'We have 5 guest/s online'
Types Of Energy
8.2.1 List the main forms of non-renewable energy sources.
Consider coal, oil, timber and gas.
Non-renewable energy sources are energy sources they cannot be replenished in a short period of time (that of a human lifetime.
Oil - Crude oil is a smelly, yellow-to-black liquid and is usually found in underground areas called reservoirs. Oil was formed from the remains of animals and plants that lived millions of years ago in a marine environment before the dinosaurs. Over the years, layers of mud covered the remains. Heat and pressure from these layers helped the remains turn into what we today call crude oil.
Natural Gas - Millions of years ago, the remains of plants and animals decayed and built up in thick layers. This decayed matter is called organic material. Over time, the mud and soil changed to rock, covered the organic material and trapped it beneath the rock. Pressure and heat changed some of this organic material into coal, some into oil (petroleum), and some into natural gas. The main ingredient in natural gas is methane, but can also contain propane or other natural gases.
Coal - Coal is a combustible black or brownish-black sedimentary rock composed mostly of carbon and hydrocarbons. It is the most abundant fossil fuel produced in the United States. Coal is a non-renewable energy source because it takes millions of years to create. The energy in coal comes from the energy stored by plants that lived hundreds of millions of years ago. The heat and pressure from the top layers helped the plant remains turn into what we today call coal.
8.2.2 Discuss the efficiency of conversion of fossil fuels into electrical energy.
See also teacher’s notes in 8.1.1. Fossil fuel burning is an extremely inefficient method of energy conversion. Coal is least efficient (about 30%), then oil (about 35%) and gas (about 40%). Waste energy is dissipated into the atmosphere or water (lake, sea or river).
8.2.3 Outline how modern industrial societies have become dependent on non-renewable fossil fuels as the major sources of energy supply and electricity production.
There are cheap and plentiful supplies for electricity production and other energy needs. However, the depletion of supplies of coal, oil and gas challenges continuity of supply in the longer term.
Modern industrial societies have become dependent on non-renewable fossil fuels as the major sources of energy supply for several reasons. The use of non-renewable fossil fuels has become more popular in industrial societies due to the low cost. Most industrial countries such as egypt need to have low running costs to allow all the small and cheap factories to stay afloat. That said, the re-newable energy sources at the moment, are not currently available to poorer countries and are also not reliable. Further more, the renewable energy sources to not posses the power needed to run a factory let alone a society of factories
8.2.4 Outline the main pollutants produced from the large-scale burning of fossil fuels worldwide.
Sulphur emissions cause acid rain; CO2, although not strictly a pollutant, contributes to the enhanced greenhouse effect.
Sulphuric acid – The burning of fossil fuels creates sulphur dioxide (SO2), which is a pollutant gas generally harmless if handeled in small quantities. In larger quantities it reacts with moisture meaning atmospheric water and oxygen to create sulphuric acid (H2SO4). This sulphuric acid produced in rain clouds rains down acid rain which is very damaging to the environment by lowering the pH of soil and fresh water and also causes weathering in statues and structures.
Carbon Dioxide – The burning of fossil fuels has resulted in a 25% increase in the amount of carbon dioxide in our atmosphere. Carbon dioxide is a greenhouse gas which traps heat from the sun in the atmosphere thus contributing to global warming and causing the surface temperature of Earth to rise.
Coal and oil are fossil fuels and burning them releases smoke pollution and an incredible amount of carbon dioxide into the air.
8.2.5 Describe the main effect of carbon dioxide emissions from the large-scale burning of fossil fuels.
Enhanced greenhouse effect leads to higher mean global temperatures, sea-level rise and general climate changes.
The atmosphere acts as a filtering system, letting in only some frequencies of electromagnetic energy. Different gases absorb different frequencies of light and carbon dioxide keeps infra-red radiation from passing. Infra-red radiation is the radiation is the radiation emitted by the earth at night after it absorbed sunlight all day. It is also the frequency responsible for heat and not light. For that reason, the carbon dioxide raises the temperature through letting the heat "bounce" between it and the surface of the earth.
8.2.6 Discuss the use of technologies to make energy conversion from fossil fuels more efficient and cleaner.
Consider clean coal technology.
8.2.7 Discuss two approaches to reducing the enhanced greenhouse effect based on international agreements to reduce emissions of CO2 and the promotion of clean technologies.
Consider the Kyoto Protocol, which uses economic mechanisms, and the Asia-Pacific Partnership on Clean Development and Climate (APPCDC), which looks at technology solutions.
The Kyoto Protocol is an international agreement linked to the United Nations Convention on Climate Change. The major feature of the Kyoto Protocol is that it sets binding targets for 37 industrialised countries and the European community for reducing greenhouse gas (GHG) emissions .These amount to an average of five per cent against 1990 levels over the five-year period 2008-2012.
The Kyoto mechanisms are:
These mechanisms help stimulate green investment and help Parties meet their emission targets in a cost-effective way.
The Kyoto protocol is also designed to assist countries in adapting to the effects of climate change. It facilitates the development of techniques that can help increase resistance to the impacts of climate change. And in that way it uses economic mechanisms, to help implement its approach in reducing the enhanced greenhouse effect.
On the other hand, the Asia-Pacific Partnership on Clean Development and Climate uses technology solutions as a means to improve global warming effects. However, unlike the Kyoto protocol this agreement allows member countries to set their goals for reducing emissions individually, with no mandatory enforcement mechanism. It creates a voluntary, non-legally binding framework for international cooperation to facilitate the development, of more efficient technologies in cooperation, so as to achieve practical results. There has been debate however that the APPCDC is 'useless' as it is non-binding, like the Kyoto protocol which is a mandatory development program.
8.2.8 List the main forms of renewable energy sources
Consider wind, solar, tidal, wave, hydroelectric and biomass.
Wind power: is the conversion of energy found in wind into a useful form of energy in numerous ways such as electricity using wind turbines. This method is very useful and environmentally friendly but the amount of energy production depends on the wind speed so it is unusually not that productive. It only produces 1% of worlds electricity but in some countries like Denmark it counts for almost 20%, 9% in Spain and 6% in Germany and the Republic of Ireland.
Tidal power (tidal energy): is a hydro-power that converts the energy of tides into electricity or other useful forms of power. However not yet widely used even though tides are more predictable than wind energy and solar power.
Solar power: is the light and heat from the Sun converted into energy. This method has been around since ancient times. In modern days the suns light and radiant heat is considered to be one of the most successful forms of renewable energy source.
Biomass: is biological material extracted from living, or recently living organisms such as wood, waste, and alcohol fuels. Biomass is usually plant matter grown to create electricity or produce heat.
Wave: energy collected from the energy from ocean surface waves, by capturing the energy of the waves. the Wave power generator is not widely used technology but it was first used around 1890s. There are many types of devices that harness wave energy and new prototypes are being developed rapidly.
8.2.9 Explain why there is increasing pressure to use renewable energy sources.
Consider higher cost of oil, political instability, security of supply, greenhouse effect leading to climate change, and other pollution.
Widely used fossil fuel or oil prices are getting higher and people are worried about the environment and the sustainability of the product. To add to this the gases produced from the burning of fossil fuel are significant contributors to the "green house" effect which is the main cause of "global warming" so government policies and non-governmental agencies and environmental activist groups are pushing to change to a more sustainable/renewable source of energy other then fossil fuel.
8.2.10 Discuss the limitations of the use of renewable energy resources as alternatives for fossil fuels.
Limitations include high cost, unreliable supply and low energy density.
Alternatives for fossil fuels are usually not effective because of the issues like storage, transporting of the alternative fuels and also most of them are in control of nature. For example if there is no strong wind, relying on wind power is useless, solar panels will only produce sufficient energy when the northern hemisphere of the planet is tilted towards the sun. Also putting alternative energy sources in use can be expensive to implement into our already set up infrastructure and most importantly fossil fuels are still cheaper than any alternative fuels right now.
8.2.11 Discuss the advantages and disadvantages of nuclear power.
Very low CO2 emissions, high energy density versus safety issues, high cost of decommissioning, possible radioactive contamination, waste product storage problems, and link with nuclear weapons.
Advantages of nuclear power generation:
Disadvantages of nuclear power generation:
8.2.12 Discuss the role of energy conservation in energy policy.
Reduced usage by sustainable development policies, for example, sustainable transport systems and building systems (see also “Topic 12: Sustainable development”).
8.2.13 Outline new sources of energy.
Biomass production: This is where garbage or other renewable sources such as corn and vegetables are used to produce electrical energy.
8.2.14 Discuss the contribution of biomass as a renewable energy resource.
Can replace petrol in the internal combustion engine and be used as a biomass fuel.
Numbered list and italicised paragraphs are excerpted from Design Technology: guide. Cardiff Wales, UK: International Baccalaureate Organization, 2007.
Images are clickable links to its location.