Alternative Energy Study Guide
7 types of renewable energy to support commercial sustainability
- Bioenergy
- Geothermal
- Hydroelectric
- Hydrogen
- Ocean
- Solar
- Wind
- Nuclear
Vocabulary and Terms:
Electricity:
1a:a fundamental form of energy observable in positive and negative forms that occurs naturally (as in lightning) or is produced (as in a generator) and that is expressed in terms of the movement and interaction ofelectrons
b:electriccurrent or power
Electric current (or electricity) flows when a magnet is moved inside a coil of wire.
An electric power plant uses a turbine (steam, gas combustion, water and wind) to drive a generator (a magnet moved inside a coil of wire) to create an electrical current.
95% of all U.S. electricity generation was from steam turbines, in 2015.
Electricity in NOT easily stored.
Electricity flows through a grid. The grids are connected in limited ways. TX does NOT connect to NY. (‘Forget about it.’)
Regulatory mandate: laws (local, state, or federal)
Three types of sustainability: economic, environmental, social
Sustainable-the wise use of resources for future generations
Unsustainable/non-renewable energy-a finite energy source i.e. fossil fuels
Fossil Fuels: natural gas, coal, oil
Biomass: organic matter coming from recently living plants or animals (i.e. wood, manure, prairie grass, decomposing matter, capturing and using methane gas)
Bioenergy: renewable energy derived from biomass to create heat and electricity or liquid fuels (i.e. ethanol and biodiesel)
Bioenergy is not a greenhouse gas win—because it generates about the same amount of CO2 as fossil fuels.
Biomass can be used for transportation (fleet vehicles can use ethanol or biodiesel)
Factories can produce steam captured by a turbine to generate electricity.
Farms can convert waste (manure) from livestock into electricity using smaller, modular systems.
Towns (municipalities) can tap methane gas created (by the anaerobic digestion of organic waste) in landfills to use as fuel for generating electricity.
2. Geothermal-geo (earth) thermal (heat) heat of the earth (two types: close to the surface or from heated rock and reservoirs of hot water miles beneath our feet.
Can be used commercially and residentially
power plants
residential environment (heat pump—which produces both heat and air conditioning)
grow greenhouse plants
heating water at fish farms
helping in industrial processes (pasteurizing milk)
Works by reducing the delta (amount of difference) between the earth’s constant temperature, and the outside atmospheric temperature.
Earth’s temperature is always 56 degrees Fahrenheit
3. Hydroelectric: harnessing the kinetic energy of water and flowing rivers
Hydro-water
Kinetic-of or relating to the motion of material bodies and the forces and energy associated therewith
Reservoir-:a place where something is kept in store: such as
a:an artificial lake where water is collected and kept in quantity for use
Dams store water in a reservoir. When water is released it flows through turbines to produce electricity (pumped-storage hydropower)
Waterwheels moved water to operate gristmills (ground grain) and sawmills in early America
Low demand—little electricity is needed by the municipality
High demand—much electricity is needed by the municipality (think August—hazy, hot and humid—and how much electricity is requested for air conditioners)
municipality:a primarily urban political unit having corporate (seecorporate1a) status and usually powers of self-government(i.e Elections were held in themunicipality.
Run of the River Hydropower—funnels a portion of river flow through a channel (does not require a dam)
Hoover Dam-dam 726 feet (221 meters) high in the Colorado River between Nevada and Arizona that was completed in 1936
Silt-fine dirt (often picked up from river banks from one place, then dropped another place)
Negatives with Hydropower: location. You must be near running water to use it.
Silt build up behind dams-creates a toxic waste hazard when the dam needs to be torn down.
4. Hydrogen
Hydrogen does not occur naturally as a gas on the earth.
Hydrogen is high in energy, yet produces little or no pollution when burned.
Byproducts of hydrogen energy is water and heat.
Hydrogen energy is expensive and not sustainable (at this time).
There are a few hundred hydrogen-powered vehicles operating in the US. This could rise if more refueling stations are built.
Hydrogen power could be used in: large fuel cells providing emergency electricity for buildings and remote locations and marine vessels.
5. Ocean
Two types: thermal energy from the sun’s heat, and mechanical energy from the motion of tides and waves.
Thermal energy-relies on warm water temperatures.
Mechanical energy-relies on harnessing the ebbs and flows of tides
There are other experimental types: salinity, ocean current, ocean winds.
Commercial applications are limited by geography and regulatory guidelines.
At this time, ocean energy would only be supplemental to municipalities.
6. Solar
Two types:
Solar energy can be created without the use of a turbine. PV (photovoltaic) systems use solar cells to convert light into electricity.
Solar hot water systems heat water in tubes which become steam and run a turbine.
7. Wind
Wind (can be considered a form of solar energy—because winds are caused by uneven heating and cooling of the atmosphere by the sun).
Wind flow can be captured by turbines and converted into electricity.
Uses: commercial wind farms, residential windmills can be used to pump wells
Frequently wind power is a supplemental energy.
Wind power is naturally inconsistent.
Dominion Energy does have wind as one of its green energy programs.
- Nuclear
Nuclear fission-a neutron collides with a uranium atom and SPLITS it, releasing energy in the form of heat and radiation. This occurs over and over in a process called a nuclear chain reaction.
Nuclear fusion-atoms are combined or FUSED together to form a larger atom.
Fusion is the source of energy in the sun and stars.
Fission uses uranium with is a limited resource because it is mined.
20% of the total U.S. electricity in 2015.
Front end steps: prepare uranium to use in nuclear reactors.
Back end steps: manage, prepare, and dispose of highly radioactive spent nuclear fuel. Yucca Mountain WAS a U.S. storage space, but it is not in use.
Fuel assembly, and fuel rods have radioactive tips.
These are both problems with the sustainability of nuclear energy.
REC-Renewable Energy Certificates-sold on the open market for green energy. Using Energy Certificates is a sustainable social choice.
Dominion Energy-our power company
Dominion Energy does not make a profit from their green energy program.
As a commercial or residential customer, you pay Dominion Energy extra money to use the amount of ‘green energy’ you want. You could cover all the energy your use, or only a portion (50%).
Dominion Energy Green Power REC’s come from wind, solar and biomass facilities in the mid-Atlantic and Southeastern regions.
78% Wind; 21% Biomass; 1% Solar. Green power comes from PA, NJ, VA and MO (Missouri)--2013.
There are 850 voluntary green pricing programs likek Dominion Energy Green Power offered by utilities across the country.
1 Tracy-Alternative Energy Study Guide