Second-generation biofuels are fuels manufactured from various types of biomass. Biochar is charcoal created by pyrolysis of biomass waste. There is some debate in the classification of certain biomass feedstock as wastes. Pyrolysis hold promise for conversion of waste biomass into useful liquid fuel. The changes in oxygenation are considered consistent with measurements of higher algal biomass and productivity. There is ongoing research involving algae or algae-derived biomass. Sulfates occur as microscopic particles (aerosols) resulting from fossil fuel and biomass combustion. Most animals rely on the biomass and energy produced by plants through photosynthesis. Pyrolysis is the basis of several methods for producing fuel from biomass, i.e. lignocellulosic biomass. Algal bio-oil had better qualities in many aspects than those produced from lignocellulosic biomass. Chlorophyll are photosynthetic pigments that are often used as an indicator of phytoplankton biomass. Furthermore, the country has the potential for geothermal, solar, wind, biomass and ocean energy. Genetic engineering may enable hydrogen to be generated in bioreactors from woody biomass. Maize cobs are also used as a biomass fuel source. Xcel Energy has contracts for about 110 megawatts of electricity from biomass generators.