Multi-segment weight in wellbore energy storage and retrieval

Abstract

A system for storing and retrieving energy may include a cable and a multi-segment weight connected to the cable. The multi-segment weight may include a chain of weight segments. The chain of weight segments may be flexible so as to permit each weight segment to rotate with respect to each of its neighboring weight segments.

Description

CROSS-REFERENCE TO RELATED APPLICATION[0001]This application is based upon and claims priority to U.S. provisional patent application 61 / 319,701, entitled “USE OF DEPLETED, ABANDONED, OR OPERATIONAL WELLBORES FOR ENERGY STORAGE USING SUSPENDED MASS,” filed Mar. 31, 2010, attorney docket number 028080-0566.[0002]This application is also related to co-pending application Ser. No. ______ filed on the same day as this application and with the same named inventor, priority claim, and assignee, entitled “Spaced-Apart Cable Modules In Wellbore Energy Storage And Retrieval,” attorney docket no. 028080-0636.[0003]The entire content of both of these applications is incorporated herein by reference.BACKGROUND[0004]1. Technical Field[0005]This disclosure relates to wellbore systems that utilize a suspended weight to store and retrieve energy.[0006]2. Description of Related Art[0007]Electric storage is becoming more critical as electric grids increasingly use variable sources of electrical energ...

AI Technical Summary

Benefits of technology

[0011]A system for storing and retrieving energy may include a cable and a multi-segment weight connected to the cable. The multi-segment weight may include a chain of weight segments. The chain of weight segments may flexible so as to permit each weight segment to rotate with respect to each of its neighboring weight segments. In this way, the total weight suspended within the wellbore can be considerable, allowing for the storage of considerable quantities of energy, and at the same time curvature and non-straightness of wellbores will not impose limits on operation or efficiency. Also, by making the weight in a segmented fashion, considerable weight can be suspended in the wellbore while individual segments are sized for ease of manufacture, transportation and installation.

Problems solved by technology

The variable nature of these sources may force electric utilities to maintain backup fossil-fuel burning sources to provide power when the variable sources suddenly drop in energy output.

However, adapting these technologies to a large electric grid, such as one that supplies an entire city, can be challenging.

Batteries can be expensive and their production and disposal may have undesirable environmental impacts.

Capacitors may be used for power conditioning, but may not be affordable for storage of large quantities of energy, and may not retain stored energy for useful periods of time.

Unfortunately, wellbores are often not straight.

This can cause the weight to jam against the wall of the wellbore as it is raised and lowered.

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