Energy

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Arctic National Wildlife Refuge

19 million acre (7,689,300 hectare) wilderness area and wildlife refuge stretching from the shore of the Beaufort Sea across the Brooks Range through the tundra and into the boreal forest of interior Alaska

energy sources

Nuclear and hydroelectric: largest source of renewable electricity in US. - remained unchanged in recent years but other renewables like biomass, geothermal and solar have increased nearly 10%. largely driven by the increase in wind energy the carbon content of natural gas is lower and, therefore, less is emitted during combustion compared to coal

oil

Oil and natural gas are formed primarily from tiny sea organisms that are able to photosynthesize like plants. These sea creatures die and collect on the sea floor, sediment accumulates above them, and enormous heat and pressure eventually transform these organisms into oil and natural gas. Oil and natural gas are stored in the pore spaces and folds within rock, and are often found together. a product with a great many uses, ranging from being a component of synthetic fibers (for example, nylon) to a major ingredient in almost all types of plastic. oil becomes a hugely important liquid fuel for all types of motors and engines.

Tidal and ocean

Tidal and ocean power taps into thermal energy from the Sun and the mechanical energy from tides, waves, and currents near coastlines. The potential for tidal and ocean power is great, however, because the ocean and tides are always in action. Currently, only a handful of these projects exist, mostly in Europe

coal

US has more coal than all other countries in the world. It has nearly 28% of the world's known coal reserves, mined in 26 states. Every day the average American uses several tons of coal. Its primary use is to produce electricity which powers many household appliances.

nuclear power

can be generated through fission and fusion. only nuclear fission *(splitting of atomic nuclei (of heavy atoms) by bombarding them with neutrons)* is currently used for electricity generation. Uranium (or more specifically, U-235, a fissile isotope of uranium) is used for electricity generation. In order to be used in a reactor, naturally occurring uranium is enriched so that it contains 3% U-235 instead of 0.7%

For an industry that needs both electricity and steam to power equipment, which of the following would be a good way to make efficient use of energy?

cogeneration

If the United States decided to significantly increase the production of biofuels and their reliance on them as a fuel source, which of the following is least likely to result?

decrease in cost of food items...

Most of the natural gas consumed in the United States is used by which of the following sectors?

electric power

Petroleum is to transportation as natural gas is to:

electricity generation.

The largest portion of renewable energy in the United States comes from:

hydroelectric projects.

renewable energy types

hydropower, biomass, wind, solar, geothermal, biofuels, wave/tidal

oil uses

important liquid fuel for all types of motors and engines. petroleum use has increased dramatically due to the transportation sector. The transportation sector alone is the largest consumer of petroleum products in the United States.

renewable energy sources

include hydropower, ocean and tidal, solar, and wind sources along with some geothermal sources. capable of naturally replenishing themselves at a rate equal to or greater than the rate at which we use them --> regenerative or nearly inexhaustible.

Cogeneration

is the production of electrical energy and another form of useful energy, such as heat or steam, through the sequential use of energy.

Geologists discover oil off the coast of an island in the Pacific Ocean. When estimating the total amount of technically recoverable oil, they state that "there is a 95% probability that at least 3.9 billion barrels of oil are recoverable, and there is a 5% probability that at least 12 billion barrels of oil are recoverable." Which of the following is true about the amount of economically recoverable oil at this same location?

it will depend on the price

types of coal ranked from least to greatest E produced

lignite, subbituminous, bituminous, and anthracite most abundant, softest, and youngest type of coal is lignite, while the least abundant, hardest, and oldest form of coal is anthracite

technically recoverable

meaning they are in place and recoverable, but with no regard to cost

economically recoverable

meaning they are in-place and recoverable at a cost which is feasible

in-place

meaning they are there, but not necessarily recoverable

Many of the challenges currently faced by the nuclear industry are in part a result of a history that includes:

mismanagement and a poor understanding of the associated risks.

Electric cars are touted as a cleaner form of transportation with less associated greenhouse gas emissions. At this time, most of our electricity, which powers these cars, comes from:

natural gas.

In the United States, the implementation of large-scale wind turbines to meet the demand of the countries electricity needs is most limited by the:

need for appropriate transmission systems

Many cities' sustainability plans for energy grow primarily out of a concern for:

reducing greenhouse gas emissions.

fission

releases three neutrons, fission fragments (nuclei of other radioactive elements), and heat energy. Once released, the neutrons collide with other U-235 atoms and so on. This self-perpetuating process is referred to as a chain reaction. When this chain reaction occurs in a controlled and sustained manner, such as that produced in a nuclear reactor, it can be used as a heat source for electricity generation.

While much has improved when it comes to both small- and large- scale solar energy systems, according to your lesson, __________ is still a limiting factor

the number of suitable sites?

fossil fuel formation

"Fossil fuels were formed from plants and animals that lived 300 million years ago in primordial swamps and oceans [left]. Over time the plants and animals died and decomposed under tons of rock and ancient seas [middle]. Eventually, many of the seas receded and left dry land with fossil fuels like coal buried underneath it [right]. Ten feet of prehistoric plant debris was needed to make one foot of coal."

Energy consumption & production in the US

(from greatest to least) Petroleum natural gas coal nuclear biomoass other renewables hydroelectric Domestic sources far exceed foreign sources, as you already saw in the chart above. Since 2000 our consumption has remained relatively unchanged (slight variations from year to year), while domestic energy production has by and large increased and imports have decreased.

electricity drawbacks

- can be very dirty to generate - transmission over long distances can be inefficient and wasteful - cannot be stored in large amounts--with current the infrastructure, electricity generated from any source has to be used relatively quickly after it has been produced

nuclear power uses

The sole end use sector of nuclear power is electric power. About 20% of United States electricity was generated using nuclear power.

energy

describes the ability to do work

renewable energy benefits

- clean source of electricity - can exist on large and small scales, even for just one home or village - demand on the environment and other resources is less - fuel supply is domestic and virtually limitless

electricity benefits

- clean--no emissions or pollution associated with electricity itself - infinitely flexible in applications

renewable energy sources

1.) conventional hydroelectric power 2.) biofuels 3.) wind

Which of the following statements correctly describes ethanol and methane?

Ethanol is a derivative of biomass, while methane is the main constituent of natural gas.

biofuel

biomass resources can also be converted into biofuels, which are used as alternative/replacement transportation fuels. Ethanol, methanol, biodiesel, and additives for reformulated gasoline are all examples of biofuels.

In an industrializing or newly industrialized country, __________ is most often replaced by ___________ as the primary energy source.

biomass; coal

energy efficiency and conservation

total consumption per American has generally increased over the past 50+ years, consumption per dollar of gross domestic product has dramatically decreased One of the ways to increase the efficiency of the processes we currently employ is through cogeneration (or combined heat and power). Cogeneration is the production of electrical energy and another form of useful energy, such as heat or steam, through the sequential use of energy.

Technologies used to capture / harness sunlight :

*Photovoltaics* (also called solar cells) convert sunlight directly into electricity. Photovoltaic cells absorb sunlight, which disturbs electrons in the cell and knocks them loose. These electrons flow through the photovoltaic material and produce electricity. Small photovoltaic arrays can produce electricity for individual homes and buildings, while large arrays might one day produce electricity at the power plant scale. *Passive solar *technologies exploit solar energy for heating, cooling, and lighting with large, south-facing windows; flooring or wall materials that absorb solar energy during the day and release its heat at night (called direct gain); incorporating wall and roof angles that optimize solar exposure; and designing natural ventilation systems for cooling. Passive solar designs can reduce heating bills for a building up to 50%! *Solar thermal *systems use solar heat to produce electricity. A large arrangement of mirrors divert and focus sunlight onto a single point, creating a high-intensity heat that can produce steam or mechanical power and turn a generator. *Solar hot-water heaters *use the sun's energy to heat water or a heat-transfer fluid, both of which are kept in solar collectors mounted on a building. Many times the heated water is pumped directly to a swimming pool, where the pool itself becomes a storage tank. A typical solar hot water system can offset need for conventional water heating in a building by roughly 60%.

Biomass benefits

- renewable on a human timescale - bioenergy feedstocks can benefit rural/farming communities - a home-grown (domestic) source/resource - many different sources of biomass that can be used many different ways to produce energy - can use organic byproducts that are usually considered waste - generates fewer emissions than fossil fuels - reduces the amount of waste sent to landfills

biomass drawbacks

-carbon-based, so when burned still releases carbon dioxide; unlike fossil fuels, however, biomass does not add permanently to atmospheric carbon dioxide levels as newly planted biomass crops take in carbon dioxide from the atmosphere - burning may cause respiratory problems (this is a significant problem where wood is burned indoors for food preparation or warmth) - efficiencies of bioenergy generating systems still need improvement - cost of bioenergy is not yet cost-competitive with fossil fuels

fossil fuel benefits

- flexible, many uses from auto fuel to electric power - readily available inside the United States - already accounts for a great deal of United States energy usage--tough to switch to something else quickly

renewable energy drawbacks

- front-end costs including transmission lines and new/upgraded infrastructure can be significant - sites of greatest potential might be difficult to access and/or not connected to where the energy is needed - wind turbines and farms may be competing with more profitable land uses in areas with high wind potential - fuel sources are often intermittent and supply cannot be controlled (that is, the wind is not always blowing and the sun is not always shining) - potential disruptions to wildlife including bats and birds (wind, mainly with older turbines) - as with all electricity sources, surpluses cannot be stockpiled

fossil fuel drawbacks

- highly polluting--major source of carbon, sulfur, mercury, and nitrogen emissions - supplies of some fossil fuels, like crude oil, are unquestionably diminishing and will become more expensive - extraction can be environmentally damaging (think: Deepwater Horizon disaster, mountaintop coal removal) and politically/socially disastrous (think: first and second Gulf Wars in Iraq)

nuclear power drawbacks

- nuclear fission uses & produces radioactive isotopes, which are released throughout nuclear cycle (from mining to disposal) - hazards are associated with the transport & disposal of nuclear fuel & waste - unwanted chemical reactions can occur in a reactor that may produce explosions & release radioactive material into the environment - history of accidents involving nuclear power plants (for example, Three Mile Island in 1979, Chernobyl in 1986, and Fukushima in 2011) - uncertainty as to what to do with retired or non-operational reactors - global concern about nuclear fuels being obtained for non-electricity generating purposes

Which of the following is NOT considered a benefit of biomass used as a source of energy?

Biomass is cheaper than fossil fuels.

Coal Formation

Coal formed from the remains of vegetation--trees, ferns, mosses, and other plant matter--that lived millions of years ago. Around 300 million years ago (during the aptly named the Carboniferous period), the earth was covered by forest and sea, at times the forests flooded becoming wet and swampy. As plants died and began to decompose, they became buried under dense layers of wet, dense earth, and exposed to heat and pressure. After the seas dried up, a high sulfur coal like that mined in the eastern United States today, formed

In effort to reduce air pollution and harmful emissions, it would be most preferred to burn coal from:

Montana.

Biopower

Most biopower is generated using direct combustion, which involves burning biomass resources to produce steam

Solar power

Sunlight can be captured and used to meet a variety of energy needs, from generating electricity and heating water to cooling and lighting buildings Solar energy technology has provided people living in marginal areas with a cleaner, more reliable, and safer energy source than they have relied on in the past (biomass and kerosene, mostly). Small-scale solar power is also more popular than ever in the United States driven by falling prices and increased accessibility of roof-top solar panels.

wind power

The wind's kinetic energy is converted to mechanical power by wind turbines recent estimates made by the National Renewable Energy Laboratory project that wind has the potential to supply as much as nine times the country's current electricity consumption! midwest and great plains have highest wind speeds in the country

What do Residential, Industrial & Commercial, and Transportation represent in the flow chart above?

These are the three primary end-use sectors, in other words, the category of the economy that will ultimately consume a fuel source. As you read through this lesson, consider the end-use sector for each fuel type. Keep in mind that electricity generation is NOT an end-use sector, rather it is a secondary source of energy

wind mechanical power can be used in 3 ways

Wind-derived mechanical power can be used directly to grind grain or pump water (for people, animals, or irrigation). Once converted to electricity, wind energy can be used at a small, localized scale to power small appliances or telecommunications networks. At a large scale, utilities can use massive wind turbines to generate electricity for many homes and businesses. A large number of closely placed turbines can be used by homeowners, farmers, or utility companies to generate electricity. Such clusters of wind turbines are called wind farms.

According to your lesson, the ultimate cause of the disaster at Chernobyl was:

a poor understanding of nuclear technology's risks.

All of the following statements describe both biomass and fossil fuels, EXCEPT

accounts for a large portion of energy consumed in the United States.

energy types

biomass: plant resources - consumption of wood as fuel for heating purposes coal was found to be more efficent so then came the era of buring --> fossil fuels: burning coal & natural gas directly provides the energy needed to power vehicles, heat homes and water, cook food, produce common materials from plastics to textiles. main source of energy to generate electricity (through nuclear and renewables like wind, hydro, and solar power.)

domestic sources of coal

coal found in the western United States (for example, Wyoming) has a lower sulfur content than coal found in the eastern United States (for example, Pennsylvania lots of coal mined in Wyoming

natural gas uses

consumption was dominated by the industrial sector. However, over the past few years, the amount of natural gas used by the industrial sector has plateaued, while use by the electric power sector has caught up. Today in terms of natural gas consumed the electric power sector (34%) and the industrial sector (35%) are pretty evenly matched.

electricity generation by source

electricity does not exist independently (except as lighting, static, et cetera electricity is a product of other energy sources: a power plant burns fossil fuels, nuclear fuel, or biomass to produce heat and boil water. The steam produced is used to drive turbine generators which produce electricity. The process just described is known as *generation.* The electricity is then sent from the power plant along high-voltage* transmission* lines to factories, large buildings, or neighborhoods, where it is converted to lower voltage electricity for *distribution* to homes and businesses. This entire chain from generation all the way to delivery to the customer is known as the *electricity grid *and it is no less than a modern marvel.

ethanol - biofuel that seems to be the best because:

employs farmers and workers at ethanol refineries, not to mention truckers and pipeline companies shipping the fuel around the country; reduces the import of crude oil from other countries, which not only limits the potential for a big spill in the ocean, but cuts some of the close ties with repressive governments in Latin America, Africa, and the Middle East; shrinks the need to extract crude oil from land and water sites in the United States, eliminating the potential for another disaster like 2010's Deepwater Horizon explosion in the Gulf of Mexico; and is closer to being carbon-neutral than regular gasoline and diesel fuels. can be produced from a number of sources, including corn, sugar cane, and increasingly, certain types of fast-growing grasses

environmental impacts of energy use

fossil fuels account for 80% of the energy consumed in the United States. Burning fossil fuels releases a number of toxic substances into the atmosphere and hydrosphere, like sulfur, nitrogen, and mercury. Both sulfur and nitrogen can combine with water vapor to produce sulfuric and nitric acid, which may fall as acid rain, severely damaging forests and even buildings. Global climate change is also linked to energy consumption through the release of methane, nitrous oxides, and carbon dioxide Significant sources of these emissions include coal mining; natural gas production, processing, and distribution; and combustion in passenger cars. 93% of United States emissions come from the combustion of fossil fuels, and a significant proportion of that from the transportation sector energy sources are not infinite.

hydropower

generated by water falling from a higher position to a lower position (naturally or over a dam). As the water falls, it can turn turbine blades in a generator to produce electricity. supplies roughly one-quarter of the world's electricity overall contribution has diminished over the years, but it nevertheless remains the primary component of renewable energy in the United States

geothermal energy

in the form of heat, originates deep within the Earth and is conducted through the crust towards the Earth's surface As magma (very hot, molten rock) rises to the crust from deep within the Earth, it brings hot material closer to the surface. As magma cools, it transmits heat to the surrounding materials (rock or water). supplies a small portion, less than 1%, of electric power in the United States every year ranks last behind hydropower, biomass, solar, and wind. conditions are optimal for tapping into geothermal energy in areas of current or recent volcanic/magmatic activity, such as that found along continental plate boundaries. California and Oregon, home to the Cascade Volcanic Arc.

In your lesson you were shown a flow chart of energy flows in the United States. According to that chart and the information presented, in the United States:

most of the energy consumed is from domestic sources.

natural gas

mostly methane. It burns without by-products like ash and creates much less air pollution than either coal or oil. The United States has significant natural gas deposits with proven reserves in roughly 30 states Middle East also has the world's largest deposits of natural gas

You are asked to consult on a new design for an office building in East Lansing. The architects want to focus on clean energy and reducing energy costs. You recommend that the architects _________________ because it is relatively simple to incorporate during the building process and can reduce heating bills by up to 50%.

passive solar design

Nuclear power benefits

powered by a finite mineral substance (uranium) like fossil fuels -- not considered renewable. Nevertheless it avoids many of the problems associated with fossil fuels -> nuclear power is considered an emission-free source of energy (only water vapor is released from cooling towers) and its associated wastes are containable and manageable, even if they are extremely toxic and potentially dangerous. - relatively low impact on the environment, especially in relation to kilowatts produced - emission-free - requires a relatively small area - efficient electricity generation, which is cost-effective - uncontrolled chain reactions cannot occur in a reactor - nuclear technology and monitoring and public awareness have been increased and improved as a result of past accidents

biomass

refers to all non-fossil organic materials, which by nature contain stored solar energy that can be converted to other forms of energy. converted by burning or directly converted to liquid biofuels in order to be burned as fuels. Biomass resources include any organic materials available on a renewable basis (that is, they can be replaced at a rate equal to or greater than the rate at which we use them) ex:] wood and wood wastes, agricultural crops and their waste byproducts, municipal solid waste, animal wastes (manure), waste from food processing, and aquatic plants and algae are all considered and currently used as biomass resources.

Geothermal heat pumps

take advantage of the relatively constant temperatures of the earth just beneath its surface. Geothermal heat pumps transfers heat from the earth to a building during the winter, and transfers heat from buildings to the earth in the summer. Heat extracted can also be used directly to heat water in hot water heaters.

fossil fuels

those formed in the Earth from the remains of once-living organisms (flora and fauna). source of energy that can be used when burned or combusted. oil (or petroleum), natural gas, coal, and fuels derived from oil and gas shales; they differ based on their initial organic material, as well as what happened to that material after it died and was buried. dominant source of energy use in US & worldwide

electricty gen. rule

while electricity has fewer associated emissions than the combustion of fossil fuels, electricity is a secondary source of energy that must come from a primary source. It is the primary source, then, that determines the environmental and health benefit of electricity at any one location. In one location, where electricity in the region is generated primarily from a hydroelectric dam or wind turbines, the benefit of using electricity is significant, while in another area, where a coal power plant is the primary source of electricity, the benefit is negated.


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