A method and process is described for producing negative carbon fuel. In its broadest form, a carbon-containing input is converted to combustible fuels, refinery feedstock, or chemicals and a carbonaceous solid concurrently in separate and substantially uncontaminated form. In an embodiment of the invention, biomass is converted via discrete increasing temperatures under pressure to blendable combustible fuels and a carbonaceous solid. The carbonaceous solid may be reacted to synthesis gas, sold as charcoal product, carbon credits, used for carbon offsets, or sequestered.