ENERGY STORAGE

• US 20150112751A1
• Filed: 03/19/2013
• Published: 04/23/2015
• Est. Priority Date: 03/30/2012
• Status: Active Grant

• Current Assignee: Sony Europe (Amsterdam) BV (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.), Sony Europe Limited (Sony Group Corp.)
• Inventors: Spooren, Jan, Rutherford, Christopher
• Granted Patent: US 10,192,184 B2
• Time in Patent Office: Days
• US Class Current: 705/7.25
• CPC Class Codes: G06Q 10/06315 Needs-based resource requirements planning or analysis
• CPC Class Codes: G06Q 50/06 Energy or water supply
• CPC Class Codes: H02J 2310/64 The condition being economic, e.g. tariff based load management
• CPC Class Codes: H02J 3/14 by switching loads on to, or off from, network, e.g. progressively balanced loading
• CPC Class Codes: H02J 3/32 using batteries with converting means
• CPC Class Codes: Y02B 70/3225 Demand response systems, e.g. load shedding, peak shaving
• CPC Class Codes: Y04S 20/222 Demand response systems, e.g. load shedding, peak shaving
• CPC Class Codes: Y04S 50/10 Energy trading, including energy flowing from end-user application to grid

Abstract

A method of controlling storage of electrical energy by charging and discharging an energy storage device in response to pricing data indicative of future prices of electrical energy over time and energy losses caused by charging and discharging the energy storage device comprises detecting alternating candidate charging and discharging occasions with respect to the pricing data by selecting a next occurrence of a locally minimum price in the pricing data as a candidate charging occasion or a next occurrence of a locally maximum price in the pricing data as a candidate discharging occasion; validating a candidate charging or discharging occasion if the price difference between that candidate charging or discharging occasion and another later price in the pricing data is at least sufficient to compensate for the energy losses caused by charging and discharging the energy storage device; and charging and discharging the energy storage device at the validated charging and discharging occasions, respectively.

Claims

1. A method of controlling storage of electrical energy by charging and discharging an energy storage device in response to pricing data indicative of future prices of electrical energy over time and energy losses caused by charging and discharging the energy storage device, the method comprising:

detecting alternating candidate charging and discharging occasions with respect to the pricing data by selecting a next occurrence of a locally minimum price in the pricing data as a candidate charging occasion or a next occurrence of a locally maximum price in the pricing data as a candidate discharging occasion;

validating a candidate charging or discharging occasion if the price difference between that candidate charging or discharging occasion and another later price in the pricing data is at least sufficient to compensate for the energy losses caused by charging and discharging the energy storage device; and

charging and discharging the energy storage device at the validated charging and discharging occasions, respectively.

2. A method according to claim 1, in which the step of validating a candidate charging or discharging occasion comprises detecting whether the pricing data relating to that candidate occasion represents the respective lowest or highest price before the later price which validates that candidate occasion, and if not, replacing the candidate charging or discharging occasion by the respective lowest or highest price before the later price which validates that candidate occasion.

3. A method according to claim 1, in which the validating step detects whether:

P_D>

P_C/Eff,

where P_D represents the price at the discharge occasion, P_C represents the price at the charging occasion, and Eff represents the efficiency of the charging and discharging of the energy storage device such that Eff is equal to the ratio of energy retrieved at discharging to energy input at charging.

4. A method according to claim 1, in which the pricing data used by the detecting and validating steps represents a time average of the pricing data over a predetermined time period.

5. A method according to claim 1, in which the validating step is operable to integrate the cost of electricity consumption against time over a charging cycle to detect the price associated with a charging occasion.

6. A method according to claim 1, in which the validating step is operable to apply a time-varying energy loss relating to a charged energy storage device in dependence upon an elapsed time since the last charging occasion.

7. A method according to claim 1, comprising the step of:

determining whether a first of the occasions should be a charging occasion or a discharging occasion in dependence upon a present charging state of the energy storage device.

8. A method according to claim 7, in which the determining step comprises comparing a measure of the present charging state with a threshold amount.

9. A method according to claim 8, comprising the step of:

varying the threshold in dependence upon the pricing data.

10. Computer software which, when executed by a computer, causes the computer to carry out the method of claim 1.

11. A storage medium which stores computer software according to claim 10.

12. An energy storage controller for controlling storage of electrical energy by charging and discharging an energy storage device, the controller being responsive to pricing data indicative of future prices of electrical energy over time and energy losses caused by charging and discharging the energy storage device, the controller comprising:

a detector configured to detect alternating candidate charging and discharging occasions with respect to the pricing data by selecting a next occurrence of a locally minimum price in the pricing data as a candidate charging occasion or a next occurrence of a locally maximum price in the pricing data as a candidate discharging occasion;

a validator configured to validate a candidate charging or discharging occasion if the price difference between that candidate charging or discharging occasion and another later price in the pricing data is at least sufficient to compensate for the energy losses caused by charging and discharging the energy storage device; and

a charge controller operable to charge and discharge the energy storage device at the validated charging and discharging occasions, respectively.

13. An energy storage apparatus comprising:

an energy storage device; and

an energy storage controller according to claim 12, for controlling energy storage by the energy storage device.

14. An apparatus according to claim 13, in which the energy storage device comprises one or more batteries.

15. An apparatus according to claim 14, comprising an inverter for producing an output voltage higher than the battery voltage.

16. An apparatus according to claim 13, in which the energy storage device comprises a movable mass having a motor for driving the movable mass and a generator for generating electrical power from motion of the movable mass.

17. An electricity consumption meter comprising apparatus according to claim 12.