Pedro C. Elizondo – ABB Inc – March 2014
Battery Energy Storage Systems (BESS)
For peak shaving and demand management
© ABB Inc.
March 21, 2014 | Slide 1
What is Battery Energy Storage System (BESS)?
From DC to 3 phase Voltage
Network
Power
Converter rectifies the AC
energy into DC to store in the
batteries and then invert the DC
energy into AC energy.
Battery Energy Storage System Components
Energy Flow
Charging
Batteries
Batteries
Inverters
(bidirection
al) AC to
DC and DC
to AC
Network
Connection
Point
Step up or Isolation
Transformer
+
MV or LV SWGR
Discharging
Batteries
LOAD
Demand Response challenge
Demand Profile is variable
kW
KW max
1/1/2012
2/1/2012
Peak demand time
5/1/2012
KW avg
6/1/2012
7/1/2012
8/1/2012
9/1/2012
10/1/2012
11/1/2012
12/1/2012
1
2
3
4
5
6
7
8
9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Ideal situation=> kW avg / kW max = 1
© ABB Inc
March 21, 2014 | Slide 5
3/1/2012
4/1/2012
Sum of Hour 1
Sum of Hour 2
Sum of Hour 3
Sum of Hour 4
Sum of Hour 5
Sum of Hour 6
Sum of Hour 7
Sum of Hour 8
Sum of Hour 9
Sum of Hour 10
Sum of Hour 11
Sum of Hour 12
Sum of Hour 13
Sum of Hour 14
Sum of Hour 15
Sum of Hour 16
Sum of Hour 17
Sum of Hour 18
Sum of Hour 19
Sum of Hour 20
Sum of Hour 21
Sum of Hour 22
Sum of Hour 23
Sum of Hour 24
0.00020
0.00018
0.00016
0.00014
0.00012
0.00010
0.00008
0.00006
0.00004
0.00002
0.00000
Efficient Use of Electricity
Optimize the assets
The current design practice is to build and support a power network
designed the meet the highest peak load of the year. By doing this a
large portion of the system sits idle most of the year. Smart Grid aim is
to reduce this gap by having the system idle the minimum time.
The need to efficiently use the electricity
For utilities this means lowering the generation cost and maximize
the assets of the network such as transformers and the power grids.
For users is to lower the electrical bills through the management of
the energy consumption and demand.
Demand Management
Load Leveling
 There is a
AM
PM
12
:00
PM
11
:00
PM
:00
0
10
0
PM
9:0
PM
8:0
0
PM
7:0
0
PM
6:0
0
0
PM
5:0
PM
4:0
0
PM
3:0
0
PM
2:0
0
PM
1:0
AM
12
:00
AM
11
:00
AM
:00
0
10
9:0
0
8:0
0
7:0
© ABB Inc
March 21, 2014 | Slide 7
AM
24
22
20
18
16
14
12
10
8
6
4
AM
significant part of
the KVA capacity
that sits idle most
of the time.
Demand in MW
Battery Energy Storage Systems (BESS)
Improving the uniformity and efficiency
If the demand peaks are
provided by a Battery
Energy Storage System
then
Deferral
of new
distribution and
transmission lines
Reduce
fuel use >
Increase environmental
benefits
© ABB Inc
March 21, 2014 | Slide 8
0A
M
0A
9:0 M
0
10 AM
:00
11 A M
:00
12 A M
:00
P
1:0 M
0P
2:0 M
0P
3:0 M
0P
4:0 M
0P
5:0 M
0P
6:0 M
0P
7:0 M
0P
8:0 M
0P
9:0 M
0
10 PM
:00
11 P M
:00
12 P M
:00
AM
of new
transformer
Energy
provided by
BESS
8:0
Deferral
24
22
20
18
16
14
12
10
8
6
4
7:0
Deferral of new
generation or distribution
capacity

Demand in MW
Demand Management using BESS
Load Leveling = Better use of electricity
© ABB Inc
March 21, 2014 | Slide 9
Higher Load Factor => Better use of electricity
Peak Shaving makes the demand profile efficient
Demand profile 1
Demand profile 2
Demand in MW
Demand in MW
PM
PM
7:
00
PM
6:
00
PM
5:
00
PM
4:
00
PM
3:
00
PM
2:
00
PM
1:
00
:0
0
AM
12
:0
0
11
10
:0
0
AM
AM
Other Loads
AM
PM
PM
7:
00
PM
6:
00
PM
5:
00
PM
4:
00
PM
3:
00
PM
2:
00
PM
1:
00
:0
0
AM
12
:0
0
AM
11
AM
:0
0
10
9:
00
AM
Other Loads
Cooling Load
8:
00
Cooling Load
7:
00
Discharging Batteries
AM
10
9
8
7
6
5
4
3
2
1
0
9:
00
Charging Batteries
8:
00
7:
00
AM
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
By
charging the energy storage modules from the grid during periods of low demand
and injecting it back on to the grid during periods of high demand, the end user’s peaks
are shaved and their loads are shifted.
This
action reduces their energy charges and ultimately increases their load factor.
© ABB Inc
March 21, 2014 | Slide 10
BESS improves the Load Factor
Peak Shaving and load factor
Demand profile 1
Demand profile 2
Demand in MW
Demand in MW
 Area
Cooling Load
PM
PM
7:
00
PM
6:
00
PM
5:
00
PM
4:
00
PM
3:
00
PM
2:
00
PM
1:
00
:0
0
AM
12
:0
0
AM
11
:0
0
AM
10
9:
00
AM
Other Loads
8:
00
7:
00
PM
PM
7:
00
PM
6:
00
PM
5:
00
PM
4:
00
PM
3:
00
PM
2:
00
PM
1:
00
:0
0
AM
12
:0
0
AM
11
AM
:0
0
10
9:
00
AM
Other Loads
AM
10
9
8
7
6
5
4
3
2
1
0
Cooling Load
8:
00
7:
00
AM
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
under the curve = energy consumed. Same energy consumed for profile 1 and 2
Demand
profile 2 is more efficient, same energy consumed but lower peak demand.
Load
Factor =
Load
Factor profile 2 >load factor profile 1, then Demand Profile 2 is more effcient
© ABB Inc
March 21, 2014 | Slide 11
Energy Used in KW-hr / Time (hours in billing period)
Maximum Demand in kW
BESS improves the Load Factor
Peak Shaving and load factor
Demand in MW
Cooling Load
PM
PM
7:
00
6:
00
PM
PM
5:
00
PM
4:
00
PM
3:
00
PM
2:
00
1:
00
PM
:0
0
AM
12
:0
0
AM
11
:0
0
AM
10
9:
00
AM
Other Loads
8:
00
7:
00
AM
10
9
8
7
6
5
4
3
2
1
0

For utilities peak shaving lowers generation cost and maximize the
assets of the network such as transformers and the power grids

For users it lowers the electrical bills through the management of the
energy consumption and demand
© ABB Inc
March 21, 2014 | Slide 12
BESS improves the Load Factor
Peak Shaving benefits the utility and users
Load Factor
© ABB Inc
March 21, 2014 | Slide 13
BESS improves the Load Factor
Peak Shaving benefits the utility and users
Load Factor
© ABB Inc
March 21, 2014 | Slide 14
Demand Management using BESS
Peak Shaving
Flattening of short-term peak loads to optimize energy consumption
© ABB Inc
March 21, 2014 | Slide 15
BESS Additional Contributions
Improve electrical system’s performance
There are additional benefits besides an alternative source of energy for
Demand Management or Peak Shaving


Improve Power Factor > Optimize performance

Back up power for interruptions > Minimize downtime
© ABB Inc
March 21, 2014 | Slide 16
Power Factor
Voltage Regulation / Injection of reactive power
BESS contributes to maintain the grid voltage by injecting or absorbing
reactive power (VAR)
I (amps)
Source
KW for active
power injection
Battery Energy
Storage System
© ABB Inc
March 21, 2014 | Slide 17
KVARs for
Reactive
compensation
Loads
Power Factor
Voltage Regulation / Injection of reactive power

Power Factor (PF) = KW / KVA

Lagging power factors of less than 1.0 are caused by inductive load devices
which requires reactive power to supply the magnetizing currents.

Without corrective measures, this reactive power flows back and forth
between the loads and power source, requiring greater generating
capacity and larger infrastructure.

By compensating the reactive power then the current from the source to the
load decreases as well as voltage drops achieving a better voltage regulation.
© ABB Inc
March 21, 2014 | Slide 18
Power Factor
Voltage Regulation / Injection of reactive power
If Power
Factor
then
I (amps) then
Losses on the = better
voltage
cables
regulation
I (amps)
+
Higher KVA
availability
Source
KW for active
power injection
Battery Energy
Storage System
© ABB Inc
March 21, 2014 | Slide 19
KVARs for
Reactive
compensation
Loads
BESS Contribution to the Network
Injection of reactive power
KVA1
=157
KVA2=111
Power Flow
Source
VARs for
Reactive
compensation
Load= 94 kW
Battery Energy
Storage System
PF1
=0.6
PF2=0.85
© ABB Inc
March 21, 2014 | Slide 20
Cost of Power Interruptions

According to a 2004 Lawrence Berkeley National Laboratory (LBNL) study,
“understanding the Cost of Power Interruptions to U.S. Electricity
Consumers”, sustained and momentary interruptions on the grid system
cost the national economy $80 billion annually.

The commercial and industrial (C&I) sectors, the engine of our national
economy, bear 98 of these costs.
Total Loss due to Power Interruptions
Commercial
25%
Industrial
72%
© ABB Inc
March 21, 2014 | Slide 21
Residential
3%
BESS Contribution to the Network
Reliability: stable and continuous power supply
regardless of the supply source status

Lawrence Berkeley National Laboratory (LBNL) study found that 67%
of total economic losses are due to the frequency of short-term,
momentary interruptions of service of five minutes or less.

With several hours of discharge capacity BESS reduce customer
vulnerability to grid events by:

Provide a backup source of electricity during short-duration events

Provide ride-through service during sustained interruptions greater than
five minutes and upward of a few hours in duration

= Avoid customer economic losses due to power failure.
© ABB Inc
March 21, 2014 | Slide 22
Battery Energy Storage Systems
Most Common applications
Community
Energy
Storage
Integration
of
Renewable
Energy
Source
Summary
BESS
is a technology which contributes to raise the efficiency at every stage of the
energy chain by:

Improving the uniformity and efficiency with which electrical energy is being used
Raising Power Quality with better voltage and frequency regulation as well as
minimum interruptions


Providing a reliable source of energy to specific loads
The electrical energy stored is used for minutes up to several hours, when electric
power is most needed or most valuable for the network.

BESS makes the grid smarter by giving the option to use the electrical power
when it has the biggest impact in the network’s performance.

© ABB Group
March 21, 2014 | Slide 25