Flashcards in Environment/Nature V Deck (38)
How does the first law of thermodynamics relate to the food chain?
None of the organisms devouring each other up and down the trophic structure creates new energy.
- it just passes along energy that came from somewhere else. And where is that?
- if you the links back, it came from the sun.
What is the second law of thermodynamics?
Energy conversions are never 100% efficient: whenever energy is transformed into work, some is always dissipated, or wasted.
How does the second law relate to the food chain?
Ecological efficiency (aka "food chain efficiency")
- the percentage of usable energy captured at each level of consumption.
- the amount of energy consumed from the original solar source diminishes as it goes up the food chain (tertiary consumers get less of the original energy).
What is the first law of thermodynamics?
Energy is neither created nor destroyed. It just changes from one form to another.
Organism that eats both plants and animals.
In a general sense, what is fracking?
- Fracking is slang for "hydrofracking" or "hydraulic fracturing".
It is a catch all term for two drilling techniques frequently used together:
- horizontal drilling
- hydraulic fracturing
(aka directional drilling)
- energy companies do this to drill through long, narrow shale formations
- Uses drill bits that bend
- allows energy companies to drill vertically (up and down) and then laterally (left to right)
- drilling technique in which a "slurry" of fluids is injected underground at very high pressure to crack open dense shale rock (this allows oil or gas to flow to the surface, where it is captured for our use).
The fluids injected include:
- chemicals (antifreeze, hydrochloric acid)
- A combustible mineral substance made of carbonized vegetable matter.
- It's a fossil fuel.
- Used as fuel.
(It is plentiful and cheap)
- large leafy plants
- phytoplankton (algae)
When were fossil fuels formed?
300 million years ago, during the Carboniferous period
- the Carboniferous era predates the dinosaurs and is at the tail end of the Paleozoic era
What happened when creatures that became fossil fuel died?
- They sank to the bottom of swamps and oceans and became "peat".
- they then cooked in the earth for millions of years till they became hydrocarbon energy.
What is coal used for?
To fuel power plants
To generate electricity
Which countries are the main drivers of increased global coal use?
India and China.
China's domestic coal industry produces more primary energy than oil from the Middle East does.
Oil is a fossil fuel.
- it was created more than 300 million years ago.
- diatoms are sea creatures (algae) that convert sunlight into stored energy.
- they died and were trapped under rocks at the bottom of the ocean.
- the rock compressed the diatom, trapping the energy in their bodies.
- they eventually became hydrocarbon energy (an organic chemical compound composed of hydrogen and carbon atoms)
What is the world's most popular energy source?
It represents 33% of global energy use.
What is the current global oil demand?
Roughly 98 million barrels a day
Barrels (as in barrels of oil)
Commodities that oil refineries break hydrocarbons down into. Includes:
- diesel fuel
- aviation fuel
- heating oil
Oil is also used to produce:
Where does gas come from?
How much do Americans use?
Gas is the main product produced from crude oil.
- we use around 300 million gallons per day.
- a chemical compound made of one carbon atom and four hydrogen atoms.
A fossil fuel made of methane.
- lighter than air
- found near petroleum deposits deep underground
- highly flammable
A cubic foot
How is natural gas measured?
- by cubic foot
Natural gas byproducts
"wet" natural gas contains liquid hydrocarbon and gases like butane and propane (which must be removed).
Once it is removed the gas is "dry" and is sellable
What is natural gas used for?
- Electricity generation
- to fuel power plants
- to power trucks
- commercial and industrial uses
Why is natural gas called a "bridge fuel"?
- It emits less CO2 than other fossil fuels.
- it requires less processing
- it will realistically take decades and billions of dollars to scale up the capacity of renewable energy plants.
- natural gas will help ease the transition
How long will it take to switch to renewable energy?
It will take:
- billions of dollars
To scale up the capacity of renewable energy plants.
What is "unconventional" oil?
Oil acquired by means other than drilling a traditional borehole in the ground (vertical drilling).
- tar sands
- natural gas
(aka "oil sands")
Deposits of heavy oil so viscous they do not flow.
- extracted by injecting hot steam into deposits (makes the tar more liquid)
- environmentally destructive and only makes sense if oil prices are high.
- Athabaskan oil sands in Alberta is the biggest.
Natural gas trapped in deposits in shale rock formations.
- accessed through vertical drilling and fracking.
What are the technical names for natural gas?
- "Technically recoverable unconventional gas"
- shale gas
- tight sands
- coal bed methane
Heavy, viscous crude deposits.
- cannot be refined conventionally
- contain a lot of sulfur
Coal bed methane
Natural gas extracted from coal beds.
Process used to produce "syngas" (synthesis gas).
- CO2 can be removed from this gas, but it is expensive to make.
Liquid fuels converted from:
- natural gas
- bio mass
Organic matter, especially plant matter, that can be converted to fuel, and is therefore regarded as a potential fuel source.