Biomass (e.g., plant biomass, animal biomass, and municipal waste biomass) is processed to produce useful products, such as fuels. For example, systems are described that can use feedstock materials, such as cellulosic and/or lignocellulosic materials, to produce ethanol and/or butanol, e.g., by fermentation.

Biomass (e.g., plant biomass, animal biomass, and municipal waste biomass) is processed to produce useful products, such as fuels. For example, systems are described that can use feedstock materials, such as cellulosic and/or lignocellulosic materials, to produce ethanol and/or butanol, e.g., by fermentation.

Systems and methods for selectively producing steam from solar collectors and heaters, for processes including enhanced oil recovery, are disclosed herein. A system in accordance with a particular embodiment includes a water source, a solar collector that includes a collector inlet, a collector outlet, and a plurality of solar concentrators positioned to heat water passing from the collector inlet to the collector outlet, a fuel-fired heater, a steam outlet connected to an oil field injection well, and a water flow network coupled among the water source, the solar collector, the heater, and the steam outlet. The system can further include a controller operatively coupled to the water flow network and programmed with instructions that, when executed, direct at least one portion of the flow through the solar collector and the fuel-fired heater in a first sequence, and direct the at least one portion or a different portion of the flow through the solar collector and the fuel-fired heater in a second sequence different than the first sequence.

The invention provides circular processes using siloxanes as high-temperature heat transfer fluid (HTF), wherein the siloxanes go over from the state of the supercooled liquid into the state of the high-density supercritical fluid by means of heat uptake without a phase transition and energy is then transferred as energy without a phase transition.

A hairpin heat exchanger (1), wherein the bundle of parallel U-bent tubes (2) is extended out of the exchanger and connected, via bent tubes (11), respectively beyond an end of the internal shell (3) and of the external shell (4) at the first straight section to a first header (9) distributing the first fluid to the bundle of straight tubes (2) and beyond an end of the internal shell (3) and of the external shell (4) at the second straight section to a second header (10) collecting the first fluid under the form of liquid, vapor or a mixture liquid/vapor from the bundle of straight tubes (2).

A device for storage and exchange of thermal energy of solar origin, which device is configured to receive a concentrated solar radiation using an optical system of beam down type, which device comprises: a containment casing which defines an internal compartment and has an upper opening configured to allow entry of the concentrated solar radiation, which opening puts in direct communication the internal compartment with the external environment having no closure or screen means; a bed of fluidizable solid particles, received within the internal compartment, which bed has an irradiated operative region directly exposed, in use, to the concentrated solar radiation that enters through said opening and a heat accumulation region adjacent to said operative region; fluidization elements of the bed of particles, configured to feed fluidization air within the compartment, which fluidization means is configured to determine different fluid-dynamic regimens in the operative region and in the accumulation region, based upon different fluidization speeds, wherein, in use, the particles of the operative region absorb thermal energy from the solar radiation and they give it to the particles of the accumulation region.

Separators and mixers for delivering controlled-quality solar-generated steam over long distances for enhanced oil recovery, and associated systems and methods. A representative method includes heating water to steam at a solar field, separating a liquid fraction from the steam, directing the steam toward a target steam user via a first, steam conduit, and directing the liquid fraction toward the target steam user in parallel with the steam via second, liquid fraction conduit. The method can further include mixing the liquid fraction and the steam before delivering the combined liquid fraction and steam to the target user.

Energy storage systems are disclosed. The systems may store energy as heat in a high temperature liquid, and the heat may be converted to electricity by absorbing radiation emitted from the high temperature liquid via one or more photovoltaic devices when the high temperature liquid is transported through an array of conduits. Some aspects described herein relate to reducing deposition of sublimated material from the conduits onto the photovoltaic devices.

A solar powered boiler assembly for producing steam with solar energy includes a bowl that is positioned in the ground. A boiler is positioned in the bowl and the boiler has a fluid therein. A dome is removably positioned on the bowl. A plurality of lenses each extends through the dome such that each of the lenses is exposed to sunlight. Each of the lenses focuses the sunlight onto the boiler to heat the boiler. In this way the boiler produces steam by heating the fluid therein. A reflector is coupled to the dome and the reflector is comprised of a light reflecting material for reflecting sunlight onto the lenses.

A steam generator system configured to burn hydrogen and oxygen at stoichiometry along with a high-pressure water and steam. Said steam generator system comprise a hydrogen source, an oxygen source, a nitrogen source, a water source, a steam source, a hydrogen-oxygen handling unit, a cooling unit, a one or more H2-O2 steam generators and a control unit. Said steam generator system is configured to provide said hydrogen source to said hydrogen-oxygen handling unit through an oxygen passage, said oxygen source to said hydrogen-oxygen handling unit through a hydrogen passage, and said nitrogen source to selectively purge said oxygen passage and said hydrogen passage. Said water source provide water to said cooling unit. Said cooling unit is configured to receive said water source and said steam source.