Alternative energy Flashcards
What are some examples of energy sources that did not originate from the sun?
geothermal energy
sun energy
wind energy
hydropower
What makes an energy source “renewable”?
it can be
renewed
reused
remade
regnerated
it comes from a natural resource that can replenish itself, like wind, solar, or water. Renewable energy sources are usually low- or zero-carbon, and they can have many environmental and economic benefits.
What makes an energy source “clean”?
when it produces minimal to no greenhouse gas emissions or other pollutants during its generation process
What is one energy source that is clean, but not renewable?
Nuclear energy is considered a clean energy source,
but it is not renewable because the uranium fuel used has a limit or end and cannot be replenished quickly enough to be considered renewable.
How about a source that is not clean, but renewable?
biomass;
while it can be replenished through plant growth, burning biomass for energy can still release significant amounts of carbon dioxide
How does nuclear energy work to generate electricity?
Nuclear Fission: In a nuclear reactor, atoms of uranium or other fuels are split apart in a controlled reaction. When these atoms split, they release a huge amount of energy in the form of heat.
Heating Water: The heat produced by fission is used to heat water. The water is turned into steam.
Steam Drives Turbine: The steam is directed to a turbine, which is a large spinning wheel. The force of the steam makes the turbine spin.
Turbine Spins Generator: The turbine is connected to a generator. When the turbine spins, it turns the generator’s rotor.
Electricity Production: As the rotor turns, it generates electricity through electromagnetic induction, which is then sent to power lines.
Cooling: After the steam passes through the turbine, it is cooled down and turned back into water to be reused in the system.
pros and cons of nuclear energy
Pro - saves lives, toxic by products are stored, cost effective, low ghg emissions
Cons - nuclear weapons, nuclear waste and pollution, accidents and disasters
What are some of the challenges of implementing renewable energy sources?
Intermittency
Cost
Space
Reliability
Public Acceptance
How might you surmount some of those challenges of implementing renewable energy sources?
As renewable technologies improve and scale up, their costs are likely to drop, making them more affordable over time.
engage with local communities early in the planning process to address concerns and gain support for projects.
Explain NIMBYism as one of the challenges.
“Not In My Back Yard” and refers to the opposition some people have to projects or developments that they don’t want near their homes, even if they support the idea in general.
explain intermittency
refers to the fact that some renewable energy sources, like solar and wind, aren’t always available. For example, solar energy only works when the sun is shining, and wind energy only works when the wind is blowing. This means the energy production can be unpredictable or “intermittent.”
what sources are intermittent? What aren’t?
Are - solar panels, wind turbines,
Arent - coal, natural gas, nuclear power
Solar energy pro and cons
pro -
- Renewable and abundant.
Reduces electricity bills.
Low environmental impact during operation.
Can be installed on rooftops (doesn’t require large land areas).
Con
- Intermittent (depends on sunlight).
Requires large battery storage for nighttime use.
High initial installation costs.
Efficiency can be affected by weather or location.
Wind Energy pros and cons
Pros:
Renewable and clean.
Can produce large amounts of energy.
Land can still be used for farming or other activities around wind turbines.
Cons:
Intermittent (depends on wind conditions).
Can be noisy and visually disruptive to local communities (NIMBYism).
Threat to birds and bats.
Requires a lot of land space for large wind farms.
hydropower pros and cons
Pros:
Reliable and consistent
Can generate large amounts of electricity.
Useful for grid stability (can provide backup power quickly).
Cons:
Environmental impact (disrupts ecosystems and local wildlife).
High initial construction costs.
Requires large bodies of water (may lead to displacement of communities or wildlife).
Vulnerable to droughts and water level changes.
Geothermal pros and cons
Pros
Reliable and consistent (non-intermittent).
Low environmental impact.
Can provide heating and cooling as well as electricity.
Cons
Only feasible in certain locations (close to tectonic plate boundaries or geothermal hotspots).
High initial installation costs.
Limited availability depending on location.
Biomass pros and cons
Pros:
Can use organic waste materials (like wood, agricultural residues, or even garbage).
Can reduce waste in landfills.
Can produce electricity and heat.
Cons:
Still produces some emissions (though less than fossil fuels).
Requires land and resources to grow the biomass.
Can contribute to deforestation if not managed properly.
May compete with food production in some cases.
Why does hydroelectricity represent a wicked problem?
enviro impact
- clean renewable energy source
- but can effect the ecosystems and animals
Economic
- expensive
Conflicting Stakeholders
- differing opinions of the townspeople, companies and the government
How is electricity generated?
energy source needs to be found
the energy source is used to turn a turbine or similar device
The turbine is connected to a generator and makes electricity
the electricity produced is then sent through power lines (high-voltage transmission lines) to reach homes, businesses, and other users.
the high-voltage electricity is stepped down to a lower voltage at substations, and then it’s delivered to homes and businesses.
What is the average electricity generation plant efficiency and how can you connect this to the second law of thermodynamics?
fossil fuel plants - 33 - 45
nuclear plants - 33 - 37
Renewable energy plants, like wind and solar, have near 100% efficiency in terms of converting their specific resource (wind or sunlight) into electricity
in any energy conversion process, some energy is lost as waste heat, and no process can be 100% efficient
when converting heat (like from burning fuel) into mechanical energy to generate electricity, some of the energy is always lost and cannot be fully used to do work.
second law of thermodynamics
when energy is converted its ability to do work diminishes
how does hydropower work
Water Flow: Water from a river or reservoir is directed toward a dam or turbine.
Turbine Movement: The flowing water pushes against blades on a turbine, making it spin.
Generator: The turbine is connected to a generator. As the turbine spins, it causes the generator to produce electricity.
Transmission: The electricity is sent through power lines to homes and businesses.
how does geothermal work
Heat from the Earth: The Earth’s core is very hot, and this heat rises toward the surface. In some areas, this heat is closer to the surface, like in hot springs or volcanic regions.
Hot Water or Steam: Wells are drilled into the ground to reach this hot water or steam.
Turbine Movement: The steam is brought to the surface, where it can be used to spin a turbine.
Generator: The turbine is connected to a generator, which produces electricity as it spins.
Energy Use: The electricity is then sent through power lines to homes and businesses, or the hot water can be used for heating directly.
how does solar energy work
Solar Panels: Solar panels made of special materials (like silicon) are placed on rooftops or in sunny areas.
Absorbing Sunlight: When sunlight hits the solar panels, the material inside the panels absorbs the energy.
Electricity Generation: The absorbed sunlight creates an electric current by exciting the electrons in the material, which then flow through the panel and into wires.
Powering Devices: This electricity is sent to your home or building, where it can be used to power lights, appliances, and other devices.
