1 large scale vs small scale

8/7/2019 1 large scale vs small scale

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District Heating and Cooling, including the integration of CHP

INTERNATIONAL ENERGY AGENCY

2002 Novem 1

ANNEX VIIANNEX VIIA COMPARISON OF DISTRIBUTED CHP/DHA COMPARISON OF DISTRIBUTED CHP/DH

WITH LARGE SCALE CHP/DHWITH LARGE SCALE CHP/DH

Paul WoodsPaul Woods

Oliver RileyOliver Riley

Parsons Brinckerhoff LtdParsons Brinckerhoff Ltd


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District Heating and Cooling, including the integration of CHPI I C

2002 Novem 2

bjectives of Studybjectives of Study

Review of CHP/DH experiences in partner countries

Review of current CHP technologies, especially

small-scaleEconomic and environmental comparison of

centralised vs distributed CHP/DH solutions


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2002 Novem 3

ScenariosScenarios

The heat and power demands of the buildings within a generic citycould be met by:

A City-wide DH system supplied by a single large CCGT powerstation at the city edge

B 10 separate District level DH systems supplied by smallerCCGT power plants

C 50 Local DH systems supplied from spark-ignition gas-engineCHP

D individual Building CHP systems using spark-ignition gas-

engines for apartment blocks and Stirling engines for individualhouses (circa 100,000 units)

Balance of electricity demand/supply by trading on national grid


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2002 Novem 4

ScenariosScenarios


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2002 Novem 5

Factors influencing the outcomeFactors influencing the outcome

Implementation and marketing

Impact on gas and electricity

networks

Local environmental impact (e.g.noise, NOx)

Security of supply of heat and

electricity

Potential for incorporation of

renewables and alternative heatproduction technologies

CHP unit type and size

CHP unit utilisation

CHP unit performance

characteristics

CHP capital and operational costs

Extent and design of required DH

infrastructure

DH capital and operational costs

Energy transmission losses

Cost of fuel

Value of electricity


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2002 Novem 6

Generic city derived from European dataGeneric city derived from European data

0

10

20

30

40

50

60

70

80

90

100

150

175

200

225

250

275

300

325

350

375

400

425

450

475

500

525

550

575

600

625

650

675

700

725

750

775

800

825

850

875

900

925

950

975

1000

1025

1050

1075

1100

1125

1150

1175

1200

Mor

e

City Population (k)

Frequency Increasing

size of city


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2002 Novem 7

Inner city heat demand (GWh)

123

93

164

71

Inner City heat demand

ModellingModelling energy demand assessmentenergy demand assessment

Domestic

Commercial& retail

Industrial

Institutions

Outer city heat demand (GWh)

1,

17

296

144

93

Outer City heat demand

Inner city electrical demand (GWh)

31

228

2

4

36

Inner City electrical demand

Outer city electrical demand (GWh)

349

731

241

1

Outer City electrical demand


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2002 Novem 8

ModellingModelling CHP performance characteristicsCHP performance characteristics

SCHEME CITY-WIDE DISTRICT LOCAL BUILDING BUILDING

Description CCGT CCGT SIGE SIGE Micro

Capacity (kWe) 400000 70000 5100 305 0.85

Euro/kW installed

(Euro k/kW)628 755 859 1,506 2,940

Combined efficiency 89% 88% 84% 84% 96%

Electrical efficiency

(NCV)54% 53% 46% 35% 11%

Thermal efficiency

(NCV)35% 35% 38% 49% 85%

Z-factor 6.15 6.27 n/a n/a n/a


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2002 Novem 9

CHP Simulation ModelCHP Simulation Model

0

200,000

00,000

00,000

00,000

,000,000

,200,000

,

00,000

,

00,000

0

2 2

2

20

0

0

2

2

0

2

00

2

0

Num

er of hours

er

ear

Load(

)

iversifie

U

iversifie

Di

ersified heat em (!

eek "

) # er $ lant

-

%00,000

200,000

&00,000

'

00,000

(

00,000

)00,000

000,000

1 00,000

200,000

%,000,000

2 2

Hour of Da3

A

4 erageHeat

Demand(

5

6)

J7 8

Fe9

@

7

r

AA

r

@

7 B

JC 8

JC

l

AC D

E

eA

F

ct

Nov

G

ec

DSF= 0.3

Diversity factor on peak = 63%


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2002 Novem 10

Energy balance resultsEnergy balance results heat supplyheat supply

500

1000

1500

2000

2500

3000

City-wide District Local BuildingH

lternative

GWh

Consumer demand DH heat losses CHP heat recovery Boiler top-up heat

0


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2002 Novem 11

Energy balance resultsEnergy balance results electricity supplyelectricity supply

-2500

-2000

-1500

-1000

-500

500

1000

1500

2000

2500

3000

3500

4000

4500

City-wide District Local Building Alternative

GWh

Demand at buildings HV losses LV losses DH Pumping power Elec production Net import

0


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2002 Novem 12

Environmental results summaryEnvironmental results summary

0.00

0.20

0.I0

0.P0

0. Q 0

R.00

R.20

R.

I0

R.

P0

S

T U V W

XITY INN

WR

XITY

UUT

WR

XITY

TCO2erannum

X

itY

-

ia

eb

istrictV

occ

ld e

ila

if

g

Alterf

c

tive


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2002 Novem 13

Economic results summaryEconomic results summary

- h , i 00,000

- h ,000,000

- 2, i 00,000

- 2,000,000

- p , i 00,000

- p ,000,000

- i 00,000

0

q

r s

t u

v ITY INNu

R v ITY s UTu

R v ITY

NP

(x1

)

v itw

-x iy e

istrictt

oc l

il y i

Alter

tive


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2002 Novem 14

ConclusionsConclusions

City-Wide CHP (400MWe CC )

Most economical on a large scale lifecycle efficiency

savings offset capital cost of city-wide DH infrastructure

Delivers greatest environmental benefits

Potential for incorporating alternative heat production

sources i.e. energy from waste, biomass, fuel cells

equires high degree of regulation to sanction necessary

infrastructure works and ensure high levels of take-up


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2002 Novem 15


District CHP (70MWe CC )

Delivers environmental and lifecycle cost savings over

other CHP scenarios except City-wide scheme

In Outer City cannot compete economically with alternative

scenario (gas boilers)

Potential for incorporating alternative heat production

sources i.e. energy from waste, biomass, fuel cells

equires high degree of regulation to sanction necessary

infrastructure works and ensure high levels of take-up


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2002 Novem 16


ocal CHP (circa 5MWe SI )

Not cost effective generally but more competitive in Inner

City

Largest part of the DH infrastructure cost is at Local level

SIGE not as good environmentally as CCGT due to lower

efficiency and lower proportion of CHP heat supplied

Less regulation required than for larger schemes as only a

few anchor customers need commit initially

Local environmental impact must be minimised with careful

design


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2002 Novem 17


Building CHP (15kWe Stirling to 2MWe SI )

voids DH infrastructure costs and minimises losses

because energy is consumed near to the source of

production

Low electrical efficiency

More economical than Local CHP in low density Outer City

areas

Potential costs to upgrade electricity network if high

penetration of distributed generation is to be achieved

Potentially higher electrical efficiency in future with fuel

cells

Documents

1 large scale vs small scale