Transcript Energy
Energy Types of Energy Fossil Fuels 1. Petroleum ► Oil was formed from the decomposed bodies of plankton buried in the muds of shallow seas. ► Over millions of years, these organic liquids were transformed by pressure and chemical reactions into small drops of petroleum. ► The oil mostly accumulated into petroleum traps Petroleum Advantages ► Plentiful ► Relatively cheap source of energy ► Easy to transport Disadvantages ► Pollution ► Becoming more expensive ► “addiction to oil” ► nonrenewable 2. Natural Gas ► Like oil, natural gas is formed from the remains of plankton that fell to the sea bottom and were covered by fine muds and silts. ► These remains were altered over millions of years into gasses. ► They accumulated into the same traps that contain the oil. ► Natural gas was regarded as a useless by product for years, however since the 1950’s it has gained prominence. Natural Gas Advantages ► Cleaner burning than oil. Less pollution ► Many known reserves Disadvantages ► Difficult to transport (pipelines or LNG) ► Still create pollution issues. Add to global warming ► nonrenewable 3. Coal ► Coal is the third nonrenewable fossil fuel. ► It was formed from the remains of ancient forests and swamps. ► As trees and other plants died, leaves and branches fell into the swamps. ► Unable to decay in the waters they accumulated to form thick layers of vegetable remains ► These were buried over millions of years by sediments and the remains of other swamps. ► Pressure and chemical changes turned the sediments into sedimentary rocks and the vegetable remains into coal. Three types of coal 1. Anthracite - produced under areas of high pressure and is carbon rich. 2. Bituminous – softer than anthracite, it contains more impurities, and was formed under less pressure. 3. Lignite – a soft, low value coal formed close to ground level where pressure was greatly reduced. Coal Advantages ► For many years it was cheap, readily available, and easy to transport Disadvantages ► Highly polluting ► Reserves are getting more expensive to mine ► nonrenewable Thermal Power ► Thermal power is considered a secondary energy source. ► It uses a primary energy resource such as the fossil fuels to create the energy. ► The fossil fuels are burned to heat water to create jets of hot steam under high pressure. ► The steam forces the turning of turbine blades which then turn generators which produce electicity. Thermal Power Advantages ► It can be produced from a variety of fuels. ► It can be cheaper than many other forms of electricity ► Plants can be located close to high demand areas ► Plants can be shut down or restarted as needed. Disadvantages ► Pollution from the burning of fossil fuels. ► Scrubbers are expensive to install ► They rely on nonrenewable sources of energy. Nuclear Power ► Another secondary energy source. ► The methods are similar to thermal power. ► The main difference is the heat source is generated by splitting atoms of radioactive materials, such as uranium-235, in a process called nuclear fission. Nuclear Power Advantages ► Originally considered to be low cost. And pollution free. Disadvantages ► Complex safety and back-up systems needed to guard against break downs in the reactors have made the cost expensive ► Overall safety concerns Hydroelectric Power ► Dams are constructed to raise water levels and create an artificial drop. ► The falling water turns tubines, which in turn drive the generators that convert the mechanical energy of moving water into electrical energy. Hydroelectric Power Advantages ► Clean and safe ► Abundant in some areas Disadvantages ► Lack of suitable rivers in many areas ► Expensive initial investment ► Disruption of wildlife habitats ► Destruction of forests and ecosystems