“Upgraders” are used to purify a form of gas described by this prefix to bring it closer to the methane content of natural gas. A 2004 DoE report lists 3-HPA and levulinic acid among the top 12 value-added chemicals derived from sources described by this prefix. A type of energy described by this prefix is combined with carbon capture and sequestration in a net zero strategy called BECCS. A form of (*) “char” described by this prefix useful for conditioning soil comes from pyrolysis of hemicellulose-rich “mass” described by this prefix. This prefix describes a type of diesel sourced from oil seeds, and more general “fuels” described by this prefix include corn ethanol. For 10 points, give this prefix that describes renewable energy derived from plants and other once-living matter. ■END■
ANSWER: bio- [accept biogas, biodiesel, biomass, bioenergy, biofuels, or biochar]
<VD, Chemistry>
= Average correct buzz position