APES UNIT 9: Nonrenewable Energy Resources

Renewable energy

(sun, water, wind, biomass, etc.): provides 18% of the world's energy

Formation and Extraction of Coal

-After plants died they underwent chemical decay to form PEAT. -Over years thick peat layers formed. -Peat layers were subjected to high temperatures and pressures to eventually form coal. -Coal is extracted via underground mining- area strip and contour mining

Pros of tracking

-Allows access to previously inaccessible deposits of natural gas -Reduces prices of natural gas by increasing supply

Decommissioning Nuclear Plants

-Cost is billions of dollars. -Experimental breeder nuclear fission reactors have proven too costly to build and operate -Attempts to produce electricity by nuclear fusion have been unsuccessful

Where do most US oil imports go?

About 60% of U.S oil imports goes through refineries in hurricane-prone regions of the Gulf Coast

Bitumen

Bitumen is a tar-like substance that has a high sulfur content. There are many deposits of this in Canada.

Sources of high-level radiation

Fuel rods from nuclear power plants

Ionizing radiation examples

Gamma, ultraviolet

Effect of heating the water and processing the crude bitumen

Heating the water and processing the crude bitumen -- a heavy, viscous oil -- produces carbon dioxide

Where can natural gas be found?

Normally found above oil deposits, but can also be found in frozen formations in the ocean

Problems of shooting radioactive waste into space or into the sun

costs, accident would affect large area

Pebble bed modular reactor (PBMR)

smaller reactors that minimize the chances of runaway chain reactions

Environmental Impacts of Coal

*highest environmental impact of any fossil fuel* -Land disturbance. Little land restoration done. -Air pollution (sulfur and nitrogen emissions) -CO2 emissions and particulates -Release of toxic mercury and radioactive materials when burned -Water pollution -Mining of coal is the deadliest job

Ways to get rid of radioactive waste

- bury it deep underground - shoot it into space or into the sun - bury it under the Antarctic ice sheet - bury it into the Yucca Mountain (US)

"Cons" of methane hydrates

-Because methane is considered to be a greenhouse gas that is more potent than carbon dioxide, some people fear that if the climate gets too warm, they will melt and release more methane into the atmosphere -Burning methane hydrates will release fossil carbon back into the atmosphere, increasing greenhouse gas emissions

Process of refining crude oil

-Crude oil is transported to a refinery by pipeline, truck, or oil tanker. -At the refinery it is heated and distilled to separate it into components with different boiling points. -By products of oil distillation include: paints, plastics, synthetic fibers (Based on boiling points, components are removed at various layers in a giant distillation column. The most volatile components with the lowest boiling points are removed at the top)

Effects of Radiation

-Genetic damages: from mutations that alter genes -Genetic defects can become apparent in the next generation -Somatic damages: to tissue, such as burns, miscarriages & cancers

High-level radiation

-Gives off large amount of radiation -No agreement about a safe method of storage

Low-level radiation

-Gives off low amount of radiation -1940 - 1970 most was dumped into the ocean -Today deposit into landfills

Environmental problems of Heavy Oils from Oil Sand and Oil Shale

-High sulfur content. -Extracting and processing produces: -Toxic sludge -Uses and contaminates -larges volumes of water -Requires large inputs of natural gas which reduces net energy yield

Three Mile Island

-March 29, 1979, a reactor near Harrisburg, PA lost coolant water because of mechanical and human errors and suffered a partial meltdown -50,000 people evacuated & another 50,000 fled area -Unknown amounts of radioactive materials released -Partial cleanup & damages cost $1.2 billion -Released radiation increased cancer rates

Where can methane hydrates be found?

-Methane hydrate is stable in ocean floor sediments at water depths greater than 300 meters -It is known to cement loose sediments in a surface layer several hundred meters thick

Environmental impacts of exploration in Alaska

-Minimal damage to earth's surface. -Transporting it- major problems with oil spills on land and in water. -1989 Exxon Valdez Oil spill- 11 million gallons dumped into Prince William Sound (Alaska)

Oil explosion on the Deepwater Horizon

-On April 20, 2010, an explosion on the Deepwater Horizon drilling platform in the Gulf of Mexico caused the rig to sink and killed 11 workers. As a result, oil began leaking into the Gulf creating the largest spill in American history to date. -Over the course of 87 days an estimated 4.9 million barrels of oil were released into the Gulf. -This spill impacted wildlife, habitats, fishing communities, and commerce along the large coastal areas of Louisiana, Mississippi, Texas, Alabama, and Florida

Keystone XL Pipeline

-Pipeline project that extends from Hardisty, Canada to Illinois -Proposed expansion to Port Arthur, TX -Source of oil is the oil sands in northern Canada

Cons of tracking

-Possible contamination through overflow or leaking of storage ponds -Possible contamination of soil if wastewater is used to water crops or sprayed on neighboring land -Contamination of water by released natural gas -Natural gas released into air adds to greenhouse gases -Uses large quantities of water

Ways to extract oil

-Satellites help find oil deposits today. -High tech equipment can drill oil wells to a depth of 4 miles. -Oil is deposited into the cracks of rocks. -Well is drilled and oil is removed by pumping it to the surface

Exploration in Alaska?

-Since 1980, oil companies have been lobbying to open this area for exploration. -They would like to drill in 1.5 million acres of the 17.5 million acres. -Estimated that the reserves would meet U.S. needs for 7-24 months. -Environmentalists encourage the production of more fuel efficient vehicles

Net energy

-The amount of usable energy available minus the amount of energy used to find, extract, process, and transport it to consumers. -Think of it as your net income (after taxes) -Higher the number the greater the net energy.

The Chernobyl Nuclear Power Plant Accident

-The world's worst nuclear power plant accident occurred in 1986 in Ukraine. -The disaster was caused by poor reactor design and human error. -By 2005, 56 people had died from radiation released. 4,000 more are expected from thyroid cancer and leukemia.

Future of Natural Gas

-U.S. production has been on an upswing, but it is very difficult to predict how long we can use our supplies (100 yrs?) -Canada expected to peak at production by 2030. -Largest suppliers- US, Russia and Canada

Three options to oil

-look for more oil -use or waste less oil -use something else

Parts of a Nuclear Reactor

1) core 2) control rods 3) moderator 4) coolant 5) containment vessel 6) dry casks or water pools

List the three types of energy resources

1) fossil fuels 2) nuclear energy 3) renewable energy

Two types of radioactive waste

1) low-level radiation 2) high-level radiation

Uses of natural gas

1. Run heaters 2. Fuel- Compressed Natural Gas for Taxis. EPA encourages a Natural Gas Taxi Program 3. Run turbines that produce electricity. Pluses include produces less air pollution, high energy yield, cheaper per kWh than coal powered plants

How many metric tons of oil sand does it take to produce one barrel of oil?

1.8 metric tons

Organization of Petroleum Exporting Countries (OPEC)

11 countries have 78% of the world's reserves: Algeria, Indonesia, Iran, Iraq, Kuwait, Libya, Nigeria, Qatar, Saudi Arabia, United Arab Emirates, & Venezuela

When did US oil production peak?

1974

Largest reserve in North America

Alaska North slope has the largest reserve in North America

Nonionizing radiation examples

Alpha, infrared

Arctic National Wildlife Refuge (ANWR)

Artic National Wildlife Refuge (ANWR) is a fragile ecosystem that supports diverse community of species.

Why is burning natural gas better than burning fossil fuels?

Burning natural gas produces less pollution and CO2 emissions than other fossil fuels per unit of energy

Burying radioactive waste in the Yucca Mountain

Bury it into Yucca Mountain in desert of Nevada Cost of over $ 50 billion ~100 miles from Las Vegas Transportation across the country via train & truck

Top 5 countries providing crude oil to the US

Canada - 29% Saudi Arabia - 14% Venezuela - 11% Nigeria - 10% Mexico - 8%

Nuclear Fission

Certain isotopes (uranium 235) split apart into lighter nuclei when struck by neutrons. Chain reaction releases E

Clean coal

Clean coal technology seeks to reduce harsh environmental effects by using multiple technologies to clean coal and contain its emissions

Coal cleaning

Coal Cleaning - Methods of removing sulfur from coal include cleaning, solvent refining, gasification, and liquefaction. Scrubbers are used to trap SO2 when coal is burned

How is coal formed?

Coal is a solid fossil fuel that is formed in several stages as the buried remains of land plants that lived 300-400 million years ago

Crude oil (petroleum)

Crude Oil (Petroleum) is a thick, black liquid made of hydrocarbons, sulfur, oxygen and nitrogen impurities

What could be a supplement for conventional oil?

Heavy and tarlike oils from oil sand and oil shale could supplement conventional oil

Where does the US get its oil?

In 2011, 45% of crude oil used was imported Of that 45%, 52% came from the western hemisphere, 22% from the Persian Gulf, 20% from Africa and 6% from other places

Methane Hydrates

It is a crystalline solid consisting of gas molecules, usually methane, each surrounded by a cage of water molecules. It looks very much like water ice

Natural Gas

It is a mixture of 50% - 90% methane, with smaller amounts of ethane, propane, butane, and hydrogen sulfide gas

When must nuclear plants be decommissioned?

Nuclear plants must be decommissioned after 15-60 years

What type of energy has large net energy? Low net energy?

Oil has high net- large, accessible, cheap deposits. Nuclear has low net- expensive

What makes up oil sand?

Oil sand consists of clay, sand, water, and BITUMEN (organic material that is combustible)

What do Oil Shales contain?

Oil shales contain a solid combustible mixture of hydrocarbons called kerogen

How is crude oil produced?

Produced by decomposition of dead organic matter from plants buried under lake and ocean sediments

Where is nuclear energy produced?

Produced in a nuclear power plant, which uses radioactivity to heat water, which turns into steam. The steam turns turbines which are used to generate electricity

How much crude oil can be extracted?

Producers get only about 35% of oil out of oil deposit (remaining heavy crude too hard to extract)

Hydraulic Fracturing (Fracking)

Produces fractures in rock formations that stimulate flow of natural gas or oil

Containment Vessel

Safety feature. Thick walls (concrete and steel) surrounding core that prevent radioactive material from being released

US oil supplies; ending foreign oil reliance

The U.S. - has discovered enough potential oil deposits to reduce its reliance on foreign oil to almost nothing by the end of 2035

Who is the world's largest oil user?

The U.S. - the world's largest oil user - ranges from 4.8% to 15.6% of the world's proven oil reserves

Yucca Mountain, NV

The entire state of Nevada hates the project Deep geologic disposal is still considered to be the best option

Net energy ratios

The higher the net energy ratio, the greater the net energy available. Ratios < 1 indicate a net energy loss

Problem with storage of RW

The problem is how to keep radioactive waste in storage until it decays after hundreds of thousands of years. There are two fundamental prerequisites: stable geological formations stable human institutions over hundreds of thousands of years

Why has there been a recent interest in nuclear energy?

There has been new interest in nuclear power lately because of the concern about the amount of CO2 released by burning coal

Half - Life

Time needed for one-half of the nuclei in a radioisotope to decay and emit their radiation

Other important oil producers not in OPEC

U.S., Canada, & Mexico

U.S. Energy Use

Use 24% of world's energy: * 85% fossil fuels (nonrenewable) * 8% nuclear power * 7% renewable sources We are dependent on importing oil

What is released as coal is burned?

When coal is burned, sulfur is released primarily as sulfur dioxide (SO2 - serious pollutant)

Gasification

With integrated gasification combined cycle (IGCC) systems, steam and hot pressurized air or oxygen combine with coal in a reaction that forces carbon molecules apart. The resulting syngas, a mixture of carbon monoxide and hydrogen, is then cleaned and burned in a gas turbine to make electricity. The heat energy from the gas turbine also powers a steam turbine

Uncontrolled Nuclear fission

atomic bomb

What is the most abundant fossil fuel?

coal

Coal compared to oil and natural gas

compared to oil and natural gas it is not as versatile, has a high environmental impact, and releases much more CO2 into the troposphere

Core

contains fuel rods. Fuel rods are filled with a fuel pellet made of Uranium-238 and Uranium 235 (fissionable)

Nuclear Waste Policy Act of 1982

designed to establish a permanent, underground repository for high-level radioactive waste by the mid-1990s

Problems of burying radioactive waste underground

earthquake, groundwater

General rule for decay

goes through 10 half -lives before it becomes a non-radioactive form

Problems of burying radioactive waste under the Antarctic ice sheet

long-term stability of ice is not known, global warming

Control Rods

made of boron or cadmium. Move in and out of core to absorb neutrons. Regulate how much power is produced

Sources of low-level radiation

nuclear power plants, hospitals & universities

Controlled Nuclear Fission

nuclear reactor

Nonionizing radiation

radiation that does not change the structure of molecules or atoms

Ionizing radiation

radiation with enough energy to change the structure of molecules or atoms

Electrostatic precipitators

remove particulates by charging particles with an electrical field and then capturing them on collection plates

Flue gas scrubbers

remove sulfur dioxide, by spraying flue gas with limestone and water

Coal washing

removes unwanted minerals by mixing crushed coal with a liquid and allowing the impurities to separate and settle before it burns

Dry casks or water pools

used for onsite storage of radioactive material (spent fuel rods). Made of steel. Must be stored for 10,000-240,000 years

Moderator

usually consisting of liquid (water) or solid graphite. Keeps chain reaction going by slowing down neutrons

Coolant

water that circulates throughout core to prevent fuel rods from melting and helps produce steam that makes electricity