The present invention provides a method for improving power generation efficiency of a solar cell, comprising: providing a synergistic structure for allowing the solar cell to receive light through thereof, wherein the synergistic structure is a three-dimensional structure; the three-dimensional structure has a surface area that is larger than a surface area of the solar cell, a refractive index of substances that used to construct the three-dimensional structure is higher than a refractive index of environmental substances around the solar cell, and improving an interface condition of the solar cell could increase light introduced into the solar cell and improving power generation efficiency of the solar cell.

A pumpless solar energy-based air heater includes a body housing a chamber surrounded by a heat conducting medium; an intake pipe to draw cool air into the chamber; and one or more exit pipes to push warm air out from the chamber, the one or more exit pipes having one or more structures within the interior of the one or more exit pipes to create a low friction factor for the air flowing upwards in the exit pipe while creating a high friction factor for the air attempting to move downward, thereby ensuring air flow in an upward direction; a pressure difference is created between an entry point of the intake pipe and an end point of the one or more exit pipes, thereby eliminating the need for a pump or a fan.

A heat transfer system includes a conduit having open first and second ends, first and second thermal exchange segments disposed in-between and in fluid communication with the ends, and a means for adding fluid to the first end. The first thermal exchange segment is disposed underneath and in thermal communication with the ground, a body of water, or other location with a different temperature. The first and second ends are arranged above all other section of conduit and relative to one another so that they are communicating vessels and a change in fluid level in one changes the fluid level in the other. The means for adding fluid to the first end of the conduit causes fluid to flow freely from the first end to the second end and fluid level to rise in the second overcoming any hydrostatic pressure in the system without a pump disposed along the conduit.

A building-integrated solar energy system is disclosed that comprises an evacuated closed-loop conduit network circulating a working fluid through a solar thermal collector and at least one heat usage device, wherein the effective entirety of the surfaces of the closed-loop conduit network are in contact with the working fluid such that phase change occurs whenever heat energy is added by the solar thermal collector or removed by a heat usage device. The working fluid is adiabatically isolated and contained in a low pressure environment within the closed-loop conduit network. The full surface contact and low-pressure isolation of the working fluid dramatically reduces temperature differentials and energy losses, allowing for highly efficient and cost-effective heat collection and distribution.

A building-integrated solar energy system is disclosed that comprises an evacuated closed-loop conduit network circulating a working fluid through a solar thermal collector and at least one heat usage device, wherein the effective entirety of the surfaces of the closed-loop conduit network are in contact with the working fluid such that phase change occurs whenever heat energy is added by the solar thermal collector or removed by a heat usage device. The working fluid is adiabatically isolated and contained in a low pressure environment within the closed-loop conduit network. The full surface contact and low-pressure isolation of the working fluid dramatically reduces temperature differentials and energy losses, allowing for highly efficient and cost-effective heat collection and distribution.

The disclosure relates to a thermosiphon system operable to consistently maintain the permafrost and active frost layer in a frozen condition to adequately support buildings and other structures. During cooler seasons, the thermosiphon system uses a passive refrigeration cycle to efficiently maintain the frozen layers using the cold air. When the air temperature rises during the warmer months, the system transitions into an active refrigeration mode that uses a refrigeration system to minimize thawing or degradation of the permafrost and active frost layers.

The disclosure relates to a thermosiphon system operable to consistently maintain the permafrost and active frost layer in a frozen condition to adequately support buildings and other structures. During cooler seasons, the thermosiphon system uses a passive refrigeration cycle to efficiently maintain the frozen layers using the cold air. When the air temperature rises during the warmer months, the system transitions into an active refrigeration mode that uses a refrigeration system to minimize thawing or degradation of the permafrost and active frost layers.

A pumpless solar energy-based air heater includes a body housing a chamber surrounded by a heat conducting medium; an intake pipe to draw cool air into the chamber; and one or more exit pipes to push warm air out from the chamber, the one or more exit pipes having one or more structures within the interior of the one or more exit pipes to create a low friction factor for the air flowing upwards in the exit pipe while creating a high friction factor for the air attempting to move downward, thereby ensuring air flow in an upward direction; a pressure difference is created between an entry point of the intake pipe and an end point of the one or more exit pipes, thereby eliminating the need for a pump or a fan.

A gravity driven Thermosiphon solar water heating system to harness solar insolation in low sunshine regions. This innovatory system uses CO.sub.2 as the working fluid to collect even mild sunlight to heat the water in sub-zero temperature areas. This solar water heater harnesses solar energy by fitting U-shaped copper heat removal pipes in evacuated glass tubes. This system works automatically by natural thermosiphon circulation force caused by density difference of supercritical CO.sub.2 at different temperatures. This innovatory solar water heater can perform in ice cold temperature areas where water based systems cease to function after freezing.

A gravity driven Thermosiphon solar water heating system to harness solar insolation in low sunshine regions. This innovatory system uses CO.sub.2 as the working fluid to collect even mild sunlight to heat the water in sub-zero temperature areas. This solar water heater harnesses solar energy by fitting U-shaped copper heat removal pipes in evacuated glass tubes. This system works automatically by natural thermosiphon circulation force caused by density difference of supercritical CO.sub.2 at different temperatures. This innovatory solar water heater can perform in ice cold temperature areas where water based systems cease to function after freezing.