Environmental Energy Quiz

Electricity Grid

system that distributes power facilitated at various locations to end users over far distances. four components are:  individual generators, transmission, distribution, and consumer use

Issues the need to be addressed with the Grid

 

• Hardware and software needs to be modernized to withstand weather conditions

• High voltage transmission lines need to be added as well as long duration batteries to ensure stability and reliability

• modernized to be able to handle energy demand, increase reliability, make it more stable, and integrate clean energy like solar and wind

• current grid was designed for fossil fuel plants, not for renewable energy, which limits society’s efforts to reach clean energy targets. 

Net Energy Yield

the amount of energy obtained from a resource minus the amount of energy needed to produce it.

Renewable

replenished by natural processes either directly or indirectly from the sun

Non-renewable

exist in a fixe quantity in the earth and can not be replenished in our lifetime

Inexhaustible Resource

natural resources that are available in unlimited quantities and cannot be completely used up by human activities. EX- solar and wind energy

How are fossil fuels created

HEAT + PRESSURE

coal: dead plants buried under water and dirt became coal due to heat and pressure

oil & natural gas: dead plants and animals buried under silt and sand in the ocean. over millions of years, heat and pressure turned them to oil and gas

Pros and Cons (Oil)

Pros: ample supply for several decades, net energy is decreasing, low land disruption, efficient distribution system

Cons: water pollution, oil spills, environmental costs not included in market cost, releases coo2 when burned,

Pros and Cons (Coal)

Pros: medium-high net energy yield, low cost, plentiful

Cons: pollution, toxic emissions threaten human health, emits large amounts of co2 when burned

Pros and Cons (Natural Gas)

Pros: versatile, medium net energy yield, emits less co2 when burned

Cons: fracking uses and pollutes lots of water, potential ground water pollution

Oil - Location, extraction, use

• found under earths surface within the cracks and pores of rock

• crude oil and nat gas often found tg under the sea floor

• wells are drilled which draw out the oil using gravity, pumping it to the earths surface

• The high pressure underground keeps the oil flowing

• crude oil or petroleum is collected then refined

Refining is the process by which oil is heated in order to separate it into different fuels and products based on their boiling points.

Nat gas - Location, extraction, use

• mixture of gases (50%–90% methane)

• Hydraulic fracturing used to extract natural gas from deep underground rock formations

• injecting high-pressure fluid into the rock to create fractures and release the gas

Coal - Location, extraction, use

• coal is a solid fossil fuel that is the dirtiest FF for air and water pollution

• extracted through mining

• used for generating electricity and producing steel

How do fossil fuel power plants work to generate electricity

• Fossil fuel power plants generate electricity by burning fossil fuels like coal, oil, or natural gas to produce heat

• Heat creates steam that drives turbines connected to generators

• Converts mechanical energy into electrical energy

Clean Coal

• a set of technologies designed to reduce harmful pollutant emissions from coal-burning power plants.

• primarily involves carbon capture and storage where CO2 is trapped after combustion and stored underground

• Clean coal is a myth

Coal Ash

• Some coal burning plants use scrubbers to try and remove pollutants. produces coal ash

• Some ash is buried, some gets into the water systems, and some is sold for construction

pollution control devices installed in coal-fired power plants to remove sulfur dioxide (SO2) and other harmful pollutants from exhaust gases before they leave the smokestack

Types of Coal

Hydraulic Fracturing

• method used to extract natural gas from deep underground rock formations by injecting high-pressure fluid into the rock to create fractures and release the gas

Liquified Natural Gas (LNG)

• can be liquefied into liquified petroleum gas (LPG) or Liquified Natural Gas (LNG)

• LPG and LNG are easier to transport than natural gas in its regular form

• primarily used for generating electricity, heating, and as a fuel for vehicles

Crude Oil and Oil Refinement

• crude oil (petroleum) is the raw oil formed beneath the earths surface that we gather, refine, and combust

• Refining = process by which oil is heated in order to separate it into different fuels and products based on their boiling points

• It takes energy which effects the net energy yield of the fuels

• Can create additional pollution by creating petcock (left over black power that accumulates) which blows in the wind

Are we running out of oil?

• amount of oil stored underground is unknown but it is NOT believed the world will run out of oil shortly

• Many oil stores that havnt’t been used

Proven Oil reserves

the deposit from which oil can currently be extracted

Petrochemicals

After refinement, byproducts called petrochemicals can then be used to create other products such as pesticides, plastics, paints, and cosmetics! 

Shale Oil

oil found within layers of rock. Shale oil has a low net energy yield due to the energy needed to extract it. It is not considered an economically practical option

Tar Sands

• oil mixed with clay, sand, water and bitumen – also has a low net energy yield 

  • Bitumen is a tick, sticky heavy oil with a higher sulfur content 

Nuclear Energy- what is it

• The goal of a nuclear power plant is to boil water to produce steam that will spin a turbine and create energy. 

• It is a simple goal, but the process is complex and expensive 

• Nuclear power uses nuclear fission reactions to provide the heat need for the process.

How does it work, the nuclear fuel cycle

• Fuel for a reactor is made from uranium – a ore that is mined from the earths crust 

• The usable uranium is known as uranium-235

• After being minded, the ore must be enriched to make it more concentrated 

• After being enriched, the uranium is processed into pellets of uranium dioxide

• One pellet (the size of a pencil eraser) contains the same amount of energy as 1 ton of coal

Fuel Rods & Fuel Assembly

• pellets are packed into sealed pipes called fuel rods and grouped together to create fuel assemblies which will go into the core of the reactor

• Once the fuel assemblies have been placed in the reactor, operators use control rods to control the amount of power produced

• A coolant (water) is present in the reactor which helps to slow the reaction rate and cool the fuel cells, to prevent melting

A containment shell made of thick metal and concrete surrounds the reactor to keep radioactive material from escaping

Nuclear Waste

• The used uranium rods are highly radioactive and the waste must be handled very carefully to avoid radioactivity from entering the environment

• Rods can remain radioactive for thousands of years

• They are usually stored in underwater pools on the same site as the reactor

• From there, they are often moved to dry storage called dry casks

Basics of Nuclear Fission

process where the nucleus of an atom splits into two or more smaller nuclei, releasing a large amount of energy, neutrons, and radiation

Future of Nuclear

• There is much disagreement about the future of nuclear 

• Facilities are aging 

• Waste storage is problematic

• Building new facilities is costly 

• Nuclear meltdowns are infrequent, but can be very damaging and have become a widespread societal fear 

• Fear of the spread of nuclear weapons 

• An increase in research could lead to newer, safer technology 

• Does produce low greenhouse emissions - low environmental impact

• Mining of uranium ores have an impact

Nuclear Fusion

• two light nuclei merge to form a single heavier nucleus. The process releases energy because the total mass of the resulting single nucleus is less than the mass of the two original nuclei. The leftover mass becomes energy

• produces more energy than fission and only leaves a small amount of short lived radioactive waste

• fusion reactions can be halted much more quickly and easily than fission, the risk of meltdown is almost zero- making fusion much safer than fission