Earth’s Resources

Renewable Resources Can be replenished over fairly short time spans such as months, years or decades –Ex: Plants, solar energy, wind, water

Nonrenewable Resource takes millions of years to form and accumulate –Ex: coal, copper, uranium, gold

What Are Fossil Fuels? Anything past living materials that are found in the rock that is mined out as an energy resource

Types of Nonrenewable Energy Resources Coal Oil Natural Gas Uranium and Plutonium Tar Sands and Oil Shale

Coal Coal is a fossil fuel formed from the decomposition of organic materials (plant and animal remains) that have been exposed to heat and pressure found in the earth. Coal is burned to produce electricity PROS High energy Cost of coal is low CONS Dirties fuel Releases CO 2, SO 2, NO x, as pollutants Destroys the land

PEATLIGNITE

BITUMINOUS ANTHRACITE

How is Coal extracted from the Earth? Surface Mining: Scoop ore off surface or earth. cheap safe for miners large environmental destruction

How is Coal extracted from the Earth? Underground Mining: Use of shafts to reach deeply buried ores. expensive dangerous to miners less environmental damage

How is Coal extracted from the Earth? Mountaintop Removal: entire mountaintops are blasted off in the Appalachian Mountains –Causes deforestation and mudslides –Pollutes the waterways

Oil Deposits of crude oil containing hydrocarbons are often trapped within the earth's crust Extracted by drilling a well Refined as a gasoline product for fuels PROS High energy Low cost for fuel System is already in place to mine CONS Releases CO 2, SO 2, NO x, as pollutants Environmental problems (Gulf and Exxon Valdeze)

Prince William Sound

Natural Gas Natural gas is trapped in porous rock beneath the Earth above oil deposits Mixture 50–90% Methane Also Ethane, Propane, and Butane PROS Cleanest energy mined Mine inside the Earth – little land destroyed CONS Fracking – wells injecting water and gets into well water releases CO 2 into atmosphere

Uranium and Plutonium Nuclear reactors use mined Uranium to convert to Plutonium through fission (splitting of atoms) Reactors can be designed to convert 238 U into a fissionable isotope of plutonium, 239 Pu PROS Large fuel supply Low CO 2 emissions CONS Accidents – Japan and Chernobyl Reactors last only 40 years Expensive

Tar Sands and Oil Shale Tar Sand is a mixture of clay, sand, water and combustible bitumen (heavy oil with high sulfur content). Oil shales contain kerogen which can be extracted from crushed oil shales by heating them to yield a distillate called shale oil. PROS Alternative when oil is depleted Moderate energy CONS Destroys land when mined Releases CO 2, SO 2, NO x, as pollutants

Years left of Resources in the World CoalOilNatural Gas 300 Years35 to 50 Years 125 to 200 Years

What do you know about… Biofuels Geothermal Hydroelectric Power Hydrogen Fuel Cells Solar Tidal Power Wave Power Wind

Biofuels Uses plant material and animal waste to convert to a biofuel Types of Biomass/fuels Wood logs, Animal dung, Kelp, and Paper/cardboard Pros Tree farms can restore degraded lands Large potential supply Cons CO 2 emissions if harvested and not planted back Soil erosion, water pollution, and loss of habitat

ECU 35 – Biodiesel / Hybrid

ECU 51 – BRT Clean Diesel Hybrid

Geothermal Energy Energy is harnessed by tapping natural underground reservoirs of steam and hot water hot water pulled from the earth is used directly for heating and to turn turbines to generate electric power PROS Available 24/7 Little emissions of CO 2 and natural gas. CONS Only available near geological activity Habitat destruction when building it

rebasics_geothermal.html

The Geysers

Hydroelectric Water is stored behind a dam and released periodically by gravity. The falling water turns turbines which produce electricity. Pros Long life span No CO 2 emissions Flood control method Provides water for year round irrigation Cons Expensive Converts land to water habitat Danger of it collapsing Decreases fish spawning

Hydrogen Fuel Cells A device that converts chemical energy into electrical energy. Splitting water atoms to extract the hydrogen for energy use. PROS No CO 2 emissions Safe Low environmental impact CONS High cost Doesn’t last long when made New energy – not readily available

A typical hydrogen fuel cell

Solar Energy Uses energy from the Sun to produce energy Pros Free No CO 2 emissions Low air and water pollution Cons Need access to sun 60% of time Need a heat storage system Expensive system

Types of Solar Energy Passive system: Absorbs & stores heat from the sun directly within a structure Active system: Collectors absorb solar energy, a pump supplies part of a buildings heating or water heating needs.

Tidal Power Uses the force of water during a high tide to turn a turbine to create energy. East coast: two high tides Pros Know when daily high tides on the east coast No CO 2 emissions Cons Unreliable on west coast Expensive equipment

Tidal Dam Why is a large tidal range need to produce power?

Wave energy The motion of wind- driven waves at the ocean’s surface is converted into electricity. Pros No CO 2 emissions Works during day and night Cons Expensive Machines break down and corrode in water

Wind Energy Uses wind power to turn a turbine which creates energy in the next 50 years, wind power could meet up to 10% of the country’s demand for electricity Pros Highly efficient Low environmental impact No CO 2 emissions Quick construction Cons Need steady winds noise pollution Visual pollution damage/death to animals (birds)