7.1 Energy Transformers Flashcards
What is the purpose of the EnerGuide label?
To help consumers make informed choices about the energy consumption of household appliances.
What does the EnerGuide label estimate?
The amount of electrical energy (in kilowatt-hours) an appliance will use in one year.
What is geothermal generation?
The use of heat found in the Earth to create steam for energy production.
List two advantages of geothermal generation
- Always has available heat deep in the Earth
- Pollution free
What is one disadvantage of geothermal generation?
Needs to be built near hot springs or where magma is close to the surface.
What does photovoltaic generation use?
The sun’s energy.
List two advantages of photovoltaic generation
- Sun is free and renewable
- Can be installed anywhere with sunlight
What is one disadvantage of photovoltaic generation?
Very expensive to install.
What is wind generation?
The use of wind to generate electricity.
List two advantages of wind generation
- Wind is free
- Wind turbines are less expensive than other generating plants
What is one disadvantage of wind generation?
Can kill migrating birds.
What is hydroelectric generation?
Using moving water to turn turbines to generate electricity.
List two advantages of hydroelectric generation
- No pollution
- Renewable
What is one disadvantage of hydroelectric generation?
Large areas are flooded.
How is nuclear energy produced?
By splitting uranium atoms, releasing energy that boils water to create steam.
List two advantages of nuclear energy
- No air pollution
- No greenhouse gases (CO2)
What is one disadvantage of nuclear energy?
Waste products are radioactive.
What are fossil fuels?
Coal, oil, or natural gas burned for energy.
List two advantages of fossil fuels
- Easy to use and less expensive
- Generating stations are already built
What is one disadvantage of fossil fuels?
Not a renewable resource.
What is thermal generation of electricity?
Uses steam to spin turbines.
What units measure electrical power?
Watts (W) for power and Joules (J) for energy.
What is the common unit for energy usage on electricity bills?
Kilowatt-hours (kWh).
Calculate the percent efficiency of a light bulb that uses 780 J of input energy to produce 31 J of light energy.
4% efficiency.
Fill in the blank: Energy Efficiency is a measure of how much useful energy an electrical device produces compared with the amount of _______.
energy that was supplied to the device.
What is the formula to calculate energy consumed?
E consumed = P X t.
Fill in the blank: To calculate the cost of using an electrical device, you multiply the energy consumed by the _______.
electricity rate.
What happens to high voltage electricity when it is transported over long distances?
It reduces energy loss as heat.
What is Alternating Current (AC)?
Current in which electrons move back and forth in a circuit.
What is one learning goal regarding energy consumption?
Determine Energy Consumption of appliances in our homes.
