Energy Storage and Recovery System

Abstract

An electric energy storage and recovery system is provided to store electric energy from a generator when it is not required for the electric power grid. The system employs a controller to switch a generator between operating as an electric motor in power storage mode and operating as a generator in a power generation mode. A weight engaged to a distal end of a cable may be wound upon a reel by the generator when operating as an electric motor. The weight, in an elevated position, will pull the cable from the reel to rotate the generator and produce electric power when operating in power generation mode.

What is claimed is: 
     
         1 . An electric energy storage and recovery system comprising:
 a generator, said generator operating to produce electric power upon communication of powered rotation thereto;   said generator operating as an electric motor upon communication of electrical power thereto;   a reel, said reel in a winding engagement with a cable having a weight thereon;   said reel rotationally engaged to said generator;   a controller, said controller in communication with an electric grid connected to an electric power source;   said controller switchable to an energy generation mode, wherein it connects said electric power from said generator to said electric grid;   said controller switchable to an energy storage mode, wherein it operates to communicate said electric power from said electric grid to said generator to cause said generator to operate as said electric motor;   said reel rotating to wind said cable thereon and to move said weight from a lowered position to an elevated position while said controller is in said energy storage mode; and   said reel rotating to unwind said cable thereon to communicate said powered rotation to said generator, with said controller in said energy generation mode, wherein electric power produced by said generator is communicated to said grid with said controller in said energy generation mode, and rotational energy to communicate said powered rotation to said generator is stored by movement of said weight from said lowered position to said elevated position, with said controller in said energy storage mode.   
     
     
         2 . The electric energy storage and recovery system of  claim 1  further comprising:
 said generator operatively engaged to a windmill positioned at an upper end of a support tower opposite a lower end thereof in a connection with a support surface; 
 said cable having said weight thereon positioned within an axial passage of said support tower; 
 said lowered position of said weight being at said lower end of said tower; and 
 said elevated position of said weight being at or adjacent said upper end of said support tower. 
 
     
     
         3 . The electric energy storage and recovery system of  claim 1  further comprising:
 said generator positioned at a top end of a ramp; 
 said weight in a rolling engagement upon said ramp; 
 said lowered position of said weight being at said lower end of said ramp; and 
 said elevated position of said weight being at or adjacent said top end of said ramp. 
 
     
     
         4 . The electric energy storage and recovery system of  claim 1  further comprising:
 a computer in electronic communication with said controller; 
 software running in electronic memory of said computer operating to the task of determining a current utility rate charged for said electric power, said current utility rate being a rate between a highest charged rate, and a lowest charged rate; 
 said controller operating to switch to said energy storage mode when said current utility rate is closer to said lower charged rate; and 
 said controller operating to switch to said energy generation mode, when said current utility rate is closer to said highest charged rate. 
 
     
     
         5 . The electric energy storage and recovery system of  claim 2  further comprising:
 a computer in electronic communication with said controller; 
 software running in electronic memory of said computer operating to the task of determining a current utility rate charged for said electric power, said current utility rate being a rate between a highest charged rate, and a lowest charged rate; 
 said controller operating to switch to said energy storage mode when said current utility rate is closer to said lower charged rate; and 
 said controller operating to switch to said energy generation mode, when said current utility rate is closer to said highest charged rate. 
 
     
     
         6 . The electric energy storage and recovery system of  claim 3  further comprising:
 a computer in electronic communication with said controller; 
 software running in electronic memory of said computer operating to the task of determining a current utility rate charged for said electric power, said current utility rate being a rate between a highest charged rate and a lowest charged rate; 
 said controller operating to switch to said energy storage mode when said current utility rate is closer to said lower charged rate; and 
 said controller operating to switch to said energy generation mode, when said current utility rate is closer to said highest charged rate. 
 
     
     
         7 . The electric energy storage and recovery system of  claim 2  further comprising:
 a computer in electronic communication with said controller; 
 software running in electronic memory of said computer operating to the task of determining a current power requirement of the power grid; and 
 said controller operating to switch to said energy storage mode when said current power requirement of said power grid, is sufficient without the communication of said electric power produced by said generator. 
 
     
     
         8 . The electric energy storage and recovery system of  claim 1  further comprising:
 said generator operatively engaged at the top end of a vertical passage formed in a building, said vertical passage extending to a lower end opposite said top end; 
 said cable having said weight thereon positioned within an axial passage of said vertical passage; 
 said lowered position of said weight being at said lower end of said vertical passage; and 
 said elevated position of said weight being at or adjacent said top end of said vertical passage.