Large scale grid energy storage based on aluminum technology

a technology of aluminum technology and large-scale grid, applied in the direction of manufacturing tools, separation processes, electric circuits, etc., to achieve the effect of minimizing electricity consumption

Inactive Publication Date: 2013-11-07
XIAO XIN
View PDF8 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Benefits of technology

The patent text explains that energy represents a large part of the costs associated with primary aluminum production. As a result, producers have always been interested in minimizing electricity consumption. The text estimates that 0.7 quadrillion BTUs / year are consumed in maintaining grid balance while none of that energy is delivered to the end user. This approach has multiple benefits and improved economics for both the industrial and utility sectors.

Problems solved by technology

However, it is only half of a battery because the reaction is not reversible for electricity generation.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Large scale grid energy storage based on aluminum technology
  • Large scale grid energy storage based on aluminum technology
  • Large scale grid energy storage based on aluminum technology

Examples

Experimental program
Comparison scheme
Effect test

example 1

[0025]Example of an erratic electricity load at 5-minute intervals in 7 days is shown in FIG. 1. Wind power varies even more. Data was taken from the BPA Balancing Authority Load & Total Wind Generation during Apr. 5-11, 2012 for illustration purposes. Aluminum production consumes about 5-6% grid power globally (4% in the US). By intermittent aluminum production, excess electricity can be stored as chemical energy in aluminum metal production. During high electricity demand from the grid, aluminum smelters can be set at idle, effectively increasing baseload by the amount that the aluminum smelter plant would consume. The aluminum smelter plant can work as a “passive battery” for energy storage and can return its load to the grid when it is needed. Both storage and load release can be instantaneous, and round trip efficiency can be just slightly lower than 100% only for heat loss during the idling of an aluminum smelter. Double capacity of an aluminum smelter plant will be needed for...

example 2

[0026]FIG. 2 shows the new design of an aluminum smelter cell with vacuum thermal insulation at the cradle and top cover. The current aluminum smelter cell does not operate intermittently as required in Example 1 because the molten metal and electrolyte in the smelter would solidify after prolonged idling. By changing the design to FIG. 2, heat transfer by conduction, convection and radiation are reduced to minimum; therefore, the smelter cell can be left idling anytime as needed. This capability is important to enable its electricity load back to the grid.

example 3

[0027]FIG. 3 shows another design of an aluminum smelter cell with external heating and insulation to maintain the internal temperature of the smelter cell. Heat only transfers from high temperature to low temperature. When external heaters are set to match the skin temperature of cradle and top cover, temperature gradient becomes zero and heat transfer essentially stops. The smelter cell itself is therefore adiabatic.

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

PropertyMeasurementUnit
operating temperatureaaaaaaaaaa
melting pointaaaaaaaaaa
melting pointaaaaaaaaaa
Login to View More

Abstract

Grid energy storage is very challenging due to its large scale, required quick response, versatility, round trip efficiency, and new system infrastructure. However, the benefit is also huge because it would enable utilisation of intermittent renewable energy, leverage load, and allow energy management in hours / diurnal to seconds / minutes. A new invention is described to store up to 4-6% the entire grid energy by aluminum production, while returning its baseload back to the grid by idling aluminum smelter cells. The round trip efficiency will be close to 100%; switching between storage and load release can be instantaneous.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS[0001]Not applicable.FIELD OF THE INVENTION[0002]This disclosed technology relates to a grid-connected energy storage system that can make more efficient use of intermittent renewal energy sources, as well as a method of balancing the load of the power grid.BACKGROUND[0003]The amount of power available from the grid is usually determined by the power generation capacity connected to the grid, which should at least meet peak demand. On the other hand, during off-peak hours, the energy demand may be very much smaller. Therefore, excess energy is available for storage. About 20% of the annual kilowatt hours (KWH) consumed in the US comes from peaking power plants, which costs substantially higher. Just store 3% electricity, and it would reduce 30% of the cost to generate peak electricity demand.[0004]Electrical demand varies considerably and often rapidly with the time of day, day of week, and season. Baseload generating plants, e.g. coal fired an...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & AuthorityApplications(United States)
IPC IPC(8): C25C3/06C25C3/20C25C3/08
CPCC25C3/085
InventorXIAO, XIN
OwnerXIAO XIN