Policy Implications of Greenhouse Warming Mitigation, Adaptation, and the Science Base (1992) / Chapter Skim
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25 Nonenergy Emission Reduction
25 Nonenergy Emission Reduction
Pages 376-413
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From page 376... ...
Emissions of CFCs are scheduled to be eliminated under the Montreal Protocol, an international treaty signed in 1987 and strengthened in 1990, that commits nations to act to preserve the ozone layer. Positive action under the Protocol including bringing additional nations under its umbrella continues to be a visible demonstration of the possibility of global action on environmental questions.
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From page 377... ...
Besides having a role in ozone depletion, CFCS are also greenhouse gases. Unlike the other greenhouse gases, which began to increase during the Industrial Revolution (1850)
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From page 378... ...
, which can be found in everything from mobile air conditioners to fire extinguishers to plastic foams in residential, commercial, and industrial applications. Over the last decade, the fractional contribution of CFCs to greenhouse warming has been about 20 percent.
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From page 379... ...
30 million freezers 180,000 refrigerated trucks 27,000 refrigerated rail cars 250,000 restaurants 40,000 supermarkets 160,000 other food stores Mobile air CFC-12 (120.0) 90 million cars and light conditioning duty trucks Plastic foams CFC- 11 ~ 150.7)
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From page 380... ...
As a group, the HCFCs and HFCs under evaluation have about onetenth the global warming potential of CFCs, and less than one-twentieth the ozone depletion potential of CFCs, because the hydrogen in these two alternatives destabilizes these chemicals and lowers their residence time in the atmosphere and thus their potential to contribute to greenhouse warming and ozone depletion. Furthermore, because HFCs contain no chlorine, they cannot contribute to ozone depletion (see Table 25.2~.
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These global warming potentials are estimates of the total cumulative (over time) calculated warming due to emission of 1 kg of a compound relative to the total cumulative calculated warming due to emission of 1 kg CO2.
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This method of calculating global warming potentials differs slightly from that used by the Intergovernmental Panel on Climate Change (1990~. They computed relative effects over the first 2O, 100, and 500 years after instantaneous injections of 1 kg of each of the compounds into the atmosphere to derive the values in Table 2.8 of IPCC (Intergovernmental Panel on Climate Change, 19901.
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From page 383... ...
A comparison of the curve for continued use of CFCs with the lower curve demonstrates the effects of the decreased demand for fluorocarbons due to conservation and replacement by nonfluorocarbon alternatives, and also the lower global warming potentials of the HCFCs and HFCs targeted to replace CFCs. Global compliance with a CFC phaseout by 2000 (2010 in developing countries)
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From page 384... ...
Because these substitutes are less energy efficient, the net contribution to global warming may be adverse, a possibility that should be taken into account. Appliance manufacturers put insulating foam in refrigerators to increase their energy efficiency as required by statute.
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From page 385... ...
Serious efforts at refrigerant recovery and recycling in the mobile air conditioning industry can further reduce this greenhouse contribution to less than 5 percent of its present level. No nonfluorocarbon alternative air conditioning technology is currently suitable for this mobile market.
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From page 386... ...
and methyl chloroform (CH3CCl3, emissions are controlled in the amended Montreal Protocol because of their potential contributions to ozone depletion. The use of CC14 will be eliminated by 2000, and the use of CH3CCl3 by 2005.
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From page 387... ...
In those cases, the energy saved, and hence the CO2 emissions prevented, may reduce the contribution to global warming by an amount that is greater than the direct contribution from emission of the fluorocarbon. Chlorofluorocarbons will be replaced in most countries because of concerns over their potential contribution to ozone depletion.
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3g8 At a' 4= ct v: a' ~ ~ it o ·> V 5 V O O cat ~0 0 0 cat Cal a_ U)
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FIGURE 25.6 Cost and greenhouse warming benefit of CFC phaseout policy options in the United States. into account all safety and environmental concerns.
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Policy Options Within the United States, there have been embryonic discussions regarding a proposal for a global emissions tax, based on global warming potentials, to reduce carbon emissions. Currently, there is an excise tax on the Montreal Protocol CFCs, based on ozone depletion potential, applied at the production stage.
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The subject of financial aid is still being addressed on a world scale. The Economic Panel Report on the Montreal Protocol and Substances That Deplete the Ozone Layer (United Nations Environment Programme, 1989)
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From page 392... ...
Unless the energy efficiency of the third-generation technology is at least as great as that of the HCFC technology it would replace, the added contribution from increased CO2 emissions due to increased energy consumption could offset the decreases due to elimination of HCFCs. Finding and implementing suitable third-generation technology could prove to be a significant challenge, and it is currently unclear what that technology might be.
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From page 393... ...
to HCFCs and HFCs, which have lower global warming effects because of their shorter atmospheric lifetimes. The Montreal Protocol provides a mechanism to monitor and manage this result to ensure protection of the stratospheric ozone shield.
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The analysis in this chapter reviews both the potential of reducing emissions during production and the desire of the consumer for agricultural goods that generate greenhouse gas emissions. Methane The primary agricultural sources of CH4 In the United States are paddy rice and ruminants.
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The biological efficiency of both rice and ruminant animals can be improved. For example, the biological efficiency of paddy rice has improved in recent decades.
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396 au Ct ._ ._ ~: o v s~ 3 C~ ._ 50 ¢ ._ V CQ C~ V _, V U: V V)
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From page 398... ...
Improved residue straw management in rice paddies offers some scope for ClI4 reduction, but this is limited because rice straw provides nutrients to soils that would otherwise come from fertilizer, which itself entails N2O emissions. Agricultural practices can also be changed so that greenhouse gas emissions are reduced.
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From page 399... ...
Policy Options Consumption and production of paddy rice and ruminant products could be reduced by increasing the price of these goods. When prices to consumers increase, it is well established that consumption shifts to substitute products.
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. For countries that are exporters of rice and ruminant products, the policy options are different.
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More information on the way in which these estimates were calculated is given in Appendix L Price policy reforms would probably have no real effect on greenhouse gas emissions except in U.S.
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Although the accuracy of these values is questionable due to lack of worldwide information on biogenic sources, they do indicate the importance of the contribution to N2O emissions from fertilizer application in relation to that from fossil fuels. The IPCC estimates that N2O was responsible for approximately 5 percent of the greenhouse gas contribution during the 1980s (see Chapter 19 for more details; Intergovernmental Panel on Climate Change, 19901.
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Policy Options Nitrogen fertilizer use is widespread, being heaviest in Europe. Some crops in some countries use little fertilizer (cassava and legumes)
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It should be recognized, however, that the substitute crops for upland rice are other upland crops, not paddy rice. More upland rice production will increase rice supplies and lower rice prices generally, however, thus having a small discouragement effect on paddy rice product~on.
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From page 405... ...
As a rough approximation, most studies assume that landfill gas is 50 percent CH4 and 50 percent CO2 by volume, with trace amounts of other constituents. The time required for significant production of CH4 can vary from 10 to 100 years or more, depending on the landfill properties noted above.
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From page 406... ...
does not include a time lag between waste generation and landfill gas emissions. In the United States, more detailed estimates of CH4 generation rates have recently been developed by EPA as part of a proposal for controlling air emissions from municipal solid waste (MSW)
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From page 407... ...
Adjusting for the differences in molecular weight, CO2 mass emissions thus are approximately 2.75 times greater than the CH4 values in Table 25.7. Emission Control Methods Reduction of CH4 from active or inactive landfills requires that the gas first be collected and then utilized in an energy recovery system or simply burned (flared)
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From page 408... ...
In the United States, approximately 17 percent of the operating municipal landfills employ some form of CH4 recovery and mitigation system, although less than 2 percent of the sites recover CH4 for energy use (Lashof and Tirpak, 1990~. Recently, however, EPA announced its intent to require the collection and control of landfill gases under Section 111 of the Clean Air Act (which pertains to new sources)
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From page 409... ...
The average CH4 emission reduction encompassed by the three regulatory alternatives ranges from 39 to 82 percent at costs of $9 to $29/t CHA removed. The current EPA draft proposal calls for implementing "regulatory TABLE 25.8 Landfill CH4 Reduction Control Costs New Landfills Existing Landfills Regulatory CH4 Reduction Costa CH4 Reduction Costa Alternative (%)
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From page 410... ...
Another significant impediment to energy recovery is that some existing state regulations establish unlimited liability for any potential contamination problems at landfill resource recovery projects (Lashof and Tirpak, 1990~. Policy Options As discussed above, EPA already plans to require collection and combustion of landfill gas from large facilities.
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From page 411... ...
lists four major health and welfare effects that motivate the regulation of landfill gas emissions: (1) human health and vegetation effects caused by tropospheric ozone, which is formed from non-CH4 organic compound emissions; (2)
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From page 412... ...
1991. Doing well by doing good: Technology transfer to protect the ozone layer.
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From page 413... ...
1989. Economic Panel Report: Montreal Protocol and Substances That Deplete the Ozone Layer.
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