A method for installing a ground heat exchange pipe uses a drive mechanism driven downwardly by a drive head including an elongate drive mandrel for driving a portion of heat exchange pipe into the ground. The pipe is attached to an inserting tool connected to the drive mandrel so that the tool carries the portion of heat exchange pipe into the ground. The mandrel engages the inserting tool which includes a base and tie attached to a portion of the pipe and drives the inserting tool into unbroken ground to a finite depth and then the drive head extracts the mandrel for reuse on the next installation leaving the inserting tool behind with the heat exchange pipe. The inserting tool includes side components engaging the heat exchange pipe and protecting it from damage as the heat exchange pipe is driven into the ground. A fluid supply duct can be provided in the mandrel.

A geothermal heat exchange apparatus is disclosed that includes a central conduit, a plurality of pipes, at least one fitting and a joint. The geothermal heat exchange apparatus is preassembled for insertion into a bore hole and for connection to a supply primary pipe and a return primary pipe that are in fluid communication with a heat pump. The geothermal heat exchange apparatus includes the plurality of pipes in a helical arrangement around the central conduit for geothermal heat exchange. The at least one fitting is fixedly connected to a first end portion of the central conduit in the bore hole.

A geothermal heat exchange apparatus is disclosed that includes a central conduit, a plurality of pipes, at least one fitting and a joint. The geothermal heat exchange apparatus is preassembled for insertion into a bore hole and for connection to a supply primary pipe and a return primary pipe that are in fluid communication with a heat pump. The geothermal heat exchange apparatus includes the plurality of pipes in a helical arrangement around the central conduit for geothermal heat exchange. The at least one fitting is fixedly connected to a first end portion of the central conduit in the bore hole.

A geothermal well is provided including a first tube including at least one opening in a first depth; a second tube having a closed bottom in a second depth; and a third tube having a closed bottom in a third depth. The first tube is inside the second tube, which is inside the third tube, wherein the first tube has at least one opening in fluid communication with a first interspace between the first tube and the second tube; wherein the third depth and the first depth are smaller than the second depth. Through-holes are formed in the second tube above the bottom of the third tube, which allow fluid communication between the first interspace and a second interspace between the second tube and the third tube. A first sealing element and a heat insulating material are disposed in the first interspace above the through-holes.

A geothermal well is provided including a first tube including at least one opening in a first depth; a second tube having a closed bottom in a second depth; and a third tube having a closed bottom in a third depth. The first tube is inside the second tube, which is inside the third tube, wherein the first tube has at least one opening in fluid communication with a first interspace between the first tube and the second tube; wherein the third depth and the first depth are smaller than the second depth. Through-holes are formed in the second tube above the bottom of the third tube, which allow fluid communication between the first interspace and a second interspace between the second tube and the third tube. A first sealing element and a heat insulating material are disposed in the first interspace above the through-holes.

It is provided a power generation model based on a transcritical cycle with an increasing-pressure endothermic process using CO.sub.2-based mixture working fluids for an enhanced geothermal system, including a geothermal water circulation, a mixture working fluid circulation and a cooling water circulation. A coaxial pipe-in-pipe downhole heat exchanger is provided in the mixture working fluid circulation. Innovations are reflected in that an increasing-pressure endothermic process is achieved due to making use of gravity and hence increase a heat quantity absorbed in a cycle, thereby improving power generation quantity of the cycle; and a binary mixture working fluid composed of CO.sub.2 and an organic working fluid is adopted to realize a transcritical power cycle with an increasing-pressure endothermic process and a decreasing-temperature exothermic process, thereby effectively reducing irreversibility of a heat transfer between a working fluid and a heat source and improving power cycle efficiency.

An underground heat exchange type cooling and heating system includes an underground heat exchange device to allow heat to be exchanged between a first heat medium and a geothermal heat; a plurality of cooling and heating units which cools or heats an indoor space by means of a second heat medium; a plurality of heat pump units which allows heat to be exchanged between the first heat medium and the second heat medium; a first transfer line which transmits the first heat medium to the plurality of heat pump units and transmits the first heat medium having undergone heat exchange in the plurality of heat pump units to the underground heat exchange device; and a second transfer line which transmits the second heat medium to the plurality of cooling and heating units.

A method for obtaining useful energy from geothermal heat. A coaxial tube is provided which includes an inner and outer tube connected to together in an end section of the coaxial tube. The coaxial tube is introduced into a deep bore in the earth and a thermal medium liquid under standard conditions is introduced into the outer tube and flows in the direction of the end section of the coaxial tube. The thermal medium is heated while absorbing geothermal heat, passes through a phase transition in the region of the end section, passes over in gaseous form into the inner tube, and flows upward therein up to an upper end of the coaxial tube located at the Earth's surface. A flow generator for generating electric energy is operated using the flowing, gaseous thermal medium and the kinetic energy of the flowing gaseous thermal medium is converted to obtain usable energy.

A method for obtaining useful energy from geothermal heat. A coaxial tube is provided which includes an inner and outer tube connected to together in an end section of the coaxial tube. The coaxial tube is introduced into a deep bore in the earth and a thermal medium liquid under standard conditions is introduced into the outer tube and flows in the direction of the end section of the coaxial tube. The thermal medium is heated while absorbing geothermal heat, passes through a phase transition in the region of the end section, passes over in gaseous form into the inner tube, and flows upward therein up to an upper end of the coaxial tube located at the Earth's surface. A flow generator for generating electric energy is operated using the flowing, gaseous thermal medium and the kinetic energy of the flowing gaseous thermal medium is converted to obtain usable energy.

A heat exchange device for stabilizing the ambient temperature in large spaces is provided. The heat exchange device comprises an inner tube and an outer tube of rigid material. The outer tube is open at its upper part and closed at its lower part, with a diameter approximately sixty percent greater than the diameter of the inner tube and a length of more than ten meters. The inner tube is also open at its upper part and closed at its lower part, and the perimeter of its lower side has a series of holes. The inner tube is inserted into the outer tube and it has several clamps, which have at least three symmetrical legs located in the perpendicular plane of the axes of the tubes and ending in their respective wheels on free axes. In the upper part of the inner tube an air extractor device is located.