Fossil fuels (notes)

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NapierC ENVS 3100 Fall2021
Sustainability topic lecture

Fossil Fuels

Overview
 Formed from living organisms from earlier geologic eras
 80% of US energy from fossil fuels
 Reserves: fossil fuels masses that can be economically accessed
 Conventional (easy to obtain) vs. unconventional (difficult to obtain)
 Natural gas most common energy source in Georgia


Oil
 Formed within porous rocks (limestone, sandstone etc) surrounded by nonporous
rocks
 Extracted by drilling/pumping -> pressure causes oil to rise -> pumped by secondary
extraction OR tertiary extraction
 Hydraulic fracturing: extraction from unconventional reservoirs
 Chemicals/water etc injected into rock -> pressure causes fissures so gas flows out ->
methane and flowback water recovered
 Environmental impacts
o Acid rain
o Water contamination
o Oil spills in the ocean


Natural gas
 Found with oil deposits and bound up in layers of shale
 Fracking = extraction method
 Distributed through pipe network
 Environmental impacts
o Hazardous spills
o Contamination of groundwater
o Increased water scarcity
o Destruction of ecosystems


Coal
 Extracted from underground and via mountaintop removal
 Second largest energy source in the US
 Environmental impacts
o Acid rain
o Increased CO2
o Plant particulates cause smog
o Contamination of air and water resources