System and method for managing the charging and discharging of an energy storage device

• US 9,299,107 B2
• Filed: 03/12/2014
• Issued: 03/29/2016
• Est. Priority Date: 03/13/2013
• Status: Active Grant

• Current Assignee: Convergent Energy + Power
• Original Assignee: Convergent Energy + Power
• Inventors: Streeter, Christopher M., Genova, Frank III, Rittershausen, Johannes
• Primary Examiner(s): Shrestha, Bijendra K
• Application Number:
  US14/206,712
• Publication Number:
  US 20140279361A1
• Time in Patent Office: 748 Days
• US Class Current: 1/1
• CPC Class Codes: G06Q 40/04 Trading; Exchange, e.g. stocks, commodities, derivatives or currency exchange
• CPC Class Codes: G06Q 50/06 Energy or water supply

Abstract

Techniques for managing the charging and/or discharging of an energy storage device are disclosed. The techniques include obtaining clearing price data points spanning a plurality of dates and for each date: generating a distribution of the clearing price data points corresponding to the date; determining a lower quantile price point of the distribution based on a capacity of the device and a charge rate of the device; and determining an upper quantile price point of the distribution based on the capacity and a discharge rate of the device. The techniques include selecting a first set of the lower quantile price points from the lower quantiles and a second set of the upper quantile price points from the upper quantiles. The techniques include determining a buy bid based on the first set and a sell bid based on the second set and selectively transmitting the buy bid and/or the sell bid.

Claims

1. A method for managing the charging and/or discharging of an energy storage device, the method comprising:

receiving, at a processing device, clearing price data from an energy market server associated with a wholesale energy market and in communication with the processing device and the energy storage device, the clearing price data including an accepted price of a fixed amount of energy for delivery at a particular time and at a particular location;

receiving, at the processing device, storage device parameters from the energy storage device in communication with the processing device, the storage device parameters including a charge rate of the energy storage device, a discharge rate of the energy storage device, a total capacity of the energy storage device, and a current capacity of the energy storage device;

obtaining, at the processing device, a plurality of clearing price data points from the received clearing price data that span a plurality of dates, each clearing price data point being indicative of a clearing price of a unit of energy on a certain date;

for each date represented in the plurality of clearing price data points;

generating, at the processing device, a distribution of the clearing price data points corresponding to the date;

determining, at the processing device, a lower quantile price point of the distribution based on the total capacity of the energy storage device and the charge rate of the energy storage device; and

determining, at the processing device, an upper quantile price point of the distribution based on the total capacity of the energy storage device and the discharge rate of the energy storage device;

selecting, at the processing device, a first set of the lower quantile price points from the determined lower quantiles;

selecting, at the processing device, a second set of the upper quantile price points from the determined upper quantiles;

determining, at the processing device, a buy bid indicating an offered price for a purchase of energy at a first prescribed time based on the first set;

determining, at the processing device, a sell bid indicating an offered price for a sale of energy at a second prescribed time based on the second set;

transmitting the buy bid to the energy market server when the current capacity of the energy storage device is less than a maximum threshold, wherein when the buy bid transmitted to the energy market server is accepted by the energy wholesale market, the energy market server transmitting a charge instruction to the energy storage device instructing the energy storage device to enter into a charge mode at the first prescribed time and charge the purchased energy for a prescribed charging period starting at the first prescribed time; and

transmitting the sell bid to the energy market server when the current capacity of the energy storage device is greater than a minimum threshold, wherein when the sell bid transmitted to the energy market server is accepted by the energy wholesale market, the energy market server transmitting a discharge instruction to the energy storage device instructing the energy storage device to enter into a discharge mode at the second prescribed time and discharge the sold energy for a prescribed discharging period starting at the second prescribed time.

2. The method of claim 1, wherein the energy wholesale market determines clearing prices for energy.

3. The method of claim 1, wherein each clearing price data point is a day-ahead clearing price indicating a day-ahead clearing price of energy on a corresponding date;

and the buy bid and sell bid are each day-ahead bids.

4. The method of claim 1, wherein each clearing price data point is a same-day clearing price indicating a same-day clearing price of energy on a corresponding date;

and the buy bid and sell bid are each same-day bids.

5. The method of claim 1, wherein the selecting the first set of lower quantile price points includes:

for each lower quantile price point;

determining a type of day to which the lower quantile price point corresponds;

grouping the lower quantile price points into a specific group based on the type of day,

wherein the first set is comprised of lower quantile price points corresponding to the same type of day.

6. The method of claim 5, wherein the buy bid is determined by averaging the lower quantile price points of the first set.

7. The method of claim 1, wherein selecting the second set of upper quantile price points includes:

for each upper quantile price point;

determining a type of day to which the upper quantile price point corresponds;

grouping the upper quantile price points into a specific group based on the type of day,

wherein the second set is comprised of upper quantile price points corresponding to the same type of day.

8. The method of claim 7, wherein the sell bid is determined by averaging the upper quantile price points of the second set.

9. The method of claim 1, wherein determining the lower quantile price point of a distribution includes determining a lower quantile index based on the charge rate of the energy storage device, the total capacity of the energy storage device, and an amount of time divisions in a day, each time division representing an equal period during the day when energy is provided to a purchaser of the energy.

10. The method of claim 9, wherein the lower quantile index, Q_LOW, is determined according to:

11. The method of claim 1, wherein determining the upper quantile price point of a distribution includes determining an upper quantile index based on the discharge rate of the energy storage device, the total capacity of the energy storage device, and an amount of time divisions in a day, each time division representing an equal period during the day when energy is sold.

12. The method of claim 11, wherein the upper index value, Q_HIGH, is determined according to:

13. An energy market server for managing the charging and/or discharging of an energy storage device, the server comprising:

a network interface device;

a storage device; and

a processing device configured to;

receive clearing price data from the energy market server associated with a wholesale energy market and in communication with the processing device and the energy storage device, the clearing price data including an accepted price of a fixed amount of energy for delivery at a particular time and at a particular location;

receive energy storage device parameters from the energy storage device in communication with the processing device, the energy storage device parameters including a charge rate of the energy storage device, a discharge rate of the energy storage device, a total capacity of the energy storage device, and a current capacity of the energy storage device;

obtain a plurality of clearing price data points from the received clearing price data that span a plurality of dates, each clearing price data point being indicative of a clearing price of a unit of energy on a certain date;

for each date represented in the plurality of clearing price data points;

generate distribution of the clearing price data points corresponding to the date;

determine a lower quantile price point of the distribution based on the total capacity of the energy storage device and the charge rate of the energy storage device; and

determine an upper quantile price point of the distribution based on the total capacity of the energy storage device and the discharge rate of the energy storage device;

select a first set of the lower quantile price points from the determined lower quantiles;

select a second set of the upper quantile price points from the determined upper quantiles;

determine a buy bid indicating an offered price for a purchase of energy at a first prescribed time based on the first set;

determine a sell bid indicating an offered price for a sale of energy at a second prescribed time based on the second set;

transmit the buy bid to the energy market server when the current capacity of the energy storage device is less than a maximum threshold, wherein when the buy bid transmitted to the energy market server is accepted by the energy wholesale market, the energy market server transmitting a charge instruction to the energy storage device instructing the energy storage device to enter into a charge mode at the first prescribed time and charge the purchased energy for a prescribed charging period starting at the first prescribed time; and

transmit the sell bid to the energy market server when the current capacity of the energy storage device is greater than a minimum threshold, wherein when the sell bid transmitted to the energy market server is accepted by the energy wholesale market, the energy market server transmitting a discharge instruction to the energy storage device instructing the energy storage device to enter into a discharge mode at the second prescribed time and discharge the sold energy for a prescribed discharging period starting at the second prescribed time.

14. The server of claim 13, wherein the energy wholesale market determines clearing prices for energy.

15. The server of claim 13, wherein each clearing price data point is a day-ahead clearing price indicating a day-ahead clearing price of energy on a corresponding date;

and the buy bid and sell bid are each day-ahead bids.

16. The server of claim 13, wherein each clearing price data point is a same-day clearing price indicating a same-day clearing price of energy on a corresponding date;

and the buy bid and sell bid are each same-day bids.

17. The server of claim 13, wherein the processing device selects the first set of lower quantile price points by:

for each lower quantile price point;

determining a type of day to which the lower quantile price point corresponds; and

grouping the lower quantile price points into a specific group based on the type of day,

wherein the first set is comprised of lower quantile price points corresponding to the same type of day.

18. The server of claim 17, wherein the buy bid is determined by averaging the lower quantile price points of the first set.

19. The server of claim 13, wherein the processing device selects the second set of upper quantile price points by:

for each upper quantile price point;

determining a type of day to which the upper quantile price point corresponds; and

grouping the upper quantile price points into a specific group based on the type of day,

wherein the second set is comprised of upper quantile price points corresponding to the same type of day.

20. The server of claim 19, wherein the sell bid is determined by averaging the upper quantile price points of the second set.

21. The server of claim 13, wherein the processing device determines the lower quantile price point of a distribution by determining a lower quantile index based on the charge rate of the energy storage device, the total capacity of the energy storage device, and an amount of time divisions in a day, each time division representing an equal period during the day when energy is provided to a purchaser of the energy.

22. The server of claim 21, wherein the lower quantile index, Q_LOW, is determined according to:

23. The server of claim 13, wherein the processing device determines the upper quantile price point of a distribution by determining an upper quantile index based on the discharge rate of the energy storage device, the total capacity of the energy storage device, and an amount of time divisions in a day, each time division representing an equal period during the day when energy is sold.

24. The server of claim 23, wherein the upper index value, Q_HIGH, is determined according to: