NOVELTY - Method for integrated solar driven chemical plant, involves: converting chemical reactant including particles of biomass, in solar driven chemical reactor (306) into synthesis gas using concentrated solar energy; supplying synthesis gas for catalytic conversion of the gas in methanol synthesis plant to methanol; and cycling between operational and idle state for a number of methanol trains in methanol synthesis plant depending upon amount of synthesis gas generated; where a control system for reactor sends signals to and receives feedback from control system for methanol synthesis plant.    USE - For producing methanol useful for producing hydrocarbon fuel i.e. gasoline (claimed), and liquid hydrocarbon fuels such as diesel.    ADVANTAGE - The chemical plant is an integrated biorefinery that converts biomass-to-gasoline based on a solar thermal chemical reactor platform. The integrated biorefinery performs solar thermochemical biomass gasification to synthesis gas with a subsequent catalytic conversion of the synthesis gas to methanol, followed by the methanol to gas process to produce gasoline. The process uses concentrated solar thermal power to provide the energy needed to drive the gasification process as well as other integrated process through the use of waste heat. The integrated solar driven chemical plant manages variations in solar energy, and it uses an external source of energy (solar) to provide the energy required for reaction, so none of the biomass need be consumed to achieve the conversion. This result in significantly higher yields of gallons of gasoline per biomass ton than previous technologies. The energy source used to drive the conversion is renewable and carbon free. The control system balances the gasification reaction of biomass particles with the available concentrated solar energy and additional variable parameters including a fixed range of particle sizes, operating temperature of the chemical reactor, and residence time of the particles in a reaction zone in the chemical reactor so that an overall biomass particle conversion remains above a threshold set point of greater than 90 percent of the carbon content of the particles into reaction products that include hydrogen and carbon monoxide gas with low tar production of less than 200 mg/Nm3 and preferably less than 50 mg/Nm3, where the residence time of the particles of biomass in the reaction zone in the chemical reactor is 0.01-5 seconds. Also, the methanol synthesis control system control parameters including chemistry, temperature, and pressure of the methanol synthesis plant during idle non-production periods of time so that the methanol synthesis plant has little to no loss in catalytic activity or throughput over the plant's lifetime. This allows for the protection of the catalyst, as long as the syngas and product methanol gas are kept at a certain temperature and pressure, then the gases remains vaporized and does not condense on the catalyst prolonging the life of the catalyst.    DETAILED DESCRIPTION - Method for an integrated solar driven chemical plant, involves: converting a chemical reactant, including particles of biomass, in a solar driven chemical reactor (306) into synthesis gas containing carbon monoxide and hydrogen using concentrated solar energy to drive the conversion of the chemical reactant; supplying the synthesis gas for a catalytic conversion of the synthesis gas in a methanol synthesis plant to methanol; and cycling between an operational state and an idle state for a number of methanol trains in the methanol synthesis plant depending upon an amount of synthesis gas generated in the solar driven chemical reactor; where a control system for the chemical reactor sends control signals to and receives feedback from a control system for the methanol synthesis plant.    DESCRIPTION OF DRAWING(S) - The figure shows a view of an example solar tower with receivers and solar energy concentrating fields.    Solar tower (300)    Solar thermal receiver (302)    Solar energy concentrating field (304)    Solar driven chemical reactor (306)