Pros and Cons: Energy Sources

Pros and Cons: Energy Sources — page 5 — ENERGY SOURCES Cleaner Coal Coal is an inexpensive and abundant fuel source that is used by many nations to meet their energy needs China is currently leading the world in its production of large coal-fired power stations But coal is a dirty fuel that emits more CO2 per unit of electricity than either oil or natural gas Proposed carbon capture and storage CCS technologies offer ways to reduce the impact of burning coal The CO2 is collected as the coal is burned and then the gas is pumped into rocks deep below the ground Empty oil fields are other possible storage sites CO2 is already being injected into near-empty wells as a way of forcing out any remaining oil About 38 5 million tons 35 million tonnes of CO2 are injected into U S oil wells each year New coal-fired CCS power stations could capture up to 95 percent of the carbon in coal and dramatically reduce emissions Coal at the Jing Hua Gong coal mine in Shanxi China is loaded into a truck for transportation to one of China’s coal-fired power stations China’s reliance on relatively low-quality coal has made it one of the world’s largest emitters of carbon dioxide

Pros and Cons: Energy Sources — page 6 — Energy From Fossil Fuels PROS ENERGY FROM COAL Carbon capture and storage CCS greatly reduces the impact of burning coal on global warming The storage methods are considered safe and are expected to retain 99 percent of the CO2 injected into them over 1,000 years CCS allows the continued use of coal as an inexpensive and widely available fuel CONS ENERGY FROM COAL CO2 emissions are only one of many problems of burning coal for energy Mining coal is also dangerous and environmentally harmful It is estimated that in 2010 more than 2,400 workers were killed in Chinese coal mines as a result of floods cave-ins or explosions Mining scars the landscape and pollutes the air and water and the burning of coal releases a wide range of pollutants in addition to CO2 The biggest problem with coal however is that it is nonrenewable and will one day run out or become too expensive to use Types of Coal There are three main types of coal They vary according to the pressure under which they were formed and how much carbon they contain Each L ign ite is a d ry and c rumb ly coa l con ta in ing on ly abou t 50 pe rcen t has different qualities carbon Also known as brown coal it gives off the least heat and the is a harder coal containing more carbon than lignite It is the most common coal and burns with a good heat but it still Anthracite is a very hard black coal that is about 90 percent carbon It burns at high temperatures giving off the most heat and the most pollution Bituminous coal causes pollution least pollution 9

Pros and Cons: Energy Sources — page 7 — ENERGY SOURCES Energy to Change the World Oil has changed the world more than any other energy source It provides people with the fuel to run cars and fly airplanes and is for many nations the main fuel for generating electricity Oil is also the raw material for making many plastics paints fertilizers fabrics cosmetics and countless other goods and materials Oil is normally found in high-pressure wells deep underground It is released by drilling into the wells from the surface In places where the pressure is lower pumps are used to extract the oil or water gas or steam is injected to force the oil to the surface Over the years the oil industry has developed technology The 800-mile 1,287-kilometer Trans-Alaska Pipeline carries oil from remote regions of Alaska to the port of Valdez Some people consider projects such as this to be too costly and say that they endanger habitats and wildlife 10

Pros and Cons: Energy Sources — page 8 — Energy From Fossil Fuels to drill deeper and in more remote locations for example at sea where offshore platforms access oil that lies deep beneath the seabed The value of oil is so great that it is sometimes referred to as black gold It is found only in certain parts of the world yet it is needed and used worldwide The Middle East is particularly rich in oil and that has led to struggles to control the region’s reserves In some areas the exploration of oil reserves has caused controversy because of its impact on the local environment and wildlife Proposals to drill for oil in Alaska’s Arctic National Wildlife Refuge for instance have caused heated debate New Oil Technology With oil supplies running out oil companies are looking at new technologies to extract oil from unconventional sources One technology being developed is the extraction of oil from tar sands The oil is contained in the bitumen or tar that makes up about 10 percent of most of those sands the rest being clay sand and water The bitumen must be separated using a lengthy and expensive process and then purified and thinned before it can be used as oil Tar sands are found in various parts of the world but their exploitation is most developed in Alberta Canada where around one million barrels of oil are produced each day VIEWPOINT New Source Same Problem The search for new sources of oil is leading to ever more expensive and elaborate technologies Many environmentalists question the continued focus on oil-based energy however because producing it and using it creates pollution It takes about 29 kilograms 64 pounds of CO2 to produce a barrel of oil conventionally That figure can be as much as 125 kg 275 lbs for tar sands oil Tar sands extraction also has the potential to kill off or damage the vast forest wilderness in Canada greater than the size of England and Wales Mike Hudema Climate and Energy Campaigner Greenpeace Canada 11

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