Energy storage and power management system

• US 8,886,363 B2
• Filed: 01/27/2012
• Issued: 11/11/2014
• Est. Priority Date: 02/02/2011
• Status: Expired due to Fees

• Current Assignee: Arista Power, Inc.
• Original Assignee: Arista Power, Inc.
• Inventors: Matthews, Mark, Nayar, Hari
• Primary Examiner(s): PATEL, RAMESH B
• Application Number:
  US13/359,643
• Publication Number:
  US 20120197452A1
• Time in Patent Office: 1,019 Days
• Field of Search: 700/22, 700/286, 700291-293, 700/295, 700/297
• US Class Current: 700/295
• CPC Class Codes: H02J 2300/10 The dispersed energy generation being of fossil origin, e.g. diesel generators
• CPC Class Codes: H02J 2300/24 of photovoltaic origin
• CPC Class Codes: H02J 2300/28 The renewable source being wind energy wind motors F03D
• CPC Class Codes: H02J 3/008 involving trading of energy or energy transmission rights
• CPC Class Codes: H02J 3/32 using batteries with converting means
• CPC Class Codes: H02J 3/381 Dispersed generators
• CPC Class Codes: Y02E 10/56 Power conversion systems, e.g. maximum power point trackers
• CPC Class Codes: Y02E 10/76 Power conversion electric or electronic aspects
• CPC Class Codes: Y02E 70/30 Systems combining energy storage with energy generation of non-fossil origin
• CPC Class Codes: Y02P 80/10 Efficient use of energy, e.g. using compressed air or pressurized fluid as energy carrier
• CPC Class Codes: Y04S 50/10 Energy trading, including energy flowing from end-user application to grid

Abstract

A system to manage the storage of energy to, and the release of energy from, an energy storage system with such energy being generated from one or more renewable sources of energy, traditional sources of energy or the electric grid, or a combination of any or all of these sources, resulting in a reduction of the power demand from the electric grid of a user of the system and/or of the high consumption charges during peak usage times of a user of the system.

Claims

1. A power management system for reducing peaks of power demand from an electric grid by a power load in a power supply system having an energy storage system and at least one onsite connected energy source;

comprising;

a circuit breaker;

an energy storage system inverter operative to perform at least one of electrical inversion and charging; and

an energy inverter operative to perform at least one of electrical inversion and rectifying, wherein

said circuit breaker is connected to said electric grid and at least one of said energy inverter, said energy storage system inverter and said power load,

said energy inverter being also connected to said at least one onsite connected energy source,

said energy storage system inverter being connected to said at least one onsite connected energy source and to said energy storage system and via said circuit breaker to the power load,

wherein said system is configured to

charge the energy storage system with power from said at least one onsite connected source and/or said electric grid, and to

provide power to said power load or to said grid from said at least one onsite connected energy source or said energy storage system,

wherein said system is configured to store energy in the energy storage system and to determine the amount of energy to be stored by performing at least one of the following steps;

(a) charging the energy storage system at predetermined times;

(b) monitoring the power load taken from the electric grid and, when such power load is detected to fall below a predetermined level, charging the energy storage system;

(c) monitoring the power load taken from the electric grid and, when such power load is below the appropriate level as determined by the power management system, charging the energy storage system; and

(d) monitoring the remaining capacity level of the energy storage system and, when the remaining capacity of the energy storage system drops below a predetermined level or an appropriate level as determined by the power management system, charging the energy storage system.

2. A power management system according to claim 1, wherein said system is configured to release energy or power from the energy storage system by performing at least one of the following steps:

(a) discharging at previously designated times or durations;

(b) monitoring the current power load taken from the electric grid, and discharging, if the current power load taken from the electric grid is greater than or equal to predetermined threshold levels; and

(c) monitoring the current power load taken from the electric grid, and discharging, if the current power load taken from the electric grid is greater than or equal to the amount determined by the power management system to be a threshold point for reducing the power load taken from the electric grid.

3. A power management system according to claim 1, wherein said system is configured to determine the amount of energy to be discharged from the energy storage system at the correct power rate by performing at least one of the following steps:

(a) discharging at previously designated times amounts of energy at predetermined power rates;

(b) discharging an amount of energy calculated by monitoring the current power load taken from the electric grid and discharging only such amounts of energy stored in the energy storage system as would be necessary to lower the power load taken from the electric grid to an amount that is a little less than or equal to previously designated levels; and

(c) discharging an amount of energy calculated by monitoring the end current power load taken from the electric grid and discharging only such amounts of energy stored in the energy storage system as would be necessary to lower the power load taken from the electric grid to an amount that is a little less than or equal to the appropriate amount of power load to be taken from the electric grid as determined by the power management system.

4. A power management system according to claim 1, wherein the energy source system is configured to generate DC power, the power management system being configured to

(a) use the DC power to charge the energy storage system via the energy storage system inverter and/or

(b) invert the DC power to AC power by the energy inverter and to perform at least one of the following steps:

(1) combine said AC power with energy taken from the grid or energy from the energy storage system to partially or fully fulfill the requirement of power load after passing through the circuit breaker,

(2) store said AC power in the energy storage system, after passing through the circuit breaker and after being converted to DC power by the energy storage system inverter, and

(3) supply said AC power to the grid through a bidirectional meter or other manner after passing it through the circuit breaker.

5. A power management system according to claim 1, wherein said power management system is configured to distribute the energy generated by said at least one onsite connected energy source in accordance with the following hierarchy:

(a) first, energy generated by the at least one onsite connected energy source is used to supplement or replace grid power to meet the current power loads;

(b) second, if the energy generated by said at least one onsite connected energy source exceeds the current power load, any excess power generated by said at least one onsite connected energy source is used to charge the energy storage system; and

(c) third, if the energy generated by said at least one onsite connected energy source exceeds the current power load and the energy storage system has no additional capacity to store additional energy at that time, the energy is supplied to the grid through a bidirectional meter.

6. A power management system according to claim 1, wherein said power management system is configured to use grid power to partially or fully fulfill the requirement of power load after passing through the circuit breaker.

7. A power management system according to claim 1, wherein said energy storage system comprises one or more distinct energy sub-storage systems, that are connected to the system at the same physical location or wherein one energy sub-storage system is connected to at least one of said at least one onsite connected energy source and another sub-storage is connected to the grid power or wherein at least one said energy storage sub-system has its own energy storage system inverter or at least two said energy storage sub-systems share the same energy storage system inverter.

8. A power management system according to claim 1, wherein said energy storage system inverter and said energy inverter are integrated into a single device, or wherein said circuit breaker, said energy storage system inverter and said energy inverter are integrated in a single device.

9. A power management system according to claim 1, wherein said energy source comprises a solar renewable energy source or a wind renewable energy source.

10. A power management system according to claim 1, wherein said energy storage system comprises one of a battery system and capacitors.

11. A power management system according to claim 1, wherein said charging the energy storage system comprises charging the energy storage system with one of:

predetermined amounts of energy,

such amounts of energy necessary to charge the energy storage system to a predetermined capacity level between 80% to 100% full, and

such amount of energy necessary to charge the energy storage system to an appropriate level as determined by the power management system.

12. A power management system according to claim 1, wherein each said monitoring is performed in or close to real-time.

13. A power management system according to claim 1, wherein said power management system is connected to said electric grid, to said at least one onsite connected energy source, to said energy storage system and to said power load.

14. A method for reducing peaks of power demand on an electric grid or on the utility grid, by a power management system comprising an energy storage system inverter in a standby mode, the method comprising:

determining a level of energy stored in an energy storage system,

determining whether or not said energy storage system is sufficiently charged with energy in order to be discharged,

if the energy storage system is not sufficiently charged, obtaining a time of day, to be determined, and

if said obtained time of day is not within the predetermined time range in which the energy storage system inverter is directed to charge the energy storage system, putting the inverter charger into standby mode,

if said obtained time of day is determined to be within the range in which the energy storage system inverter is directed to charge the energy storage system, charging the energy storage system at a previously determined duration and rate of charge, and after said charging has been concluded, evaluating whether said charging is completed,

if it is determined that said charging of the energy storage system is not complete, returning to said obtaining of time step,

if it is determined that the charging operation has been completed, obtaining the day of the week, and

determining if said obtained day of the week is Sunday or Saturday, if said obtained day of the week is not Sunday or Saturday, reset and put inverter into Standby mode, and

if said obtained day of the week is Sunday or Saturday, float charging said energy storage system, and returning to said obtaining of the day of the week and said following steps.

15. The method according to claim 14, wherein

if it has been determined that the energy storage device is sufficiently charged, obtaining the time of day,

determining whether said obtained time of day is within a range of times of day to discharge energy from the energy storage system,

if it is determined that said obtained time of day is not within said range of times in which the energy storage system is directed to discharge energy, putting said energy storage system inverter into standby mode, and, returning to said obtaining the time and the following steps,

if it is determined that said obtained time of day is within said range of times in which the energy storage system is directed to discharge energy, discharging energy from the energy storage system by the energy storage system inverter based on discharge parameters, after the discharge has been concluded based on said discharge parameters, determining whether the discharge is complete,

if the discharge is determined to be complete, returning to said obtaining of said time of day and said following steps,

if said discharge is determined not to be complete repeating said discharging, until the discharge is determined to be complete.

16. The method according to claim 14, wherein:

if it has been determined that the energy storage device is sufficiently charged, determine the power load taken from the electric grid,

determining if the power load taken from the electric grid is not at or in excess of a predetermined threshold at which the energy storage system is directed to discharge energy,

if said power load taken from the electric grid is not at or in excess of said predetermined threshold, putting said energy storage system inverter into standby mode,

if said power load taken from the electric grid is at or in excess of said predetermined threshold, discharge energy from the energy storage system according to determined discharge parameters,

after the discharge has been concluded, return to said determining step whether the energy storage system is still sufficiently charged with energy.

17. A computer program product comprising:

a non-transitory, computer-readable storage medium; and

computer-readable program code embodied in the storage medium, wherein the computer-readable program code is configured to perform the steps of claim 14.