Criteria pollutant emissions, and especially NOx emissions, are major considerations when modifying any combustion system. The links at left summarize the issues associated with criteria pollutant emissions, some experimental highlights from laboratory investigations of such emissions, and conclusions regarding NOx emissions. The general guideline for criteria pollutant emissions is:
Fuels with low nitrogen contents and high volatile yields (most woody fuels) generally are more effective in reducing NOx emissions than high-nitrogen fuels. Most biomass fuels will reduce SOx emissions.