Unit 6 Apes
how to find percent increase in consumption
(initial-final)/initial x 100%= % change
A home uses ten 100-watt lightbulbs for five hours per day. Approximately how many kilowatt-hours of electrical energy are consumed in one year by using the lightbulbs?
10 bulbs x 100 watts = 1kw/hr x 5 hrs/day = 5kw/h per day x 365 = 1825
kW to MW
1000kW=1MW
oil + gas formation
300 to 400 mil. yrs ago organisms(marine) fossils buried under sediment+ sand heat + pressure over time once under water, no on land and becomes these 2
electric cars pros compared to regular
decrease levels of CO2, CO(improve health- can have resp. or brain damage(coma)), SO2, NOx(both acid precip), VOCs/hydrocarbons(decrease secondary pollutants like O3 or PAns- hurt health) particulates, MTBE(less oil spills) less petroleum used- less toxins from mining, fewer oil spills, less extraction- less habitat damage, less noise(reduce impact on human health)
trends with coal
deeper coal buried- more pressure more dense coal- hotter/larger(provides most elec then through steam) all coals gonna release impurities
passive solar examples
double paned windows, south facing winds, no trees blocking south, overhand- allows sun out in warmest and in in coolest months insulation- trap heat deciduous shade trees skylight to reduce elec needs dark colored floors and thermal mass- heat at end of day when none
how also is crude oil(petroleum) extracted
drilling well through layers to reach underground deposit then pumping liquid out under pressure
coal mining
dug out of ground, depends on how deep ground is, surface(main one)- shallow seam of coal, remove topsoil + habitat, overburden, and subsurface- deep, dig tunnels to get coal, destroy habitat and very dangerous
solutions for hydropower
fish friendly turbines/ fish ladders controlling erosion in upstream watersheds managing water elevation more carefully, especially during warm seasons
how is oil + natural gas extracted
formed from plants- caught under earth material decays- from gas + petroleum viscous- thick-petroleum/oil-liquid has to pumped out- most done at sea gas got by hydraulic fracking
what are largest sources of energy
from greatest to least FF- greatest hydroelectric nuclear
crude oil types and why
gasoline, diesel, jet fuel, and heating oil for specialized uses- done by taking different boiling points of fuel. 2nd law of thermodynamics- less energy as it converts to different forms so fossil fuels are not efficient
hydraulic fracking
get natural gas extraction extending access and supply to natural gas- trapped in semi-permeable sedimentary rock(ex. shale)- released by cracking rock w/ pressurized H2O
neg of ethanol
has neg of monocropping- soil erosion, habitat loss, GG, less water, lots of corn needed if use corn one
geothermal
heat from earth comes near crust- natural radioactive decay gives heat ex. upper geyser basin- yellowstone national park or iceland as it sites on the crust
uranium leaders
highest reserve in Aus.(does not rly use), Kazakhstan, and canada
how natural gas processed
in tube-easy to transport but can escape
China's Three Gorges Dam
largest dam in the world lots of habitat destruction disrupts fish
biomass what and use
leading renewable energy, not use for elec, but direct source of heat for developing wood, peat, charcoal(wood), crop residue, manure
lignite
lignite(low heat capacity, low sulfur, high moisture, least valuable)- does not produce that much heat as not as concentrated as hasn't been under heat and pressure as long and has the most impurities
passive solar
like solar oven or how building oriented(coming through windows) heat is directly absorbed from sun w/o mechanical or electric equipment
photovoltaic solar cells(PV)
like solar panels(usually silicon) transform sunlight directly into elec emits low voltage current
problems w/ nuc waste
long lived- hard to store lots of storage on site/ buried deeply people don't want near them many sites- more chance of radioactive waste leaking in env. fissions occurs in reactor so where waste created
Cons of hydroelectric
loses ecosystem sedimentation- build up of sediment behind dam flooding of land for reservoir disrupt flow rates of rivers high construction costs for dams that require FF use most viable sites + already used creates reservoir- more evap upstream much warmer and less O2 with a lot more sediment. downstream loses import nutrient source in sediment- less water dams prevent upstream movement of fish https://dec.vermont.gov/sites/dec/files/wsm/rivers/docs/rv_dameffects.pdf
control rods
lowered into reactor to absorb neutrons and slow down reaction- prevent meltdown
crude oil
middle east, venezuela, canada
env. problems with using coal for elec
mining to get coal- destroy habitat + resource use harm it pulverize call into small thing dust(soot, ash)- flammable + harmful to resp. system lots of water uses which can hurt habitat and water resource CO2(more than must FFs)- climate change as GG releases SOx and NOx(sulfur/nitrogen oxides)- irritate resp. system, smog, acid precip other pollutants from impurities like mercury
as world develops
more demand for FF
bituminous
most common used, high heat capacity, high sulfur(most of all them), in b/w heat
what should rate of consumption be for renewable
must be at/ below rate of regulation for renewable
Fukushima
natural disaster- earthquake caused tsunami and caused emergency shutdown- reactors flooded 3/4 meltdown accident was preventable- made changes like shut down faster and evaluations
hydraulic fracturing(fracking) process
natural gas form under rock layers of rock also hold water near natural gas pores process well made clay/cement lined to prevent ruining groundwater pipe inserted to get natural gas out fracking fluid inserted= water + compounds- allow growth to break and fracture so gas can flow out
cleanest burning fossil fuel
natural gas- least harmful emissions as LEAST IMPURE[filter out as its a gas](still produces carbon) but less sulfur dioxide, mercury, and particulates to coal + oil
how is use of energy resources distributed across the world and what countries lead/how much energy do they use
not evenly distributed between developed(uses lot more) and developing countries US + China- uses 40% of energy as developed 20% of world uses 80& of energy
is coal efficent
not rly- 30%- lots lost as heat- use cogeneration
Cogeneration
not wasting heat by using to make heat and electricity- efficient as prevent heat from dissipating
nonrenewable resource types and meaning
nuclear, fossil fuels(coal, oil, natural gas) depleted by use(exhausted)- not easily replace as process takes long time(for nuclear depends on uranium so once used=done) and making it in lab would take more energy than put out by source
negatives of oil and gas extraction
oil- habitat destruction and potential spills on land or water- hurt organisms gas extraction(hydraulic fracking)- destroy hab, water contaminate, earthquakes
how is nuclear used to make elec
ore= uranium=235 to generate elec steps U-235 place in fuel rods struck by outside neutron process of splitting U-235 releases lots of heat heat will generate stream from water steam- turbine turbine- generator generator- elec
coal deposits
peat within sedimentary rock as precursor
particulates(suspend particle matter)
property damage, less visible, more respiratory problems
pros and cons of biomass
pros: easy access relative cheap use to heat and cooke cons: air pollutants(co2, co, NOx, particulates, VOCs)- can lead to smog also burned indoors usually- hurt health overharvest trees- deforestation- less water and carbon sequestered doesn't inc amounts of carbon as modern carbon(carbon neutral) but lose services like sequester carbon
PV pros and cons
pros: generate elec less habitat destroyed depending on installation- where already disturbed(building) large and small scale applications- off grid- remote places w/o pwr plants cons: use limited by sunlight available- not cost effective as ones that store energy at night cost a lot limited lifespan of non renewable PV cells expensive solar farms may hurt fragile desert ecosystem silicon is limtied resource
active solar pros and cons
pros: generate elec and heat large/small scale applications cons: cost a lot and needs lot of maintenance solar farms may neg impact fragile desert ecosystem solar farms need high solar intensity to make efficient
pros and cons of biofuels
pros: have infrastructure in place- gas pumps carbon neutral carbon-modern carbon potentially renewable- needs time to grow can be produce domestically- national security cons: net energy low- more gasohol needed for same distances harvesting crops for ethanol- inc FF inc deforestation reduce fertility of agr lands
passive solar pros and cons
pros: inexpensive and low maintenance cons: some aspects difficult to implement retroactively- after built energy can't be collected(only stored in thermal mass/insulation)
pros and cons of nuclear energy
pros: low/no CO2, CH4 emissions high power outputs low cost after construction no mine FF no primary/secondary air pollution cons: spent fuel rods + hazardous waste- long lived and lead to nuclear accident thermal pollution if not cooled properly- water can go to nearby water, inc temp, lead to thermal shock- less O2- suffocation very high initial costs nonrenewable mingin for construction + uranium- tailings
pros to hydroelectric power
pros: no air pollution no waste relatively inexpensive once dam built additional service by reservoir(more water irrigation + more fishermen- very useful for ppl) jobs created dams reliable energy source brings in tourists can control downstream seasonal flooding- help humans NOT water body(loses nutrients)
how to do you use coal
pulverize coal- burn better in powder form burn/combust in boiler H2O turned into steam- pushes turbine connects to generator which goes to transformer creates electricity
nuclear pwr emits
radioactive energy nuc pwr from U-235 breaking down and isotope lose energy emits energy as radioactive wave(not easy to store and will remain radioactive) once breaks can't generate heat and U-235 will gather more neutrons and become heavier(like plutonium) has very long half lives until it can safe
what can govt do to control resource use
regulate certain resource CANNOT directly raise or lower prices can inc taxes to discourage or rebates/tax credits to encourage
problem w/ wood + charcoal
remove trees, degrade soil, inc soil erosion(more food insecurities), also less precipitation, less carbon sequestration
natural gas
russia, US
active solar
solar water heater use machine and elec to transform solar heated liquid to heat or elec concentrated liquid heated up w/ sunlight w/ reflective surfaces to help- steam- turbine- generator can give heat and elec
biodiesel sources
soybeans(brazil and US) oil palms(southeast Asia)- more GG as less trees rapeseeds(europe)
combustion
step in co2 cycle chemical process of fuel+o2- CO2 + H2O
Biodiesel
sub for diesels extracted+chemically modified from plants
ethanol
sub for gas corn or sugarcane fermet plant based scratches into sugar then alcohol maybe mixed with gasoline to created gasohol- 10% ethanol E-85 and flex fuel can run on 85% ethanol
biomass energy from
sun's energy from photosynthesis conserved- 1st law of thermodynamic(not created nor destroyed)
what type of fuels do developing nation use
sustenance fuels(easy gather/produce) biomass- wood, charcoal, dried animals
where is crude oil recovered from and how and why
tar sands(mix of water, sand, clay, and bitumen[semi-solid form of petroleum]) not ideal(takes up time and energy and lots of water) but as fossil fuels decrease might need to get oil remove water- remove sand=oil drum purified air and also water filters out impurities
anthracite
the cleanest-burning coal(most valuable), best quality, high heat capacity, low sulfur content(allows for least acid deposition), takes longest to make, most heat as has most carbon, most expensive
advantages of river system and tidal over dam
they run on natural current + no reservoir formed like in damms + allows sediment's natural flow less impactful on ecosystem- but does not generate as much power and unavailable in warmer seasons
1/2 life of radioactive material
time for .5 to decay decays into another atoms- emits radiation 10 .5 lives to be safe(determining half life can determine safety)
more sustainable sources for biofuels
use cleared lands or replant trees ethanol- switch grasses- perennial crop biodiesel- SVO(straight vegetable oil) algae- omega system
peat and where found
used in developing and is precursor to coal- partially decomposed organic material that can be burned for fuel found in soil- the dark, rich organic material found in wet/acidic ecosystems like bogs
wood and charcoal
usually used in developing countries(not much processing + available) charcoal- burns hotter than wood
coal and H2O
very H2O dependent in use to make elec boiling to turn turbine needs for cooling equipment
problems with using wood, charcoal, and peat indoors
w/o proper ventilation can cause health problems w. air pollution
env. problems with fracking
well- can contaminate water/destroy habitat- not usually done in open spaces if pipe not lined properly- contaminate water fracking fluid has volatile organic compounds(VOCs)- can vaporize easily CH4 released fracturing rocks- earthquakes as destabilizes geology- breaks which can contaminate H2O
age of rock determines
what resource will be available- if not enough, resource may not be available
how does dam hydropower work?
when reservoir(body of water created by dam) comes in through gates, has Ek, which spins turbine- turn generator- by electromagnetic induction(motion of wire/magnet- what Ek of generator turns into) to make elec. which will flow to grid water falls under force of gravity through a turbine
uses of wood, charcoal, and peat
wood- heat, light, cook charcoal- heat, cook peat- heat, cook
what factors determine the energy sources used?
availability- what can they get? price- supply + demand govt regulation- what fuels can consumers get?- govt can regulate, subsidies, incetives
3 big nuc pwr accidents and why bad
bad0 can cause gene mutate, cancer, contaminants cuz of radiation, and radiation can spread by wing 3 mile island, penn Chernobyl, Ukraine Fukushima, Japan (either caused by natural/human accidents)
20% of US renewable energy
biofuels
renewable resource types
biomass, hydroelectric, solar, winds, waves, geothermal inexhaustible if PROPERLY MANAGED- replenished naturally
Natural gas is often priced in units of dollars per therm. One therm equals 100,000 BTUs. A certain family uses 600 therms of energy to heat its home annually using a natural gas furnace that is 80 percent efficient. The family is considering replacing its current furnace with one that is 96 percent efficient. Assuming the cost of a therm is $0.30, which of the following would be the family's annual savings in the cost of home heating?
Annual gas usage by a certain family = 600 therms (1 therm = 100,000 BTUs) Efficiency level = 80% If the efficiency level is increased to 96%, there will be a 16% reduction in the quantity of gas by 96 therms, from 600 to 504 therms. Unit cost of a therm = $0.30 The family's annual savings in the cost of home heating = $0.30 * 96 = $28.80
Hydroelectric 3 types
Large scale: dam+reservoir tidal power small scale/off grid: micro hydropower- river/stream
water pump for nuclear
brings in cool water to prevent overheat
if given percent increase
can use it to find doubling time(70/growth rate) and can apply to see how much energy use increases if given that relationship
forms of coal and how do you change it
change by adding heat and pressure peat(precursor/not a coal)- lignite- Bituminous- anthracite goes from worst to best
biofuels sources
corn(US0, sugarcane(Brazil), sugar beats(Us and Brazil lead)
hydrocarbons
FF
what energy is vast majority of US energy use
FF
Biofuels
Fuels, such as ethanol or methanol, that are created from the fermentation of plants or plant products can sub for petroleum products(gasoline or diesel)
gasoline point source and electric non point
Gasoline cars must be identified as a dispersed (non-point, mobile) pollutant source, as opposed to electric cars, which obtain energy from an electrical generating power plant (point source, stationary source).
In many parts of the United States, homeowners use a significant portion of their energy budget to heat their home in the winter. It has been determined that lowering a thermostat by 3°F in the winter can reduce the energy costs by about 10 percent in many homes. An individual homeowner lowers their thermostat by 3 degrees exactly halfway through the billing period. For the month that the thermostat was lowered, the heating bill was $95.
If the family paid $95 for the month, for half of the month they paid 1x and for the other half they paid .9x (a savings of 10%). $95÷1.9x , x=$50 . The bill should have been $50 for each half of the month, but in the second half the bill was only $45 ($95−$50=$45) . This is a savings of $5.00.
How does tidal power work?
The mechanical energy associated with the rising and falling of water levels during the movement of the tides is converted to usable electrical energy. there are turbines in the ocean and tides have kinetic which turned turbine- generator- elec
sedimentary rocks and energy
The vast majority of oil and gas reserves around the world are found in sedimentary rocks. All the source rocks for oil and gas are sedimentary.
where is largest oil sands reserves
alberta canada- extends crude oil supply
cooling tower
allows water to cool
Chernobyl
arose from safety test- pwr turned off in simulation and extra pwr from turbine was supposed to keep reactor powered up enough to kill- miscalculated so when completed, control rods didn't drop explosion- worst as release most radiation ever by accident- many died
nuclear fission
U-235 has neutron shot at high speed- chain reaction it splits into nucleus- release energy to boil the water to steam nucleus provies neutrons- continued fissions
coal + coke
US, russia, china(big role in their emissions output)
3 miles island
accident started in non nuc portion of reactor as water pumped failed to allow water in so reactor never cooled so fuel began to melt down partially- no explosion or long-term radiation exposure
meltdown reactor core
accidental release of radiation
sulfur emissions + h2o vapor
acid deposition
how does energy use change as country develops?
as country develops(goes through demographic transition)- sources of tech develop- uses more energy/FF- rely more on FF for energy increase example: goes from walk- bike- car- airplane as develops
