ENERGY

What is Energy

• Energy- Capacity to do work (Joule)• Power-Rate at which work is done (Watt)• Nonrenewable Sources- Limiting amount

– Coal– Oil– Natural Gas– Nuclear

• Renewable Sources- Non-Limiting amount– Wind – Hydropower– Biomass

• Net Energy- Amount of energy actually used by society– This amount is taken away from the energy needed to extract, deliver, and buy

the energy.

History of Energy

Wood → Coal → Oil

Invention of Steam

Engine and loss of wood

resource

Ease of shipping,

storing, and burning

liquid fuel.

Looking in remote

locations to find

Energy Stats

• Fossil Fuels= 86% of world’s commercial needs– 40%- Oil– 23%-Coal and Natural Gas– 7%- Nuclear and Renewable Sources– 1%- Wind and Solar

• World Energy Consumption is RISING– Rapid Growth of developing countries– Rich Countries(20% of pop.) consume 80% of energy– Developing Countries(80%) consume 20%

* Competition for oil will increase*

How Much Energy is Used Each Year?

• US/Canada= >300 GJ/Year– 60 Barrels of Oil

• Poorest Countries= <1 GJ/Year*People in rich countries use as much Energy in one

day that poor county citizens use in one year. *

↑ E Availability ↑ Standard of Living/Wealth

QUESTION: Where is U.S.’s standard of living leading?

Types of Energy Sources: COAL

• Fossilized plant material – Preserved by burial in sediment– Altered by geological factors that compact and it into a

carbon-rich fuel• Nonrenewable: Takes so long to make.

How Much Coal is There?

• World coal deposits are ten times that of Oil and Natural Gas combined.

• Total resource-10 trillion metric tons– Several thousand years of supply– At present rates and amount of resource that are

economically recovered= 200 years.

Who Uses Coal?

• 3 Largest Coal Burning Countries– China– U.S.– Canada

Other Uses of Coal

• Convert Coal to other material– Synthetic Natural Gas• Coal Gasification

– Methanol/Synthetic Gas• Coal Liquefaction

PRO

~Large Potential Supply~Vehicle Fuel Use~Moderate Cost~↓ Air Pollution

CONS

~Low/Moderate Net Energy~Requires 50% more mining~High Water Use

COAL FIRE PLANT

Pros/Cons of COAL

• Pros– Very Plentiful– High net Energy – Low Cost

• Cons– Very high environmental

impact• Air pollution (SO2, CO2)

– Severe land disturbance– High land use– Severe threat to human

health

COAL in the Future

• Since Coal seems to be so plentiful and does produce a high net energy…..– Methods for clarification could lead to more use

– Not as much environmental effects (Air Pollution)

Types of Energy Sources: OIL

• Crude oil is a thick, gooey liquid– Consist of hundreds of combustible hydrocarbons– Small amounts of sulfur, oxygen, and nitrogen.

How was OIL produced

• 3 geological events led to the presence of oil– Sediments buried organic material faster than it could

decay.– Sea floors with these sediments received the right

pressure and heat to convert organic matter to oil.– Oil collected in porous limestone or sandstone and was

capped by shale or silt to keep it from escaping.

OIL Stats

• 25% of U.S. oil is found in Gulf of Mexico• Current U.S. oil production= 8 million barrels

from 533,000 wells per day.• Current Saudi Arabia oil production= 8 million

barrels from only 750 wells per day. • Pumping oil in Saudi Arabia costs < $1.– Market price for oil= Appx. $105

How Plentiful is OIL?

• In 2005, PROVEN RESERVES were roughly 1 trillion barrels.– Enough to last 40 years at current rate of consumption

• Believed that another 1 trillion barrels are not recoverable, or not yet discovered.

• Who has the PROVEN RESERVES?– Saudi Arabia- 25% of total– Kuwait- 10% of total– Persian Gulf Countries- 66% of total

How we use OIL

• Crude oil– is sent to a refinery where it is broken down into

components with different boiling points.– 8% of all U.S. energy consumption

• Petrochemicals– Oil distillation products that are used as raw

materials in manufacturing pesticides, plastics, synthetic fibers, paints, medicines, etc.

Other places to find Oil

• Tar sands– Mixture of clay, sand, water and “tar” (bitumen)– Canada’s reserve can lead to 2 million barrels of oil

per day to the U.S. (will surpass Saudia Arabia)• Oil Shale– Fine-grained sedimentary rock rich in solid organic

material- kerogen• Heat the kerogen to liquid and extract from stone

– Could yield the equivalent of several trillion barrels of oil.

Pros and Cons of Alternative Oil Sources

• Tar Sands– ENVIRONMENT IMPACTS

• Typical plant producing 125,000 barrels/day creates about 15 million cubic meters of toxic sludge, and contaminates billions of liters of water each year.

• Oil Shale – Expensive – Uses a lot of water– High potential for air and

water pollution– Hugh quantities of waste

Pros/Cons of OIL

• PROS– Ample supply for 42-90

years– High net energy– Easily transported– Low land use

• Cons– Expensive– Air pollution when

burned– Environmental Impacts

• Drilling and spills• Habitat destruction• Water pollution

Types of Energy Sources: Natural Gas

• Mixture of gases– > 50% is CH4

• Conventional natural gas– Pipelines– Liquefied petroleum gas (LPG)– Liquefied natural gas (LNG)

• Unconventional natural gas– Coal bed methane gas– Methane hydrate

Natural Gas Stats

• Proven reserves for World= 5,500 trillion cubic feet.– Amount to last 60 years at current consumption

• Proven reserves for North America are 250 trillion cubic feet– 4.6% of world total– 10 year supply at current consumption

How we use Natural Gas

Pros and Cons of Natural Gas

• Pros– High net energy– Low cost – Less air pollution than

other fossil fuels– Low land use– Easily transported

• Cons– Greenhouse gas release

• CO2 when burned• Methane can leak out of

pipelines

– Requires pipelines

Types of Energy Sources: Nuclear

• Uranium 235 and Uranium 238 are common radioactive particles used

• Nuclear Fuel Cycle– Mine the Uranium– Process Uranium to make the fuel– Use it in reactor– Safely store Radioactive waste

How Does a Nuclear Fission Reactor Work?

• Fission- Breaking of atoms

+ 1n + + + Q

Cs + Rb 3nUr-235

Radioactive material

Radioactive Waste Recycled

NeutronsHeat

Control/Protection of Nuclear Reactor

• Control rods– Absorb neutrons

• Coolant– water

• Containment Shells– Surrounds core for protection

*Controlling neutron flow plus water coolant is responsible for keeping the core at correct temperature*

Nuclear Waste and Storage

• High level of radioactive waste• Waste stored in water-filled pools or dry casks

• Problem…Where do we store it?– Deep burial?• Would any method last long enough?• Consider Half-life

-STILL NO FACILITY BUILT!!!

Yucca Mountain Desert Region

• 1985- plans in the U.S. to build a repository for high-level radioactive wastes.

• Problems– Cost: 85-100 billion dollars– Large # of shipments to the site

• Protection from attack?

– Rock fractures– Earthquake zone– Decrease national security

What happened to Nuclear Power

• Slowest growing energy source

• Why?– Economics– Poor management– Low net yield of energy– Safety concerns– Concerns for transportation of uranium

Pros and Cons of Nuclear Energy

• Pros– Large fuel supply– Low environmental

impact (without accidents)

– Moderate land disruption

– Moderate water pollution

– Low risk of accidents

• Cons– High cost– Low net energy yield– Catastrophic accidents

could occur– No long-term storage

solution– Subject to terrorist

attacks