6.5 Fossil Fuels

Question 1

IMPORTANT NOTE(THREE STEPS TO GENERATE ELECTRICITY)

Answer 1

These steps of electricity gen. are the same, no matter what you’re burning to produce the initial heat
Heat →Water into Steam → Steam turns a turbine → Turbine powers generator → Generator produces electricity

Question 2

Environmental Consequence of Coal

Answer 2

Habitat destruction to clear land for mining

Question 3

Environmental Consequence of Coal

Answer 3

Releases more CO2 than any other FF when burned for electricity gen.

Question 4

Environmental Consequence of Coal

Answer 4

Produces pollutants: Releases PM (soot, ash) which can irritate respiratory tracts of humans/animals
Produces toxic ash contaminated with lead, mercury, and arsenic
Taken to landfills or stored in ash ponds; both can leak into ground/surface waters, or into soil
Releases SOx & NOx (sulfur and nitrogen oxides) which irritate resp. systems, and contribute to smog and acid precipitation

Question 5

How efficient are Coal and Natural Gas at generating electricity

Answer 5

Coal is ~30% efficient
Nat. Gas is ~60% efficient
***Much of the energy “lost” or not converted into electricity escapes as heat

Question 6

What is Cogeneration

Answer 6

Cogeneration: when the heat produced from electricity generation is used to provide heat (air & hot water) to a building;

Question 7

What is CHP and the percentage of how more efficient it is than Carbon and Natural Gas

Answer 7

CHP (Combined Heat and Power) systems are close to 90% efficient (much better than coal/NG alone)

Question 8

Why is extracting oil from tar sands bad

Answer 8

Lots of water needs to be heated(requiring energy) to create steam that’s piped down into the tar sand to melt the bitumen into a liquid that can flow up a pipe
Lots more water is used to separate the oil from all of the impurities (sand, clay) at the refinery

Question 9

Environmental Consequences:
Tar Sands

Answer 9

Habitat destruction from clearing lands for roads, drilling to reach deposits.
Ground or surface water depletion as a lot of water s needed to create steam, and separate the impurities
Tailing ponds(holes for dug for storing wastewater, overflow, run into surface water, leach into groundwater(Water contamination). Carbon Dioxide released from machinery

Question 10

Environmental Consequences:
Crude Oil/Petroleum

Answer 10

Spills in water from tanker ships or pipeline breaking–>crude oil covers sun–>clogging fish gills, suffocating ocean animals.
Spills on land—>toxic to plant roots, surface or groundwater contamination (with hydrocarbons/crude oil)
Habitat loss or fragmentation when land is cleared for roads, drilling equipment, pipelines

Question 11

What is flowback water

Answer 11

Flowback water (used fracking fluid) flows back out well & is collected and stored in containers or ponds nearby

Question 12

Environmental Consequences:
Fracking

Answer 12

Possibility of well leaking & contaminating groundwater with fracking fluid (salt, detergents, acids) or hydrocarbons
Ponds can overflow or leach into ground & contaminate surface or ground waters with fracking fluid (salt, detergents, acids)

Can be toxic to plants & animals that rely on these water sources
Hab. loss/fragment
⛰️ CH4 (GHG) release
Increased seismic activity (earthquakes) linked with wastewater injection wells (storing fracking fluid deep underground)
Depletion of ground or surface waters nearby (as they’re drawn from for fracking fluid)