DE102011113094A1 - Geothermal power plant has closed system provided in interior of earth, in which water or steam, such as liquid or evaporable substance, is directed, where closed system is provided as pipes or tube-like system - Google Patents

Abstract

The geothermal power plant has a closed system provided in interior of earth, in which water or steam, such as liquid or evaporable substance, is directed. The closed system is provided as pipes or tube-like system. Main borehole is divided into one or multiple small boreholes, where an operating substance, such liquid or vapor, is heated and returned to the top. The main borehole is provided without or with one or multiple inclined holes in a magma chamber by using a drilling system. The geothermal power plant is located on sea surface, on earth surface or below earth surface. An independent claim is included for a pump storage plant.

Description

Other Information

1. Technical field: Geothermal energy production

2. State of the art:

Geothermal power plants operate so far i. W. according to two principles: First, existing hot steam (sometimes hot water) prospected and then promoted. On the other hand, water is injected into hot rocks. This water creates microcracks in the rock. It heats up in the rock and enters the earth's surface in other holes. There it is then used partly directly, partly indirectly (eg but not only with the so-called "Kalina process"). Microcracking side effects sometimes cause small earthquakes in areas of stress. In addition, the corresponding holes are very expensive.

To solve this problem (another patent), the "chisel-less drilling system" was developed, with which one comes very fast (1 m / minute, for 10 km 1-2 weeks) with very large diameters (2 meters) in very large depths (eg 10-14 km).

Water flows down the hole, heats up in (!) The hole and flows up again as superheated steam. It is a closed (!) System. The problems of conventional drilling thus do not occur (!).

For larger outputs (eg 100 MW per hole), correspondingly large areas are required. This is due to the fact that the rock usually can not deliver the heat to the main well as fast as it is taken. For 2 MW in 350 ° C hot granite z. B. 25000 square meters area required (the bottom 4 km of the main bore).

There are thus in the lower part of the main bore, z. B. km 8-10 about 200-300 smaller holes z. B. obliquely into the rock with z. B. 0.5 m diameter and 4-6 km in length. Each of these holes then generates 0.5 MW in the example above. 100 MW can thus be easily generated with 200-300 such small holes. If the holes are drilled in stable rock (eg quartzite, sandstone, limestone, granite), the angle in the upper part of the oblique holes is no problem.

A giant main bore, instead of two meters in diameter z. B. 20 m diameter, possibly with slots on the sides to achieve the large area is uneconomical at 10-14 km (cost of transport of the material up). "Only" deflected holes directly from the surface, ie 200-300 holes, each producing 0.5 MW, are also uneconomical (cost of the steel for the distance of 0-10 km depth). A large main hole up to 10 km, z. B. with 2 m diameter and 200-300 oblique holes, is very economical. The principle of the oblique holes, which depart from a main well, has been known in the oil industry for many years. Because of this, it is not a new invention in "geology in general". If someone tricked into thinking that it was a new invention, it is thus filed for patent.

For power plants, it is of course new, since there are such geothermal power plants, in particular the type: main well plus many sidetracks, usually with a closed system, not yet (invention height).

Derived from: Geothermal run-of-river power plants.

In conventional run-of-river power plants, for example in the Isar, a river is dammed slightly, flows through a turbine and generates electricity. The low drop height requires a low yield.

With the "chiselless drilling system" of another patent, you can quickly drill very deep, for example, in 7-10 km. There, a turbine can be installed. The water used in the turbine heats up in other pipes in the rock and "voluntarily" rises as steam. It can then either be condensed, for example for home heating, or escape to the atmosphere. If such a geothermal running power z. B. installed on the Lower Rhine or the Elbe, very large amounts of energy can be achieved (industrial applicability). The same applies to the supply of large cities in the area of the large lakes of the USA (Chicago, Toronto, Montreal) and / or the large rivers there (Missouri and others).

In the field of drilling technology this is obvious to me. This is completely new in the field of power plant technology.

Associated with this: cutting long narrow caverns, for example from 7-8 km depth (ie 1 km altitude) and z. B. 10 m width on the type of "unscrupulous drilling system": Thus, according to the above geothermal running power plant, surplus quantities are stored in wind power. This also applies mutatis mutandis to caverns that reach almost or to the earth's surface. The caverns are then either pumped empty by excess flow or, in the above sense, by geothermal emptying of greater heat below or as a combination solution.

Caverns themselves and pumped storage power plants are not new, see one of the Olympic halls in Lillehammer / Norway (blown up into the rock) or the Walchensee / Kochelsee power plant. What is new is that they have an extremely high yield due to the great depth. Since such high-yield pumped storage plants do not yet exist and since these can optionally be emptied geothermally and / or by pumps, they are part of the patent specification.

In the case of salt water (and similar liquids, eg brackish water), pumped storage plants directly at wind farms in the North Sea, the emptying is usually done by pumping; in geothermal cases usually by scraping / dissolving the salt at appropriate times.

Since the problem of storing large amounts of wind power has not yet been solved, it is clearly not obvious for experts in the energy industry.

My own understanding: I am a geologist.

3. Underlying problem:

Cost-effective to achieve the large area for steam generation at great depths for energy production, either directly by the hot steam or by run-of-river power plants (turbines at very great depths), the water via pumps (pumped storage plants) and / or via geothermal heat (as steam) move up.

4. The invention for protection is sought:

Geothermal power plants that use the principle: One or more main wells, in which one or more smaller holes open, the steam flows completely or predominantly in a closed system (different from Dublettensystemen or for conveying steam from corresponding deposits (technical term in the Geothermal: Reservoirs)). In addition: Geothermal run-of-river power plants in the illustrated sense and pumped storage power plants in / to very large depths, which are optional, but not mandatory, geothermal energy for emptying caverns or cavern-like cavities (eg long slots), pipes, etc. use.

5. Industrial Applicability:

Cost-effective geothermal power with z. 3 Ct / kWh costs in the phase of repayment (4-7 years) and then a maintenance reserve of (example for summer 2011) only approx. B. 0.9 Ct / kWh (plus royalties, insurance, etc.) Geothermal electricity is so much cheaper than coal electricity and probably cheaper than nuclear power.

6. Advantageous effects:

• See (5)

7th execution:

Using the same technique as the "chisel-less drilling system" - just a bit miniaturized - drill the "small" holes (about 0.5 m in diameter 4-6 km in length): partly self-drilling, partly by licensees.

As well as in caverns: cutting blocks, for example but not only, of 2 × 2 × 10 m dimensions and transporting the blocks upwards.

Claims (4)

Geothermal power plants, characterized in that water or steam (including liquids, vaporizable substances including solids) in a closed or predominantly closed system into the Earth's interior technically conducted (ie usually in pipes and pipe-like systems, but not in rivers) to flow , to heat up there and usually heated as steam (including steam / condensate, liquid), reach the usually located on the surface of the earth power plant or a technical system and indeed without (!) The pipe / pipe system inside the earth in regular operation to leave (in contrast to previous systems) where in addition in the lower part of one (Regefall) or more (not appropriate) main wells one to many smaller holes (sidetracks) branch off, in which the operating substance (liquid, steam, etc.) heats up and back flows upwards (eg because the hole is divided by a wall) , The term "on-surface power plant" also refers to other suitable "surfaces" on which the power plant (s) are located, e.g. A sea surface, above the earth's surface (eg on stilts), below the earth's surface at a suitable depth, etc. The claims relate only to geothermal power plants in which the suitable operating substance is completely or predominantly contained in closed systems (e.g. Pipes) flows and in which the operating substance is introduced technically (eg in pipes) into the Earth's interior, wherein the substance as a rule leaves the pipes not (!) (Difference to the promotion of a steam storage and to Dublettensystemen). Duplicate systems in which water leaves the holes and heats up in the rock, with the aim of reaching the earth's surface again in another hole, are not covered by the claims. The word "predominantly" closed systems serves to avoid legal trickery. At present, only one application in closed systems seems sensible. But someone could come up with the idea of z. For example, to generate 100 MW of a geothermal power plant 99 MW according to the patent and 1 MW with an open system. This is of course included in the patent. The claims also relate to geothermal power plants where z. B. the main bore without or with one or more oblique holes (sidetracks) in a magma chamber depends, z. Example, by using the "chisel-free drilling system" another patent and corresponding high-performance ceramics or steels or composite materials, which have a high melting point and conduct heat well. This also applies to solutions in which the main bore then contains a steam generator in the lower area. For magma chambers that are always filled, z. For example, in the area of mid-ocean ridges (eg the Krafla on Iceland or some volcanoes on Hawaii), or permanently active volcanoes, this can be economically viable. The claims also relate to systems in which a substance (usually a liquid or a low-melting metal) is introduced into the skin bore and / or sidetracks ("the small oblique holes") with the aim of incorporating this into the skin Press underground to create microcracks, but without (!) Striving to get the heated substance (liquid / metal) back to the earth's surface. These microcracks can intentionally (!) Technically alter (sometimes degrade) the rock strength, so that tensions intentionally (!) Dissolve in the rock as small earthquakes. These phenomena were previously considered to be very disturbing in geothermal energy (Basel, Landau). However, you can, for. For example, insurance may be used commercially in areas where there are tensions (eg, Tokyo, Haiti) that are deliberately triggered so early and so controlled that a large earthquake can be found in numerous small, harmless ones Earthquake discharges ("first steps to earthquake avoidance"). The industrial applicability is then the saved costs of destroyed cities, be it by the earthquake itself or, where it happens, the subsequent tsunami. With the "chisel-less drilling system" of another patent specification, the corresponding depths can be achieved in geologically cold areas (eg Japan). Geothermal run power plants Power plants in which, but not only, fresh water and / or other suitable liquids flow down to great depth, generate electricity in a turbine at very great depth, and usually return up without storage, usually as steam in pipes. For large rivers and large lakes, this makes economic sense. Instead of the tubes, although this seems very inappropriate, the water / liquid can also flow directly into stable rock and heat up, for example, through pipes drilled in the rock by the "unshifted drilling system" that are not and / or only partially to be cased or, for example but not only, to be cased only during drilling (complete or partial removal of the steel / wall depending on stability), for example to save steel. This is because of inexpedient, because all the problems of classic geothermal energy problems occur again and / or the vapor can escape flat on the earth's surface. The distinguishing criterion for classic geothermal energy is the turbine installed at a great depth. Combination solutions of the type: Benefits of superheated steam at the top of a power plant and / or effluent water through a turbine below are also covered by the claims. Pumped storage plants at very great depth with a turbine at very great depth. These, like geothermal run-of-river power stations, can optionally be emptied by heat or pumped or combined. Distinguishing criterion for classical pumped storage plants is the very large depth of the turbine and / or the optional geothermal emptying capability. The word "turbine" applies mutatis mutandis to other facilities for power generation, for example, "many turbines", one or more reciprocating engines (for example, a large marine engine, new or used, operated by water / steam, etc.).