A system for converting a biomass into a biofuel including a biomass processing station arranged to receive the biomass from a biomass harvester, output the biomass to a hydrothermal liquefaction (HTL) converter, and receive a processed biomass from the HTL converter. The system includes a conduit arranged to transport the biomass from the biomass processing station to the HTL converter and transport the processed biomass from the HTL converter to the biomass processing station. The HTL converter includes a heat exchanger arranged to transfer thermal energy from a geothermal heat source to the biomass to convert the biomass into the processed biomass. The system also includes a controller arranged to monitor conditions of the biomass at locations along the conduit and adjust operations of components along the conduit to, thereby, adjust the conditions of the biomass at one or more locations along the conduit.

A system comprising a collocated thermal plant, water source, CO.sub.2 source and biomass growth module is disclosed. A method of improving the environment by utilizing the system is disclosed.

The presently disclosed subject matter relates to an industrial system for processing various plant materials to produce marketable materials. Particularly, the system integrates subcritical water extraction technology and includes a pre-processing module and a two-stage extractor (processing module) with constant control of temperature, pressure, and/or residence time. In some embodiments, the final product of the disclosed system can include feedstock constituents for biofuel production (sugars and/or oil), biochar, raw materials for various industries (such as pulp for manufacturing paper or cellulose for use in various industries). The disclosed system can be modular or non-modular, stationary or mobile, and can include prefabricated elements with programmed automatic or manual operation so that it can be easily moved and/or assembled on site.