FOSSIL FUELS, THEIR IMPACTS, & ENERGY CONSERVATION

Energy  Where does it come from?

What is energy?  Ability to do work  Energy Source – Provides heat, chemical, nuclear, mechanical, or radiant energy.

Sources of Energy  Earth’s Core  Geothermal Energy  Gravitational pull of the moon and the sun  Solar Energy  wind patterns, hydrologic cycle, photosynthesis  biomass  Fossil Fuels  oil, coal, natural gas

Energy SourceType of Energy Crude OilNonrenewable Natural GasNonrenewable CoalNonrenewable Nuclear EnergyNonrenewable Biomass EnergyNonrenewable HydropowerRenewable Solar EnergyRenewable Wind EnergyRenewable Geothermal EnergyRenewable Tidal & Wave EnergyRenewable Energy Sources We Use Today

Fossil Fuels  Highly combustible substances formed from the remains of organisms from past geological ages.  Dominant Source of Energy  transportation, heating, cooking, electricity.  Nonrenewable

Fuel created from “fossils”  Produced when organic material is broken down in an anaerobic environment  Bottoms of deep lakes, swamps, shallow seas  Chemical composition subject to various temperatures, & pressures  coal, oil, natural gas.

Fossil Fuel Reserves  Localized & unevenly distributed  How long will they last? 1. Extraction 2. Consume 3. Imports & Exports

Worldwide Fossil Fuel Distribution

Coal  Organic matter, compressed under high pressure to form dense, solid carbon structures.  Most Abundant

Coal Mining  Subsurface mining – shafts are dug deeply into the ground & networks of tunnels are dug or blasted out to extract coal  Strip mining – coal deposits near surface, heavy machinery to remove huge amounts of earth to expose coal.  Mountaintop removal

Mining Economics  Land Area – must be surveyed and quantified  Land Reclamation  Ore – rock that contains minerals with important elements including metals.  Coal & Ore unevenly distributed

Cookie Mining Pre-Lab Questions  What economic considerations should be considered during this simulation?  What do the chocolate chips represent?  What are ores?  How many cookies does each miner obtain? How many mining tools?  What does “reclamation of land” mean?

Surface Mining Control & Reclamation Act of 1977  Regulate Surface Coal Mining & Reclamation Activities  Mandatory Standards to minimize impacts on fish, wildlife, other related environmental impacts.

Coal varies in its qualities  Vary in amounts of heat, pressure and moisture involved in its formation.  Peat – precursor to coal, remains wet & near the surface  4 types of Coal  different amount of energy 1. Lignite (least compressed) 2. Sub-bituminous 3. Bituminous 4. Anthracite (most compressed)

Formation of Coal

Impurities in Coal  Sulfur, mercury, arsenic  Sulfur content  Freshwater or Saltwater Sediments 1. Produces sulfate air pollutants, industrial smog and acidic deposition.  Combustion of Mercury  accumulates in organisms tissues, poisoning animals in food chains

Acidic Deposition  Acid forming pollutants from the atmosphere  Many Effects on the Environment 1. Leach nutrients from soil 2. Elevate toxic elements in water systems 3. Reduce species diversity and abundance in aquatic life 4. Damage agricultural crops

How is Electricity Generated?

Clean Coal?  Seeking ways to cleanse coal of its impurities to minimize impact on health and the environment

Natural Gas  Consists of Methane & varying amounts of hydrocarbons  Fastest growing fossil fuel, provides one-quarter of global energy.  Cleaner  produces less pollution  World supplies projected to last 60 more years?

Formed in 2 ways  Biogenic gas – created at shallow depths by the anaerobic decomposition of organic matter by bacteria, contains pure Methane  Decay process in landfills, landfill operators selling this gas as fuel. 1. Decreases energy waste 2. Reduces the release of methane 3. Profitable

 Thermogenic gas – Compression and heat deep underground 1. Organic matter turns to Kerogen, acts as a source for gas & oil. 2. Further heat & pressure breakdown kerogen into simpler hydrocarbon molecules  Most gas extracted commercially

Has Only Recently Been Widely Used  Versatile and clean burning, emits half as much carbon dioxide as coal and two-thirds as much as oil  Shipped long distances in tankers  Deposits are greatest in Russia & Middle East  Russia & US lead in gas production and consumption

Extracting Gas  Horsehead pump moves a rod in and out of a shaft, creating pressure to pull both natural gas and crude oil to the surface.  Fracturing technique pumps salt water under high pressures into rocks to crack them. Sand or glass beads are inserted to hold the cracks open once the water is withdrawn.

Offshore Drilling  Takes place in the seafloor on the continental shelves  Must withstand the forces of wind, waves, and ocean currents  Accounts for 25% of gas and oil in the US, primarily in the Gulf of Mexico and off the southern California Coast

Oil  Most used fuel since the 1960s  Accounts for 37% of the world’s commercial energy consumption.  Worldwide use has risen over 17% in the past decade.

Petroleum Formation  Crude oil, or petroleum, forms 1.3 – 3 km below the surface.  Mixture of hydrocarbon molecules forms sludgelike liquid.  Chain’s length affects it chemical properties, has consequences for human use.

Oil Consumption & Production

Location of Petroleum Oil Deposits  Geologists drill rock cores and conduct ground, air, and seismic surveys to map underground rock formations, and predict where fossil fuel deposits might lie.  Proven recoverable reserve – technologically and economically feasible to remove under current conditions.

We drill to extract oil  Exploratory Drilling – holes drilled are small, and descend to great depths., if enough oil is encountered, extraction begins.  Primary Extraction – Initial drilling and pumping (two-thirds of oil remains)  Secondary Extraction – Solvents, or underground rocks are flushed with water or steam.

Oil Drilling

Petroleum Products  Refining techniques, and chemical manufacturing expand use of petroleum.  From lubricants to plastics to fabrics to pharmaceuticals.  Concern for oil production to decline…..

Depleted half of oil reserves?  Have used up about 1.1 trillion barrels of oil, estimates hold that somewhat more than 1 trillion barrels remain.  Reserves-to-production ratio or R/P ratio – dividing the amount of total remaining reserves by the annual rate of production.  Current Levels  predict 1.2 trillion barrels would last about 40 more years!!!

Hubbert’s Peak

Consequences of Decreased Oil Production?  Globalized economy would collapse, economies would become intensely localized  Only feed a fraction of the world without petroleum based fertilizers and pesticides.  Rising oil prices will lead to conservation of energy and alternative energy sources.

Other Fossil Fuels  Oil sands can be mined and processed  Oil shale is abundant in the U.S. West  Methane hydrate shows potential  Downsides to other fossil fuels

Environmental Impacts of Fossil fuel Use

Impacts  Burning of fuels alter certain flux rates in Earth’s carbon cycle  Carbon Dioxide is a greenhouse gas, CO 2 warms the planet and drives global climate change.  Greatest environmental impact of fossil fuel use

Other impacts…  Some pollutants considered to be carcinogenic  Burning of Oil and coal  release pollutants that contribute to industrial and photochemical smog and to acidic deposition.  Gasoline combustion  releases pollutants that irritate the nose, throat, and lungs.  Pollute water  impacts on freshwater ecosystems, potential of oil spills in oceans.

Coal Mining affects the environment  Surface strip mining can destroy large swaths of habitat, & cause extensive soil erosion.  Cause chemical runoff into waterways  acid drainage.  Mountaintop removal  immense areas if habitat can be degraded or destroyed and creek beds can be polluted and clogged.

Oil & Gas extraction can alter the environment  Road networks must be constructed  Infrastructure for a drilling operation includes housing for workers, access roads, transport pipelines, waste piles for removed soil.  Extraction of salty groundwater can contaminate soil and kill vegetation.

 Mountaintop threatens welfare of nearby residents.  Subsurface mining raises health concerns for miners.  Inhaling coal dust, leads to respiratory diseases, including fatal black lung disease.

Effects of Prudhoe Bay  Tundra vegetation has not fully recovered from road production used 30 years ago.  Impact on Caribou  female caribou and their calves avoid all parts of Prudhoe Bay oil complex, reproductive rates is lower than other areas of Alaska.

Negative impacts of drilling in ANWR  Arctic National Wildlife Refuge is home to large mammals, grizzly bears, polar bears, wolves, Arctic foxes, and herds of caribou.  Scientists anticipate damage to vegetation and wildlife.

Political, Social, and Economic Impacts  Nations can become dependent on foreign energy  Oil supply and prices affect the economies of nations  Residents may or may not benefit from their fossil fuel reserves

Energy Conservation  Practice of reducing energy use to extend the lifetimes of our nonrenewable energy supplies.  Energy conservation has followed economic need  Personal choice and increased efficiency are 2 routes to conservation.  Both conservation and renewable energy are needed

Forms of Renewable Energy  Biomass Energy  Hydropower  Solar Energy  Wind Energy  Geothermal Energy  Tidal and wave energy