HARDBACK
\$99.95

Page 808

### Appendix M Landfill Methane Reduction

As shown in Chapter 25, the potential emission reductions for CH4 from landfills are given in column 1 of Table 25.8.1 Under regulatory alternative 2, emissions from existing landfills can be reduced by 60 percent, and new landfills by 65 percent. Multiplying these percentages times the CH4 emissions in Table 25.7 as shown below yields 11.1 Mt of CH4 emission reduction per year.

 Existing 18 × 0.60 = 10.8 New 0.53 × 0.65 = 0.34 TOTAL CH4 = 11.1 Mt/yr

Next, this number must be converted to CO2 equivalence. Information from the IPCC shows that each kilogram of CH4 is equivalent to 21 times the global warming potential of CO2 for a 100-yr time horizon. Therefore

11.1 Mt CH4/yr × 21 CO2 eq./CH4 = 233 Mt CO2 eq./yr

and

(\$22.5/t CH4)(1 CH4/21 CO2) = \$1.07/t CO2 eq.

Although these estimates are for 1997, it is assumed that they would be roughly the same for 1990.

#### Note

1. Tons (t) are metric; 1 Mt = 1 megaton = 1 million tons.

The National Academies of Sciences, Engineering, and Medicine
500 Fifth St. N.W. | Washington, D.C. 20001