Alternative Energy Resources. Environmental Earth Science Rev 2018, Spds 2011

Transcription

1 Alternative Energy Resources Environmental Earth Science Rev 2018, Spds 2011

2 Energy Sources Sun is the ultimate source of most energy on Earth. The Sun s energy is transferred from photosynthetic organisms to all other living things. Fossil fuels, such as natural gas, coal, and petroleum, are non-renewable resources formed from organisms that lived millions of years ago. Burning of fossil fuels releases sulfur and nitrogen oxides into the atmosphere, and thus contributes to air pollution. Burning produces carbon dioxide and water vapor (greenhouse gases) which may contribute to global climate change. (Remember combustion equation?)

3 Forming fossil Fuels All fossil fuels begin as organic matter trapped in sedimentary rock. Fossil fuels form over geologic time as a result of the compression and partial decomposition of plants and other organic matter. The high concentration of carbon and hydrogen in fossil fuels makes them very efficient energy sources. (Remember all the covalent bonds?)

4 Distribution of Oil Reserves

5 Petroleum Reserves 48% of the world's total crude oil production came from five countries: Russia 13%, Saudi Arabia 13%, United States 11%, Iraq 6%, Iran 5% (2016)

6 Petroleum Consumption Consumption not evenly distributed. Industrialized nations use most. However fastest growth in consumption is in China. China and India have 60% of world s population. Imagine what will happen when they all can acquire the petroleum based products we have!

7 Crude Oil is a Mixture Crude oil is a thick black mixture of many types of hydrocarbons. This mixture is refined to separate the mixture into useable products.

8 Oil Refining Refining is called fractional distillation Compounds are separated by their boiling points Boiling points are directly related to the size of the molecule The larger the molecule (more carbons) the higher the boiling point)

9 Additional steps after distillation

10 Coal Another fossil fuel Coal is a combustible black or brownish-black sedimentary rock with a lot of carbon. Coal is a nonrenewable energy source because it takes millions of years to form. Coal contains the energy stored by plants that lived hundreds of millions of years ago. Anthracite has 86% 97% carbon Bituminous coal has 45% 86% carbon Subbituminous coal has 35% 45% carbon Lignite has 25% 35% carbon and has the lowest energy content The two largest coal mines in the United States are the North Antelope Rochelle and Black Thunder mines in Wyoming. Together, the two mines produced 22% of total U.S. coal production in 2016.

11 Distribution of Coal Reserves Worldwide

12 Downside of Coal Use In addition to being a non-renewable resource, the mining of coal negatively impacts the environment Whole mountains are demolished to remove coal Air pollution from burning coal Sulfur dioxide (SO 2 ), which contributes to acid rain Nitrogen oxides (NOx), which contribute to acid rain & smog Particulates, which contribute to smog Mercury and other heavy metals

13 Natural Gas Another Important Fossil Fuel Natural gas occurs deep beneath the earth's surface. Natural gas consists mainly of methane, CH 4. Demand for natural gas changes, while production stays the same. Natural gas is stored in large volumes in underground. The United States has relied less on natural gas imports in recent years, mainly because of increases in U.S. natural gas production.

14 Nuclear, a non-renewable option Nuclear energy is energy in the core of an atom Nuclear fission = atoms are split apart, which releases energy. All nuclear power plants use nuclear fission, and most nuclear power plants use uranium atoms.

15 Nuclear Power Nuclear energy produces radioactive waste. Materials remain radioactive and dangerous to human health for thousands of years WHAT DO YOU DO WITH THEM? WHERE DO YOU STORE THEM? Nuclear power creates electricity in the same way as burning coal, oil, or natural gas water is boiled to turn a turbine

16 Nuclear Power Facilities - Worldwide

17 World energy consumption with projections

18 Energy by Source in the US

19 Energy consumption per capita versus the GNP per capita The graph plots the per capita energy versus the per capita income for all countries with more than 20 million inhabitants urces_and_consumption

20 Alternative Energy Alternative energy resources, such as solar energy, water, geothermal energy, wind and biomass, can supplement dwindling conventional energy resources. Solar energy is unlimited, but technological advances are needed to find practical solutions to collect and store it. Hydroelectric, Geothermal, and Wind energy are limited to areas with these features nearby.

21 Solar Resources in the U.S. Photovoltaic cells convert sunlight into electricity. Use is limited to sunny locations, no clouds, and daytime operations. Photovoltaic cells have become affordable for homeowners, and large arrays are more commonplace.

22 Use of Solar Energy Solar energy do not produce carbon dioxide. Solar energy systems on buildings have minimal effects on the environment. Amount of sunlight and intensity of sunlight varies by time of day and location

23 Potential Wind Power

24 Hydroelectric is Renewable Largest renewable energy source for electricity generation in US 2016, hydropower accounted for about 6.5% of total U.S. electric by utilities Hydroelectric power is produced from moving water change in elevation from one point to another determines the amount of available energy in moving water Falling water pushes blades in a turbine to spin a generator to produce electricity Hydropower produces clean electricity, but hydropower does affect the environment

25 Moving Water Has Energy Not all hydropower worldwide is from falling water. Tidal power uses the predictable tides for energy. Requires a tidal range of at least 10 feet. Delta Works, Netherlands Waves form as wind blows over the surface of open water in oceans and lakes. Ocean waves contain tremendous energy

26 Wind Power Wind is caused by uneven heating of the earth's surface by the sun Wind turbines use blades to collect the wind s kinetic energy. Wind flows over the blades which causes the blades to turn. The blades are connected to a drive shaft that turns an electric generator, which produces the electricity. Big growth in wind energy in US. 2016, wind turbines in the United States were the source of nearly 6% of total U.S. utilityscale electricity generation.

27 Geothermal Resources in U.S.

28 Geothermal Most geothermal resources are near tectonic plate boundaries Geothermal heat pumps use the constant temperatures near the surface of the earth to heat and cool buildings. Geothermal electricity generation requires water or steam at high temperatures (300 to 700 F). generally built next to geothermal reservoirs All of Iceland is powered with geothermal electricity and heat

29 Biomass Resources in the US

30 Biomass Biomass is organic material that comes from plants and animals, and is a renewable source. Burning is only one way to release the energy in biomass. Biomass can be converted to other useable forms of energy, like ethanol and biodiesel. When burned, it still produces CO 2, but it is not releasing carbon from ancient organic material.