Related by context. Frequent words. (Click for all words.) 74 nitrogen oxide 72 sulfur dioxide emissions 70 nitrogen oxides 69 mercury emissions 69 emissions 67 carbon dioxide emissions 64 NOx 64 greenhouse emissions 63 greenhouse gas emissions 62 GHG emissions 62 emission 62 air pollution 61 CO2 emissions 60 Emissions 59 mercury pollution 59 carbon dioxide CO2 emissions 58 greenhouse gas emission 58 carbon emissions 58 greenhouse gases 58 greenhouse gasses 57 tailpipe emissions 57 particulate matter 57 sulfur dioxide 57 pollution 56 emission reductions 56 exhaust emissions 56 GHGs 56 reduce carbon emissions 56 pollutants 56 greenhouse gas 55 emission reduction 54 carbon dioxide 53 carbon emission 52 CO2 52 CO2 emission 52 ozone pollution 52 diesel exhaust 51 particulates 51 Clean Air 51 coal fired 50 volatile organic compounds 50 GHG 50 pollutant 50 carbon dioxide CO2 50 cleaner burning 50 global warming gases 48 reducing carbon emissions 47 smog 46 VOCs 46 cleaner fuels 46 Emission 46 diesel engines 46 combustion 46 soot 46 particulate 45 particle pollution 45 Air Pollution Control 45 EPA 45 heat trapping gases 45 ozone 44 polluting 44 scrubbers 44 Air Quality 43 low sulfur diesel 43 Environmental Protection Agency 43 Air Pollution 42 acid rain 42 nitrogen dioxide 42 emitters 42 polluter 42 carbon footprint 41 tailpipe 41 reduce greenhouse gas 41 Pollution 41 flue gas 41 CARB 40 polychlorinated biphenyls 40 smokestacks 40 polluters 40 renewables 40 renewable fuels 40 carbon 40 burning fossil fuels 40 exhaust fumes 40 gigawatts 40 nitrogen 40 fossil fuel 40 carbon capture 40 coal gasification 40 diesel 40 mercury 40 sulfur 40 IGCC 39 electric utilities 39 renewable 39 biomass 39 renewable energy 39 emitted 39 scrubber 39 methane 39 biodiesel