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5729317d6aef051400154b5f
What forces measurement attempts to choose between trade-offs, in quanta?
either-or nature of uncertainty
[ "Planck_constant\n\nwhere the uncertainty is given as the standard deviation of the measured value from its expected value. There are a number of other such pairs of physically measurable values which obey a similar rule. One example is time vs. energy. The either-or nature of uncertainty forces measurement attempt...
5729317d6aef051400154b60
What form do measurement attempt trade-offs for quanta take the form of?
either-or (as in Fourier analysis)
[ "Planck_constant\n\nwhere the uncertainty is given as the standard deviation of the measured value from its expected value. There are a number of other such pairs of physically measurable values which obey a similar rule. One example is time vs. energy. The either-or nature of uncertainty forces measurement attempt...
57296f9aaf94a219006aa40d
How is uncertainly measured in this experience?
the standard deviation of the measured value from its expected value
[ "Planck_constant\n\nwhere the uncertainty is given as the standard deviation of the measured value from its expected value. There are a number of other such pairs of physically measurable values which obey a similar rule. One example is time vs. energy. The either-or nature of uncertainty forces measurement attempt...
57296f9aaf94a219006aa40e
What type of analysis fits the either-or nature of the uncertainty?
Fourier analysis
[ "Planck_constant\n\nwhere the uncertainty is given as the standard deviation of the measured value from its expected value. There are a number of other such pairs of physically measurable values which obey a similar rule. One example is time vs. energy. The either-or nature of uncertainty forces measurement attempt...
57296f9aaf94a219006aa40f
What example is given as another paired relationship of uncertainly related to standard deviation?
time vs. energy
[ "Planck_constant\n\nwhere the uncertainty is given as the standard deviation of the measured value from its expected value. There are a number of other such pairs of physically measurable values which obey a similar rule. One example is time vs. energy. The either-or nature of uncertainty forces measurement attempt...
5729703b1d0469140077945b
What is the unit of magentic properties of the electron?
Bohr magneton
[ "Planck_constant\n\nThe Bohr magneton and the nuclear magneton are units which are used to describe the magnetic properties of the electron and atomic nuclei respectively. The Bohr magneton is the magnetic moment which would be expected for an electron if it behaved as a spinning charge according to classical elect...
5729703b1d0469140077945c
What is the unit of magentic properties of atomic nuclei?
nuclear magneton
[ "Planck_constant\n\nThe Bohr magneton and the nuclear magneton are units which are used to describe the magnetic properties of the electron and atomic nuclei respectively. The Bohr magneton is the magnetic moment which would be expected for an electron if it behaved as a spinning charge according to classical elect...
5729703b1d0469140077945d
The Bohr magneton is the magnetic moment of an electron under what restriction?
behaved as a spinning charge according to classical electrodynamics
[ "Planck_constant\n\nThe Bohr magneton and the nuclear magneton are units which are used to describe the magnetic properties of the electron and atomic nuclei respectively. The Bohr magneton is the magnetic moment which would be expected for an electron if it behaved as a spinning charge according to classical elect...
5729703b1d0469140077945e
What three terms define the Bohr magneton value?
the reduced Planck constant, the elementary charge and the electron mass
[ "Planck_constant\n\nThe Bohr magneton and the nuclear magneton are units which are used to describe the magnetic properties of the electron and atomic nuclei respectively. The Bohr magneton is the magnetic moment which would be expected for an electron if it behaved as a spinning charge according to classical elect...
572970db6aef051400154ec4
How was the Planck constant calculated in the early 20th century?
the Planck constant could be determined by examining the spectrum of a black-body radiator or the kinetic energy of photoelectrons
[ "Planck_constant\n\nIn principle, the Planck constant could be determined by examining the spectrum of a black-body radiator or the kinetic energy of photoelectrons, and this is how its value was first calculated in the early twentieth century. In practice, these are no longer the most accurate methods. The CODATA ...
572970db6aef051400154ec5
The value quoted here for the Planck constant is based on a measurement in what year?
2007
[ "Planck_constant\n\nIn principle, the Planck constant could be determined by examining the spectrum of a black-body radiator or the kinetic energy of photoelectrons, and this is how its value was first calculated in the early twentieth century. In practice, these are no longer the most accurate methods. The CODATA ...
572970db6aef051400154ec6
Where was this measurement made?
the U.S. National Institute of Standards and Technology (NIST)
[ "Planck_constant\n\nIn principle, the Planck constant could be determined by examining the spectrum of a black-body radiator or the kinetic energy of photoelectrons, and this is how its value was first calculated in the early twentieth century. In practice, these are no longer the most accurate methods. The CODATA ...
572970db6aef051400154ec7
What method was was used to obtain the measurement?
watt-balance measurement
[ "Planck_constant\n\nIn principle, the Planck constant could be determined by examining the spectrum of a black-body radiator or the kinetic energy of photoelectrons, and this is how its value was first calculated in the early twentieth century. In practice, these are no longer the most accurate methods. The CODATA ...
572970db6aef051400154ec8
One other measure involved the molar volume of what element?
silicon
[ "Planck_constant\n\nIn principle, the Planck constant could be determined by examining the spectrum of a black-body radiator or the kinetic energy of photoelectrons, and this is how its value was first calculated in the early twentieth century. In practice, these are no longer the most accurate methods. The CODATA ...
572971471d0469140077946d
What is a main practical difficulty in determining n?
the two most accurate methods, the watt balance and the X-ray crystal density method, do not appear to agree with one another
[ "Planck_constant\n\nThere are both practical and theoretical difficulties in determining h. The practical difficulties can be illustrated by the fact that the two most accurate methods, the watt balance and the X-ray crystal density method, do not appear to agree with one another. The most likely reason is that the...
572971471d0469140077946e
Why does this difficulty occur?
it is (or they are) not as precise as is currently believed
[ "Planck_constant\n\nThere are both practical and theoretical difficulties in determining h. The practical difficulties can be illustrated by the fact that the two most accurate methods, the watt balance and the X-ray crystal density method, do not appear to agree with one another. The most likely reason is that the...
572971471d0469140077946f
Which method is at fault or the discrepancy?
there is no indication which method is at fault
[ "Planck_constant\n\nThere are both practical and theoretical difficulties in determining h. The practical difficulties can be illustrated by the fact that the two most accurate methods, the watt balance and the X-ray crystal density method, do not appear to agree with one another. The most likely reason is that the...
572971e61d04691400779473
Other than the X-ray crystal density method, other methods rely on what two effects?
the Josephson effect and the quantum Hall effect
[ "Planck_constant\n\nThe theoretical difficulties arise from the fact that all of the methods except the X-ray crystal density method rely on the theoretical basis of the Josephson effect and the quantum Hall effect. If these theories are slightly inaccurate – though there is no evidence at present to suggest they a...
572971e61d04691400779474
Why does relying on these effects create concern?
If these theories are slightly inaccurate
[ "Planck_constant\n\nThe theoretical difficulties arise from the fact that all of the methods except the X-ray crystal density method rely on the theoretical basis of the Josephson effect and the quantum Hall effect. If these theories are slightly inaccurate – though there is no evidence at present to suggest they a...
572971e61d04691400779475
Using Planck constant values from these effects would lead to what logical issue?
a circular argument
[ "Planck_constant\n\nThe theoretical difficulties arise from the fact that all of the methods except the X-ray crystal density method rely on the theoretical basis of the Josephson effect and the quantum Hall effect. If these theories are slightly inaccurate – though there is no evidence at present to suggest they a...
572971e61d04691400779476
What is the saving grace of relying on these theories?
there are other statistical ways of testing the theories, and the theories have yet to be refuted.
[ "Planck_constant\n\nThe theoretical difficulties arise from the fact that all of the methods except the X-ray crystal density method rely on the theoretical basis of the Josephson effect and the quantum Hall effect. If these theories are slightly inaccurate – though there is no evidence at present to suggest they a...
5729724c1d04691400779485
What is a watt balance?
an instrument for comparing two powers, one of which is measured in SI watts and the other of which is measured in conventional electrical units
[ "Planck_constant\n\nA watt balance is an instrument for comparing two powers, one of which is measured in SI watts and the other of which is measured in conventional electrical units. From the definition of the conventional watt W90, this gives a measure of the product KJ2RK in SI units, where RK is the von Klitzin...
5729724c1d04691400779486
What value does RK represent?
the von Klitzing constant which appears in the quantum Hall effect
[ "Planck_constant\n\nA watt balance is an instrument for comparing two powers, one of which is measured in SI watts and the other of which is measured in conventional electrical units. From the definition of the conventional watt W90, this gives a measure of the product KJ2RK in SI units, where RK is the von Klitzin...
5729724c1d04691400779487
If the effects are valid, for RK = n/e2, what is the measurement of KJ2RK equal to?
the Planck constant
[ "Planck_constant\n\nA watt balance is an instrument for comparing two powers, one of which is measured in SI watts and the other of which is measured in conventional electrical units. From the definition of the conventional watt W90, this gives a measure of the product KJ2RK in SI units, where RK is the von Klitzin...
572973313f37b319004783f3
The gyromagnetic ratio is the constant proportion between the magentic field and what?
the frequency ν of nuclear magnetic resonance
[ "Planck_constant\n\nThe gyromagnetic ratio γ is the constant of proportionality between the frequency ν of nuclear magnetic resonance (or electron paramagnetic resonance for electrons) and the applied magnetic field B: ν = γB. It is difficult to measure gyromagnetic ratios precisely because of the difficulties in p...
572973313f37b319004783f4
How does the water molecule impact the effect of magnetic fields on protons?
The protons are said to be "shielded" from the applied magnetic field by the electrons in the water molecule
[ "Planck_constant\n\nThe gyromagnetic ratio γ is the constant of proportionality between the frequency ν of nuclear magnetic resonance (or electron paramagnetic resonance for electrons) and the applied magnetic field B: ν = γB. It is difficult to measure gyromagnetic ratios precisely because of the difficulties in p...
572973313f37b319004783f5
What three factors impact the gyromagnetic ratio?
related to the shielded proton magnetic moment μ′p, the spin number I (I = 1⁄2 for protons) and the reduced Planck constant.
[ "Planck_constant\n\nThe gyromagnetic ratio γ is the constant of proportionality between the frequency ν of nuclear magnetic resonance (or electron paramagnetic resonance for electrons) and the applied magnetic field B: ν = γB. It is difficult to measure gyromagnetic ratios precisely because of the difficulties in p...
572973313f37b319004783f6
The gyromagnetic ratio is often difficult to determine due to difficulty accurately determining the value of what?
the applied magnetic field B
[ "Planck_constant\n\nThe gyromagnetic ratio γ is the constant of proportionality between the frequency ν of nuclear magnetic resonance (or electron paramagnetic resonance for electrons) and the applied magnetic field B: ν = γB. It is difficult to measure gyromagnetic ratios precisely because of the difficulties in p...
572973b56aef051400154f02
How many methods of measuring the gyromagnetic ratio are there?
there are two methods of measuring the value
[ "Planck_constant\n\nA further complication is that the measurement of γ′p involves the measurement of an electric current: this is invariably measured in conventional amperes rather than in SI amperes, so a conversion factor is required. The symbol Γ′p-90 is used for the measured gyromagnetic ratio using convention...
572973b56aef051400154f03
How do conversion factors compare in "low-field" and "high-field" methods of measuring the gyromagnetic ratio?
the conversion factors are different in the two cases
[ "Planck_constant\n\nA further complication is that the measurement of γ′p involves the measurement of an electric current: this is invariably measured in conventional amperes rather than in SI amperes, so a conversion factor is required. The symbol Γ′p-90 is used for the measured gyromagnetic ratio using convention...
572973b56aef051400154f04
Which method is of interest in determining the Planck constant?
Only the high-field value Γ′p-90(hi) is of interest in determining the Planck constant
[ "Planck_constant\n\nA further complication is that the measurement of γ′p involves the measurement of an electric current: this is invariably measured in conventional amperes rather than in SI amperes, so a conversion factor is required. The symbol Γ′p-90 is used for the measured gyromagnetic ratio using convention...
572973b56aef051400154f05
Why is the measurement of electric current an issue in the estimate of the gyromagnetic ratio?
electric current: this is invariably measured in conventional amperes rather than in SI amperes
[ "Planck_constant\n\nA further complication is that the measurement of γ′p involves the measurement of an electric current: this is invariably measured in conventional amperes rather than in SI amperes, so a conversion factor is required. The symbol Γ′p-90 is used for the measured gyromagnetic ratio using convention...
572974216aef051400154f14
What is the Faraday constant?
the charge of one mole of electrons
[ "Planck_constant\n\nThe Faraday constant F is the charge of one mole of electrons, equal to the Avogadro constant NA multiplied by the elementary charge e. It can be determined by careful electrolysis experiments, measuring the amount of silver dissolved from an electrode in a given time and for a given electric cu...
572974216aef051400154f15
How is the Faraday constant determined?
by careful electrolysis experiments, measuring the amount of silver dissolved from an electrode in a given time and for a given electric current.
[ "Planck_constant\n\nThe Faraday constant F is the charge of one mole of electrons, equal to the Avogadro constant NA multiplied by the elementary charge e. It can be determined by careful electrolysis experiments, measuring the amount of silver dissolved from an electrode in a given time and for a given electric cu...
572974216aef051400154f16
How does the Faraday constant relate to the Planck constant?
Substituting the definitions of NA and e, and converting from conventional electrical units to SI units, gives the relation to the Planck constant.
[ "Planck_constant\n\nThe Faraday constant F is the charge of one mole of electrons, equal to the Avogadro constant NA multiplied by the elementary charge e. It can be determined by careful electrolysis experiments, measuring the amount of silver dissolved from an electrode in a given time and for a given electric cu...
572974216aef051400154f17
How is the Farday constant value quickly calculated?
the Avogadro constant NA multiplied by the elementary charge e
[ "Planck_constant\n\nThe Faraday constant F is the charge of one mole of electrons, equal to the Avogadro constant NA multiplied by the elementary charge e. It can be determined by careful electrolysis experiments, measuring the amount of silver dissolved from an electrode in a given time and for a given electric cu...
572975206aef051400154f2e
What is the primary method for determining the Avogadro constant?
The X-ray crystal density method
[ "Planck_constant\n\nThe X-ray crystal density method is primarily a method for determining the Avogadro constant NA but as the Avogadro constant is related to the Planck constant it also determines a value for h. The principle behind the method is to determine NA as the ratio between the volume of the unit cell of ...
572975206aef051400154f2f
The Avogadro constant is determined to be the ratio between what two factors in the X-ray crystal density method?
the volume of the unit cell of a crystal, measured by X-ray crystallography, and the molar volume of the substance
[ "Planck_constant\n\nThe X-ray crystal density method is primarily a method for determining the Avogadro constant NA but as the Avogadro constant is related to the Planck constant it also determines a value for h. The principle behind the method is to determine NA as the ratio between the volume of the unit cell of ...
572975206aef051400154f30
What element is used typically to establish Avogadro's constant?
Crystals of silicon
[ "Planck_constant\n\nThe X-ray crystal density method is primarily a method for determining the Avogadro constant NA but as the Avogadro constant is related to the Planck constant it also determines a value for h. The principle behind the method is to determine NA as the ratio between the volume of the unit cell of ...
572975206aef051400154f31
How is unit cell volume calculated?
from the spacing between two crystal planes referred to as d220
[ "Planck_constant\n\nThe X-ray crystal density method is primarily a method for determining the Avogadro constant NA but as the Avogadro constant is related to the Planck constant it also determines a value for h. The principle behind the method is to determine NA as the ratio between the volume of the unit cell of ...
572975206aef051400154f32
Calculating molar volume requires knowledge of what two factors?
the density of the crystal and the atomic weight of the silicon used
[ "Planck_constant\n\nThe X-ray crystal density method is primarily a method for determining the Avogadro constant NA but as the Avogadro constant is related to the Planck constant it also determines a value for h. The principle behind the method is to determine NA as the ratio between the volume of the unit cell of ...
57297608af94a219006aa473
What measurement is deemed most important to redefine in terms of physical constants?
the kilogram
[ "Planck_constant\n\nThere are a number of proposals to redefine certain of the SI base units in terms of fundamental physical constants. This has already been done for the metre, which is defined in terms of a fixed value of the speed of light. The most urgent unit on the list for redefinition is the kilogram, whos...
57297608af94a219006aa474
What is the shape of the object that establishes the base unit of the kilogram?
cylinder
[ "Planck_constant\n\nThere are a number of proposals to redefine certain of the SI base units in terms of fundamental physical constants. This has already been done for the metre, which is defined in terms of a fixed value of the speed of light. The most urgent unit on the list for redefinition is the kilogram, whos...
57297608af94a219006aa475
What alloy is the base unit of the kilogram made from?
platinum–iridium
[ "Planck_constant\n\nThere are a number of proposals to redefine certain of the SI base units in terms of fundamental physical constants. This has already been done for the metre, which is defined in terms of a fixed value of the speed of light. The most urgent unit on the list for redefinition is the kilogram, whos...
57297608af94a219006aa476
Where is the base unit for the kilogram kept?
in a vault just outside Paris
[ "Planck_constant\n\nThere are a number of proposals to redefine certain of the SI base units in terms of fundamental physical constants. This has already been done for the metre, which is defined in terms of a fixed value of the speed of light. The most urgent unit on the list for redefinition is the kilogram, whos...
572976ac3f37b31900478449
Where would the decision to change the definition of the kilogram have occured at the earliest?
the General Conference on Weights and Measures in 2011
[ "Planck_constant\n\nThe legal process to change the definition of the kilogram is already underway, but it had been decided that no final decision would be made before the next meeting of the General Conference on Weights and Measures in 2011. (For more detailed information, see kilogram definitions.) The Planck co...
572976ac3f37b3190047844a
Was the Planck constant the only option for redefining the kilogram?
The Planck constant is a leading contender to form the basis of the new definition, although not the only one
[ "Planck_constant\n\nThe legal process to change the definition of the kilogram is already underway, but it had been decided that no final decision would be made before the next meeting of the General Conference on Weights and Measures in 2011. (For more detailed information, see kilogram definitions.) The Planck co...
572976ac3f37b3190047844b
The mass of a resting body with what energy would be equal to a kilogram?
7050135639273999999♠135639274×1042 Hz
[ "Planck_constant\n\nThe legal process to change the definition of the kilogram is already underway, but it had been decided that no final decision would be made before the next meeting of the General Conference on Weights and Measures in 2011. (For more detailed information, see kilogram definitions.) The Planck co...
572976ac3f37b3190047844c
A kilogram could be definined as having a Planck constant of what value?
6966662606895999999♠6.62606896×10−34 J⋅s
[ "Planck_constant\n\nThe legal process to change the definition of the kilogram is already underway, but it had been decided that no final decision would be made before the next meeting of the General Conference on Weights and Measures in 2011. (For more detailed information, see kilogram definitions.) The Planck co...
57293ad06aef051400154ba8
What drives the wider acceptance of renewable energy technologies?
Public policy and political leadership
[ "Renewable_energy_commercialization\n\nPublic policy and political leadership helps to \"level the playing field\" and drive the wider acceptance of renewable energy technologies. Countries such as Germany, Denmark, and Spain have led the way in implementing innovative policies which has driven most of the growth o...
57293ad06aef051400154ba9
Denmark has a committment to 100 percent renewable energy by what year?
2050
[ "Renewable_energy_commercialization\n\nPublic policy and political leadership helps to \"level the playing field\" and drive the wider acceptance of renewable energy technologies. Countries such as Germany, Denmark, and Spain have led the way in implementing innovative policies which has driven most of the growth o...
57293ad06aef051400154baa
How many countries now have renewable energy policies?
144
[ "Renewable_energy_commercialization\n\nPublic policy and political leadership helps to \"level the playing field\" and drive the wider acceptance of renewable energy technologies. Countries such as Germany, Denmark, and Spain have led the way in implementing innovative policies which has driven most of the growth o...
57293b691d0469140077918d
How much was the total investment in renewable energy in 2012?
$244 billion
[ "Renewable_energy_commercialization\n\nTotal investment in renewable energy (including small hydro-electric projects) was $244 billion in 2012, down 12% from 2011 mainly due to dramatically lower solar prices and weakened US and EU markets. As a share of total investment in power plants, wind and solar PV grew from...
57293b691d0469140077918e
Why did the total investment in renewable energy go down in 2012?
dramatically lower solar prices
[ "Renewable_energy_commercialization\n\nTotal investment in renewable energy (including small hydro-electric projects) was $244 billion in 2012, down 12% from 2011 mainly due to dramatically lower solar prices and weakened US and EU markets. As a share of total investment in power plants, wind and solar PV grew from...
57293b691d0469140077918f
What six were the top countries for investment in recent years?
China, Germany, Spain, the United States, Italy, and Brazil
[ "Renewable_energy_commercialization\n\nTotal investment in renewable energy (including small hydro-electric projects) was $244 billion in 2012, down 12% from 2011 mainly due to dramatically lower solar prices and weakened US and EU markets. As a share of total investment in power plants, wind and solar PV grew from...
57293c241d046914007791a9
Who has shown support for ambitious renewable energy goals?
EU member countries
[ "Renewable_energy_commercialization\n\nEU member countries have shown support for ambitious renewable energy goals. In 2010, Eurobarometer polled the twenty-seven EU member states about the target \"to increase the share of renewable energy in the EU by 20 percent by 2020\". Most people in all twenty-seven countrie...
57293c241d046914007791aa
What group polled the 27 EU member states in 2010?
Eurobarometer
[ "Renewable_energy_commercialization\n\nEU member countries have shown support for ambitious renewable energy goals. In 2010, Eurobarometer polled the twenty-seven EU member states about the target \"to increase the share of renewable energy in the EU by 20 percent by 2020\". Most people in all twenty-seven countrie...
57293c241d046914007791ab
The goal was to increase the share of renewable energy in the EU by 20 percent in what year?
2020
[ "Renewable_energy_commercialization\n\nEU member countries have shown support for ambitious renewable energy goals. In 2010, Eurobarometer polled the twenty-seven EU member states about the target \"to increase the share of renewable energy in the EU by 20 percent by 2020\". Most people in all twenty-seven countrie...
57293d583f37b3190047816d
By the end of 2011, total renewable power capacity worldwide exceeded what number?
1,360 GW
[ "Renewable_energy_commercialization\n\nBy the end of 2011, total renewable power capacity worldwide exceeded 1,360 GW, up 8%. Renewables producing electricity accounted for almost half of the 208 GW of capacity added globally during 2011. Wind and solar photovoltaics (PV) accounted for almost 40% and 30% . Based on...
57293d583f37b3190047816e
Renewables contributed what percentage to our energy consumption?
19 percent
[ "Renewable_energy_commercialization\n\nBy the end of 2011, total renewable power capacity worldwide exceeded 1,360 GW, up 8%. Renewables producing electricity accounted for almost half of the 208 GW of capacity added globally during 2011. Wind and solar photovoltaics (PV) accounted for almost 40% and 30% . Based on...
57293d583f37b3190047816f
Renewables contributed what percentage to our electricity generation?
22 percent
[ "Renewable_energy_commercialization\n\nBy the end of 2011, total renewable power capacity worldwide exceeded 1,360 GW, up 8%. Renewables producing electricity accounted for almost half of the 208 GW of capacity added globally during 2011. Wind and solar photovoltaics (PV) accounted for almost 40% and 30% . Based on...
57293ff51d046914007791f3
Who was the UN under-secretary in 2011?
Achim Steiner
[ "Renewable_energy_commercialization\n\nDuring the five-years from the end of 2004 through 2009, worldwide renewable energy capacity grew at rates of 10–60 percent annually for many technologies. In 2011, UN under-secretary general Achim Steiner said: \"The continuing growth in this core segment of the green economy...
57293ff51d046914007791f4
Between what years did worldwide renewable energy capacity grow at rates of 10 to 60 percent annually?
2004 through 2009
[ "Renewable_energy_commercialization\n\nDuring the five-years from the end of 2004 through 2009, worldwide renewable energy capacity grew at rates of 10–60 percent annually for many technologies. In 2011, UN under-secretary general Achim Steiner said: \"The continuing growth in this core segment of the green economy...
57293ff51d046914007791f5
Who is Achim Steiner?
UN under-secretary general
[ "Renewable_energy_commercialization\n\nDuring the five-years from the end of 2004 through 2009, worldwide renewable energy capacity grew at rates of 10–60 percent annually for many technologies. In 2011, UN under-secretary general Achim Steiner said: \"The continuing growth in this core segment of the green economy...
572941266aef051400154c0a
Which group projected that solar plant may produce most of the world's electricity within 50 years?
International Energy Agency
[ "Renewable_energy_commercialization\n\nAccording to a 2011 projection by the International Energy Agency, solar power plants may produce most of the world's electricity within 50 years, significantly reducing the emissions of greenhouse gases that harm the environment. The IEA has said: \"Photovoltaic and solar-the...
572941266aef051400154c0b
Photovoltaic and solar-thermal plants may meet most of the world's demand for electricity by what year?
2060
[ "Renewable_energy_commercialization\n\nAccording to a 2011 projection by the International Energy Agency, solar power plants may produce most of the world's electricity within 50 years, significantly reducing the emissions of greenhouse gases that harm the environment. The IEA has said: \"Photovoltaic and solar-the...
572941266aef051400154c0c
Photovoltaic and solar-thermal plants may meet how much of the world's energy needs by 2060?
half
[ "Renewable_energy_commercialization\n\nAccording to a 2011 projection by the International Energy Agency, solar power plants may produce most of the world's electricity within 50 years, significantly reducing the emissions of greenhouse gases that harm the environment. The IEA has said: \"Photovoltaic and solar-the...
572942721d0469140077920d
Who led the world in renewable energy production in 2013?
China
[ "Renewable_energy_commercialization\n\nIn 2013, China led the world in renewable energy production, with a total capacity of 378 GW, mainly from hydroelectric and wind power. As of 2014, China leads the world in the production and use of wind power, solar photovoltaic power and smart grid technologies, generating a...
572942721d0469140077920e
Since what year has production of solar cells in China expanded 100-fold?
2005
[ "Renewable_energy_commercialization\n\nIn 2013, China led the world in renewable energy production, with a total capacity of 378 GW, mainly from hydroelectric and wind power. As of 2014, China leads the world in the production and use of wind power, solar photovoltaic power and smart grid technologies, generating a...
572942721d0469140077920f
What is the main driver of reduced costs?
market expansion
[ "Renewable_energy_commercialization\n\nIn 2013, China led the world in renewable energy production, with a total capacity of 378 GW, mainly from hydroelectric and wind power. As of 2014, China leads the world in the production and use of wind power, solar photovoltaic power and smart grid technologies, generating a...
572943176aef051400154c1e
What is getting cheaper as a result of technilogical change?
Renewable energy technologies
[ "Renewable_energy_commercialization\n\nRenewable energy technologies are getting cheaper, through technological change and through the benefits of mass production and market competition. A 2011 IEA report said: \"A portfolio of renewable energy technologies is becoming cost-competitive in an increasingly broad rang...
572943176aef051400154c1f
As of what year have there been substantial reductions in the cost of solar and wind technologies?
2011
[ "Renewable_energy_commercialization\n\nRenewable energy technologies are getting cheaper, through technological change and through the benefits of mass production and market competition. A 2011 IEA report said: \"A portfolio of renewable energy technologies is becoming cost-competitive in an increasingly broad rang...
572943176aef051400154c20
What group stated that "cost reductions in critical technologies, such as wind and solar, are set to continue?"
IEA
[ "Renewable_energy_commercialization\n\nRenewable energy technologies are getting cheaper, through technological change and through the benefits of mass production and market competition. A 2011 IEA report said: \"A portfolio of renewable energy technologies is becoming cost-competitive in an increasingly broad rang...
5729442b3f37b319004781db
What is the most economic solution for new grid-connected capacity in areas with good resources?
Renewable energy
[ "Renewable_energy_commercialization\n\nRenewable energy is also the most economic solution for new grid-connected capacity in areas with good resources. As the cost of renewable power falls, the scope of economically viable applications increases. Renewable technologies are now often the most economic solution for ...
5729442b3f37b319004781dc
What happens as the scope of economically viable applications increases?
the cost of renewable power falls
[ "Renewable_energy_commercialization\n\nRenewable energy is also the most economic solution for new grid-connected capacity in areas with good resources. As the cost of renewable power falls, the scope of economically viable applications increases. Renewable technologies are now often the most economic solution for ...
5729442b3f37b319004781dd
What are now often the most economic solution for new generating capacity?
Renewable technologies
[ "Renewable_energy_commercialization\n\nRenewable energy is also the most economic solution for new grid-connected capacity in areas with good resources. As the cost of renewable power falls, the scope of economically viable applications increases. Renewable technologies are now often the most economic solution for ...
572944eb1d04691400779223
What is one problem with biomass?
material directly combusted in cook stoves produces pollutants
[ "Renewable_energy_commercialization\n\nBiomass for heat and power is a fully mature technology which offers a ready disposal mechanism for municipal, agricultural, and industrial organic wastes. However, the industry has remained relatively stagnant over the decade to 2007, even though demand for biomass (mostly wo...
572944eb1d04691400779224
What can be economically competetive but may still require deployment support?
First-generation biomass technologies
[ "Renewable_energy_commercialization\n\nBiomass for heat and power is a fully mature technology which offers a ready disposal mechanism for municipal, agricultural, and industrial organic wastes. However, the industry has remained relatively stagnant over the decade to 2007, even though demand for biomass (mostly wo...
572944eb1d04691400779225
What is a fully maturing technology which offer a ready disposal mechanismm?
Biomass for heat and power
[ "Renewable_energy_commercialization\n\nBiomass for heat and power is a fully mature technology which offers a ready disposal mechanism for municipal, agricultural, and industrial organic wastes. However, the industry has remained relatively stagnant over the decade to 2007, even though demand for biomass (mostly wo...
57294646af94a219006aa23f
What is the term referring to electricity generated by hydropower?
Hydroelectricity
[ "Renewable_energy_commercialization\n\nHydroelectricity is the term referring to electricity generated by hydropower; the production of electrical power through the use of the gravitational force of falling or flowing water. It is the most widely used form of renewable energy, accounting for 16 percent of global el...
57294646af94a219006aa240
What is the most widely used form of renewable energy?
Hydroelectricity
[ "Renewable_energy_commercialization\n\nHydroelectricity is the term referring to electricity generated by hydropower; the production of electrical power through the use of the gravitational force of falling or flowing water. It is the most widely used form of renewable energy, accounting for 16 percent of global el...
57294646af94a219006aa241
Hydroelectricity accounts for what percentage of global electricity generation?
Hydroelectricity
[ "Renewable_energy_commercialization\n\nHydroelectricity is the term referring to electricity generated by hydropower; the production of electrical power through the use of the gravitational force of falling or flowing water. It is the most widely used form of renewable energy, accounting for 16 percent of global el...
57294646af94a219006aa242
Electricity production is expected to increase by what percentage each year for the next 25 years?
3.1%
[ "Renewable_energy_commercialization\n\nHydroelectricity is the term referring to electricity generated by hydropower; the production of electrical power through the use of the gravitational force of falling or flowing water. It is the most widely used form of renewable energy, accounting for 16 percent of global el...
572947721d04691400779241
Hydropower is produced in how many countries?
150
[ "Renewable_energy_commercialization\n\nHydropower is produced in 150 countries, with the Asia-Pacific region generating 32 percent of global hydropower in 2010. China is the largest hydroelectricity producer, with 721 terawatt-hours of production in 2010, representing around 17 percent of domestic electricity use. ...
572947721d04691400779242
Which country is the largest hydroelectricity producer?
China
[ "Renewable_energy_commercialization\n\nHydropower is produced in 150 countries, with the Asia-Pacific region generating 32 percent of global hydropower in 2010. China is the largest hydroelectricity producer, with 721 terawatt-hours of production in 2010, representing around 17 percent of domestic electricity use. ...
572947721d04691400779243
How many hydroelectricity plants are larger than 10 GW?
three
[ "Renewable_energy_commercialization\n\nHydropower is produced in 150 countries, with the Asia-Pacific region generating 32 percent of global hydropower in 2010. China is the largest hydroelectricity producer, with 721 terawatt-hours of production in 2010, representing around 17 percent of domestic electricity use. ...
572947721d04691400779244
What is the average cost of electricity from a hydro plant larger than 10 megawatts?
3 to 5 U.S. cents per kilowatt-hour
[ "Renewable_energy_commercialization\n\nHydropower is produced in 150 countries, with the Asia-Pacific region generating 32 percent of global hydropower in 2010. China is the largest hydroelectricity producer, with 721 terawatt-hours of production in 2010, representing around 17 percent of domestic electricity use. ...
57294c7f3f37b31900478213
What was the geothermal capacity in 1975?
1 GW
[ "Renewable_energy_commercialization\n\nGeothermal power capacity grew from around 1 GW in 1975 to almost 10 GW in 2008. The United States is the world leader in terms of installed capacity, representing 3.1 GW. Other countries with significant installed capacity include the Philippines (1.9 GW), Indonesia (1.2 GW),...
57294c7f3f37b31900478214
What was the geothermal capacity in 2008?
10 GW
[ "Renewable_energy_commercialization\n\nGeothermal power capacity grew from around 1 GW in 1975 to almost 10 GW in 2008. The United States is the world leader in terms of installed capacity, representing 3.1 GW. Other countries with significant installed capacity include the Philippines (1.9 GW), Indonesia (1.2 GW),...
57294c7f3f37b31900478215
In the Phillipines, geothermal represented what percentage of the total power mix at the end of 2008?
17 percent
[ "Renewable_energy_commercialization\n\nGeothermal power capacity grew from around 1 GW in 1975 to almost 10 GW in 2008. The United States is the world leader in terms of installed capacity, representing 3.1 GW. Other countries with significant installed capacity include the Philippines (1.9 GW), Indonesia (1.2 GW),...
57294d2baf94a219006aa271
Where have the majority of photovoltaic power stations been built?
Europe
[ "Renewable_energy_commercialization\n\nMany solar photovoltaic power stations have been built, mainly in Europe. As of July 2012, the largest photovoltaic (PV) power plants in the world are the Agua Caliente Solar Project (USA, 247 MW), Charanka Solar Park (India, 214 MW), Golmud Solar Park (China, 200 MW), Perovo ...
57294d2baf94a219006aa272
Where is the Agua Caliente Solar Project located?
USA
[ "Renewable_energy_commercialization\n\nMany solar photovoltaic power stations have been built, mainly in Europe. As of July 2012, the largest photovoltaic (PV) power plants in the world are the Agua Caliente Solar Project (USA, 247 MW), Charanka Solar Park (India, 214 MW), Golmud Solar Park (China, 200 MW), Perovo ...
57294d2baf94a219006aa273
Where is Charanka Solar Park?
India
[ "Renewable_energy_commercialization\n\nMany solar photovoltaic power stations have been built, mainly in Europe. As of July 2012, the largest photovoltaic (PV) power plants in the world are the Agua Caliente Solar Project (USA, 247 MW), Charanka Solar Park (India, 214 MW), Golmud Solar Park (China, 200 MW), Perovo ...
57294e063f37b3190047821f
Where is Desert Sunlight Solar Farm currently under construction?
Riverside County, California
[ "Renewable_energy_commercialization\n\nThere are also many large plants under construction. The Desert Sunlight Solar Farm under construction in Riverside County, California and Topaz Solar Farm being built in San Luis Obispo County, California are both 550 MW solar parks that will use thin-film solar photovoltaic ...
57294e063f37b31900478220
Where is Desert Sunlight Solar Farm?
San Luis Obispo County, California
[ "Renewable_energy_commercialization\n\nThere are also many large plants under construction. The Desert Sunlight Solar Farm under construction in Riverside County, California and Topaz Solar Farm being built in San Luis Obispo County, California are both 550 MW solar parks that will use thin-film solar photovoltaic ...
57294e063f37b31900478221
Who is building The Califoria Valley Solar Ranch?
SunPower
[ "Renewable_energy_commercialization\n\nThere are also many large plants under construction. The Desert Sunlight Solar Farm under construction in Riverside County, California and Topaz Solar Farm being built in San Luis Obispo County, California are both 550 MW solar parks that will use thin-film solar photovoltaic ...
57294f546aef051400154c9c
Global wind power installations increased by how much in 2010?
35,800 MW
[ "Renewable_energy_commercialization\n\nSome of the second-generation renewables, such as wind power, have high potential and have already realised relatively low production costs. Global wind power installations increased by 35,800 MW in 2010, bringing total installed capacity up to 194,400 MW, a 22.5% increase on ...
57294f546aef051400154c9d
China has how much wind power installed?
42,300 MW
[ "Renewable_energy_commercialization\n\nSome of the second-generation renewables, such as wind power, have high potential and have already realised relatively low production costs. Global wind power installations increased by 35,800 MW in 2010, bringing total installed capacity up to 194,400 MW, a 22.5% increase on ...
57294f546aef051400154c9e
In Denmark, wind power accounts for what percentage of electricity generated?
19%
[ "Renewable_energy_commercialization\n\nSome of the second-generation renewables, such as wind power, have high potential and have already realised relatively low production costs. Global wind power installations increased by 35,800 MW in 2010, bringing total installed capacity up to 194,400 MW, a 22.5% increase on ...
57294f546aef051400154c9f
In Spain, wind power accounts for what percentage of electricity generated?
9%
[ "Renewable_energy_commercialization\n\nSome of the second-generation renewables, such as wind power, have high potential and have already realised relatively low production costs. Global wind power installations increased by 35,800 MW in 2010, bringing total installed capacity up to 194,400 MW, a 22.5% increase on ...