jjr Power

Renewable Resources

Alternative energy resources that will never run out because they are replaced by nature with little help from humans.

Solar, Wind, Hydro, Geothermal

Renewable Energy Resources

CK12 20.4

​CK12 20.1 Energy Resources

LAW OF CONSERVATION OF ENERGY

FOR A CLOSED SYSTEM, THE TOTAL ENERGY REMAINS UNCHANGED.

20.2 Obtaining Energy Resources

• Sources of Energy

• Nonrenewable resources are resources that are used faster than they can be replaced by natural processes - fossil fuels, such as coal, oil and uranium.

• Renewable resources are resources that can be replaced by natural processes in a relatively short amount of time - solar energy, wind energy etc.

​CK12 - 20.3

Nonrenewable Energy Resources

• Fossil Fuels - coal, oil, and natural gas. They form over millions of years and the type of fossil fuel formed depends upon: type of organic matter, temperature and pressure, and the length of time it was buried.

CK12 20.6: Coal

• The first step of coal formation occurred when plants died. A few hundred million years ago.

• Bacteria, extreme temperatures, and pressure acted on the remains

• Eventually a brownish material, peat, formed.

• Peat can be used as fuel, however it produces a lot of smoke when burned.

• Over time, peat hardens into coal.

CK12 20.7 and 20.8: Oil and Natural Gas

• Oil and natural gas are less dense than the rock and sediment that surrounds it.

• So oil and natural gas rise to the surface, passing through small pores in rocks.

• Eventually it will reach a layer that it cannot pass through. They will form deposits here, with the less dense gas settling on top of the oil.

Oil and Natural Gas

• Oil and natural gas form from different types of organisms than coal. They are formed from marine plankton that fell to the ocean floor.

• Bacteria decomposed the orgainc matter, and pressure and extreme temperatures acted on the sediment.

• During this process, thick, liquid oil formed. With enouth temperature and pressure, natural gas formed.

CK12 - 20.9 Advantages of Fossil Fuels

• The process of turning fossil fuels' chemical energy into electric energy is quite straight-forward and easy.

• Fossil Fuels are relatively inexpensive and easy to transport.

Disadvantages of Fossil Fuels

• Limited supply: Fossil fuels are nonrenewable, we'll run out eventually. Scientists predict that known oil reserves will last another 50 years at most.

• Habitat Disruption: Obtaining fossil fuels disturbs then environment. Mines disturb forest habitats, large batches of oil are routinely spilled into the ocean by large companies.

Disadvantages of Fossil Fuels

• Pollution: run off from coal mines can pollute soil and water.

• Burning fossil fuels releases chemicals into the atmosphere.

• Chemicals can react with water and cause acid rain.

CK12 - 20.10 Nuclear Energy

• Atoms are too small to see with just our eyes. However, they can release huge amounts of energy. Energy released from atomic reactions, is called nuclear energy.

Nuclear Fission

• Uranium atoms are placed into fuel rods. Neutrons are aimed at the rods and hit the Uranium atoms.

• Each atom splits and releases 2-3 other neutrons and thermal energy. The released atoms carry on a chain reaction.

• Countless split atoms release large amounts of thermal energy, this energy heats the water and changes it to steam.

• The steam turns a turbine connected to a generator, this produces electricity.

Advantages and Disadvantages of Nuclear Energy

• Advantages: only requires small amounts of uranium to produce large amount of energy. A well-run nuclear power plant won't pollute the air, soil or water.

• Disadvantages: Uranium isn't renewable. The chain reaction can get out of hand if not closely monitored. Radioactive substances can contaminate the environment. Radioactive waste materials remain dangerous for thousands of years.

Managing Nonrenewable Energy Resources

• Mined land must be reclaimed. Reclamation is a process in which mined land is recovered with soil and replanted with vegetation.

• The Clean Air Act in the US limits the amount off pollutants companies can release into the air.

• Stop vampire energy, the energy used by appliances plugged in 24 hours a day, like TV's, washing machines, microwaves etc. These appliances consume about 5% of energy used each year.

Guiding Questions & Standard

• What are renewable energy resources?

• How do renewable energy resources reduce human reliance on other natural resources?

CK12 20.11: Solar Energy

• Passive Solar Power

• Active Solar Power

• Benefits: Sunlight is free,

• Costs: can be expensive, battery technology not advanced enough, cloudy days

Hydroelectric Power

• Gravity pulls water down hill and can be used to generate electricity.

• Water spins a turbine, which generates electricity.

• Benefits: generates electricity and is controllable.

• Costs: disrupts natural flow of river and impacts natural processes, alters natural habitats, expensive to build

Wind Energy

• A land-based turbine that spins in the wind.

• Benefits: wind is free.

• Costs: $$, can threaten birds and spoil scenery, requires great amounts of land, parts of turbine are nonrenewable.

Geothermal Energy & Bioenergy Resources

• Dig deep into Earth and use the heat to warm water - creates steam which spins a turbine and generates electricity.

• Biomass (wood, grass, plant-based materials) can be burned to produce heat and light.

• Ethanol and other biodiesel technology is being explored.

What is Geothermal Energy?

● It is an internal energy beneath the Earth's surface that is accessed or tapped to convert it into electricity to be used by the consumers.

● It is usually tapped in near areas of volcanic origin.

There are three (3) types of Geothermal Energy

• Low-Temperature – ranges from 20°C to 90°C geothermal water; used only for heating.

• Medium-temperature – ranges from 90°C to 160°C geothermal water; geothermal water in liquid form is used to heat another fluid, which vaporizes to drive the turbine of the generator.

• High-temperature – geothermal water above 160°C; water is vaporized and used directly to drive the turbine of the plant’s generator.

Here's what you need to take note of:

• Only Medium- to High-Temperature types are possible for tapping.

• Geothermal waters (heated water on groundwater or injected water) were used to generate steam.

• Very hot steam is used to drive the turbine; this generates mechanical energy to electrical energy.

• Used geothermal water is injected back for cycling geothermal energy.

AIR POLLUTION

Air pollution refers to the release of pollutants into the air that are detrimental to human health and the planet as a whole. Most air pollution comes from energy use and production.