APES Energy and Mining Test (Ch. 14, 15, & 16)
saving energy in existing buildings
- insulate the building and plug leaks - use energy-efficient windows: they cut expensive heat losses from a house or other buildings by 2/3, lower cooling costs in the summer, and reduce heating system CO2 emissions. - stop other heating and cooling losses: leaky heating and cooling ducts in attics and unheated basements allow 20-30% of a home's heating and cooling energy to escape - heat houses and other buildings more efficiently: use superinsulation, a geothermal heat pump, passive solar heating, and a natural gas furnace - heat water more efficiently - use energy-efficient appliances : computers, lighting, automatic motion sensors
nuclear fuel cycle
- mining of uranium - processing and enriching the uranium to make fuel - using it in a reactor - building and running a nuclear power plant - safely storing the resulting highly radioactive wastes for thousands of years until their radioactivity worn-out plant by taking it apart and storing its high/moderate level radioactive parts safely for thousands of years
limits of mining lower-grade ores
- requires mining and processing larger volumes of ore, which takes more energy and costs more - dwindling supplies of freshwater needed for mining and processing - growing environmental impact of land disruption along with waste material and pollution produced during mining and processing
sustainable use of nonrenewable minerals
- reuse of recycle metal products whenever possible - redesign manufacturing processes to use less mineral resources - reduce mining subsidies - increase subsidies for reuse, recycling, and finding substitutes
shifting to more sustainable energy use
- walk, bike, or use mass transit or a car pool to get to work or school - drive only vehicles that get at least 40 mpg - have an energy audit done where you live - superinsulate the place you live and plug all air leaks - use passive solar heating - for cooling, open windows and use fans - use a programmable thermostat and energy-efficient heating and cooling systems, lights, and appliances - turn down the water heater's thermostat and insulate hot water pipes - wash laundry in cold water and air dry it on racks
improving energy efficiency
-prolongs fossil fuel supplies -reduces oil imports and improves energy security - very high net energy yield - low cost - reduces pollution and environmental degradation - buys time to phase in renewable energy - creates local jobs
crude oil (petroleum)
a black, gooey liquid consisting mostly of a mix of different combustible hydrocarbons along with small amounts of sulfur, oxygen, and nitrogen impurities; it was formed from the decayed remains of ancient organisms that were crushed beneath layers of rock for millions of years, and the resulting liquid and gaseous hydrocarbons migrated upward through porous rock layers to collect as deposits of oil and natural gas, often trapped together beneath layers of impermeable rock
mineral resource
a concentration of one or more minerals in the earth's crust that we can extract and process into raw materials and useful products as an affordable cost
CO2
a critical and growing problem is that burning oil or any carbon-containing fossil fuel releases this greenhouse gas into the atmosphere, which leads to global warming and climate change
tar sands (oil sands)
a growing source of heavy oil made of a mixture of clay, sand, water, and a combustible organic material called bitumen - problem: developing this resource has major harmful impacts on the land, air, water, wildlife, and climate compared to conventional light oil and tightly held oil from shale rock - problem: extracting, processing, and refining bitumen from this releases 3-5 times more greenhouse gases per barrel of oil
nuclear power plant
a highly complex and costly system designed to perform a relatively simple task: to boil water and produce steam that spins a turbine and generates electricity (uses a controlled nuclear fission reaction to produce the heat)
energy efficiency
a measure of how much useful work we can get from each unit of energy we use. improving this means using less energy to provide the same amount of work in the forms of light, heat, transportation, and other benefits
mountaintop removal
a mining technique in which the entire top of a mountain is removed with explosives. after a mountaintop is blown apart, enormous machines plow waste rock and dirt into valleys below the mountaintops, which destroys forests, buries mountain streams, and increases the risk of flooding
natural gas
a mixture of gases of which 50-90% is methane (CH4). also contains smaller amounts of heavier gaseous hydrocarbons and small amounts of highly toxic hydrogen sulfide (H2S). widely used for cooking, heating space and water, and industrial purposes including production of nitrogen fertilizer
mineral
a naturally occurring chemical element or inorganic compound that exists as a solid with a regularly repeating internal arrangement of its atoms or ions
sand
a nonmetallic mineral resource made of mostly silicon dioxide used to make glass, bricks, and concrete for the construction of roads and buildings
gravel
a nonmetallic mineral resource used to make concrete for road beds
aluminum
a nonrenewable mineral resource used as a structural material in beverage cans, motor vehicles, aircraft, and buildings
steel
a nonrenewable mineral resource used in buildings, machinery, and motor vehicles. a mixture of iron and other elements that gives it certain physical properties
nuclear fusion
a nuclear change at the atomic level in which the nuclei of two isotopes of a light element such as hydrogen are forced together at high temperatures until they fuse to form a heavier nucleus, releasing energy in the process - no risk of a meltdown or of a release of large amounts of radioactive materials, and little risk of the additional spread of nuclear weapons - still in the laboratory stage
nuclear fission
a nuclear reaction in which a massive nucleus splits into smaller nuclei with the simultaneous release of energy
shale oil
a potential supply of heavy oil produced by mining, crushing, and heating oil shale rock to extract a mixture of hydrocarbons called kerogen that can be distilled - problem: low energy yield because it takes considerable energy, money, and water to extract kerogen from the shale rock and convert it to oil - problem: process pollutes large amounts of water and releases a lot more CO2 into the atmosphere
tsunami (tidal wave)
a series of large waves generated when part of the ocean floor suddenly rises or drops; most are caused when certain types of faults in the ocean floor move up or down as a result of a large underwater earthquake
manganese nodules
a small (potato-sized) rock covering large areas of the Pacific Ocean floor and smaller areas of the Atlantic and Indian Ocean floors; contains manganese and some low concentrations of various rare-earth minerals. can be sucked up by giant vacuum pipes or scooped by underwater mining machines
rock
a solid combination of one or more minerals found in the earth's crust. some kinds only contain one mineral, but most consist of two or more minerals. ex: granite is a mixture of mica, feldspar, and quartz crystals
coal
a solid fossil fuel formed from the remains of land plants that were buried 300-400 million years ago and exposed to intense heat and pressure over millions of years. burned in power plants and generates about 45% of the world's electricity. burned in industrial plants to make steel, cement, and other products. - problem: dirtiest fossil fuel; burning it pollutes the air and creates a toxic ash that is difficult to deal with - problem: processes of making it severely degrade land and pollute water and air - problem: releases large amounts of soot (black carbon particles) and even particles of air pollutants like mercury - problem: among the largest emitters of the greenhouse gas CO2
bitumen
a thick, sticky, tar-like heavy oil with a high sulfur content
asthenosphere
a volume of hot, partly melted rock that flows in the mantle
trade-offs of natural gas
advantages: - ample supplies - versatile fuel - medium net energy yield - emits less CO2 and other air pollutants than other fossil fuels when burned disadvantages: - low net energy yield for LNG - production and delivery may emit more CO2 and CH4 per unit of energy produced than coal - fracking uses and pollutes large volumes of water - potential groundwater pollution from fracking
trade-offs of hydrogen fuel
advantages: - can be produced from plentiful water at some sites - no CO2 emissions if produced with use of renewables - good substitute for oil - high efficiency in fuel cells disadvantages: - negative net energy yield - CO2 emissions produced from carbon-containing compounds - high costs create need for subsidies - needs H2 storage and distribution system
trade-offs of synthetic fuels
advantages: - large potential supply in many countries - vehicle fuel - lower air pollution than coal disadvantages: - low to medium net energy yield - requires mining 50% more coal with increased land disturbance, water pollution, and water use - higher CO2 emissions than coal
trade-offs of burning liquid biofuels
advantages: - reduced CO2 emissions for some crops - medium net energy yield for biodiesel from oil palms - medium net energy yield for ethanol from sugarcane disadvantages: - fuel crops can compete with food crops for land and raise food prices - fuel crops can be invasive species - low net energy yield for corn ethanol and for biodiesel from soybeans - higher CO2 emissions from corn ethanol
trade-offs of burning solid biomass
advantages: - widely available in some areas - moderate costs - medium net energy yield - no net CO2 increase if harvested, burned, and replanted sustainably - plantations can help restore degraded lands disadvantages: - contributes to deforestation - clear-cutting can cause soil erosion, water pollution, and loss of wildlife habitat - can open ecosystems to invasive species - increases CO2 emissions if harvested and burned unsustainably
trade-offs of coal
advantages: - ample supplies in many countries - medium to high net energy yield - low cost when environmental costs are not included disadvantages: - severe land disturbance and water pollution - fine particle and toxic mercury emissions threaten human health - emits large amounts of CO2 and other air pollutants when produced and burned
trade-offs of conventional oil
advantages: - ample supply for several decades - net energy yield is medium but decreasing - low land disruption - efficient distribution system disadvantages: - water pollution from oil spills and leaks - environmental costs not included in the market price - releases CO2 and other air pollutants when burned - vulnerable to international supply interruptions
trade-offs of large-scale hydropower
advantages: - high net energy yield - large untapped potential - low cost electricity - low emissions of CO2 and other air pollutants in temperate areas disadvantages: - large land disturbance and displacement of people - high CH4 emissions from rapid biomass decay in shallow tropical reservoirs - disrupts downstream aquatic ecosystems
trade-offs of wind power
advantages: - high net energy yield - widely available - low electricity cost - little or no direct emissions of CO2 and other air pollutants - easy to build and expand disadvantages: - needs backup or storage system when winds are down - visual pollution for some people - low level noise bothers some people - can kill birds if not properly designed and located
trade-offs of solar thermal systems
advantages: - high potential for growth - no direct CO2 emissions or other air pollutants - lower costs with natural gas turbine backup - source of new jobs disadvantages: - low net energy yield and high costs - needs backup or storage system on cloudy days - requires high water use - can disrupt desert ecosystems
trade-offs of conventional nuclear fuel cycle
advantages: - low environmental impact (without accidents) - emits 1/6 as much CO2 as coal - low risk of accidents in modern plants disadvantages: - low net energy yield - high overall cost - produces long-lived, harmful radioactive wastes - promotes spread of nuclear weapons
trade-offs of solar cells (PV cells)
advantages: - medium net energy yield - little or no direct emissions of CO2 and other air pollutants - easy to install, move around, and expand as needed - competitive cost for newer cells disadvantages: - need access to sun - some designs have low net energy yield - need electricity storage system or backup - costs high for older systems but dropping rapidly - power plants could disrupt desert ecosystems
trade-offs of passive or active solar heating
advantages: - medium net energy yield - very low CO2 emissions and other air pollutants - very low land disturbance - moderate cost (passive) disadvantages: - need access to sunlight 60% of the time during daylight - sun can be blocked by trees and other structures - high installation and maintenance costs for active systems - need backup system for cloudy days
trade-offs of geothermal energy
advantages: - medium net energy yield and high efficiency at accessible sites - lower CO2 emissions than fossil fuels - low cost at favorable sites disadvantages: - high cost except at concentrated and accessible sources - scarcity of suitable sites - noise and some CO2 emissions
coal bed methane gas
an unconventional natural gas found in coal beds across the US and Canada; environmental impacts of using this include scarring of land, depletion of water sources, and possible pollution of aquifers
methane hydrate
an unconventional natural gas, which is methane trapped in icy, cage-like structures of water molecules buried under arctic permafrost in tundra areas and on parts of the ocean floor; so far, it costs too much to extract this resource and it might release a large amount of methane to the atmosphere during removal
strip mining
any form of mining involving the extraction of mineral deposits that lie in large horizontal beds close to the earth's surface - area vs. contour strip mining
hydropower
any technology that uses the kinetic energy of flowing and falling water to produce electricity. it is an indirect form of solar energy because it depends on heat from the sun evaporating water
nonrenewable
because minerals take millions of years to form, they are _____________ resources, meaning that their supplies can be depleted
ethanol
can be made from plants such as sugarcane, corn, and switch grass or from agricultural, forestry, and municipal wastes. this process involves converting plant starches/other plant materials into simple sugars, which are processed to produce this
petrochemicals
chemicals obtained by refining crude oil. used as raw materials to make industrial organic chemicals, cleaning fluids, pesticides, plastics, synthetic fibers, paints, medicines, cosmetics, ice cream, and more
carbon
coal is mostly made of this element, although it also contains small amounts of sulfur. when coal burns, the sulfur is converted to SO2.
high grade ore
contains a large concentration of the desired mineral
low-grade ore
contains a smaller concentration of the desired mineral
coal liquefaction
conversion of solid coal to a liquid hydrocarbon fuel such as synthetic gasoline or methanol. the process is also known as "Coal to X" where X can be many different hydrocarbon-based products
refining
crude oil cannot be used as it is. in this process, it is heated to separate it into various fuels and other components with different boiling points - requires an input of high-quality energy and decreases the net energy yield
proven oil reserves
deposits from which the oil can be extracted profitably at current prices with current technology
hydrothermal ore deposits
form when superheated, mineral-rich water shoots out of vents in volcanic regions of the ocean floor. as the hot water comes into contact with cold seawater, black particles of various metal sulfides participate out and accumulate as chimney-like structures near the hot water vents
hydrogen fuel cell
generates electricity by reacting hydrogen with oxygen (2H2 + O2 --> 2H2O + energy) - takes in hydrogen gas and separates the hydrogen atoms' electrons from their protons. the electrons flow through wires to provide electricity, while the protons pass through a membrane and combine with oxygen gas to form water vapor - the reverse of electrolysis, the process of passing electricity through water to produce hydrogen fuel
geothermal energy
heat stored in soil, underground rocks, and fluids in the earth's mantle. we can tap into this to heat and cool buildings and to produce electricity
reserves
identified deposits from which we can extract the mineral profitably at current prices; can be expanded when we find new, profitable deposits or when higher prices or improved mining technologies make it profitable to extract deposits that previously were considered too expensive to remove
overburden
layer of soil and rock overlying a mineral deposit. surface mining removes this layer.
open-pit mining
machines are used to dig very large holes and remove metal ores containing copper, gold, or other metals, or sand, gravel, or stone
materials revolution
materials such as silicon, ceramics, and plastics are replacing metals for common uses
heap leaching
mining process where cyanide solution is sprayed on piles to dissolve gold; mine the ore, crush/agglomerate the ore, irrigate the ore to dissolve the metal, collect the leachate in a pond or tank, process this solution to recover the metals
liquefied petroleum gas (LPG)
mixture of liquefied propane (C3H8) and butane (C4H10) gas removed from natural gas with high pressures to be used as a fuel. stored in pressurized tanks for use mostly in rural areas not served by natural gas pipelines
ocean
most of the chemical elements and compounds found in the _______ occur in such low concentrations that recovering these mineral resources takes more energy and money than they are worth; on the other hand, in sediments along the shallow continental shelf and adjacent shorelines, there are significant deposits of minerals
decades ago
most of the world's oil comes from huge oil fields that were discovered ______ (recently/decades ago). production from many of these fields have begun to decline and new fields are getting harder to find and more expensive to develop.
horizontal drilling, fracking
natural gas can be extracted through these processes
liquefied natural gas (LNG)
natural gas converted to liquid form by using high pressures and cooling it at a very low temperature; highly flammable liquid is transported in refrigerated tanker ships across oceans. when it reaches the destination port, it is heated and converted back to the gaseous state to be distributed
tight gas
natural gas held in reservoirs of low permeability that cannot be accessed in an economically reasonable time by natural flow methods. the rocks aren't porous meaning more energy is used to extract this
unconventional natural gas
natural gas that is more difficult to access and therefore more expensive to extract than "conventional" reserves - coal bed methane - methane hydrate
acid mine drainage
occurs when rainwater that seeps through an underground mine or a spoils pile from a surface mine carries sulfuric acid to nearby streams and groundwater
volcano
occurs where magma rising in a plume through the lithosphere reaches the earth's surface through a central vent or a long crack, called a fissure. magma that reaches the surface is called lava and often builds into a cone
availability
oil ________ is determined mostly by five factors that can change over time 1- the demand for the oil 2- the technology used to make it available 3- the rate at which we can remove the oil 4- the cost of making it available 5- its market price
tight oil
oil that is held tightly in rocks, and is therefore difficult to extract, however, is becoming more economic to do so; the removal of this from rocks is often known as "fracking"
biomining
one way to improve mining technology and reduce its environmental impact is to use this biological approach where miners use natural or genetically engineering bacteria to remove desired metals from ores through wells bored into the deposits. this leaves the surrounding environment undisturbed and reduces pollution. however, it is very slow compared to the conventional methods
tailings
ore extracted by mining typically contains the ore mineral (the desired metal) and waste material. removing the waste material from ores produces these that are left in piles or put into ponds where they settle out. particles of toxic metals in these piles can be blown by the wind or washed out by rainfall to contaminate surface water/groundwater
coal formation
peat (not a coal) --> lignite (brown coal) --> bituminous (soft coal) --> anthracite (hard coal)
biomass
plant materials (woods or agricultural waste) that we can burn directly as a solid fuel or convert into gaseous or liquid biofuels; an indirect form of solar energy because it consists of combustible organic compounds in plant matter produced by photosynthesis
wind power
power obtained by harnessing the energy of the wind.
solution mining (in situ leaching)
process used to recover minerals such as copper and uranium through boreholes drilled into a deposit; water is flushed through underground wells, hot water is mixed with water soluble vitamins and minerals, and the brine created is extracted
sedimentary rock
rock made of sediments (dead plant and animal remains and tiny particles of weathered and eroded rocks). these sediments are transported and then deposited in layers that accumulate over time. eventually, the increasing weight and pressure on the underlying layers convert the layers into rock ex: sandstone, shale, dolomite, limestone, lignite, bituminous coal
ore
rock that contains a large enough concentration of a particular mineral (often a metal) to make it profitable for mining and processing
metamorphic rock
rocks formed when an existing rock is subjected to high temperatures, high pressures, chemically active fluids, or a combination of these agents ex: slate, marble
igneous rock
rocks that form below or on the earth's surface under intense heat and pressure when magma wells up from the earth's mantle and then cools and hardens ex: granite, lava rock
surface mining
shallow mineral deposits are removed by this, in which vegetation, soil, and rock overlying a mineral deposit are cleared away - strip mining - mountaintop removal
synthetic natural gas (SNG)
solid coal can be converted to this through the process of coal gasification, which removed sulfur and most other impurities from coal. then, we can convert it into liquid fuels through a process called coal liquefaction. these fuels (synfuels) are often referred to as cleaner versions of coal and can then be turned to liquid fuel (synfuels) - problem: producing these requires the mining of 50% more coal - problem: could add 50% more CO2 into the atmosphere - problem: takes large amounts of water to be produced
magma
some of the molten rock in the asthenosphere flows upward into the crust, where it is referred to as this
passive solar heating system
system that captures sunlight directly within a structure and converts it into low-temperature heat for space heating or for heating water for domestic use without the use of mechanical devices - water tanks and walls can store much of the collected solar energy as heat and release it slowly throughout the day or night
active solar heating system
system that uses solar collectors to capture energy from the sun and store it as heat for space heating and water heating
subsidence
the collapse of land above some underground mines. damages houses, cracks sewer lines, breaks gas mains, and disrupts groundwater systems
lithosphere
the combination of the crust and the rigid, outermost part of the mantle; this zone is where we find the mineral resources on which we depend
core
the earth's innermost zone; extremely hot with a solid inner part, surrounded by molten rock and semisolid material
energy return on investment (EROI)
the energy obtained per unit of energy used to obtain it
grade
the environmental impacts of mining a metal ore are determined partly by the ore's percentage of metal content, or ________ - the lower this is, the more money, energy, water, and other resources are needed. also, mining will lead to more land disruption, mining waste, and pollution
subsurface mining
the extraction of mineral and energy resources from deep underground deposits through tunnels and shafts; miners dig a deep, vertical shaft, blast open subsurface tunnels and chambers to reach the deposit, and use machinery to remove the resource and transport it to the surface; disturbs less than 1/10th as much land as surface mining disturbs and usually produces less waste material. however, it creates hazards like cave-ins, explosions, and fires
conventional light oil
the extraction, processing, and burning of this has severe environmental impacts, including land disruption, greenhouse gas emissions, and other forms of air pollution, water pollution, and loss of biodiversity
tectonic plates
the flows of energy and heated material within the earth's convection cells are so powerful that they have caused the lithosphere to break up into these which move extremely slowly atop the asthenosphere
rock cycle
the interaction of physical and chemical processes that change the earth's rocks from one type to another. rocks are recycled over millions of years by three processes - erosion, melting, and metamorphism which produce sedimentary, igneous, and metamorphic rocks
higher
the more accessible, _______ (higher/lower) grade ores are usually exploited first
uranium-235
the nuclear fission reaction takes place in a reactor; the fuel for a reactor is made from THIS ore mined from the earth's crust.
crust
the outermost and thinnest zone of solid material; consists of the continental crust (underlies the continents) and the oceanic crust (underlies the ocean basins)
peak production
the point in time when the pressure in an oil well drops and its rate of conventional crude oil production starts declining (usually a decade after pumping); globally occurs when the rate of global production of conventional oil begins to decline faster than new oil fields are found and put into production
smelting
the process by which ore is melted to separate the useful metal from other elements; heating ores to release metals emit enormous amounts of air pollutants, which damage vegetation and acidify soils in the surrounding area. also cause water pollution and produce liquid and solid hazardous wastes that require safe disposal
fracking
the pumping of water at high pressure to break apart rocks in order to release natural gas - requires enormous volumes of water, which might deplete aquifers, degrade aquatic habitats, and diminish water availability - fluids used contain potentially hazardous chemicals, leading to millions of gallons of wastewater that is brought to the surface that might be hard to store - leads to mining for a certain type of sand required in the process - might be causing earthquakes
geology
the science devoted to the study of dynamic processes taking place on the earth's surface and in its interior
mantle
the thick zone surrounding the core made mostly of solid rock that can be soft and pliable at very high temperatures
depletion time
the time it takes to use up a certain proportion of the reserves of a mineral at a given rate of use - the shortest time estimate assumes no recycling or reuse and no increase in reserves - a longer time estimate assumes that recycling will stretch existing reserves and that better mining technology, higher prices, or new discoveries will increase reserves - the longest time also includes reuse and reduced consumption to further expand reserves
net energy yield
the usable amount of high-quality energy available from an energy resource; total amount of energy available from an energy resource minus the energy needed to make the resource available to us
oil
the world's most widely used energy resource. used to heat our homes, grow most of our food, make other energy resources available for use, and manufacture most of the things we use every day, from plastics to cosmetics to asphalt on roads
manganese, cobalt, chromium, platinum
there are serious concerns about access to adequate supplies of these four strategic metal resources, which are essential for our country's economic and military strength. the US has little or no reserves of these metals
rare-earth elements
these elements are not actually rare, but they are hard to find in concentrations high enough to extract and process at an affordable price. there is no global shortage of these
internal combustion engine
this that propels most motor vehicles wastes about 80% of the high quality energy in its fuel
seismic map
to identify potential oil deposits, scientists use large machines to pound the earth, which sends shock waves deep underground. then, they measure how long it takes for the waves to be reflected back. this information is converted into a 3D _________ _____ of the underground, showing the locations and sizes of various rock formations
cogeneration
to improve energy efficiency in industries and utilities, this involves using a combined heat and power (CHP) system. the steam used for generating electricity in a CHP system can be captured and used again to heat the power plant or other nearby buildings, rather than released into the environment as waste heat.
convection cells (currents)
tremendous heat within the core and mantle generate these that slowly move large volumes of rock and heat in loops within the mantle like gigantic conveyor belts
area strip mining
type of surface mining used where the terrain is flat; an earthmover strips away the overburden, and a power shovel digs a cut to remove the mineral deposit. after removal of the mineral, the trench is filled with overburden, and a new cut is made parallel to the previous one
hydrothermal reservoirs
underground zones of porous rock containing hot water and steam that can be naturally occurring or human-made. we drill wells into these to extract their dry steam, wet steam, or hot water, which are then used to heat homes, provide hot water, grow vegetables in greenhouses, raise fish in aquaculture ponds, and spin turbines to produce electricity
spoils
unwanted rock and other waste materials are deposited in these piles. produced when a material is removed from the earth's surface or subsurface by mining, dredging, quarrying, and excavation.
solar thermal systems (concentrated solar power)
use different methods to collect and concentrate solar energy in order to boil water and produce steam for generating electricity. they are often used in desert areas with ample sunlight
contour strip mining
used mostly to mine coal and various mineral resources on hilly or mountainous terrain. huge power shovels and bulldozers cut a series of terraces into the side of a hill. then, earth-movers remove the overburden, an excavator or power shovel extracts the coal, and the overburden from each new terrace is dumped onto the one below. a highwall (highly erodible bank of soil and rock) is leftover
geothermal heat pump system
uses closed-loop or open-loop water sources to heat or cool a house by exploiting the temperature difference between the earth's surface and underground - winter: closed loop of buried pipes circulates a fluid, which extracts heat from the ground and carries it to a heat pump - summer: removes heat from a home's interior and stores it in the ground
seismic waves
vibrations that travel through Earth carrying the energy released during an earthquake; move upward and outward from the earthquake's focus like ripples in a pool of water
photovoltaic cells (solar cells)
we can convert solar energy directly into electrical energy using these; typically thin wafers of purified silicon with trace amounts of metals that allow them to conduct electricity. when sunlight strikes these cells, they produce electricity and many cells wired together in a panel can produce electrical power
economically depleted
we have never completely run out of a nonrenewable mineral resource, but a mineral becomes ______________ ______________ when it costs more than it is worth to find, extract, transport, and process the remaining deposits. at that point, there are 5 choices: recycle or reuse existing supplies, waste less, use less, find a substitute, or do without
earthquake
when a fault (fracture in the earth's crust) forms/when there is abrupt movement on an existing fault, energy that has accumulated over time is released in the form of vibrations called seismic waves that move in all directions through the surrounding rock. mostly occur at the boundaries of tectonic plates
rises
when a resource becomes scarce, its price ________ (rises/decreases). this can encourage exploration for new deposits, stimulate development of better mining technology and make it profitable to mine lower-grade ores; it also encourages a search for substitutes and promote resource conservation