Energy Storage and Power Management System

• US 20120197452A1
• Filed: 01/27/2012
• Published: 08/02/2012
• Est. Priority Date: 02/02/2011
• Status: Active Grant

• Current Assignee: Arista Power, Inc.
• Original Assignee: Arista Power, Inc.
• Inventors: Matthews, Mark, Nayar, Hari
• Granted Patent: US 8,886,363 B2
• Time in Patent Office: Days
• US Class Current: 700/292
• 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
• 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/charger; and

a energy inverter and/or rectifier, wherein

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

said energy inverter and/or rectifier being also connected to said at least one onsite connected energy source,

said energy storage system inverter/charger 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 least one onsite connected source and/or said electric grid, and to

provide power to said power load and/or to said grid from said least one onsite connected energy source and/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/discharge energy and/or power from the energy storage system by performing at least one of the following steps:

(a) discharging at previously designated times and/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 renewable energy source 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 inverter/battery charger and/or

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

(1) combine said AC power with energy taken from the grid and/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 inverter/battery charger, 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 will be 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 will be 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 or to each said at least one onsite connected energy source and another sub-storage is connected to the grid power and/or wherein at least one said energy storage sub-system has its own inverter/battery charger and/or at least two said energy storage sub-systems share the same inverter/battery charger.

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

9. A power management system according to claim 1, wherein said renewable energy source comprises a solar renewable energy source and/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. 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/charger in a standby mode,

the method further 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 inverter/battery charger 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 inverter/battery charger 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. 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/charger is 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 inverter/battery charger 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. Method according to claim 14, wherein said method according to claim 14 comprises:

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 said predetermined threshold, putting said energy storage system inverter/charger 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. Computer program product comprising computer readable instructions stored on a computer readable medium for causing a computer to perform method steps, when said computer readable instructions are executed on a computer or a computerized power management system, comprising:

program code for determining a level of energy stored in an energy storage system,

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

program code for obtaining a time of day, to be determined, and

program code for putting the inverter charger into standby mode,

program code for charging the energy storage system at a previously determined duration and rate of charge, and

program code for evaluating whether said charging is completed,

program code for returning to said obtaining of time step,

program code for obtaining the day of the week, and

program code for determining if said obtained day of the week is Sunday or Saturday,

program code for resetting and putting the inverter into Standby mode, and

program code for float charging said energy storage system, and returning to said obtaining of the day of the week and said following steps, and

program code for monitoring real time demand, and

program code for obtaining said energy storage charge or discharge values, and

program code for communicating said energy storage charge or discharge values to power management system, and

program code for controlling release and/or charge from/into said energy storage, and

program code for determining end of charge and/or discharge of energy storage, and

program code of setting or determining demand charge or discharge set points, and

program code for communicating data regarding the power management system, and

Program code for logging diagnostic information regarding the power management system.