What are some nonrenewable energy sources?
Nuclear, coal, oil, natural gas, petroleum
**Nuclear is not renewable, but not a fossil fuel either
What are some renewable energy sources?
Biomass, hydroelectric, solar, wind, waves, geothermal
What is the equation for percent change?
abs(initial - final) / initial x 100 = %
What are the main issues with using wood/charcoal for fuel?
- Removal of wood can lead to soil degradation.
- Deforestation can decrease precipitation and CO2 sequestration
What are the types of coal? Which are the most valuable?
When peat dries out it becomes lignite, bituminous, and then anthracite. Because anthracite requires the most heat and pressure, it has the least amount of impurities and is valued the most. It has the highest heating capacity and a low sulfur content.
*Bituminous is the most commonly used. It has a high heating capacity, high sulfur content, but is cheaper than anthracite.
**Sulfuric emissions mixed with H20 vapor can cause acid deposition (acid rain), which has harmful effects on plants, animals, and infrastructure.
What is the cleanest burning fossil fuel?
Natural gas is the cleanest burning fossil fuel because it doesn’t release as many harmful emissions as other fossil fuels. It still produces carbon dioxide, but it just doesn’t release impurities like sulfur.
What is cogeneration?
Cogeneration occurs when a fuel source is used to generate both useful heat and electricity.
The separation of various components of crude oil in refineries is accomplished primarily by taking advantage of the differences in what?
The boiling points of the components.
An industry uses natural gas for manufacturing and uses the waste to heat and produce electricity. What is this process an example of?
Cogeneration.
What region is considered the world leader in petroleum resources?
The Middle East.
What is combustion?
Combustion is the process of burning fuel in the presence of oxygen to produce water and carbon dioxide.
What are the environmental problems associated with burning coal?
- Mining - destruction of habitat and resources used
- Pulverized coal - flammable and harmful to respiratory systems
- Heavy uses of water - can deplete habitat for species and water source
- Carbon dioxide - increases greenhouse effect globally
- Other pollutants - released into air and water
What are the environmental issues associated with coal/oil/gas extraction?
Coal:
- Surface Mining: removal of topsoil and habitat
- Subsurface Mining: destruction of habitat and dangerous
Oil: habitat destruction, potential for spills
Gas: destruction of habitat, water contamination, earthquakes
What is hydrologic fracturing or “fracking”?
A process of piping down into the ground to extract gas.
What are the environmental problems associated with hydrologic fracturing?
- Water contamination/Habitat destruction
- Fracking fluid contains volatile organic compounds (VOCs)
- Natural gas (often methane) may leak out
- May cause earthquakes
What are the advantages and disadvantages to nuclear fission?
Advantages:
- Low/No CH4 or CO2 emissions
- High power output
- Low cost after construction
- No mining for fossil fuels
- No primary/secondary air pollutants
Disadvantages:
- Long-lived hazardous nuclear waste/nuclear incidents
- Thermal pollution
- Very high cost
- Mining for construction and Uranium
- Non-renewable resource
What happens to nuclear waste?
Nuclear waste must be stored due to its radioactive properties. However, there is no designated spot for this waste to be relocated to, so it is stored on site.
What is the first law of thermodynamics?
Energy cannot be created or destroyed.
What are the positive and negative consequences for using biomass as an energy source?
Positive:
- Easily accessible
- Relatively inexpensive
- Used for heating and cooking
Negative:
- Air pollutants: carbon monoxide, nitrogen oxides, particulates, and volatile organic compounds
- Typically burned indoors, intensifying health effects of pollutants
- Overharvesting trees for fuelwood results in deforestation
What is biomass used for?
Biomass is a heat source, but is NOT a source for electricity.
What are biofuels?
Liquid fuels made from plant matter that can be used as substitutes for conventional petroleum products (gasoline and diesel)
*Ethanol is a replacement for gasoline and biodiesel is a replacement for diesel
What are the positive and negative consequences of using biofuels as an energy source?
Positive:
- Combustion is carbon neutral
- Potentially renewable
- Can be produced domestically
Negative:
- Net energy is low
- Harvesting crops for ethanol has the potential for increased fossil fuels in harvest, increased deforestation, and reduction in fertility of agricultural land
What are the different types of solar energy?
Photovoltaic (PV) Cells: Transforms sunlight directly into electricity
Active Solar: Uses mechanical and electric equipment to transfer solar heated liquid to transfer heat or to create electricity
Passive Solar: Heat is directly absorbed from the sun without mechanical or electric equipment
What are the positive and negative consequences of photovoltaics?
Positive:
- Generation of electricity
- Can reduce habitat destruction depending on installation placement
- Large and small-scale applications
Negative:
- Use is limited by the availability of sunlight
- Limited lifespan of nonrenewable PV cells
- Expensive
- Solar farms may negatively impact fragile desert ecosystems
