Disclosed is a lighter than air vehicle comprising: an envelope (34) containing a lighter than air gas (22), at least part of the envelope (34) admitting the passage of light (28) through the at least part of the envelope (34); and means for selectively redirecting the light (28) which passes through the at least part of the envelope (34). The vehicle may further comprises a plurality of devices (44, 50) for using incident light (28). The means for selectively redirecting the light (28) may be for selectively redirecting the light (28) onto a selected device (44, 50), for example, by switching the positions of two or more devices (44, 50) into the path of the light (28).

The use of photovoltaic (PV) cells to convert solar energy to electricity is becoming increasingly prevalent; however, there are still significant limitations associated with the widespread adoption of PV cells for electricity needs. There is a clear need for a high efficiency solar power system that supplies electricity at a competitive cost and that provides for an on-demand supply of electricity as well as energy storage. By combining aspects of concentrated solar power and concentrated photovoltaics, the present invention provides a device that enables the conversion of sunlight to electricity at very high efficiencies and that enables the transmission of thermal energy to heat storage devices for later use. The disclosed device enables transmissive CPV through the use of a multijunction PV cell mounted on a transparent base. The use of a multijunction cell allows for highly efficient absorption of light above the bandgap of the lowest bandgap subcell. The transparent base permits transmission of a high percentage of the remaining light below the bandgap of the lowest bandgap subcell. The present invention also discloses a method of generating electricity through the use of a transmissive CPV device. Sunlight is concentrated onto one or more surfaces of the device. High energy light is absorbed by a multijunction PV cell and converted directly to electricity, while low energy light is transmitted through the device into a thermal storage device, which may then be coupled to a heat engine to generate dispatchable electricity.

Methods and systems are provided for air conditioning, capturing combustion contaminants, desalination, and other processes using liquid desiccants.

A wafer precursor for creating photovoltaic (PV) concentrator modules and a method for fabricating solar concentrator modules using the wafer precursor. The method includes providing a crystalline silicon wafer substrate that can be used to make multiple concentrator cells to be incorporated into concentrator modules. The method also includes applying fingers as horizontal grid lines onto the crystalline silicon wafer substrate. The method also includes applying bus bars onto the crystalline silicon wafer substrate to form separate top grid structures. The number of separate top grid structures is at least two when the concentrator module is part of an optical system that has a concentration ratio of between about 8 and about 16 times sunlight. The number of top grid structures is at least three when the concentrator module is part of an optical system that has a concentration ratio of between about 17 and about 50.

A device for converting electromagnetic radiation into electricity comprises an expander that includes a conical shape having an axis and a curved surface that is configured to reflect electromagnetic radiation away from the axis to expand a beam of the electromagnetic radiation; and one or more energy conversion components configured to receive a beam of electromagnetic radiation expanded by the expander, and to generate electricity from the expanded beam of electromagnetic radiation. With the expander's curved surface, a beam of electromagnetic radiation that is highly concentratedhas a large radiation fluxmay be converted into a beam that has a larger cross-sectional area. Moreover, one can configure, if desired, the curved surface to provide a substantially uniform distribution of radiation across the expanded cross-sectional area. With such an expanded beam the one or more energy conversion components can efficiently convert some of the electromagnetic radiation into electricity.

A heat transfer device having a working fluid capable of circulating around a fluid flow path, the circulation around the fluid flow path bringing the working fluid in and out of thermal contact with a heat source, the heat transfer device comprising: a fluid containing portion internally defining a working fluid flow path; a heat source at least partially in thermal contact with the fluid containing portion; a gas substance generator at least partially within the fluid containing portion, and arranged to generate bubbles of vapor capable of driving the working fluid along a portion of the working fluid flow path in thermal contact with the heat source; wherein, in use, the driven working fluid absorbs heat from the heat source and transports the heat away from the heat source; and the driven working fluid returns to the gas substance generator to be recycled about the fluid flow path.

A wafer precursor for creating photovoltaic (PV) concentrator modules and a method for fabricating solar concentrator modules using the wafer precursor. The method includes providing a crystalline silicon wafer substrate that can be used to make multiple concentrator cells to be incorporated into concentrator modules. The method also includes applying fingers as horizontal grid lines onto the crystalline silicon wafer substrate. The method also includes applying bus bars onto the crystalline silicon wafer substrate to form separate top grid structures. The number of separate top grid structures is at least two when the concentrator module is part of an optical system that has a concentration ratio of between about 8 and about 16 times sunlight. The number of top grid structures is at least three when the concentrator module is part of an optical system that has a concentration ratio of between about 17 and about 50.

A self-powered light seeking apparatus and method for directing a target-plane towards a light source. The apparatus includes a photovoltaic powering arrangement configured to convert light energy into a driving current to power an actuator. The actuator is coupled to a support platform and is wired to the photovoltaic powering arrangement such that the polarity of the driving current causes the actuator to drive the target-plane towards alignment with the light source. A solar energy collection system including a photoelectric assembly for generating electricity from light incident upon an active area; a light concentrator comprising a substantially planar reflective surface subtending an angle to the active area such that light arriving along a line perpendicular to the active area and striking the reflective surface is reflected onto the active area; and a cooling unit configured to maintain the photoelectric assembly at an efficient operating temperature.

Methods and apparatuses to increase a speed of airflow through a heat exchanger are described. An optoelectronic device comprising a heat exchanger is coupled to an airflow accelerator. The airflow accelerator comprises a surface to guide the airflow towards the heat exchanger. An optical element is coupled to concentrate light onto the optoelectronic device. The size of the surface, position of the airflow accelerator relative to the heat exchanger, or both can determine increase in speed of the airflow. A photovoltaic (PV) system comprises rows of receivers; rows of optical elements to concentrate light onto the receivers, and rows of airflow accelerators coupled to the receivers to increase the speed of airflow through heat exchangers. The airflow can be deflected by an airflow accelerator towards a heat exchanger. A wind load can be reduced by the airflow accelerator.

A panel (105) is provided for utilizing solar energy, especially in the form of panels designed as roof tiles (101), wherein the heat is transferred from panel to fluid or vice versa. On this panel one or more solar cell panels (107) can be provided so that it is cooled effectively during operation, while heat energy simultaneously may be utilized. Panels, for example designed as roof tiles, individually or assembled, are mounted on roofing battens (110) suitable for the purpose, and connected to electrical connection points and bushings for fluid transport. The roofing battens (110) are mounted on furring ring strips (112) in the usual way. Some furring strips are used for connection of electrical conductors in the flooring battens (112) and any fluid circuits in the flooring battens (110). The construction facilitates installing and maintenance.