APES Unit 8 Exam
What mixture of gases make up natural gas?
-50-90% methane (CH4) -smaller amounts of propane (C3H8) and butane (C4H10) -very small amounts of toxic hydrogen sulfide (H2S)
What are some possible environmental and health concerns with coal ash contamination? Why do you think wet ash storage is cheaper?
-57% of toxic coal ash is either buried or made into a wet slurry that is stored in holding ponds -can leach into groundwater, break through earthen dams and severely pollute nearby rivers, groundwater, and towns -wet ash storage is cheaper than disposing of it dry because it likely requires less work and maintenance
Read the core case study. What is the total percentage of US energy that comes from renewables? ID two ways that US energy consumption is different from the global averages?
-7% of US energy comes from renewables -US depends on oil more than the rest of the world (40% compared to 34% globally) -US energy coming from renewables is less than the global average (7% compared to 15%)
When referring to "Clean Coal" what is removed? What isn't?
-emissions are attempted to be reduced (CO2 and other air pollutants and (some) sulfur is removed from the coal
What are the steps that must be taken, and energy invested, to mine coal? Where does that energy come from?
-energy to mine coal comes from fossil fuels (gas to power machines, etc) -
How is microhydropower different than dams?
-floating turbines size of a small suitcase that utilize the power of flowing water to turn rotor blades, which spins a turbine to produce electric current -can be placed in any stream/river w/o altering its course to produce electricity at very low cost with very low environmental impact
Why do we waste energy?
-fossil fuels, nuclear power, and other widely used energy sources are artificially cheap (gov't subsidies, environmental and health costs not included in market price) → people more likely to waste -too few economic incentives (tax breaks, rebates, low-interest and long-term loans) for consumers and businesses to invest in improving energy efficiency -people tend to resist change, even when it saves them money
There is current interest in smaller, second-generation Advanced Light-Water Reactors (ALWRs) because they...
-gas-cooled reactors can be used to decompose water into hydrogen fuel -passive safety features render the threat of meltdowns or explosions near impossible
Describe the concept behind a geothermal heat pump.
-geothermal heat pump system can heat/cool a house by exploiting the temperature difference, almost anywhere in the world, between earth's surface and underground at a depth of 3-6 meters (10-20 feet) where the earth's temperature typically is 50-60 degrees F year-round. In winter, a closed-loop of buried pipes circulates a fluid, which extracts heat from the ground and carries it to a home's heat distribution system. In summer, this system works in reverse, removing heat from a home's interior and storing it in the ground
How do we use the heat in our crust to create electricity?
-geothermal heat storage sites not far below the surface can be tapped by pumping water into them → hot water is pumped to the surface and used to heat fluids w/low boiling points → releases vapor that can spin a turbine to generate electricity (inefficient)
Of the bullet point list at the beginnings of 16.9, which are the most important 2 things in your opinion?
-how much of the energy resource is likely to be available in the near future? (the next 25 years) and in the long term (the next 50+ years) -how will extracting, transporting, and using the resource affect the environment, the earth's climate, and human health? Should we include these harmful costs in the market price of the resource through mechanisms like taxing and reducing environmentally harmful subsidies?
Explain why hydrogen has negative net energy. Explain why this is ok.
-hydrogen is a fuel produced by using other forms of energy and thus has a negative net energy yield → it will always take more energy to make it from these sources than the energy we get by burning it as a fuel -however, b/c hydrogen is such a clean burning fuel, it may be eventually be widely used
List three positive outcomes of reducing energy waste.
-save money -sharply reduce CO2 emissions and other air pollutants -decrease expensive dependence on imported oil -cutting energy waste is the fastest, cheapest, and most environmentally beneficial source of energy
biomass
consists of plant materials such as wood and agricultural and animal wastes that we can burn directly as a solid fuel or convert into gaseous or liquid biofuels- it is an indirect form of solar energy b/c it consists of combustible organic (carbon containing) compounds produced by photosynthesis
In your own words, how is net energy calculated?
net energy is calculated by estimating the total amount of energy available from a resource over its projected lifetime and then subtracting the estimated amount of energy used, automatically wasted because of the second law of thermodynamics, and unnecessarily wasted in finding, extracting, processing, and transporting the useful energy to consumers
What type of energy sources require subsidies to survive in capitalist markets?
nuclear energy and most fossil fuel energy sources such as natural gas, oil, and coal are subsidized by the federal government
The fossil fuels that are often harvested together...
oil and conventional natural gas
Non-renewable energy source(s) that are actually using ancient sun energy...
oil, coal, conventional natural gas, and shale oil
All of the following are disadvantages of using nuclear energy EXCEPT:
on-site air pollution releases
What is energy efficiency?
the measure of how much work we can get from each unit of energy we use. Each unit of energy saved eliminates the need to produce that energy, saving us money
The issue around the Alaskan National Wildlife Refuge (ANWR) is...
the need to find more domestic oil supplies on balance with the health of an area set aside to be a place for wildlife
net energy is:
the total energy available minus the energy needed to find, extract, and process the energy
The aspects of this energy generation shared by wind, hydroelectric, and fossil fuel plants is:
the turbines and the generator
Which of the following negative environmental impacts in NOT associated with coal burning?
waste products must be safely stored for 10,000 years
How much would we reduce our oil consumption and CO2 emissions by switching to more efficient cars?
-2006 DOE study found replacing most of the current US vehicle fleet of 220 million vehicles with highly efficient plug-in hybrid vehicles over 2 decades would cut US oil consumption by 70-90%, eliminate the need for oil imports, save consumers money, and reduce CO2 emissions by 27% -if batteries recharged mostly by electricity generated by renewable resources like wind → 80-90% drop in CO2 emissions
Up to how much energy could we save in homes with proper orientation and insulation?
-2006 UN study → orienting a building to face the sun so it can get more heat from solar energy can save up to 20% of heating costs and up to 75% of such costs when well-insulated/airtight -superinsulated homes in Sweden use 90% less energy for heating and cooling than typical American homes the same size
How many people die every year in the US from fine particle pollution from coal? How many people die every year in China from air pollution?
-24,000 people die prematurely/year in the US from fine particle pollution -in China, 650,000-700,000 people die every year from air pollution
What percentage of global electricity comes from coal? US electricity? Chinese?
-42% of the world's electricity comes from coal -46% of electricity in the US comes from coal -70% of electricity in China comes from coal
Why are Light-Water Reactors so inefficient? Identify at least 3 reasons why.
-75% of the high-quality energy available in their nuclear fuel is lost as waste heat to the environment - additional 9% loss lost from the mining, upgrading, and transportation of uranium -enormous amount of energy (8%) required to deal with radioactive wastes produced by plant -92% inefficient
How do American CAFE standards compare to other countries?
-American CAFE standards for new vehicles much lower than in Europe, Japan, China, and Canada -2008 law raised US CAFE standards to 35mpg to be attained by 2016 → still much lower than other countries
Why are Americans apparently less concerned about fuel economy?
-Americans less concerned about fuel economy b/c they want to drive big, powerful vehicles -most US consumers do not realize gasoline costs much more than what they pay at the pump -2005 study → hidden costs of gasoline is $12 per gallon
How do you think the net energy of conventional natural gas (big underwood pockets) compares to the net energy of natural gas from fracking?
-I think that obtaining natural gas from fracking would have a lower net energy yield than conventional natural gas because fracking requires more energy to extract energy
Why, with such small (or even negative) net energy, is nuclear energy able to compete on the open market?
-The US gov't has provided huge subisidies, tax breaks, and loan guarantees to the nuclear power industry and provides accident insurance b/c insurance companies refuse to fully insure any nuclear reactor
What are some currently available plug-in hybrid models available for sale in the US?
-Toyota Prius Prime, Hyundai Ioniq, Honda Clarity, Kia Niro, Hyundai Sonata, Kia Optima, Subaru Crosstrek Hybrid
What percentage of the world's oil shale do "we" have?
-about 72% of the world's oil shale reserves lie deep in rock formations located primarily in government-owned land in the US states of Colorado, Wyoming, and Utah
Is there enough wind in the US to meet our electrical needs?
-according to a 2009 study published in the Proceedings of the US National Academy of Sciences → US has enough wind potential to meet an estimated 16-22x its current electricity needs
How does active solar heating work?
-active solar heating captures energy from the sun by pumping a heat-absorbing fluid (water/antifreeze) through special collectors usually mounted on a roof/special rocks to face sun -some heat used directly → rest is stored in a large insulated container filled with gravel, water, clay, or heat-absorbing chemical for release as needed
What is wave power?
-almost continuous waves along seacoasts → scientists/engineers trying to tap into wave energy to produce electricity -In Portugal → large, snakelike chains of floating steel tubes insulated off coast → up and down motions of chains by wave action generates electricity -wavepower production limited → fewer suitable sites, high costs, equipment vulnerable to saltwater erosion and storm damage
What is the base material in pv cells?
-base material in pv cells → purified silicon or polycrystallized silicon with trace amounts of metals to allow them to produce electricity
Why does a net energy ratio of less than one mean that there is net energy loss?
-because the amount of energy used to obtain that energy is greater than the amount of energy that you will get out of it
Are biofuels actually carbon neutral?
-biofuels definitely not carbon neutral -fossil fuels used to transport and produce biofuels -corn ethanol used for fuel → worse gas mileage the gasoline -clearing forests/grasslands for biofuel crops increases amount of CO2 in atmosphere
Explain how installing a wind farm and a solar farm would have different impacts on the ability to use land for other purposes at the same time/
-building wind turbines → increased # of transmission lines and power lines → controversy and lawsuits -visual pollution -solar farms are usually in isolated, arid, desert areas where there are usually less people -with wind farms, the land can still be used normally and is fully functional, but with solar farm makes the land virtually unusable
What is conventional natural gas usually found with?
-conventional natural gas is often found with deposits of conventional crude oil trapped together under domes deep within the earth's crust on land or under the seafloor
Identify how much of the crude oil is conventional and how much is unconventional. Reflect how this impacts net energy.
-conventional oil → makes up 30% of the world's estimated supply of oil -unconventional oil → makes up remaining 70% of world's estimated supply of oil
Compare the density of energy in Uranium 235 to that of coal.
-each pellet of enriched uranium-235, roughly the size of an eraser on a pencil, contains the energy equivalent of about a ton (2000lbs) of coal
Why are electric motors wasteful?
-electric motors are wasteful b/c they run only at full speed with their output throttled to match the task - somewhat like keeping one foot on the gas pedal of your car and the other on the brake pedal to control its speed -variable speed motors run at minimum rate needed for each job, saves energy, and reduces the environmental impact of electric motor use
What are some reasons that nuclear power plants are so expensive to build? Given the inefficiency and cost of nuclear power, why do you think it is still so heavily utilized?
-emergency core cooling system, containment shells to to keep radioactive materials from escaping -many working parts and uranium has to be enriched -average cost for a singular nuclear power plant is $14 billion (and rising) -still utilized b/c we have an outdated system and gov't encourages their use with subsidies
How do we use the heat in our crust to heat homes?
-hydrothermal reservoirs of geothermal energy to produce electricity → drilling wells into the reservoirs to extract their dry steam (with a low water content), or wet steam (with a high water content), or hot water, which are then used to heat homes and buildings, provide hot water, grow vegetables in greenhouses, raise fish in aquaculture ponds, and spin turbines to produce electricity.
In what ways could producing biofuels (especially though industrial agriculture) actually increase climate change?
-if nitrogen fertilizers were used to grow corn and other biofuel crops, such fertilizers → release large amounts of potent greenhouse gas nitrous oxide -when this occurs, more greenhouse gases are produced than by burning fossil fuels
What percentage of our oil did we import in the US in 2009?
-in 2009, the US imported 52% of its crude oil at a cost of $200 billion -imported (in order) from Canada, Mexico, Saudi Arabia, Venezuela, and Nigeria
Why don't we pay the same amount for gasoline as European countries?
-in Europe there are gasoline taxes in place to include the real cost of gasoline → unpopular in the US and car/oil companies have managed to prevent gasoline taxes to keep true costs hidden from consumers -in reality, we probably do pay just as much if not more for gasoline than European countries through hidden costs such as gov't subsidies and tax breaks for oil companies, car manufacturers, and road builders, costs of pollution control and cleaning, costs of military protection of oil supplies in the Middle East, time wasted in traffic, illnesses from air and water pollution → higher insurance premiums
List some of the major energy consuming and wasting devices.
-incandescent light bulbs, furnaces, industrial motors, most motor vehicles, coal and nuclear power plants -gas guzzling vehicles and large, poorly insulated homes that require large amounts of energy to heat and cool
List things we can do in existing buildings to save energy:
-insulate the building and plug leaks → adding insulation to walls and attics, plugging air leaks, and sealing heating/cooling ducts are 3 of the quickest, cheapest, and best ways to save money and energy in any building -use energy-efficient windows → insulating effect and lessen heating/cooling costs and reduce heating system CO2 emissions -stop other heating and cooling losses → white/light-colored roofing and sealing leaky heating and cooling ducts -heat houses more efficiently → most efficient ways to improve efficiently and save money: superinsulation, geothermal heat pump that transfers heat stored in the earth to a home, conventional heat pumps, small generating microturbines fueled by natural gas, and a high-efficiency (92-98%) natural gas furnace -heat water more efficiently → roof-mounted solar water heater tankless instant water heater fired by natural gas/LPG -use energy-efficient appliances -use energy-efficient lighting → compact fluorescent light bulbs over incandescent bulbs (4x more efficient and last up to 10x longer)
How are biofuels different from solid biomass?
-liquid biofuels such as biodiesel are produced from vegetable oils and ethanol from ethyl alcohol produced from plants and plant wastes (no animals wastes)
Identify some methods used in efficient, green building.
-makes use of natural lighting, passive solar heating, solar cells, solar hot water heating, recycled wastewater, and energy-efficient appliances and lighting -green roofs covered with soil and vegetation, white/light-colored roofs that reduce cooling costs by reflecting incoming solar radiation -superinsulation → heavily insulated and airtight so there's little need for backup heating systems, even in extremely cold climates
Why might one be able to argue that OPEC is the single most powerful organization in the world?
-many countries' economies around the world depend on oil imports/exports -in the US, much of our foreign policy in the Middle East is based around the fact that we import much of our oil from Saudi Arabia
How is a nuclear power plant similar or different to a coal power plant?
-nuclear power plants are very similar to coal-fired power plants, but one major difference is that nuclear plants uses enriched radioactive materials like uranium to power it
What happens to net energy once it passes peak oil?
-once an oil well passes peak production, net energy begins to decrease because you have to invest more energy in order to get the same return
Briefly describe "feed-in tariff".
-policy designed to accelerate investment into renewable technologies in which households that generate their own electricity from renewable or low-carbon sources and the government may pay you for energy that you generate and export to the National Grid
Summarize the potential environmental impact of creating biofuels from traditional crops like soy, corn, or sugarcane.
-producing ethanol from sugarcane → CO2 emissions from burning oil and gas to produce sugarcane, very high soil erosion after sugarcane harvesting, and high water use/need, contaminated runoff w/herbicides, fertilizers, and pesticides -producing ethanol from corn → net energy yield of 1.1-1.5% (low) and increases food prices in US, Mexico, and other countries, potential increase in CO2 emissions -producing biofuel from soy → 2009 studies found clearing Brazilian rain forests to grow soybeans for fuel would create a loss of carbon uptake that would take more than 300 years to replace
cogeneration
-production of two useful forms of energy, such as high temperature heat or steam, and electricity, from the same fuel source CHP production (combined heat and power) -steam produced in generating electricity in a CHP system can be used to heat the power plant and other nearby buildings, rather than released into the environment and wasted -energy efficiency → 75-90% (compared to 30-40% for coal-fired boilers and nuclear power plants), emit 1/3 CO2/unit energy produced as coal-fired boilers
What are some benefits of converting coal to liquid or gas?
-synthetic natural gas (SNG) → coal gasification (removes sulfur and other impurities from coal) -coal liquefaction → synfuels (produce less air pollution, but lower net energy yield) -synthetic fuels have lower net energy yield, are more expensive to produce, and require large amounts of energy
Passive solar heating system
-system absorbs and stores heat from sun directly within a well-insulated structure -walls and floors of concrete/adobe/brick/stone and water tanks store collected solar energy as heat, then release it slowly throughout day/night -white/light-colored roofing reduces overheating -heavy insulation, superwindows, vent that allows hot air to escape during the summer
Describe the contribution that wind power makes to your energy production.
-the US is the 2nd largest wind power producer (China is the first) and wind power is the second fastes growing source of energy worldwide (solar 1st)
What's the "smartest" way to heat a home based on net energy? The least?
-the best way to heat a home based on net energy is passive solar heating (5.8) followed by natural gas (4.9) -the least effective/worse way to heat a home based on net energy is electric heating from a nuclear plant
What factor does the book identify as being the primary determiner of our future energy path?
-the energy path we choose depends primarily on what energy resources the government and private companies decide to promote, which will be influenced partly by political and economic pressure from citizens and consumers
Respond to the last paragraph on pg. 431
-the paragraph makes me hopeful for the future in that every individual can at least do something to help make a change
What is the primary reason coal is so cheap?
-the primary reason coal is a relatively cheap way to produce electricity is that most of its harmful environmental and health costs are not included in the market price of electricity from coal-burning power plants
Hydropower might sounds great. But what are some of the disadvantages that you leaned in this section that are new?
-the world's largest dams are together the single largest human-caused source of methane due to the decomposition of submerged vegetation in hydropower plant reservoirs, especially in warm climates -mountain glaciers melting → primary water source for dams → projected climate change likely to reduce electrical output
What is important to pay attention to, if we want to make sure that hydrogen fuels don't lead to climate change?
-using electricity from coal-burning power plants and nuclear power plants to decompose water into H2 and O2 as well as making H2 from coal and stripping it from organic compounds do not avoid harmful environmental effects -renewable energy sources needed to be used to produce H2 if we want to avoid CO2 emissions
In what way does recycling save energy?
-using recycled materials saves money and energy -producing steel from recycled scrap iron uses 75% less energy than producing steel from virgin iron ore and emits 40% less CO2 -switching 3/4 of world's steel production to such furnaces would cut energy use in the global steel industry by almost 40% and reduce CO2 emissions
What is tidal power?
-water levels in coastal bays/estuaries can rise/fall by 20ft or more daily → dams built across mouths of some bays/estuaries to capture energy in tidal flows for hydropower -only 2 large tidal energy plants operating → La Rance, France and Nova Scotia's Bay of Fundy
What can't we control about net energy? What can we control? What percentages of energy use do each of these represent?
-we can't control net energy because according to the second law of thermodynamics, some energy is automatically lost/wasted -we can however try to use energy sources with net energy yields that are as high as possible and try to minimize waste through transportation, mining, etc. -41% of all commercial energy is automatically wasted due to 2nd law of thermodynamics -Americans then unnecessarily waste 43% of all energy (totaling 84% wasted)
When hydrogen is used in a fuel cell, or combusted, what is released?
-when hydrogen is used in a fuel cell, hydrogen and oxygen react and water vapor and energy is released
How is a photovoltaic cell (PV) different from a solar thermal system?
-when sunlight strikes cells, they emit electrons and many cells wired together can produce electricity → cells can be connected to existing electrical grid systems/batteries that store electricity until needed -can be mounted on rooftops or incorporated into roofing material that can be installed on basically any surface -typical solar cell is as thick as a human hair to that of a sheet of paper
Wind turbines are enpensive(ish). Explain how wind could be considered the cheapest form of energy.
-wind is widely distributed and inexhaustible -mostly carbon-free and pollution free -wind farm can be built in 9-12 months and expanded as needed -when harmful environmental and health costs of various energy resources included as compared to wind energy, it may be cheapest way to produce electricity
How have engineers reduced the risk of bird mortality with wind trubines?
-wind power developers make sophisticated bird migration studies so they can avoid building in the way of them -newer wind turbines have slower blade rotation speeds and do not provide places for birds to perch/nest to reduce bird casualties
List the three advantages for using biofuels.
1. biofuel crops can be grown almost anywhere and thus they help countries decrease dependence on imported oil 2. if crops not used faster than they're replenished by new plant growth, no net increase in CO2 emissions 3. biofuels are available, easy to store and transport, can be distributed through existing fuel networks, and can be used in motor vehicles at little/no additional cost
List four things that we can do "naturally" to keep buildings cool.
1. block high summer sun w/window overhangs, awnings, or shades 2. warm climates → use light-colored roof to reflect up to 90% of the sun's heat (only 10-15% w/dark roof) 3. use geothermal heat pumps for cooling (and heating during winter) 4. open windows to take advantage of breeze, use fans to circulate air, implement a living roof to keep a building cooler
How energy efficient (or inefficient) are the four widely used devices?
1. incandescent light bulb → 5-10% electricity used is for producing light, other 90-95% is wasted as heat (fluorescent bulbs are much more efficient) 2. internal combustion engine → waste about 80% of energy in its fuel 3. nuclear power plant to produce electricity → wastes 75% of energy in its nuclear fuel and closer to 92% when we include additional energy used in the nuclear fuel cycle 4. coal-fired power plant → wastes 66% energy that is released by burning coal to produce electricity → probably 75-80% if we include energy used to dig up/transport coal and store toxic ash byproduct
What are three things that the government can do to support consumers choosing renewable energy?
1. keep the prices of selected energy resources artificially low to encourage the use of those resources (tax breaks, subsidies, and loans to encourage renewable energy resources) 2. keep the prices of selected energy resources artificially high to discourage their use (fossil fuels) eliminating subsidies and tax breaks) 3. governments can encourage/emphasize consumer education
What are some limitations to solar thermal systems?
1. power plants require large volumes of water for condensing steam back to water for reuse and washing off surfaces of mirrors/parabolic troughs 2. thermal power plants often built in sunny, arid areas where water is scarce 3. wet-cooling system → some water must constantly be replenished b/c it evaporates and is released into atmosphere 4. dry-cooling systems → uses fans and heat exchangers to transfer excess heat to atmosphere, but this lowers the net energy yield of the whole system and raises the cost of electricity produced 5. solar thermal systems have a low net energy yield of 3%
Identify 3 ways in which a Smart Grid is more efficient than the old grid.
1. smart meters would also show consumers how much energy they are using by the minute for each appliance → info to help reduce power consumption and bills 2. consumers who use solar cells, wind turbines, or other devices to generate some of their own electricity could cut their bills by selling excess electricity to utility companies 3. smart appliances can be programmed to run during off-peak hours when electricity is cheaper and run air conditioners remotely (leave them off when not at home, turn on before returning home)
List two ways that excess electricity can be stored for cloudy days or night time electricity needs.
1. use excess electricity to run pumps that compress air into underground caverns → pressure released as needed to drive turbines and produce electricity 2. excess energy can be stored by using the electricity to decompose water and produce hydrogen gas to be used as fuel
Compare biodiesel to ethanol- what type of liquid, how they are made and what they are made from, how they are used?
BIODIESEL: -produced from vegetable oil extracted from soybeans, rapeseed, sunflowers, oil palms, jatropha shrubs, and coffee grounds -used for diesel fuel for cars (diesel 40% more efficient than gasoline engines) ETHANOL: -can be made from sugarcane, corn, and switchgrass from agricultural, forestry, and municipal wastes -converting plant starches into simple sugars used to produce ethanol -used mostly for car fuel
What are the pros and cons of burning biomass for energy?
CONS: -biomass plantations → fast-growing trees such as cottonwoods, willows, poplars, shrubs, switchgrass, water hyacinths → repeated cycles depletes soil nutrients -clearing forests/grasslands for biomass plantations destroys/degrades biodiversity -plantation tree species (European poplar, American mesquite) → invasive species that can take over nearby ecosystems -clearing forests → reduces vegetation that would otherwise capture CO2 -burning biomass produces CO2 and is only 30-40% efficient PROS: -using cogeneration system raises net energy yield of burning biomass to 60% or higher
What are the pros/cons of offshore wind power?
CONS: -more costly to install PROS: -wind speed over water are stronger and steadier than on land -noise muffled by surf sounds → avoid noise complaints by people living near land-based wind farms -offshore wind → eliminates need for negotiations among landowners over locations of wind turbines and electrical transmission lines -more suitable locations at sea, turbines can be anchored on floating platforms out of sight of coastal residents
What are CAFE standards?
Corporate Average Fuel Economy standards -U.S. gov't fuel efficiency standards for motor vehicles -average fuel efficiency in the US has improved 3mpg since 1908 (Ford model T)
What is the difference between a hybrid car and a plug in hybrid electric?
HYBRID CAR -small, traditional gasoline-powered engine and a battery powered electric motor used to provide the energy needed for acceleration and hill climbing -Toyota Prius → combined city-highway mileage of up to 50mpg and emit 65% less CO2/km driven than comparable conventional car emits PLUG-IN HYBRID VEHICLE -hybrid w/a second, more powerful battery that can be plugged into an electrical outlet and recharged → 100mpg for ordinary driving and up to 1000mpg if only used for trips of less than 40 miles before recharging
Would passive solar heating be appropriate for where we live? Explain., How about Seattle?
I do think that California in general would be suitable for passive solar heating as it is sunny more often than not and we live in a generally dry climate. Seattle on the other hand, may not be as well off w/passive solar heating b/c they have often gloomy, cloudy, rainy weather
What do you think will be the greatest disadvantage or hindrance to implementing wide scale wind power?
I think the biggest hindrance to implementing wide scale wind power is opposition by people who don't want wind turbines on their properties/areas (NIMBY)
Briefly describe the Nuclear Fuel Cycle beyond the nuclear power plant.
NUCLEAR FUEL CYCLE: -mining of uranium, processing and enriching it to make fuel, using it in a reactor, and safely storing the resulting highly radioactive wastes, in the form of depleted or spent fuel rods, for thousands of years -dismantling highly radioactive reactors at the end of their useful lives and safely storing their radioactive components for thousands of years -each step in nuclear fuel cycle adds to the cost of nuclear power and reduces its net energy yield
Remind yourself of the pros and cons of dams.
PROS: -reduces downstream flooding of cities/farms, can produce cheap electricity, reservoir useful for recreational activities, provides drinking water, provides irrigation water above and below dam CONS: -flooded land destroys forests/croplands and displaces people, large losses of water through evaporation, deprives downstream cropland and estuaries of nutrient-rich silt, risk of failure and devastating downstream flooding, disrupts migration and spawning of some fish
How can we use sunlight to drive a generator?
SOLAR THERMAL POWER -curved solar collectors concentrate solar energy and use it to produce electricity -concentrated solar energy heats a fluid-filled pipe that runs through the center of each trough → concentrated heat in fluid used to produce steam that powers a turbine that generates electricity
Petroleum or crude oil can be refined using different bioling points into petrochemcial products including all the following EXCEPT:
charcoal, computer chips, and ceramics
Why is energy efficiency such an important energy source?
energy efficiency is an important source because it is a largely untapped source of energy that is abundant, clean, cheap, and readily available. We could save money by it → lowering utility and gasoline bills, improve military and economic security by reducing/eliminating dependence on foreign oil, and sharply reduce our greenhouse gas emissions which contribute to projected climate change
Electrical energy is generated by kinetic energy moving a turbine, which then works a generator...
hydropower, windmills, and a geothermal steam power plant
All of the following are true of oil shale EXCEPT:
it has a high net energy
the benefits of using anthracite, a hard coal, verses other softer coal such as bitumous include:
it has a lower sulfur content
What are two ways to liquefy natural gas? What happens to net energy when it is liquefied? What is the benefit to doing this?
liquefied petroleum gas (LPG): -when a natural gas field is tapped, propane and butane gases are liquefied under high pressure and removed as liquefied petroleum gas -LPG stored in pressurized tanks for use in mostly rural areas not served by natural gas pipelines liquefied natural gas (LNG): -natural gas can be converted to liquefied natural gas at a high pressure and very low low temperature (-260 degrees F) -highly flammable liquid can be transported overseas in refrigerated tanker ships then heated and converted back into gaseous state for distribution by pipeline once it reaches destination (low net energy)