Abstract: A thermal storage system includes a first block comprising (i) a bonded aggregate material, and (ii) between 0.01% and 10%, by weight, of graphite. A fluid transport via is disposed on or adjacent to at least a portion of an external surface of the first block and is in thermal coupling therewith. The fluid transport via presses against the first block with a force of at least 7 Newtons per meter. The graphite is disposed adjacent to at least said portion of said external surface so as to increase an aggregate rate of heat transfer over an entire volume of the first block.

Abstract: The invention provides in some aspects a thermal energy collection system comprising a first solar collector through which a first heat transfer fluid flows to absorb energy from sunlight as it passes through the first solar collector, and a second solar collector that collects energy from sunlight that has passed through the first solar collector. The first heat transfer fluid of the thermal energy collection system according to these aspects of the invention is in thermal coupling with the first solar collector, but not with the second solar collector. In other aspects, the invention provides a radiator system, comprising a multi-wall panel, an interior of which is in fluid coupling with, and that forms part of, a fluid circuit through which a first heat transfer fluid flows. A reflective surface is disposed in a vicinity of a second face of the multi-wall panel. Still other aspects of the invention provide a reflective film solar energy collector and a solar energy absorber.

Abstract: The invention provides, in some aspects, a thermal energy storage and retrieval system with a cavity containing a working fluid and a heat transfer surface disposed in the cavity transverse to a gravity field and in thermal coupling with an ice that is formed from and floating in the working fluid. The heat transfer surface transfers to that ice heat from a heat transfer medium that is thermally coupled to the heat transfer surface. According to aspects of the invention in which the ice is less dense than the working fluid, the heat transfer surface is disposed above (with respect to the gravity field) a region of the cavity where that ice is formed or inlet. According to aspects of the invention in which the ice is more dense than the working fluid, the heat transfer surface is disposed below that region.

Abstract: According to some aspects of the invention a heat pump includes first and second heat extraction units to extract heat from first and second heat sources in first and second temperature ranges, respectively, where the second temperature range is, on average, higher than the first temperature range. A fluid via defines a pathway through which the working fluid flows serially from the first heat extraction unit to the second heat extraction unit to the thermal storage unit. A pressure reduction stage is coupled to the via and serially disposed on the fluid circuit between the thermal store and the first heat extraction unit. In addition, either a compressor or a recuperator (or both) are coupled to the via and disposed on the fluid circuit between the first heat extraction unit and the second heat extraction unit.