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comparison.
I believe relying on a finite source of energy is short sighted.
Again, Solar Panel production requires the use of energy from Coal in China, so your solution to manufacture more Solar Panels increases the use of Coal.
Yes, Coal is dirty, so quit using Coal to make Solar Panels and Wind Turbines
This we can agree on. Why don't they use renewable energy to make the solar panels.
Yeah, leave it to the Chinese to pour the shit into rivers.
Thank god for regulations here in America
Producing electricity with photovoltaics (PV) emits no pollution, produces no greenhouse gases, and uses no finite fossil fuel resources. The environmental benefits of PV are great. But just as we say that it takes money to make money, it also takes energy to save energy. The term "energy payback" captures this idea. How long does a PV system have to operate to recover the energy--and associated generation of pollution and CO2--that went into making the system, in the first place? Energy payback estimates for rooftop PV systems are 4, 3, 2, and 1 years: 4 years for systems using current multicrystalline-silicon PV modules, 3 years for current thin-film modules, 2 years for anticipated multicrystalline modules, and 1 year for anticipated thin-film modules[.] With energy paybacks of 1 to 4 years and assumed life expectancies of 30 years, 87% to 97% of the energy that PV systems generate won't be plagued by pollution, greenhouse gases, and depletion of resources.
Anyone that dumps raw sewage into rivers should get fined big time.
PV Environmental Research Center, Brookhaven National Laboratory, Upton, New York, Center for Life Cycle Analysis, Columbia University, New York, New York, and Copernicus Institute of Sustainable Development, Utrecht University, Heidelberglaan 2, 3584 CS Utrecht, The Netherlands
Received for review July 17, 2007
Revised manuscript received December 19, 2007
Accepted January 4, 2008
Abstract:
Photovoltaic (PV) technologies have shown remarkable progress recently in terms of annual production capacity and life cycle environmental performances, which necessitate timely updates of environmental indicators. Based on PV production data of 2004–2006, this study presents the life-cycle greenhouse gas emissions, criteria pollutant emissions, and heavy metal emissions from four types of major commercial PV systems: multicrystalline silicon, monocrystalline silicon, ribbon silicon, and thin-film cadmium telluride. Life-cycle emissions were determined by employing average electricity mixtures in Europe and the United States during the materials and module production for each PV system. Among the current vintage of PV technologies, thin-film cadmium telluride (CdTe) PV emits the least amount of harmful air emissions as it requires the least amount of energy during the module production. However, the differences in the emissions between different PV technologies are very small in comparison to the emissions from conventional energy technologies that PV could displace. As a part of prospective analysis, the effect of PV breeder was investigated. Overall, all PV technologies generate far less life-cycle air emissions per GWh than conventional fossil-fuel-based electricity generation technologies. At least 89% of air emissions associated with electricity generation could be prevented if electricity from photovoltaics displaces electricity from the grid.
3 GHG and Criteria Pollutant Emissions
We estimate the emissions GHG, SO2, and NOx during the PV life cycles. Together with the heavy metal emissions assessed later in this paper, these emissions comprise the main hazards to the environment and human health from energy use and materials extraction during the PV life cycle. These emissions are normalized by the electricity generated during the life cycle of PV. The major parameters for the life cycle, i.e., lifetime electricity generation of a PV system, include conversion efficiency (E), solar insolation (I), performance ratio (PR), and lifetime (L). The total lifetime electricity generation (G) per m2 of PV module is calculated as follows: G = E × I × PR × L. We consistently use, for our own analysis, the Southern European average insolation of 1700 kWh/m2/yr, a performance ratio of 0.8, and a lifetime of 30 years.
Alsema and de Wild report that the GHG emissions of Si modules for the year 2004 are within the 30–45 g CO2-equiv/kWh range, with an EPBT of 1.7–2.7 years for a rooftop application under Southern European insolation of 1700 kWh/m2/yr and a performance ratio (PR) of 0.75 (8, 10). Their estimates are based on the electricity mixture for the current geographically specific production of Si (Figure 2, Case 1).
We followed the direct and indirect (due to energy use) emissions of heavy metals (arsenic, cadmium, chromium, lead, mercury, and nickel) during the life cycles of the four PV technologies we studied. The CdTe PV can emit Cd both directly and indirectly whereas the crystalline Si PV stages would emit such only indirectly.
4.1 Direct Cd Emissions
Fthenakis (11) compiled the direct, atmospheric Cd emissions from the life cycle of CdTe PV modules based on 30 years of module lifetime, 9% efficiency, and the average U.S. insolation of 1800 kWh/m2/yr. The total direct emissions of cadmium during the mining, smelting, and purification of the element and the synthesis of CdTe are 0.015 g/GWh. The total direct emissions of cadmium during module manufacturing are 0.004 g/GWh (11). Emissions during accidental releases (e.g., fires) are extremely small, if any. Such emissions could add to the total of 0.02 g/GWh. The latter have been investigated experimentally with the aid of high-energy synchrotron X-ray microprobes (16). Cd emissions from the life cycle of CdTe modules (Table S3 in the Supporting Information) are estimated to be 90–300 times lower than those from coal power plants, which are 2–7 g Cd/GWh (17).
4.2 Indirect Cd Emissions due to Electricity and Fuel Use
We hereby accounted for Cd emissions in the generation of electricity used in producing a PV system. Electricity generation by fossil fuels creates heavy metal emissions as those are contained in coal and oil and a fraction is released in the atmosphere during combustion. The electricity demand for PV modules and BOS were investigated based on the life-cycle inventory of each module and the electricity input data for production of BOS materials. Then, Cd emissions from the electricity demand for each module were assigned, assuming that the life-cycle electricity for the silicon-and CdTe-PV modules are supplied by the UCTE grid.
Indirect Cd emissions include those from using fossil fuel, such as natural gas, heavy oil, and coal for providing heat and mechanical energy during materials processing, for climate control of the manufacturing plant, and for the transportation of materials and products throughout the life cycle of PV modules. The dominant sources of such indirect Cd emissions were found to be the use of coal during steel-making processes and the use of natural gas during glass-making processes. The cadmium emissions from natural gas use are indirect, from the boiler materials and from the electricity supply needed in the boiler, not from the burning of gas itself.
The complete life-cycle atmospheric Cd emissions were estimated by adding the Cd emissions from electricity and fuel demand associated with manufacturing and materials production for PV module and Balance of System (BOS). These are shown in Figure 3. The results show that CdTe PV displacing other electricity technologies actually prevents a significant amount of Cd from being released to the air. Every GWh electricity generated by CdTe PV module can prevent around 4 g of Cd air emissions if used instead of or as a supplement to the UCTE electricity grid. The direct emissions of Cd during the life cycle of CdTe PV are 10 times lower than the indirect emissions due to the electricity and fuel use in the same life cycle, and about 30 times lower than those indirect emissions in the life cycle of crystalline photovoltaics.
An Error Occurred Setting Your User CookieUsing data compiled from the original records of twelve PV manufacturers, we quantified the emissions from the life cycle of four major commercial photovoltaic technologies and showed that they are insignificant in comparison to the emissions that they replace when introduced in average European and U.S. grids. According to our analysis, replacing grid electricity with central PV systems presents significant environmental benefits, which for CdTe PV amounts to 89–98% reductions of GHG emissions, criteria pollutants, heavy metals, and radioactive species. For roof-top dispersed installations, such pollution reductions are expected to be even greater as the loads on the transmission and distribution networks are reduced, and part of the emissions related to the life cycle of these networks are avoided. It is interesting that emissions of heavy metals are greatly reduced even for the types of PV technologies that make direct use of related compounds. For example the emissions of Cd from the life cycle of CdTe PV are 90−300 times lower than those from coal power plants with optimally functioning particulate control devices. In fact, life-cycle Cd emissions are even lower in CdTe PV than in crystalline Si PV, because the former use less energy in their life cycle than the later. In general, thin-film photovoltaics require less energy in their manufacturing than crystalline Si photovoltaics, and this translates to lower emissions of heavy metals, SOx, NOx, PM, and CO2. In any case, emissions from any type of PV system are expected to be lower than those from conventional energy systems because PV does not require fuel to operate. PV technologies provide the benefits of significantly curbing air emissions harmful to human and ecological health. It is noted that the environmental profiles of photovoltaics are further improving as efficiencies and material utilization rates increase and this kind of analysis needs to be updated periodically. Also, future very large penetrations of PV would alter the grid composition and this has to be accounted for in future analyses.
MYTH: Solar Energy Is "Dirty"
◾Claiming that a "green future" would be "dirty," the Taxpayer Protection Alliance's Drew Johnson wrote in a Washington Examiner op-ed that "It turns out that it takes a lot of power (and a lot of carbon) to build solar panels and wind turbines." [Washington Examiner, 7/24/12]
◾A Wall Street Journal editorial lent some credence to the claim that solar "really doesn't reduce greenhouse gas emissions" because the carbon savings from solar projects on desert land could be "negat[ed]" by disturbing caliche deposits that release carbon dioxide. [Wall Street Journal, 9/4/12]
◾At the American Enterprise Institute's blog, Kenneth Green promoted a press release claiming that "Solar cells do not offset greenhouse gases" because solar cell production emits gases that "make carbon dioxide (CO2) seem harmless." [American Enterprise Institute, 1/23/13]
FACT: Solar Energy Can Greatly Reduce Pollution
Solar Energy Emits Much Fewer Greenhouse Gas Emissions Than Fossil Fuels. A special report by the International Panel on Climate Change's Working Group III examined hundreds of estimates of greenhouse gas emissions (including the potent but rare gases that AEI referred to), and compiled the results of the most thorough studies. This chart of their results shows that renewable and nuclear energy have a substantially lower impact than fossil fuels over the lifespan of each power source:
Producing electricity with photovoltaics (PV) emits no pollution, produces no greenhouse gases, and uses no finite fossil fuel resources. The environmental benefits of PV are great. But just as we say that it takes money to make money, it also takes energy to save energy. The term "energy payback" captures this idea. How long does a PV system have to operate to recover the energy--and associated generation of pollution and CO2--that went into making the system, in the first place? Energy payback estimates for rooftop PV systems are 4, 3, 2, and 1 years: 4 years for systems using current multicrystalline-silicon PV modules, 3 years for current thin-film modules, 2 years for anticipated multicrystalline modules, and 1 year for anticipated thin-film modules[.] With energy paybacks of 1 to 4 years and assumed life expectancies of 30 years, 87% to 97% of the energy that PV systems generate won't be plagued by pollution, greenhouse gases, and depletion of resources.
NREL: 87 To 97 Percent Of Solar PV Power Will Create No Pollution. A report by the Department of Energy's National Renewable Energy Laboratory explained that producing electricity with a solar photovoltaic (PV) system produces no greenhouse gases, greatly offsetting emissions from construction:
This answers some of the questions. For the rest I just have to thank god for our regulations
Emissions from Photovoltaic Life Cycles
Vasilis M. Fthenakis,* Hyung Chul Kim, and Erik Alsema§
PV Environmental Research Center, Brookhaven National Laboratory, Upton, New York, Center for Life Cycle Analysis, Columbia University, New York, New York, and Copernicus Institute of Sustainable Development, Utrecht University, Heidelberglaan 2, 3584 CS Utrecht, The Netherlands
Received for review July 17, 2007
Revised manuscript received December 19, 2007
Accepted January 4, 2008
Abstract:
Photovoltaic (PV) technologies have shown remarkable progress recently in terms of annual production capacity and life cycle environmental performances, which necessitate timely updates of environmental indicators. Based on PV production data of 20042006, this study presents the life-cycle greenhouse gas emissions, criteria pollutant emissions, and heavy metal emissions from four types of major commercial PV systems: multicrystalline silicon, monocrystalline silicon, ribbon silicon, and thin-film cadmium telluride. Life-cycle emissions were determined by employing average electricity mixtures in Europe and the United States during the materials and module production for each PV system. Among the current vintage of PV technologies, thin-film cadmium telluride (CdTe) PV emits the least amount of harmful air emissions as it requires the least amount of energy during the module production. However, the differences in the emissions between different PV technologies are very small in comparison to the emissions from conventional energy technologies that PV could displace. As a part of prospective analysis, the effect of PV breeder was investigated. Overall, all PV technologies generate far less life-cycle air emissions per GWh than conventional fossil-fuel-based electricity generation technologies. At least 89% of air emissions associated with electricity generation could be prevented if electricity from photovoltaics displaces electricity from the grid.
3 GHG and Criteria Pollutant Emissions
We estimate the emissions GHG, SO2, and NOx during the PV life cycles. Together with the heavy metal emissions assessed later in this paper, these emissions comprise the main hazards to the environment and human health from energy use and materials extraction during the PV life cycle. These emissions are normalized by the electricity generated during the life cycle of PV. The major parameters for the life cycle, i.e., lifetime electricity generation of a PV system, include conversion efficiency (E), solar insolation (I), performance ratio (PR), and lifetime (L). The total lifetime electricity generation (G) per m2 of PV module is calculated as follows: G = E × I × PR × L. We consistently use, for our own analysis, the Southern European average insolation of 1700 kWh/m2/yr, a performance ratio of 0.8, and a lifetime of 30 years.
Alsema and de Wild report that the GHG emissions of Si modules for the year 2004 are within the 3045 g CO2-equiv/kWh range, with an EPBT of 1.72.7 years for a rooftop application under Southern European insolation of 1700 kWh/m2/yr and a performance ratio (PR) of 0.75 (8, 10). Their estimates are based on the electricity mixture for the current geographically specific production of Si (Figure 2, Case 1).
4 Heavy Metal Emissions
We followed the direct and indirect (due to energy use) emissions of heavy metals (arsenic, cadmium, chromium, lead, mercury, and nickel) during the life cycles of the four PV technologies we studied. The CdTe PV can emit Cd both directly and indirectly whereas the crystalline Si PV stages would emit such only indirectly.
4.1 Direct Cd Emissions
Fthenakis (11) compiled the direct, atmospheric Cd emissions from the life cycle of CdTe PV modules based on 30 years of module lifetime, 9% efficiency, and the average U.S. insolation of 1800 kWh/m2/yr. The total direct emissions of cadmium during the mining, smelting, and purification of the element and the synthesis of CdTe are 0.015 g/GWh. The total direct emissions of cadmium during module manufacturing are 0.004 g/GWh (11). Emissions during accidental releases (e.g., fires) are extremely small, if any. Such emissions could add to the total of 0.02 g/GWh. The latter have been investigated experimentally with the aid of high-energy synchrotron X-ray microprobes (16). Cd emissions from the life cycle of CdTe modules (Table S3 in the Supporting Information) are estimated to be 90300 times lower than those from coal power plants, which are 27 g Cd/GWh (17).
4.2 Indirect Cd Emissions due to Electricity and Fuel Use
We hereby accounted for Cd emissions in the generation of electricity used in producing a PV system. Electricity generation by fossil fuels creates heavy metal emissions as those are contained in coal and oil and a fraction is released in the atmosphere during combustion. The electricity demand for PV modules and BOS were investigated based on the life-cycle inventory of each module and the electricity input data for production of BOS materials. Then, Cd emissions from the electricity demand for each module were assigned, assuming that the life-cycle electricity for the silicon-and CdTe-PV modules are supplied by the UCTE grid.
Indirect Cd emissions include those from using fossil fuel, such as natural gas, heavy oil, and coal for providing heat and mechanical energy during materials processing, for climate control of the manufacturing plant, and for the transportation of materials and products throughout the life cycle of PV modules. The dominant sources of such indirect Cd emissions were found to be the use of coal during steel-making processes and the use of natural gas during glass-making processes. The cadmium emissions from natural gas use are indirect, from the boiler materials and from the electricity supply needed in the boiler, not from the burning of gas itself.
The complete life-cycle atmospheric Cd emissions were estimated by adding the Cd emissions from electricity and fuel demand associated with manufacturing and materials production for PV module and Balance of System (BOS). These are shown in Figure 3. The results show that CdTe PV displacing other electricity technologies actually prevents a significant amount of Cd from being released to the air. Every GWh electricity generated by CdTe PV module can prevent around 4 g of Cd air emissions if used instead of or as a supplement to the UCTE electricity grid. The direct emissions of Cd during the life cycle of CdTe PV are 10 times lower than the indirect emissions due to the electricity and fuel use in the same life cycle, and about 30 times lower than those indirect emissions in the life cycle of crystalline photovoltaics.
6 Discussion
An Error Occurred Setting Your User CookieUsing data compiled from the original records of twelve PV manufacturers, we quantified the emissions from the life cycle of four major commercial photovoltaic technologies and showed that they are insignificant in comparison to the emissions that they replace when introduced in average European and U.S. grids. According to our analysis, replacing grid electricity with central PV systems presents significant environmental benefits, which for CdTe PV amounts to 8998% reductions of GHG emissions, criteria pollutants, heavy metals, and radioactive species. For roof-top dispersed installations, such pollution reductions are expected to be even greater as the loads on the transmission and distribution networks are reduced, and part of the emissions related to the life cycle of these networks are avoided. It is interesting that emissions of heavy metals are greatly reduced even for the types of PV technologies that make direct use of related compounds. For example the emissions of Cd from the life cycle of CdTe PV are 90−300 times lower than those from coal power plants with optimally functioning particulate control devices. In fact, life-cycle Cd emissions are even lower in CdTe PV than in crystalline Si PV, because the former use less energy in their life cycle than the later. In general, thin-film photovoltaics require less energy in their manufacturing than crystalline Si photovoltaics, and this translates to lower emissions of heavy metals, SOx, NOx, PM, and CO2. In any case, emissions from any type of PV system are expected to be lower than those from conventional energy systems because PV does not require fuel to operate. PV technologies provide the benefits of significantly curbing air emissions harmful to human and ecological health. It is noted that the environmental profiles of photovoltaics are further improving as efficiencies and material utilization rates increase and this kind of analysis needs to be updated periodically. Also, future very large penetrations of PV would alter the grid composition and this has to be accounted for in future analyses.
Yeah, leave it to the Chinese to pour the shit into rivers.
Thank god for regulations here in America
Concerns have been expressed recently about pollution from solar panels both during the manufacturing process and when they reach the end of their usable lives.
The manufacture of panels frequently involves toxic heavy metals such as cadmium, lead and mercury as well as producing CO2. However, a recent study found that due to the heavy metal content of fossil fuels, if we were to switch entirely from fossil to solar, overall there would still be a 90% reduction of pollution released into the atmosphere. A recently developed panel, based on cadmium telluride, produces 300x less emissions in its manufacture when directly compared to coal power plants according to Vasilis Fthenakis, from Brookhaven National Laboratory, USA.
Another issue discussed in solar panel manufacture is by-products such as hydrochloric acid. In factories in Europe and America all by-products are recycled. In countries such as China, where there are not so many rules, problems have been reported with toxic waste. These troubles are a symptom of economic corner-cutting and by no means isolated to the solar industry. A simple remedy to ensure solar panel manufacture with minimal pollution, is for companies to only accept sources of materials where there are stringent standards in place, thus placing economic pressure on factories to develop effective waste management.
A further concern is the safe disposal of panels containing toxic material at the end of their useful lives. However, the risk of pollution is far lower than that caused by household electrical goods due to the fact that solar panels are removed by trained professionals. A solar panel is effective for over 20 years, so adequate recycling facilities can be developed to meet the increasing demand. With disposal now more important, recycling technology can now be developed alongside solar technology so that sustainability can be guaranteed from the outset.
Yeah, leave it to the Chinese to pour the shit into rivers.
Thank god for regulations here in America
To a point, yes indeed..but overkill has moved manufacturing overseas.
Beijing..a beautiful place
Beijing announces emergency measures amid fog of pollution - CNN.com
Emissions from Photovoltaic Life Cycles
Vasilis M. Fthenakis,* Hyung Chul Kim, and Erik Alsema§
PV Environmental Research Center, Brookhaven National Laboratory, Upton, New York, Center for Life Cycle Analysis, Columbia University, New York, New York, and Copernicus Institute of Sustainable Development, Utrecht University, Heidelberglaan 2, 3584 CS Utrecht, The Netherlands
Received for review July 17, 2007
Revised manuscript received December 19, 2007
Accepted January 4, 2008
Abstract:
Photovoltaic (PV) technologies have shown remarkable progress recently in terms of annual production capacity and life cycle environmental performances, which necessitate timely updates of environmental indicators. Based on PV production data of 20042006, this study presents the life-cycle greenhouse gas emissions, criteria pollutant emissions, and heavy metal emissions from four types of major commercial PV systems: multicrystalline silicon, monocrystalline silicon, ribbon silicon, and thin-film cadmium telluride. Life-cycle emissions were determined by employing average electricity mixtures in Europe and the United States during the materials and module production for each PV system. Among the current vintage of PV technologies, thin-film cadmium telluride (CdTe) PV emits the least amount of harmful air emissions as it requires the least amount of energy during the module production. However, the differences in the emissions between different PV technologies are very small in comparison to the emissions from conventional energy technologies that PV could displace. As a part of prospective analysis, the effect of PV breeder was investigated. Overall, all PV technologies generate far less life-cycle air emissions per GWh than conventional fossil-fuel-based electricity generation technologies. At least 89% of air emissions associated with electricity generation could be prevented if electricity from photovoltaics displaces electricity from the grid.
3 GHG and Criteria Pollutant Emissions
We estimate the emissions GHG, SO2, and NOx during the PV life cycles. Together with the heavy metal emissions assessed later in this paper, these emissions comprise the main hazards to the environment and human health from energy use and materials extraction during the PV life cycle. These emissions are normalized by the electricity generated during the life cycle of PV. The major parameters for the life cycle, i.e., lifetime electricity generation of a PV system, include conversion efficiency (E), solar insolation (I), performance ratio (PR), and lifetime (L). The total lifetime electricity generation (G) per m2 of PV module is calculated as follows: G = E × I × PR × L. We consistently use, for our own analysis, the Southern European average insolation of 1700 kWh/m2/yr, a performance ratio of 0.8, and a lifetime of 30 years.
Alsema and de Wild report that the GHG emissions of Si modules for the year 2004 are within the 3045 g CO2-equiv/kWh range, with an EPBT of 1.72.7 years for a rooftop application under Southern European insolation of 1700 kWh/m2/yr and a performance ratio (PR) of 0.75 (8, 10). Their estimates are based on the electricity mixture for the current geographically specific production of Si (Figure 2, Case 1).
4 Heavy Metal Emissions
We followed the direct and indirect (due to energy use) emissions of heavy metals (arsenic, cadmium, chromium, lead, mercury, and nickel) during the life cycles of the four PV technologies we studied. The CdTe PV can emit Cd both directly and indirectly whereas the crystalline Si PV stages would emit such only indirectly.
4.1 Direct Cd Emissions
Fthenakis (11) compiled the direct, atmospheric Cd emissions from the life cycle of CdTe PV modules based on 30 years of module lifetime, 9% efficiency, and the average U.S. insolation of 1800 kWh/m2/yr. The total direct emissions of cadmium during the mining, smelting, and purification of the element and the synthesis of CdTe are 0.015 g/GWh. The total direct emissions of cadmium during module manufacturing are 0.004 g/GWh (11). Emissions during accidental releases (e.g., fires) are extremely small, if any. Such emissions could add to the total of 0.02 g/GWh. The latter have been investigated experimentally with the aid of high-energy synchrotron X-ray microprobes (16). Cd emissions from the life cycle of CdTe modules (Table S3 in the Supporting Information) are estimated to be 90300 times lower than those from coal power plants, which are 27 g Cd/GWh (17).
4.2 Indirect Cd Emissions due to Electricity and Fuel Use
We hereby accounted for Cd emissions in the generation of electricity used in producing a PV system. Electricity generation by fossil fuels creates heavy metal emissions as those are contained in coal and oil and a fraction is released in the atmosphere during combustion. The electricity demand for PV modules and BOS were investigated based on the life-cycle inventory of each module and the electricity input data for production of BOS materials. Then, Cd emissions from the electricity demand for each module were assigned, assuming that the life-cycle electricity for the silicon-and CdTe-PV modules are supplied by the UCTE grid.
Indirect Cd emissions include those from using fossil fuel, such as natural gas, heavy oil, and coal for providing heat and mechanical energy during materials processing, for climate control of the manufacturing plant, and for the transportation of materials and products throughout the life cycle of PV modules. The dominant sources of such indirect Cd emissions were found to be the use of coal during steel-making processes and the use of natural gas during glass-making processes. The cadmium emissions from natural gas use are indirect, from the boiler materials and from the electricity supply needed in the boiler, not from the burning of gas itself.
The complete life-cycle atmospheric Cd emissions were estimated by adding the Cd emissions from electricity and fuel demand associated with manufacturing and materials production for PV module and Balance of System (BOS). These are shown in Figure 3. The results show that CdTe PV displacing other electricity technologies actually prevents a significant amount of Cd from being released to the air. Every GWh electricity generated by CdTe PV module can prevent around 4 g of Cd air emissions if used instead of or as a supplement to the UCTE electricity grid. The direct emissions of Cd during the life cycle of CdTe PV are 10 times lower than the indirect emissions due to the electricity and fuel use in the same life cycle, and about 30 times lower than those indirect emissions in the life cycle of crystalline photovoltaics.
6 Discussion
An Error Occurred Setting Your User CookieUsing data compiled from the original records of twelve PV manufacturers, we quantified the emissions from the life cycle of four major commercial photovoltaic technologies and showed that they are insignificant in comparison to the emissions that they replace when introduced in average European and U.S. grids. According to our analysis, replacing grid electricity with central PV systems presents significant environmental benefits, which for CdTe PV amounts to 8998% reductions of GHG emissions, criteria pollutants, heavy metals, and radioactive species. For roof-top dispersed installations, such pollution reductions are expected to be even greater as the loads on the transmission and distribution networks are reduced, and part of the emissions related to the life cycle of these networks are avoided. It is interesting that emissions of heavy metals are greatly reduced even for the types of PV technologies that make direct use of related compounds. For example the emissions of Cd from the life cycle of CdTe PV are 90−300 times lower than those from coal power plants with optimally functioning particulate control devices. In fact, life-cycle Cd emissions are even lower in CdTe PV than in crystalline Si PV, because the former use less energy in their life cycle than the later. In general, thin-film photovoltaics require less energy in their manufacturing than crystalline Si photovoltaics, and this translates to lower emissions of heavy metals, SOx, NOx, PM, and CO2. In any case, emissions from any type of PV system are expected to be lower than those from conventional energy systems because PV does not require fuel to operate. PV technologies provide the benefits of significantly curbing air emissions harmful to human and ecological health. It is noted that the environmental profiles of photovoltaics are further improving as efficiencies and material utilization rates increase and this kind of analysis needs to be updated periodically. Also, future very large penetrations of PV would alter the grid composition and this has to be accounted for in future analyses.
You say that without a clue of what you're talking with. People make a profit off of solar all the time.
Renewables you support-solar or wind. I support both
Feb. 26, 2008 In a finding that could help ease concerns about the potential environmental impact of manufacturing solar cells, scientists report that the manufacture of solar cells produces far fewer air pollutants than conventional fossil fuel technologies. Their report is the first comprehensive study on the pollutants produced during the manufacture of solar cells.
