The invention provides a process for removal of gaseous decomposition products from high temperature heat transfer fluid HTF of an operational solar thermal power plant having an HTF circuit, in which a volume increase of the HTF in the HTF circuit which is caused by incident solar radiation in an HTF-traversed solar field and consequent heating by day takes place regularly in a day-night cycle and the additional volume formed by the volume increase is collected from the HTF circuit in an expansion vessel, a portion of the additional volume of the HTF is transferred into a drainage vessel operated at relatively low pressure in which gaseous decomposition products and low-boiling constituents escape from the HTF, wherein the low-boiling constituents are condensed, and during the volume contraction of the HTF occurring during the night-time cooling a portion of the additional volume of the HTF is recycled from the drainage vessel into the expansion vessel and from the expansion vessel into the HTF circuit, wherein the volumes in the expansion vessel and the drainage vessel becoming vacant as a result of the transferrals of the HTF are filled with inert gas.

A method for operating a hybrid collector solar system includes a heat transfer agent, which is present in a buffer accumulator, that passes via a pump into a thermal solar collector of the hybrid collector in order to heat the heat transfer agent. The pump is connected into a feed line that connects the buffer accumulator to the thermal solar collector. The hybrid collector solar system is partially filled with the heat transfer agent so that part of the hybrid collector solar system is not filled and so that the heat transfer agent is moved back and forth between the thermal solar collector and the buffer accumulator via the feed line depending on its temperature, thereby realizing an oscillating method of operation.

A method for operating a hybrid collector solar system includes a heat transfer agent, which is present in a buffer accumulator, that passes via a pump into a thermal solar collector of the hybrid collector in order to heat the heat transfer agent. The pump is connected into a feed line that connects the buffer accumulator to the thermal solar collector. The hybrid collector solar system is partially filled with the heat transfer agent so that part of the hybrid collector solar system is not filled and so that the heat transfer agent is moved back and forth between the thermal solar collector and the buffer accumulator via the feed line depending on its temperature, thereby realizing an oscillating method of operation.

A method for improving the efficiency of a solar heating system based on absorbing heat from solar radiation into the outer surface of a concrete wall. The heat transfer device makes use of a fluid in a tube system to transfer heat from the outside of the wall to the inside of the wall. The inside wall is then used to heat air that is passed over it, and that air is then used to heat up a heat storage system.

The invention provides a process for removal of gaseous decomposition products from high temperature heat transfer fluid HTF of an operational solar thermal power plant having an HTF circuit, in which a volume increase of the HTF in the HTF circuit which is caused by incident solar radiation in an HTF-traversed solar field and consequent heating by day takes place regularly in a day-night cycle and the additional volume formed by the volume increase is collected from the HTF circuit in an expansion vessel, a portion of the additional volume of the HTF is transferred into a drainage vessel operated at relatively low pressure in which gaseous decomposition products and low-boiling constituents escape from the HTF, wherein the low-boiling constituents are condensed, and during the volume contraction of the HTF occurring during the night-time cooling a portion of the additional volume of the HTF is recycled from the drainage vessel into the expansion vessel and from the expansion vessel into the HTF circuit, wherein the volumes in the expansion vessel and the drainage vessel becoming vacant as a result of the transferrals of the HTF are filled with inert gas.

The invention provides a process for removal of gaseous decomposition products from high temperature heat transfer fluid HTF of an operational solar thermal power plant having an HTF circuit, in which a volume increase of the HTF in the HTF circuit which is caused by incident solar radiation in an HTF-traversed solar field and consequent heating by day takes place regularly in a day-night cycle and the additional volume formed by the volume increase is collected from the HTF circuit in an expansion vessel, a portion of the additional volume of the HTF is transferred into a drainage vessel operated at relatively low pressure in which gaseous decomposition products and low-boiling constituents escape from the HTF, wherein the low-boiling constituents are condensed, and during the volume contraction of the HTF occurring during the night-time cooling a portion of the additional volume of the HTF is recycled from the drainage vessel into the expansion vessel and from the expansion vessel into the HTF circuit, wherein the volumes in the expansion vessel and the drainage vessel becoming vacant as a result of the transferrals of the HTF are filled with inert gas.

A method for improving the efficiency of a solar heating system based on absorbing heat from solar radiation into the outer surface of a concrete wall. The heat transfer device makes use of a fluid in a tube system to transfer heat from the outside of the wall to the inside of the wall. The inside wall is then used to heat air that is passed over it, and that air is then used to heat up a heat storage system.

A method for improving the efficiency of a solar heating system based on absorbing heat from solar radiation into the outer surface of a concrete wall. The heat transfer device makes use of a fluid in a tube system to transfer heat from the outside of the wall to the inside of the wall. The inside wall is then used to heat air that is passed over it, and that air is then used to heat up a heat storage system.

A solar thermal collecting system, including at least one solar thermal collector and a pressure-adjusting module, is provided. The solar thermal collector includes a container, a light-transmissive cover that seals the container, and a plurality of solar thermal collecting pipes. The solar thermal collecting pipes are installed in the container, so as to allow a heat transfer material to flow therein. The outer surfaces of the solar thermal collecting pipes are correspondingly deposited with solar selective coatings for absorbing solar radiation energy, transforming the radiation energy into thermal energy, and transmitting thermal energy to the heat transfer material flowing in the solar thermal collecting pipes. The pressure-adjusting module controls the heat loss rate of the solar thermal collector by adjusting the air pressure inside the solar thermal collector and controlling the direction of air circulation to flow in or out of the solar thermal collector.

A heat driven liquid close-loop automatic circulating system is provided. This system circulates the liquid in a close-loop by the collected heat in the loop. The system may operate without external power for the pump. The heat driven liquid close-loop automatic circulating system may employ a modified self-powered pump for heated liquid. The pump includes an airtight container for containing the heated liquid, a inlet and a outlet of the heated liquid, further more the modified self-powered pump has a breathing channel with a liquid vapor condensing and reflux structure. The heat driven liquid close-loop automatic circulating system may be a solar heated liquid close-loop automatic circulating system with a solar heat collector.