System to enable geothermal field interaction with existing HVAC systems, method to enable geothermal field interaction with existing HVAC system

Abstract

A system for adapting an HVAC system in an existing building for utilizing geothermal energy is described. The system uses an incoming flux of geothermal energy, along with a plurality of heat exchange surfaces adapted to receive the incoming flux of geothermal energy. The system also includes an interface between the HVAC system and the heat exchange surfaces. The interface is adapted to transfer the geothermal energy to the system. A multiplier sub for a drill rig and several drilling assemblies are also described, along with a system to reduce vibration.

Description

PRIORITY[0001]This application claims the benefits of U.S. Utility application Ser. No. 12 / 645,741 filed on Dec. 23, 2009, presently pending, which in turn claimed priority to U.S. Provisional Application Nos. 61 / 270,851, filed on Jul. 14, 2009, presently expired, both applications hereby incorporated by reference.BACKGROUND OF THE INVENTION[0002]1. Field of the Invention[0003]This invention relates to a system and a method to enable widespread adoption of geothermal energy and more particularly this invention relates to a system and a method for facilitating energy transfer from a geothermal field to an existing HVAC system of a building with minimal retrofit, thereby enhancing or retro fitting existing conventional HVAC systems with minimal interference of daily activity within the building.[0004]2. Background of the Invention[0005]Geothermal energy is an alternative energy source existing under ground. The goal for geothermal energy use is to utilize the typical midrange constant...

AI Technical Summary

Benefits of technology

This patent describes a system and method for utilizing geothermal energy to supplement the energy needs of permanent structures on a city lot. The invention allows for the drilling of multiple wells in close proximity to each other, resulting in a larger geothermal field with a smaller footprint. The use of rotary drilling to backfill and minimize fractures in the well bores reduces environmental impact and allows for a tight packing of geothermal wells within smaller ground footprints. Furthermore, the invention also provides a method for repairing aberrations in the drill bore wall, such as lost circulation zones, using a reverse auger system.

Problems solved by technology

Washout of the well bore caliper, or an unnecessary increase in the diameter of the well bore, results in a loss of the loop's ability to transfer a considerable percentage of energy.

This results in a loss of thermal conductance from the earth to the loop at that point.

Environmental containment of the drill site with air rotary drilling is very challenging.

Fuel consumption of equipment utilizing this method is extremely high due to massive amounts of horse power spent producing huge amounts of air at extremely high pressures.

Other drawbacks to air rotary drilling include disruption of adjacent structures such as aquifers and nearby wells.

Mud rotary drilling is less disruptive to nearby geologic structures, but also less effective in penetrating dense structures even when expensive diamond bits (such as those featuring polycrystalline diamond compact (PDC) inserts) are used.

Also, mud rotary drilling stops working when large cavities develop or are encountered during drilling, inasmuch as mud pressure drops significantly in these scenarios.

A subsequent drop in the return mud volume through the annulus (i.e., the space between the drill string and the sides of the well bore) results in cuttings not being carried to the surface of the hole for evacuation.

This in turn can result in another zone flowing into the wellbore and a catastrophic loss of well control.

But, such systems usually cannot generate enough mud to overcome the aforementioned pressure and / or volume drop when large cavities are encountered in consolidated formations.

Three to four wells spaced 20 feet apartment usually can be accomplished in most rural back yards; however the much larger tonnage requirements of high rise buildings and commercial businesses make the possibility of installing geothermal well fields on sidewalks, alley ways, and parking lots a real challenge.

1. The geothermal well drilling industry has no method for assuring a consistent caliper for wells at any depth.

2. Deep well drilling results in massive amounts of water and drilling spoils (cuttings) generated during air rotary drilling. This raises environmental issues.

3. Lack of a method for competitively using mud rotary drilling in consolidated formations. Loss of mud circulation becomes particularly acute in deep drilling. State of the art mud rotary drilling methods are not effective after lost circulation zones are encountered; therefore casings must be set deep through the zone. This casing installation is neither cost effective nor easy to remove.

4. Deterioration of silica sand-based grout during air rotary drilling in deep consolidated formations. This leads to contamination of fresh water aquifers.

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