Energy Storage Energy Storage ApplicationsApplications at AEP at AEP

Emeka Okafor

American Electric Power

Presentation to SouthWest Electric Distribution Exchange

May 7, 2009

Outline:Outline:

1. Challenges facing utilities

2. Energy storage to turn some of these challenges into opportunities

3. Energy storage deployment examples at AEP

4. AEP taking deployment of energy storage to the next level

Challenges to the Utility BusinessChallenges to the Utility Business

Customer-controlled renewable DG on AEP grid has grown from 1kW to 1MW in a decade. It is expected to exceed 1GW in the next decade.

Customer renewable DG is intermittent, often not available when needed and out of utility control.

Utilities need a buffer between customer-controlled DG and electric grid.

Increasing demand for improved service quality and reliability

PHEV load (grid impact)

Converting Challenges to OpportunitiesConverting Challenges to Opportunities

Energy Storage:

Buffers between unpredictable customer generation and grid

Decouples load from generation

And offers other benefits as well …

2006 2006 - - Battery in a Substation for Capital DeferralBattery in a Substation for Capital Deferral

Installed 1MW, 7.2 MWh of NAS battery on a feeder to defer building a new substation for three years

Daily Peak Shaving –summer

Three years of operation

Tyler Mountain Feeder12 kV bus

North Charleston Feeder

West Washington FeederVoltage Regulator

46kV/12kV Transformer

12/16/20 MVA

46 kV bus

Peak shaving (load leveling).Peak shaving (load leveling).

Increased Reliability with Dynamic IslandingIncreased Reliability with Dynamic Islanding(Backup Power) for new installations(Backup Power) for new installations

Three installations (2008): Churubusco, IN (2MW, 14.4MWh) Bluffton, OH (2MW, 14.4MWh) Milton, WV. (2MW, 14.4MWh)

Loss of power. Pick up island. Power electronics and communication. Return load to grid when fault is cleared.

• 2MW, 14.4 MWh in Bluffton, Ohio

• Two other identical sites in West Virginia and Indiana (2008)

• All with dynamic islanding

2008 Projects 2008 Projects – To Improve Service Reliability

2MW, 14.4 MWh in Milton, WV

2008 Projects 2008 Projects – To Improve Service Reliability

2MW, 14.4 MWh in Churubusco, IN

Load Following - with new battery installations.

PERCENTAGE OF CUSTOMER OUTAGES THAT MAY BE REDUCED WITH BACKUP POWER.

(AEP OHIO 2008)

0.00%

10.00%

20.00%

30.00%

40.00%

50.00%

60.00%

70.00%

80.00%

90.00%

100.00%

1 2 3 4 5 6 7 8 >8

Hours

Cu

sto

mer

s R

esto

red

Percentage of Customers restored within 7 hours is

95.34%

Percentage of Customers restored within 7 hours is

95.34%

7 hours of backup power will ensure that over 95 percent of AEP Ohio customers will not experience an outage.

Assumption: excludes traditional major events and momentary outages.

Benefit of Islanding – How many hours of Benefit of Islanding – How many hours of backup power is needed?backup power is needed?

East Busco Station Battery Islanding Zones.East Busco Station Battery Islanding Zones.

System Normal :System Normal :Grid connected. Battery disconnected.Grid connected. Battery disconnected.

Fault at F8; loss of grid power. All reclosers Fault at F8; loss of grid power. All reclosers and switches in the island open.and switches in the island open.

Battery picks up island based on last load information.Battery picks up island based on last load information.

Grid power restored.Grid power restored.

Battery disconnected. Load connected back to the grid.Battery disconnected. Load connected back to the grid.

Building on Success …Building on Success …

AEP is very pleased with the performance of its substation batteries …

But we need to get MORE out of energy storage:

• More value to our customers

• Better cost by leveraging the electric transportation

• Better fit into Smart Grid, the way of future utilities

Community Energy Storage (CES)Community Energy Storage (CES)

Uses New or Used PHEV batteries – Low Cost

Offers All Values of Substation Batteries when aggregated,

Offers Backup Power to customers

Buffers Customer Renewable Generation

Makes PHEV Charging Time an irrelevant issue

CES is a small distributed energy storage unit connected to the secondary of transformers serving a few houses or small commercial loads for:

Value Associated with Storage Locations on the Grid

120/240 V69 kV 4 to 34 kV 480 V138 kV345 kV765 kV

Storage Value

Devaluators: Limited Value to Customer High Security Risk Does not remove Grid Constraints

Devaluators: Aesthetics O&M?

CES(Community Energy Storage)

NAS(Substation Battery)

CentralGeneration

Load

Distribution circuits appear to offer most value for hosting storage

CES Key Functions CES Key Functions

Local Controls/Benefits:

1) Backup power for the local need of the few houses connected to it

2) Voltage correction

Grid Controls/Benefits:

3) Load Leveling based on substation and grid needs

4) Power Factor Correction

5) Ancillary services through further aggregation at the grid level

Utility Dispatch Center /SCADA CES Control Hub

Station

Power Lines Communication and Control Links

CES Units CES Units

Integration Platform

Advantages of Using PHEV BatteryAdvantages of Using PHEV Battery

1. Safe for public deployment

2. Low cost- Fierce global competition- US national priority- Option to use used PHEV batteries

3. Compact

4. Reliable

5. Efficient

6. Wide operating temperature

7. Easy recycling & lower environmental issues

Advantages of CES to Substation BatteryAdvantages of CES to Substation Battery

1. Higher electric service reliability to customers

2. Easier installation (a 240 V appliance)

3. Easier maintenance (lower required skills)

4. More likely to be a standardized commodity

5. Unit outage is less critical to the grid (smaller)

6. Lower resistive loss in wires (closer to customer)

7. A better fit into the Smart Grid programs

CES Key Specifications CES Key Specifications

Key Parameters Value

Power (active and reactive) 25 kVA

Energy 50 kWh

Voltage 120V / 240V

Round Trip AC Energy Efficiency

> 85%

Life > 3000 cycles, 15 years

Audible Noise < 48dBA (no fans or filters)

Size Comparable to a 25kVA transformer

Most common distribution transformer size in AEP is a 25kVA unit that serves 3-5 houses.

CES Cost ForecastCES Cost Forecast

PHEV, and its battery development, is a US National Priority as well as having extensive global competition

Pending the successful market penetration of PHEV, CES cost forecast over the next five years is:

$1000 /kW Commodity Pricing will keep this number low

or

$500 /kWh PHEV penetration will push this number down

Putting It Together on DistributionPutting It Together on Distribution

DistributionOperations

Utility Operations Customer Premise

Adapted from EPRI source image

PHEV

CustomerPortal or Meter

LG Electronics

Putting It All Together - The Virtual Power Plant

2015 and Beyond

Conclusions.Conclusions.

• Energy Storage will be essential to meet the needs of the future grid.

• AEP has shown success with the use of NAS substation battery.

• AEP sees greater value to using Community Energy Storage to meet these new demands.

Questions?

2015 and Beyond