Drawdown has a website with a ranked list now
https://www.drawdown.org/solutions-summary-by-rankRank Solution Sector TOTAL ATMOSPHERIC CO2-EQ REDUCTION (GT) Net Cost (BILLIONS US $) Savings (BILLIONS US $)
1 Refrigerant Management Materials 89.74 N/A $-902.77
2 Wind Turbines (Onshore) Electricity Generation 84.60 $1,225.37 $7,425.00
3 Reduced Food Waste Food 70.53 N/A N/A
4 Plant-Rich Diet Food 66.11 N/A N/A
5 Tropical Forests Land Use 61.23 N/A N/A
6 Educating Girls Women and Girls 59.60 N/A N/A
7 Family Planning Women and Girls 59.60 N/A N/A
8 Solar Farms Electricity Generation 36.90 $-80.60 $5,023.84
9 Silvopasture Food 31.19 $41.59 $699.37
10 Rooftop Solar Electricity Generation 24.60 $453.14 $3,457.63
11 Regenerative Agriculture Food 23.15 $57.22 $1,928.10
12 Temperate Forests Land Use 22.61 N/A N/A
13 Peatlands Land Use 21.57 N/A N/A
14 Tropical Staple Trees Food 20.19 $120.07 $626.97
15 Afforestation Land Use 18.06 $29.44 $392.33
16 Conservation Agriculture Food 17.35 $37.53 $2,119.07
17 Tree Intercropping Food 17.20 $146.99 $22.10
18 Geothermal Electricity Generation 16.60 $-155.48 $1,024.34
19 Managed Grazing Food 16.34 $50.48 $735.27
20 Nuclear Electricity Generation 16.09 $0.88 $1,713.40
21 Clean Cookstoves Food 15.81 $72.16 $166.28
22 Wind Turbines (Offshore) Electricity Generation 14.10 $545.30 $762.50
23 Farmland Restoration Food 14.08 $72.24 $1,342.47
24 Improved Rice Cultivation Food 11.34 N/A $519.06
25 Concentrated Solar Electricity Generation 10.90 $1,319.70 $413.85
26 Electric Vehicles Transport 10.80 $14,148.00 $9,726.40
27 District Heating Buildings and Cities 9.38 $457.10 $3,543.50
28 Multistrata Agroforestry Food 9.28 $26.76 $709.75
29 Wave and Tidal Electricity Generation 9.20 $411.84 $-1,004.70
30 Methane Digesters (Large) Electricity Generation 8.40 $201.41 $148.83
31 Insulation Buildings and Cities 8.27 $3,655.92 $2,513.33
32 Ships Transport 7.87 $915.93 $424.38
33 LED Lighting (Household) Buildings and Cities 7.81 $323.52 $1,729.54
34 Biomass Electricity Generation 7.50 $402.31 $519.35
35 Bamboo Land Use 7.22 $23.79 $264.80
36 Alternative Cement Materials 6.69 $-273.90 N/A
37 Mass Transit Transport 6.57 N/A $2,379.73
38 Forest Protection Land Use 6.20 N/A N/A
39 Indigenous Peoples’ Land Management Land Use 6.19 N/A N/A
40 Trucks Transport 6.18 $543.54 $2,781.63
41 Solar Water Electricity Generation 6.08 $2.99 $773.65
42 Heat Pumps Buildings and Cities 5.20 $118.71 $1,546.66
43 Airplanes Transport 5.05 $662.42 $3,187.80
44 LED Lighting (Commercial) Buildings and Cities 5.04 $-205.05 $1,089.63
45 Building Automation Buildings and Cities 4.62 $68.12 $880.55
46 Water Saving - Home Materials 4.61 $72.44 $1,800.12
47 Bioplastic Materials 4.30 $19.15 N/A
48 In-Stream Hydro Electricity Generation 4.00 $202.53 $568.36
49 Cars Transport 4.00 $-598.69 $1,761.72
50 Cogeneration Electricity Generation 3.97 $279.25 $566.93
51 Perennial Biomass Land Use 3.33 $77.94 $541.89
52 Coastal Wetlands Land Use 3.19 N/A N/A
53 System of Rice Intensification Food 3.13 N/A $677.83
54 Walkable Cities Buildings and Cities 2.92 N/A $3,278.24
55 Household Recycling Materials 2.77 $366.92 $71.13
56 Industrial Recycling Materials 2.77 $366.92 $71.13
57 Smart Thermostats Buildings and Cities 2.62 $74.16 $640.10
58 Landfill Methane Buildings and Cities 2.50 $-1.82 $67.57
59 Bike Infrastructure Buildings and Cities 2.31 $-2,026.97 $400.47
60 Composting Food 2.28 $-63.72 $-60.82
61 Smart Glass Buildings and Cities 2.19 $932.30 $325.10
62 Women Smallholders Women and Girls 2.06 N/A $87.60
63 Telepresence Transport 1.99 $127.72 $1,310.59
64 Methane Digesters (Small) Electricity Generation 1.90 $15.50 $13.90
65 Nutrient Management Food 1.81 N/A $102.32
66 High-speed Rail Transport 1.52 $1,038.42 $368.10
67 Farmland Irrigation Food 1.33 $216.16 $429.67
68 Waste-to-Energy Electricity Generation 1.10 $36.00 $19.82
69 Electric Bikes Transport 0.96 $106.75 $226.07
70 Recycled Paper Materials 0.90 $573.48 N/A
71 Water Distribution Buildings and Cities 0.87 $137.37 $903.11
72 Biochar Food 0.81 N/A N/A
73 Green Roofs Buildings and Cities 0.77 $1,393.29 $988.46
74 Trains Transport 0.52 $808.64 $313.86
75 Ridesharing Transport 0.32 N/A $185.56
76 Micro Wind Electricity Generation 0.20 $36.12 $19.90
77 Energy Storage (Distributed) Electricity Generation N/A N/A N/A
77 Energy Storage (Utilities) Electricity Generation N/A N/A N/A
77 Grid Flexibility Electricity Generation N/A N/A N/A
78 Microgrids Electricity Generation N/A N/A N/A
79 Net Zero Buildings Buildings and Cities N/A N/A N/A
80 Retrofitting Buildings and Cities N/A N/A N/A