional and traditional non-renewable energy types of coal, oil and natural gas.
6.2: Possible areas of further research
The nature of the research carried out allows a number of possible areas of further research to be undertaken. Firstly, one of the major limitations of the work was that too much was attempted. It would be much more effective for researchers to focus on just one particular area of research and develop the knowledge and possible future of that one specific energy type.
Another key area to research, given the geographical status and location of the United Kingdom, is that of wave power. While the four renewable energy forms covered in this work are important to the future of sustainable energy forms, the nature of the United Kingdom lends itself perfectly to wave power. A research piece on the strengths and weaknesses of wave power would be an apt topic for renewable energy within the United Kingdom and should be completed as soon as possible. This would allow further research into a fifth possible type of renewable energy that could ultimately reduce the dependency on fossil fuels.
Any further research would need to also use a much larger sample size than the one used in this research. It would be sensible for the researchers to narrow down to one particular energy type, (we can use wind energy as an example) and then use a wind farm as a possible case study, measuring the longitudinal efficiency and reliability over a number of years and how it can possibly replace the non-renewable energy types. This research would be far too expensive for this researcher to undertake but receiving a grant could allow additional research to take place. The full cost and efficiency levels of certain energy types will not be known until a large sample research study takes place and this is one of the key findings of this analysis.
These areas for possible future research should help provide potential researchers with ideas of how to develop this study, or at the very least offer new routes of research that have not yet been attempted, particularly in the form of researching wave energy and the possibilities that this could have for the United Kingdom energy supply in the future.
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