Analysis at work:
Producing Electricity
Introduction:
Oil is a liquid fossil fuel and is formed from layers and layers of buried animals and plants that have been under a lot of heat and pressure over a long time. Oil is a non-renewable resource as it cannot be produced on human time frame.
Oil is used for many things; it’s used for transportation, heating purposes, fuel for electricity generating plants. Fuel is found underground reservoirs.
The production of electricity from oil begins with the extraction of oil and ends with the oil burning in boilers and turbines at power plants. Crude oil is removed from the ground by drilling deep wells and pumping it up to the surface.
The crude oil is then moved to a refinery (refineries remove a portion of the impurities in the oil, e.g. metals) where it is refined into a number of fuel products: kerosene, gasoline, liquefied petroleum gas
(propane).
Then this crude oil is moved to power plants by trains, trucks, pipelines or ship. Many methods are used at the power plants to generate electricity from oil. One of the methods is to produce steam by burning the oil in the boilers which is used by a steam turbine to generate electricity. Another common method is to use combustion turbines to burn oil.
In a fossil plant, oil, gas or coal is fired in the boiler, which means that the chemical energy of the fuel is converted into heat.
Energy transfer diagram:
Sun→Light Energy→Photosynthesis→Plants/Animals→Fossil Fuels
The sun is the starting point for this energy chain, the source of the suns energy if nuclear fusion.
Formation of oil:
Layers of the dead sea creatures settle on the sea beds
Layers of sedimentary rock build up on the top
The oxygen and pressure from these rocks, along with the absence of pressure, mean that oil is formed over millions of years.
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Peer Reviews
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Quality of writing
This piece of work is well written, the candidate provides accurate information relating to the topic and they have used suitable scientific terms. In addition to this the information is carefully laid out and is essay is easy to follow, furthermore there are no issues with spelling or grammar.
Level of analysis
It is clear from the level of detail provided that the candidate has taken the time to research this topic, which is always a good idea. Its shows interest and enthusiasm in you subject and makes your essay more enjoyable to read. In addition to this the candidate has also included a bibliography, which I recommend, it is important to provide links to any web pages you have used, it prevents you being accused of plagiarism and it shows the preparation you have undergone in order to write your essay. Furthermore the candidate has accurately shown the necessary calculations in order to work power and efficiency, this shows a good understanding of the mathematics involved in physics principles. Finally the candidate gives a reasonable evaluation, they have provide a personal response which helps bring your work to a close. However you should end your essay by summarising your key points as this helps bring together any lose ends. In addition to this the candidates essay ends with calculations, it would more appropriate to end with a brief sentence explaining how this backs up your point.
Response to question
The candidate starts this essay by describing oil, though they do so well, the purpose of the essay is not clear. When writing an introduction you need to state the topic that you will be writing about so that the premise of your essay is clear. You should also try to engage the reader, you can do this by providing historical background or by stating a relevant fact or quote that you find interesting. That said, the candidate gives a very explicit response overall, they have included a great deal of information and they have taken the time to put together a table and a flow chart, these can be useful tools for make the information more interesting to read.
