Energy Sources

Science

with Mr. Nahm

Hydro power

• Early source of power water wheel

• The movement of water causes the water wheel to rotate along with the wheel’s axle.

• The spinning axle can power various different machines.

Hydroelectric Power

Hydroelectric Power

• A Dam is made in a river, creating a lake• Water flows through the dam to a turbine and

out into a river again

The Good

• Can create electricity when you need it and scale back when you don’t

• Doesn’t pollute the air• Creates large body of water which can also be

used for farming

The Bad

• Destroys ecosystems – The dry land and its plants, and animals are all

under water– The shallow water is replaced with a deep lake

• Cannot be used all the time for water would run out

• Requires large areas of land and lots of initial investment

Nuclear Power

Nuclear Power

• Uranium is a radioactive material that is mined• The uranium produces heat and heats up

water water turns to steam steam turns the turbine creating electricity

Nuclear Reactor

The Good

• Produce electricity whenever you need it• Can produce very reliable energy• Relatively inexpensive electricity• Can build a power plant almost anywhere

The Bad

• Potential for disaster– Chernobyl– Fukushima

• Mining destroys land and ecosystems• Disposal of radioactive wastes– Wastes last for over 100 years– Storage concerns – St. Louis

St. Louis Post DispatchNPR

Solar Power

Solar Power

• The term “sol” means “sun”• Solar power is power from the sun. • Passive– Use sunlight to warm a room or building

• Active– More advanced– Can create electricity

Passive Solar Power• Have large windows on

the southern side of a building to let the winter sunlight in.

Passive Water Heaters• Uses

solar energy to heat a home’s water

Photovoltaic Cell (PV Cell)• Electricity-producing devices made of

semiconductor materials. • Can produce electricity only during the day• Clouds, rain, snow, debris such as leaves can all

block sunlight• Some places

like Nevada get lotsof sun, Nevada gets 292 days of sunlight a year.

Concentrating Solar Power• Energy from the sun is focused in small area to

heat up liquid (normally oil) which in turn heats of water to produce steam which will turn a turbine to produce electricity.

The Good

• Solar Power doesn’t pollute• Solar Power can be installed in remote

locations and can power a single house, or have power go into a grid.

• Solar panels give you power during the day when demand for electricity is highest

The Bad

• Solar power will not work at night without batteries, which are expensive and require upkeep

• Solar power will not work year round everywhere, like Alaska where they don’t get as much sunlight.

• Solar power is expensive for how much electricity is initially produced.

Biomass Energy

Biomass Energy

• Biomass from biological materials– Renewable energy

source• Most commonly trees,

crops, alcohol fuels, garbage, and landfill gasses.

Biomass Energy

• Can be done on small or large scale– (small) burning wood in a fireplace– (large) ethanol power plant

• Is done to supplement gasoline – In missouri 10% ethanol blend– Potential problem – Ethanol burns hotter than

gasoline

Controversy

• In 2012 40% of corn went to produce ethanol because of government mandate

• Most goes to feed livestock• Less than 9% is used for human consumption

either as corn or as corn syrup in food and drink

Corn power vs. fossil fuels

• You can keep growing corn, whereas however much oil is on Earth now is as much as there will ever be.

• Corn can be turned into ethanol without destroying new ecosystems

• Corn eases our dependence on foreign countries.

Facts

• It takes about 26.1 pounds of corn to create a gallon of ethanol

• Ethanol costs about $1.74 a gallon • Burning firewood can be up to 10 times less

expensive then oil• Burning firewood can be hazardous to your

health

The Good

• Biomass is renewable • Biomass can get a second use out of scrap or

waste materials• Biomass is readily available anywhere in the

world

The Bad

• Biomass pollutes the air • Using biomass for fuel can cause prices of

things like corn to go up.• Biomass can make pollute water

Wind Energy

Wind Energy• The Babylonians and Chinese were using wind

power to pump water for irrigating crops 4,000 years ago, and sailing boats were around long before that.

• Wind power was used in the Middle Ages, in Europe, to grind corn, which is where the term "windmill" comes from.

Wind

• Missouri has most of itswind farms in the northwestern corner of the state

Wind Turbine

Wind Farms

• Wind turbines do require maintenance– Good paying job, must not be afraid of heights,

small spaces, working with high voltage electricity

The Future

• Potential for gaining wind movement from alternative areas, such as by highways

The Good

• Wind is free, wind farms need no fuel. • Produces no waste or greenhouse gases. • The land beneath can usually still be used for

farming.

The Bad• The wind is not always predictable - some days

have no wind. • Best areas for wind farms are often near the

coast, where land is expensive.• Can kill birds - migrating flocks tend to like strong

winds. Splat! (the American Bird Conservancy estimates that US wind turbines kill between 75,000 and 275,000 birds per year)

• Noisy. A wind generator makes a constant, low, "swooshing" noise day and night, which can drive you nuts.

Fossil Fuels

Fossil Fuels

Coal, Oil, and Natural Gas

Fossil Fuels

• Formed hundreds of millions of years ago.– Formed from plant materials in swamp lands, that

were eventually covered by rocks and compressed for millions of years

Coal• Coal is a black rock that must be mined, made up

mostly of carbon.• Is moved by train, ship, or even pipeline– When moved by pipeline, is broken up and moved in

water as a thick sludge, and then dried once it gets to its destination

• Power’s most of St. Louis– Have 30 days of coal stored

in case of an emergency

Oil• Oil is drilled and pumped out of the ground– Largest reserves under the ocean, in the artic, and in

the middle east• Includes gasoline• Necessary to make plastics & even some medicines

Natural Gas• Colorless odorless flammable gas found

underground.– Strong rotten egg like smell added after removed from

ground, so you can identify if there is a leak• Largest underground storage in the U.S. is in St.

Louis. -- north of St. Louis City– In natural cave, level is regulated by pumping water in

and out of cave system

Fracking• Fracking or Hydraulic Fracturing is a method of

extracting Natural Gas from the Earth.– “fracking involves pumping millions of gallons of

chemically treated water into deep shale formations at pressures of 9000 pounds per square inch or more. This fluid cracks the shale or widens existing cracks, freeing hydrocarbons to flow toward the well.”

– Known to cause Earthquakes – Drilling produces millions of gallons of contaminated

water.

Burning Fossil Fuels• Burning fossil fuels releases carbon dioxide,

and other gasses into the atmosphere• Pollutes the land and water too• Powers around 85% of the U.S.– Electric power plants– Cars– Boats– Trains– Engines of all

types

The Good• Can produce electricity whenever you need it• Reliable technology • Inexpensive electricity

The Bad

• Pollutes the air, land, and water• Requires mining (coal), drilling (oil & natural

gas)• Occasionally there are oil spills which

devastate ecosystems

Geothermal Energy

Geothermal Energy

• The term Geo means “the earth” • The term thermal means “heat”– Geothermal is energy we get from the heat of the

Earth• It is a renewable energy• Started thousands of years ago, by taking

advantage of hot springs for heat

Geothermal Electricity• To produce electricity from Geothermal heat

water is pumped deep underground to where it is hot

• Hot water, or steam comes back up and turns a turbine.

Iceland• Known as “the land of fire and ice”– 90% of people heat their homes from geothermal

energy

Heating and Cooling your home

• Summer– Water is pumped into pipes that go into the ground

and is cooled to 58 degrees, that water cools the air that is pumped throughout the house

• Winter– Water is pumped into pipes that go into the ground

and is heated to 58 degrees, that water warms the air that is pumped throughout the house

The Good

• Renewable energy source• Can both heat and cool a home• Low maintenance for power plant or home

heating and cooling

The Bad

• Only available for power plants in certain locations

• Over time hot spots can cool and become less effective

• Can release poisonous gasses such as sulfur dioxide and silica

Review

• Which sources are renewable?

Hydro Wind Nuclear

Geothermal Solar Biomass

Fossil Fuels Hydrogen