Alternative Resources Layered Curriculum Notes Swainston MS Science 8 1

Alternative Resources Nonrenewable Resources – Fossil Fuels Coal, crude oil (petroleum), natural gas – Biomass Renewable Resources – Wind Energy – Solar Energy – Hydroelectric Energy – Tidal Energy – Geothermal energy 2

Fossil Fuels 3 Fossil fuels are formed by the anaerobic decomposition of remains of organisms including phytoplankton and zooplankton that settled to the sea (or lake) bottom in large quantities under anoxic conditions, millions of years ago. Fossil fuels are oil, coal and natural gas. In 2006 primary sources of energy consisted of petroleum 36.8%, coal 26.6%, and natural gas 22.9%, amounting to an 86% share for fossil fuels in primary energy production in the world.

Crude Oil Crude oil is a smelly, yellow-to- black liquid and is usually found in underground areas called reservoirs. Scientists and engineers explore a chosen area by studying rock samples from the earth. Measurements are taken, and, if the site seems promising, drilling begins. 4

Natural Gas Natural gas is a gas consisting primarily of methane. It is found associated with fossil fuels, in coal beds. It is created in marshes, bogs, and landfills. 5

Coal Coal is a readily combustible black or brownish-black sedimentary rock normally occurring in rock strata in layers or veins called coal beds. At current usage, the coal supply will last 1500 years. However at a 5% growth rate the coal supply will last only 86 years. 6

Biomass Biomass is made up of organic material of animals & plants It is stored energy from the sun. Biomass makes up 4% of the US use in energy. 7

Alternative Resources Nonrenewable Resources – Fossil Fuels crude oil (petroleum), natural gas – Biomass Renewable Resources – Wind Energy – Solar Energy – Hydroelectric Energy – Tidal Energy – Geothermal energy 8

Wind Energy 9 Wind is simply air in motion. It is caused by the uneven heating of the Earth's surface by the sun. Daily Wind Cycle During the day, the air above the land heats up more quickly than the air over water. The warm air over the land expands and rises, and the heavier, cooler air rushes in to take its place, creating wind. At night, the winds are reversed because the air cools more rapidly over land than over water. Used to convert wind energy to electric power using turbines.

Solar Energy Solar Energy is better for the environment than traditional forms of energy. Solar energy has many uses such as electricity production and heating of water through photovoltaic cells and directly for drying clothes. Solar energy is responsible for weather patterns and ocean currents. Clouds, pollution and wind can prevent the sun's rays from reaching the earth. 10 Other Interesting Facts about Solar Energy: Da Vinci predicted a solar industrialization as far back as In one hour more sunlight falls on the earth than what is used by the entire population in one year. A world record was set in 1990 when a solar powered aircraft flew 4060km across the USA, using no fuel. Fierce weather cost the world a record $130 Billion in the first eleven months of more money than was lost from weather related disasters from 1980 to 1990 ($82 Billion).

11 *Photovoltaic Cells* We have a solar farm in our valley at Nellis AFB

Photovoltaic Cells What are they? – Thin wafers of silicon Similar to computer chips Much bigger Much cheaper – Silicon is abundant (sand) Non-toxic, safe – Light carries energy into cell – Cells convert sunlight energy into electric current-they do not store – Sunlight is the “fuel” 12

Hydroelectric Hydropower is the renewable energy source that produces the most electricity in the United States. It accounted for 6% of total U.S. electricity generation and 67% of generation from renewable resources in Relies on the water cycle Mechanical energy is harnessed by hydropower 13

Tidal Energy The power of the tides can be harnessed to produce electricity.produce electricity Similar to the more conventional hydroelectric dams, the tidal process utilizes the natural motion of the tides to fill reservoirs, which are then slowly discharged through electricity- producing turbines. Advantages – Tides rise and fall every day in a constant pattern – No fuel to run the plant – It produces clean energy Disadvantages – Altering the ecosystems – Only produces energy when there are tidal serges – Only available in small number of regions 14

Geothermal Energy The energy stored in the mantle of the earth is harnessed from the internal heat of the planet and can be used to generate steam to run a steam turbine. This in turn generates electricity, which is a very useful form of energy. Advantages – Cost of land is usually less expensive – Low running costs – Clean energy with no pollution Disadvantages – Must be harnessed from deep within the earth – Harmful gases come from the sites – Suitable hotspots are located near fault lines and volcanoes 15