TECHNOLOGY FOCUS - CHEMICAL ENGINEERING - Preferred Process: The heat from the solar thermal energy source is used to generate electricity to operate at high temperature steam electrolysis process used in the generation of hydrogen. It is used to generate hydrogen by the hybrid sulfur process, sulfur-iodine cycle, or zinc-zinc oxide cycle. Hydropyrolysis is carried out in sequential steps in each of which the carbonaceous material is heated to greater than or equal to 800 degrees C, and is then quenched; and the pyrolysis products are separated, where each step is completed in not greater than 2 seconds. It is carried out at greater than or equal to 800 degrees C with hydrogen heated to a temperature to provide heating at a rate of not less than 500 degrees C/s. Hydropyrolysis is carried out using hydrogen as a quenching agent in each step. Quenching is carried out below 400 degrees C. Heat is supplied from a solar thermal energy source during periods of available solar radiation and from a fossil fuel source when solar radiation is not available. Preferred Component: The hydropyrolysis unit includes a conduit for passing the carbonaceous feed directly through the solar furnace; a heat transfer loop from the solar furnace to the reactor containing a heat transfer medium for transferring heat from the solar furnace to the reactor; a heat transfer loop from the solar furnace to a feed heater through which the carbonaceous feed passes before entering the reactor through the reactor feed inlet; mechanism for generating steam (14) using heat from the solar thermal energy source and a steam electrolysis unit for the generation of hot hydrogen; and mechanism for transferring heat from the solar thermal energy source to a hydrogen generator (A-D) comprising a hybrid sulfur process unit, sulfur-iodine cycle unit, or zinc-zinc oxide cycle unit. It comprises heat transfer loop passing through the solar furnace and containing a heat exchange medium; heat exchanger in the heat transfer loop for transferring heat from the heat exchange medium in the loop to the reactor at 800-1500 degrees C; heat exchanger in the heat transfer loop for transferring heat from the heat exchange medium in the loop to a hot generator of hot hydrogen; and a conduit for hot hydrogen from the hydrogen generator to the hot hydrogen inlet of the reactor. The heat exchanger in the heat transfer loop transfers heat from the heat exchange medium in the loop to a steam generator (12) to generate high temperature steam, or to a hybrid sulfur process unit, sulfur-iodine cycle unit, or zinc-zinc oxide cycle unit as hydrogen generator. The hydropyrolysis unit includes mechanism for transferring steam from the steam generator to the electrolysis unit. It includes mechanism for transferring steam from steam generator to the hydrogen generator. The hydropyrolysis unit includes steam methane reformer as hydrogen generator; and mechanism for transferring steam from steam generator to the methane steam reformer. EXAMPLE - No suitable example given.