high level explanation of smart grids and battery energy storage systems

© ABB Inc.

Energy Storage Modules Developing a smarter grid using battery energy storage systems

A smart grid is an electrical grid that gathers, distributes, and acts on

information about the behavior of all components in order to improve the

efficiency, reliability, economics, and sustainability of electricity services.

Smart Grid Value Concept

Increased Capacity – increase power delivery using existing

infrastructure

Improved Reliability – reduce number and duration of outages,

increase asset life

Greater Efficiency – improve power factor, perform voltage

management, provide bidirectional power flow

Sustainability – solutions for distributed generation as well as increased

usable life of assets through performance monitoring and analytics

Interoperability and Integration of New Technologies: Storage,

Wireless communications, FDIR, VVM, Monitoring/Diagnostics

Smart Grid Value

Priorities based on Customer Value Drivers

Demand response is an established strategy for leveling load.

There is no question but that the cheapest way to level load is to persuade

electricity consumers to turn on and off their electrical appliances, whether

they be heavy machinery, air conditioners, or electric vehicles, at exactly

the right times

The objective of the electricity service is to provide consumers with safe,

reliable electricity on demand. Consumers should be free to use electricity

whenever they like. It must be the grid that accommodates the consumer.

Smart Grid Value

Let„s analyze the challenges of the grid

Network Challenges

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Network Challenges Power Generation and Consumption

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Power distribution reliability will always be

concern and challenge for utilities,

industrials and consumer end users.

Minimize the Power Interruptions

Reduce the effect of Power Interruptions

Improve performance

Users

Utility

Power Flow

Network Challenges Balance: Energy Generated = Energy Consumed

The electricity market requires that power

generation and consumption are perfectly

balanced.

The challenge is to maintain a near real-

time balance between generation and

consumption.

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generation consumption

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t

f / V

t

kW

Network Challenges Power Generation and Consumption Ideal Scenario

Utility ideal users:

Flat Power Demand

Users ideal Power

Source:

Constant Voltage and

Frequency

Network Challenges Reality Loads are not flat, Frequency shall be regulated

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0

5

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8 10 12 14 16 18 20 22 24

Demand in MW

Time of the day

Typical Electrical Energy Consumption Pattern / Commercial

Network Challenges Efficient electrical energy use = Deferral of Investments

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If the demand peaks are

shaved > higher load

factors:

Deferral of new

generation capacity

Deferral of new

transformer

Deferral of new

distribution and

transmission lines

Reduce fuel use >

Increase

environmental

benefits

Demand in MW

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Network Challenges Energy balance challenge

Balancing

generation and

load

instantaneously

and continuously

is difficult

because the

loads and

generator are

constantly

fluctuating

© ABB Inc

2350

2450

2550

2650

2750

2850

2950

3050

3150

3250

7:00

AM

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Load in MW

Generation in MW

Network Challenges Regulation key point in the energy balance

Regulation

helps to

balance the

generation

and load

within the

control area

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Regulation in MW

-40

-30

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-10

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Network Challenges Regulation requires fast response time

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Match generation to load within the control range

Fast response time (<1 minute), Duration typically 10 minutes.

Users

Utility

Power

Flow

Regulation injection of Active

Power

Regulation kW

Network Challenges Spinning reserve: injection of active power

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The unused capacity which can be activated on the decision of the

system operator. Response time: seconds to 10 minutes. Duration from

10 to 120 minutes.

Users

Utility

Power

Flow

Spinning Reserve (Active

Power)

Spinning Reserve

kW

• Proliferation of intermittent

renewable energy around the

world such as wind and solar

energy

Network Challenges Renewable source of energy = Variability

"Courtesy of Dr Frank S Barnes - University of Colorado at Boulder"

Network Challenges Faults in the system

It is not practical to design and build electrical networks so as to completely

eliminate the possibility of failure in operation.

A fault occurs when actual current flows from one phase conductor to

another (phase-to-phase) or alternatively from one phase conductor to earth

(phase-to-earth).

Overloading - leading to overheating of insulation (deteriorating quality,

reduced life and ultimate failure).

Overvoltage - stressing the insulation beyond its limits.

Under frequency - causing plant to behave incorrectly.

Power swings - generators going out-of-step or synchronism with each

other.

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Network Challenges 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.

© ABB Inc

Industrial 72%

Commercial 25%

Residential 3%

Total Loss due to Power Interruptions

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.

Components of BESS system

Some of the battery types are:

Lead-acid, Li-Ion, Ni-Cd, Zinc

Bromine, NaCl-Ni among others.

The BMS (Battery Management

System) measures the battery

parameters to control the operation

in order to extend the battery life

and increase the safety of the

system.

Inverters rectify the AC energy into

DC to store in the batteries and then

invert the DC energy into AC energy,

single or three phase at 50 or 60

Hertz .

The energy inverted into AC power

can be connected to the electrical

network at low (<1000 Volts) or

medium voltage(<40.5 kV).

BESS Improves the performance, capacity and reliability of the grid

© ABB Inc

How?

BESS Contribution to the Network Regulation Provider: Fast injection of active power

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Users

Utility

Power

Flow

Active Power for

Regulation

Battery Energy

Storage System

BESS Contribution to the Network Reliability: stable and continuous power supply regardless of the supply source status.

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Storage will allow loads to operate through outages

Users

Utility

Power

Flow

KW from the

Energy Storage

System

X

Failure in the

main line source

or transformer

X

BESS Contribution to the Network Reliability: stable and continuous power supply regardless of the supply source status.

© ABB Inc

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.

BESS Contribution to the Network Improving the efficiency with which electrical energy is being used

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Demand in MW

Other Loads

Cooling Load

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Demand in MW

Other Loads

Cooling Load

0123456789

101112131415

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Area 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 = Energy Used in KW-hr / Time (hours in billing period)

Maximum Demand in kW

Load Factor profile 2 >load factor profile 1

Demand profile 1 Demand profile 2

BESS Contribution to the Network Allows the implementation of Demand Management actions to achieve an efficient use of electrical energy

© ABB Inc

Benefits:

a) Commercial and Industrial customers reduce their energy charges by

improving their load factor

b) Utilities reduce the operational cost of generating power in peak

periods (reducing the need for peaking units)

c) Investment in infrastructure is delayed because the system has flatter

loads with smaller peaks.

BESS Contribution to the Network Efficient use of electrical energy, Smart Grid

© ABB Inc

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 in MW

Other Loads

Cooling Load

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Demand in MW

Other Loads

Cooling Load

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101112131415

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BESS Contribution to the Network Efficient electrical energy use = Deferral of Investments

© ABB Inc

If the demand peaks are

shaved > higher load

factors:

Deferral of new

generation

capacity

Deferral of new

transformer

Deferral of new

distribution and

transmission lines

Reduce fuel use >

Increase

environmental

benefits

Demand in MW

4

6

8

10

12

14

16

18

20

22

24

7:00

AM

8:00

AM

9:00

AM

10:00 AM

11:00 AM

12:00 PM

1:00

PM

2:00

PM

3:00

PM

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PM

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12:00 AM

Demand

provided by

BESS

© ABB Group

Why is Energy Storage needed in the Wind and Solar energy Sources? Renewable energy sources like wind and solar may be part of the solution to

improve the environment, but they come at cost, They are sporadic and erratic.

Wind and Solar energy is identified as a not dispatchable. In the other hand Thermal and hydro generation are design to operate continuously , delivering power to the load. This is call dispatchable power, meaning the generator can be turned on and off as needed.

Without energy storage renewable power can not replace coal, natural gas and nuclear generation on a megawatt-for-megawatt basis.

“The U.S. Department of Energy (DOE) estimates that, for every gigawatt (GW)

of wind capacity added, 17 megawatts (MW) of spinning reserves must also be built to account for the system’s variability. Also, utilities are building capacity to meet so-called needle peaks in electricity usage that occur for only a few hours per year. It is expensive and inefficient to size capacity to these peaks and energy storage technologies can play a large role in supplanting peaking generation”

•Solar generation peak is not aligned with load‟s demand peak

BESS Contribution to the Network Solar generation‟s capacity peak

Load

Solar

Generation

"Courtesy of George Gurlaskie – Progress Energy"

BESS Contribution to the Network Renewable Energy Capacity Firming Reducing intermittency of renewable sources

Reduce the intermittency of the renewable generation, by discharging or charging

active power, making easier the integration of renewable sources to the grid.

Distributed Energy Storage (DES) is smoothing the slope of the solar farm power

generation variability. The solar farm power is showed in blue, the DES system

power in green and the smoothed output is showed in red.

" Courtesy of Sandia National Lab"

BESS Contribution to the Network Injection of reactive power

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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.


© ABB Inc

Load= 94 kW

Source

Power Flow

PF1 =0.6

PF2=0.85

KVA1 =157

KVA2=111

Source

VARs for

Reactive

compensation

Battery Energy

Storage System

Why BESS makes the grid smarter?

© ABB Inc

Users

Utility

• Frequency Regulation

• Efficient use of electrical Energy

by shaving the demand peaks

and load shifting

• Continuous Power

• Integration of the renewable

sources of energy

• Control of line congestion caused by temporary

overloads or the increasing demand of electrical

vehicles

The additional electrical power provided by BESS helps the network to

overcome the operational issues and enhance its performance.

Summary

BESS is a technology which contributes to raise the efficiency at every stage of the

energy chain by:

− Increasing the capacity factor of generation, transmission and distributions assets

− 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

− Increasing the capacity factor of renewable energy sources in order to make clean

energy available for longer periods

− Providing a reliable source of energy to communities

− 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.

high level explanation of smart grids and battery energy storage systems

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