Energy sources are the means by which we generate power to meet our needs.
They power things like cars, factories, and homes.
They can be renewable or non-renewable.
Because burning fossil fuels releases pollution, it’s important to find cleaner energy sources for a healthier planet.
Fossil Fuels
Fossil fuels are formed from ancient plants and animals that lived millions of years ago.
They include coal, oil, and natural gas.
When we burn these fuels, they release energy that we can use to power cars, factories, and homes.
Burning fossil fuels also releases pollution, so cleaner energy sources are important.
Renewable Energy Sources
Renewable energy sources are those that can be restored or replaced by natural processes.
Solar Energy
The sun gives off light and heat energy.
Solar panels capture the sun’s energy and turn it into electricity.
Analogy: It’s like using the sun’s power.
Wind Energy
The wind blows around us, and wind turbines capture this energy and convert it into electricity.
Analogy: It’s like a big fan that creates electricity when it spins.
Hydropower
Water can create energy by collecting water in dams.
When water flows through turbines, it turns into electricity.
Analogy: It’s like using the power of flowing water.
Geothermal Energy
Deep inside the Earth there is heat from hot rocks.
This heat can be used to make steam and turn it into electricity.
Analogy: It’s like using Earth’s own heat.
Biomass
Biomass is made from organic materials like wood, plants, or waste.
These materials can be burned to release energy or turned into a gas called biogas.
Analogy: It’s like using nature’s leftovers.
Energy Conservation and Clean Energy
It’s important to use energy wisely and consider environmental impact.
We are finding new ways to produce clean and renewable energy for a healthier planet.
Types of Energy
Renewable Source of Energy
Definition: energy that can be restored or replaced by natural processes.
Solar Energy: arrives from the sun by electromagnetic radiation; can be used directly for heat and converted to electricity for other uses; nearly unlimited, renewable and largely non-polluting.
Solar Energy (continued)
Solar energy arrives from the sun by electromagnetic radiation.
It can be used directly for heat and converted to electricity for other uses.
It is nearly unlimited, renewable, and largely non-polluting.
Wind Energy
Uses the wind current to create electricity using windmills.
Geothermal Energy
The heat that causes the temperature to increase with depth in the Earth; responsible for melting mantle rocks to form magma.
Hydroelectric Energy
Requires geologic knowledge to ensure dams are built in areas where they will not collapse and harm human populations.
Parts of a Hydroelectric Plant
Component Functions
Raises the water level of the river to create falling water (provides potential energy).
Controls the flow of water.
Stores energy in the form of stored water.
The force of the flowing water pushing against the turbine blades causes the turbine to spin.
The turbine converts kinetic energy of flowing water into mechanical energy.
Generator Connection and Transmission
The turbine is connected to the generator by shafts and possibly gears so that when the turbine spins, the generator spins as well.
The generator converts mechanical energy from the turbine into electric energy.
Electricity is conducted from the hydropower plant to homes and businesses.
Environmental Impact of Hydroelectric Power Plants
It destroys forests, wildlife habitat, agricultural land, and scenic lands.
Non-Renewable Energy
Definition: energy that cannot be readily replaced by natural processes.
Formation of Petroleum
Steps
Organic matter from organisms must be produced in great abundance.
This organic matter must be buried rapidly before oxidation takes place.
Slow chemical reactions transform the organic material into the hydrocarbon found in petroleum.
Environmental Impact of Petroleum
When burned, petroleum products emit carbon dioxide, carbon monoxide, and other toxins, all of which have a negative effect on the environment.