Systems and methods for falling particle receivers are disclosed that include shield or deflector structures around the receiver aperture to reduce wind effects and/or heat losses from the falling particles. External and internal structures are disclosed that can be tailored to reduce particle, thermal, and radiative losses from within the cavity receiver due to external wind and the falling particles that are irradiated within the receiver. Structures of varying shapes, sizes, and composition (transparent, reflective) are described.

Systems and methods for falling particle receivers are disclosed that include shield or deflector structures around the receiver aperture to reduce wind effects and/or heat losses from the falling particles. External and internal structures are disclosed that can be tailored to reduce particle, thermal, and radiative losses from within the cavity receiver due to external wind and the falling particles that are irradiated within the receiver. Structures of varying shapes, sizes, and composition (transparent, reflective) are described.

The invention relates to a method for operating a system at an operating temperature of between 300° C. and 500° C., using a heat transfer fluid comprising branched siloxanes of general formula (I) (R.sub.3SiO.sub.1/2), (SiO.sub.4/2) in which w represents integral values of between 4 and 20, z represents integral values of between 1 and 15, and R represents a methyl group, the sum of the fractions of all siloxanes of general formula (1) being at least 95 mass %, in relation to the whole heat transfer fluid.

A thermal receiver, such as a solar flux thermal receiver, is disclosed comprising a modular arrangement of arrayed microchannels or micropins to heat a working fluid by heat transfer. Disclosed solar receivers provide a much higher solar flux and consequently a significant reduction in thermal losses, size, and cost, relative to known receivers. Unit cell receivers can be numbered up and combined in parallel to form modules, and modules combined to form full scale receivers.

Provided are solar collection energy storage and energy conversion or chemical conversion systems. Also provided are tubing components, such as for solar receivers, including Mo and having a MoSiB coating on an external surface. The systems can include a solar receiver containing a heat transfer material or chemically reacting material and can operate at temperatures of 700° C. or higher. The solar receiver can include tubing components selected from a Mo tubing component, a MAX phase material tubing component, a MoSiB composite tubing component, or a combination thereof. The Mo component, when present, can include a coating on surfaces of the Mo component that operate above 700° C.

Provided are solar collection energy storage and energy conversion or chemical conversion systems. Also provided are tubing components, such as for solar receivers, including Mo and having a MoSiB coating on an external surface. The systems can include a solar receiver containing a heat transfer material or chemically reacting material and can operate at temperatures of 700° C. or higher. The solar receiver can include tubing components selected from a Mo tubing component, a MAX phase material tubing component, a MoSiB composite tubing component, or a combination thereof. The Mo component, when present, can include a coating on surfaces of the Mo component that operate above 700° C.

A branched polysiloxane compound and methods for its preparation are disclosed. The branched polysiloxane compound may be used as a heat transfer fluid.

A solar environmental control system includes a solar powered apparatus and a heat transfer apparatus. The solar collection apparatus includes a solar collector for absorbing solar energy, a heat storage medium, and a generator. A heat transfer fluid circulates between the solar collector, the heat storage medium, and the generator.

A solar environmental control system includes a solar powered apparatus and a heat transfer apparatus. The solar collection apparatus includes a solar collector for absorbing solar energy, a heat storage medium, and a generator. A heat transfer fluid circulates between the solar collector, the heat storage medium, and the generator.

A nickel-chromium-aluminum alloy includes (in mass %) 12 to 30% chromium, 1.8 to 4.0% aluminum, 0.1 to 7.0% iron, 0.001 to 0.50% silicon, 0.001 to 2.0% manganese, 0.00 to 1.00% titanium, 0.00 to 1.10% niobium, 0.00 to 0.5% copper, 0.00 to 5.00% cobalt, in each case 0.0002 to 0.05% magnesium and/or calcium, 0.001 to 0.12% carbon, 0.001 to 0.050% nitrogen, 0.001 to 0.030% phosphorus, 0.0001 to 0.020% oxygen, max. 0.010% sulfur, max. 2.0% molybdenum, max. 2.0% tungsten, and a remainder of nickel with a minimum content of 50% and the usual process-related impurities for use in solar power towers, using chloride and/or carbonate salt melts as a heat transfer medium, wherein in order to ensure a good processability, the following condition must be met: F.sub.V 0.9 with F.sub.V=4.88050−0.095546*Fe−0.0178784*Cr−0.992452*Al−1.51498*Ti−0.506893*Nb+0.0426004*Al*Fe, where Fe, Cr, Al, Ti, and Nb are the concentration of the respective elements in mass %.