Project 1: Eco Footprint Flashcards
cogeneration
the generation of electricity and other energy jointly, especially the utilization of the steam left over from electricity generation to produce heat.
ecological footprint
the impact of a person or community on the environment, expressed as the amount of land required to sustain their use of natural resources.
sustainability
avoidance of the depletion of natural resources in order to maintain an ecological balance.
bituminous coal
black coal having a relatively high volatile content. It burns with a characteristically bright smoky flame.
Contains the widest range of carbon content (45% to 86%),
mainly used as a fuel to generate electricity, though some is used as coking coal to produce steel.
The oldest and most abundant coal type found in the United States; contributes about 50% of all U.S. coal
Electric power
the rate at which electric energy is transferred to other forms of energy
Measured in Watts (W) or kiloWatts (kW)
Most energy companies measure electrical energy in kilowatt hours (kWh), or wattage used per hour (h).
1st Law of Thermodynamics
Law of Conservation of Energy
the total energy of an isolated system is constant; energy can be transformed from one form to another, but can be neither created nor destroyed.
entropy
scientific concept, as well as a measurable physical property that is most commonly associated with a state of disorder, randomness, or uncertainty.
2nd Law of Thermodynamics
Law of Entropy
Entropy predicts the direction of spontaneous processes, and determines whether they are irreversible or impossible, despite obeying the requirement of conservation of energy,
Equation for kiloWatt hours
kW x h = kWh
the major fossil fuels we use
Coal, oil, and natural gas, come from deposits of organic matter that were formed 100 million to 500 million years ago.
The energy in these fuels originally came from the sun and was converted to chemical energy through photosynthesis
These high-energy fuels were created when dead biological materials built up under layers of sediment and were exposed to heat and pressure over millions of years.
Major uses of the fossil fuels
Coal – 41% of global electricity is derived from burning coal, coal is required in steel making
Oil – gasoline for transportation, diesel oil, heating oil, petrochemical industry (plastics, chemicals, asphalt)
Natural gas – burned to generate electricity, residential heating and cooking, feedstock for plastics, transportation fuel.
Coal
A solid fuel formed from the remains of plant materials preserved 300 million to 400 million years ago.
There are four types/stages of coal
lignite
sub-bituminous
bituminous
anthracite
These stages are formed when peat, partly decomposed organic material, is compressed between layers of sediment.
Sub – bituminous coal
Lignite in which Hydrogen and oxygen has been driven off resulting in higher carbon content
Second lowest energy content, large quantities are found in thick beds near the surface, resulting in low mining cost and, correspondingly, lower prices
Lignite
Formed under least pressure and heat, but more moisture. Can contain recognizable plant structures. (brown coal)
As a result, lignite has a low carbon content (25% to 35%).
Anthracite:
Formed under the greatest pressure, high temps and low moisture. Has highest carbon content and highest heating value.
Rare in the U.S.
Scrubbers
Air pollution control devices that remove acidic gases and/or particulates from industrial exhaust streams and coal smokestacks
Wet scrubbers use a “scrubbing liquid” to trap pollutants
Dry scrubbers use dry reagents or electrical charge.
Electrostatic Precipitators
Filter particles from exhaust fumes by inducing an electrostatic charge in the particles and then attracting them to collecting plates of the opposite charge
Thermal Pollution due to burning coal
Coal burning power plants and industrial process that discharge warmer water into nearby cooler rivers can cause thermal pollution.
Warm water holds less dissolved oxygen than cooler water. (As temperatures rise fish and other aquatic species will struggle for oxygen)
Warmer water can speed up the metabolic rate of aquatic organisms leading them to deplete their food resources.
Natural Gas
methane (CH4), ethane, propane, and butane.
Mostly extracted in association with petroleum, but direct drilling for natural gas has recently been explored.
Methane is also released by anaerobic microbes in landfills, swamps, and cow’s stomach (rumen)
One way of extracting oil and natural gas is through fracking.
Fracking
the process of injecting liquid at high pressure into subterranean rocks, boreholes, etc. so as to force open existing fissures and extract oil or gas.
Environmental concerns over fracking
Requires too much water Groundwater contamination Surface water contamination Methane gas leaks (greenhouse gas 23 times as potent as CO2) Earthquakes
Why natural gas is considered a “bridge” fuel
Burning Natural gas emits 50% less CO2 into the atmosphere when compared to coal burning to produce the same amount of energy
Burning natural gas releases less impurities (mercury, SO2, NOx, Particulate matter)
Some consider it a “bridge” fuel as we transition to renewables
Petroleum
Fluid mix of hydrocarbons, water, and sulfur that occurs in underground deposits. Petroleum removed from the ground is known as crude oil
Formed when the remains of ocean-dwelling phytoplankton (microscopic algae) 50 million - 150 million years ago
Petroleum fills the pore spaces in rock over millions of years and migrates up to the highest point of the porous rock, where it is trapped by non-porous rock.
Fractional distillation of crude oil
Crude oil is heated allowing hydrocarbons of different molecular weights to be separated according to their boiling points.