Distributed, flexible generation - Central Electrical Authority

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Distributed, flexible generation - Central Electrical Authority

International Conclave on Key Inputs for Accelerated Development

Of Indian Power Sector for 12 th Plan and beyond

19 th August 2009, New Delhi

Distributed, flexible generation

P V Krishna


Adequacy of power

• Thus far, adequacy and reach of power has drawn main

attention while planning

• Adding coal-hydro-nuclear baseload generating

capacity, while necessary, may just not be sufficient.

• Especially since urban India now accounts for over half

the country‟s GDP, and its electricity consumption

peaks during the day, and drops significantly at night

and on weekends. A characteristic that does not very

well suit plants that are built to run baseload

• We now need to build in reliability and flexibility


Going beyond adequacy

Reliability

• modern “digital economy” needs high reliability

• primary/secondary control & spinning reserves

• building reserve capacity

• reliability targets, establishing metrics for monitoring & improving

Flexibility

• dynamic response

• coping with demand variations & supply variations

• compensating for unpredictable variable resources, renewables, wind

• doing the job outside the baseload range (starts & stops)


Going beyond adequacy – load duration curve

• It can be seen that the constant base-load (that is

present for 100% of the time) is about 50%

of maximum demand

• For 50% of the time, the load is around 75% of

maximum demand.

• The peak demand (top 15% of MW) lasts around

15% of the time.


Load Duration Curve – California

17% MW for 5% time!


Hourly Load (MW)

Going beyond adequacy

Impact of 18 GW of wind on base-load generation

Load Duration Curve

140 %

Reserve

capacity

Gas and oil

Peaking & reserve (GW)

capacity

Local generation

Fast, flexible!

120 %

100 %

Gas / Oil

80 %

CHP

60 %

Coal or CCGT

Coal

Base load (GWh)

capacity

Low marginal costs!

40 %

Nuclear

20 %

Hydro / Wind

1,000 2,000 3,000 4,000 5,000 6,000 7,000 8,000

Annual Hours

0 %


Decentralised power - a Paradigm shift

Distributed Flexible Generation - values

High thermal efficiency:

Combined cooling, heating

and power

Load centre plants:

Flexible baseload.

Address peaking shortages

Better grid support

& grid stability

Islanding from cascade trips

Lower risk of

“stranded assets”

Lower vulnerability,

Risk mitigation

Low “water stress”

Low CO 2

opportunity

Load centre plants:

Reduced T&D losses

Reduced transmission

investments

Staggered investments

Modular additions

Flexible operations

Entrepreneurial activity

Low gestation,

Financial closure simpler

Rapid capacity addition


Distributed, flexible generation – key applications

Combined cooling,

heating and power

Peaking, intermediate

(and flexible baseload)

Rural electricity

Enabling renewables


Decentralised power - a Paradigm shift

1.Combined cooling, heating and power

Steam/ Water

Drum

Chilled water

Consumer

Feedwater Tank

Economizer

Boiler/ hot water gen

Engine

HT Water

Cooler

Chilled Water

Consumer

Lubricating

Oil Cooler


1.Combined cooling, heating and power – fuel natural gas

Fuel 100 kCal

Gas 100 kCal

38% efficiency

T&D

losses

20 - 30%

38 kCal power

Power

45 kCal

Chilling

25 kCal

26-30 kCal

End

consumer

Net thermal

Efficiency

= 26-30% approx

End

consumer

Net

Thermal

Efficieny

70%

70 kCal

Low carbon footprint

Central pit-head

Coal plant

Distributed

CCHP


Decentralised power - a Paradigm shift

1. Combined cooling, heating and power

Deployment results are best achieved

at dense & concentrated urban loads:

• airports

• IT Parks, ITES

• IDCs, server farms

• large commercial complexes

• hospitals

• hotels

• malls & multiplexes

• cluster residential development

• university campus

• and so on…..

1. Direct reduction in MWh e

consumption

2. Overall efficiency upto 70%

3. CO 2 footprint down from ~1 kg/kWh e

to 0.25 to 0.4 kg/kWh e (gas fuelled)

4. Minimum use of diesel standby power

5. Nil or reduced transmission

investment

The positives

Fuelled by domestic natural gas


1. Combined cooling, heating and power

“For fast growing China and India, the CHP shares of

electricity generation could rise to 28% and 26%

respectively by 2030. Currently CHP makes up about

13% of electricity generated in China and 5% in India

(IEA 2008b). This provides an excellent opportunity for

profitable investment in low carbon technologies.”

Source: IEA Publication 2009 - Cogeneration and District Energy. Sustainable energy

technologies for today … and tomorrow


Decentralised power - a Paradigm shift

2. Peaking, intermediate, flexible baseload plants


MW

PERIOD -

05.05.2008

16.06.2008

26.07.2008

07.09.2008

21.10.2008

29.11.2008

09.01.2009

15.02.2009

25.03.2009

3. Enabler of renewables (eg Tamil Nadu, annual)

Wind generation- TN 2008-9

4500

4000

3500

3000

2500

2000

1500

1000

500

0

Total installed

capacity

During lighting peak

7pm

During morning peak

8am

period


3. Enabler of renewables, intra-day (Colorado, USA)


4. Rural electricity

Decentralised power - a Paradigm shift

• Biomass based generation (boiler + STG)

• Biomass gasification (gasifiers + engine generator sets)

• Liquid biofuels based generation

jatropha, pongamia, honge, castor…

straight non-edible oils (no transesterification!)

alternate to biodiesel as transport fuel

liquid fuels in engine generator sets, oilcake in

Rankine cycle or in gasifiers


Recommendations – distributed flexible generation

1. The 12th and 13th Plans must focus on ways to improve „reliability‟ apart from ensuring

„adequacy”. The characteristics of a reliable system (24x7) must be defined and communicated.

Clear metrics must be introduced to track and monitor the performance of the system.

2. Emphasis on „distributed flexible generation” and “flexibility in grid management”. Clear targets

must be set for addition of distributed flexible generation plants, as a percentage of total planned

addition. (eg “CHP Directive” in EU)

3. Plans to provide for unique peaking solutions, in addition to just base-load plants. Clear targets

must be set for addition of peaking plants in every state or Discom area. To begin with, a target of

10,000 MW in the 12th Plan. Tax & duty exemption on fuels for such capacity additions

4. Extend mega power policy benefits to Distributed flexible generation.

5. In situ natural gas fuelled Combined Cooling Heating and Power plants (CCHP) must be made

mandatory for large buildings with connected loads over 25 MW. Feed in rights introduced.

6. Distributed flexible generation plants should be allowed to partner wind energy plants in a hybrid

solution. The resulting power would be „clean‟, „firm‟ and „schedulable”.

7. Out of the gas allotted to the power sector, at least 40MMSCMD must be earmarked for

distributed flexible generation in the 12th Plan.

8. Rural electricity with biomass and liquid biofuels – use of straight non-edible oils for electricity, and

the creation of “local rural ecosystems”


Distributed flexible generation

Thank You

Jai Hind

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