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Energy Sources. Historical Perspective. The Sun. Oldest source of energy Sustains life on Earth Provides light and heat energy Photosynthesis is fuelled by the Sun – we get all our energy from plants Historically however, humans could not harvest the Sun’s energy.
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Energy Sources Historical Perspective
The Sun Oldest source of energy Sustains life on Earth Provides light and heat energy Photosynthesis is fuelled by the Sun – we get all our energy from plants Historically however, humans could not harvest the Sun’s energy
Humans began generating energy this way between 500000 and 700000 years ago • Used for warmth, light and preparing food • Also used the heat created from burning wood to transform other materials (e.g. clay into brick, and making metal tools) • People were dependent on wood • As population increased, use of wood increased, which created a shortage of wood in some areas Wood
Coal Non-renewable energy source Hard, black substance Is a fossil fuel, made from animal matter that was compressed deep underground
Began to be used as an alternative source of energy (to wood) The use of coal started the industrial revolution Was the source of energy for the steam engine Creates lots of pollution in the form of nitrous oxides which depletes the ozone layer
Whale Oil Used around the 1700’s until the late 1800’s Was widely used in oil lamps as historically it was cheap Couldn’t be sustained (i.e. not enough whales to sustain required amounts of oil) Eventually replaced by kerosene