T9.7 Multi-criteria evaluation of emission control strategies in semi-hypothetical case city archetypes

Lian Scholes, Mike Revitt and Eva Eriksson

• Decision-support tool

• Can incorporate non-financial information

• Performance matrix: possible solutions scored against range of criteria

• Can apply weightings to reflect stakeholder preferences

What is multi-criteria analysis (MCA)?

Weightings

Example matrix: DayWater MCC

DayWater website: http://daywater.in2p3.fr/EN/

Weightings

Example scored matrix

DayWater website: http://daywater.in2p3.fr/EN/

• Urban

DayWater website: http://daywater.in2p3.fr/EN/

• Decision-making context: semi-hypothetical case city of EI• Options: ECS1 - 6• Criteria:

– Technical feasibility: available (1), under development (2),

does not exist (3)– Technical efficiency: >95% (1), 80-95% (2), <80% (3)– Costs: <100M€ (1), 100M – 1000M€ (2), >1000M€ (3)– Environmental impact: results of the SFA

• Allocation of scores – pollutant and context specific• Development of weights – this afternoon’s task!

ScorePP MCA matrix for Cd

• EI – emerging economy building technological and institutional capacity, elevated background levels of Cd

• ECS1 - Baseline • WWTP services 90% of the population • IWW is 468M m3; 3% is BAT treated• 0.005% (2.5 ha) covered by stormwater ponds• All systems paid off so only O&M costs

• ESC2 - Legislation

– 100% connection to WWTP

– BAT applied to 12% IWW

Matrix for Cd: assumptions made (1)

• ECS 3 – ECS2 + Voluntary initiatives - successful campaign to reduce use of Cd in artists’ paints

• ECS 4 – ECS2 + BAT applied to 100% IWW

• ECS5 – ECS2 + surface area covered by range of stormwater BMP types increased to 0.05% (25 ha)

• ECS6 – ECS2 + Advanced WWT applied to 50% of WW

Matrix for Cd: assumptions made (2)

Matrix for Cd in EI: ‘raw data’

ECS1 Baseline

ECS2 Legislation

ECS3 Voluntary Initiatives

ECS4 BAT ECS5 Stormwater

BMPs

ECS6 Advanced

WWT

Technical feasibility

Default scenario

Legislation but exemptions

Successful campaign

Covered in BREF

Data available

Removed by nanofiltration

Technical efficiency

Elevated background levels, PHS

Building technological capacity

Emerging ‘green’ awareness

Heavily industrial-ised

Selected BMPs with high removal

e.g. 90% removal by nanofiltration

Financial aspects

WWTP O&MBMP O&MIWWT O&M

WWTP - plant, connection,O&MIWWT capital, O&M

e.g. Publicity campaign to install battery recycling technology

IWWT capital, O&M

BMP capital, O&M

e.g. nanofiltration capital, O&M

Environmental impact

Results of SFA

Results ofSFA

Results of SFA

Results of SFA

Results of SFA

Results of SFA

Matrix for Cd in EI

ECS1 Baseline

ECS2 Legislation

ECS3 Voluntary Initiatives

ECS4 BAT

ECS5 Stormwater

BMPs

ECS6 Advanced

WWTTechnical feasibility

1 2 1 1 1 1

Technical efficiency

3 3 3 2 3 2

Financial aspects 1 2 2 3 2 2

Environmental impact

3 2 2 2 1 2

Total score 8 9 8 8 7 7

Scores: range from 1 (best performance) to 3 (worst performance)

Order of preference: Advanced WWT and Stormwater BMPs BAT and Voluntary Initiatives

Matrix for Cd in EI

ECS1 Baseline

ECS2 Legislation

ECS3 Voluntary Initiatives

ECS4 BAT

ECS5 Stormwater

BMPs

ECS6 Advanced

WWT

Weightings (%)

Technical feasibility 1 2 1 1 1 1 10

Technical efficiency 3 3 3 2 3 2 10

Financial aspects 1 2 2 3 2 2 60

Environmental impact

3 2 2 2 1 2 20

Total weighted score

160 210 200 250 180 190 100

Order of preference: Stormwater BMPsAdvanced WWTVoluntary InitiativesBAT

Matrix for Cd in EI

ECS1 Baseline

ECS2 Legislation

ECS3 Voluntary Initiatives

ECS4 BAT

ECS5 Stormwater

BMPs

ECS6 Advanced

WWT

Weightings (%)

Technical feasibility 1 2 1 1 1 1 10

Technical efficiency 3 3 3 2 3 2 50

Financial aspects 1 2 2 3 2 2 20

Environmental impact

3 2 2 2 1 2 20

Total weighted score

240 250 240 210 220 190 100

Order of preference: Advanced WWTBATStormwater BMPs Voluntary Initiatives

PROS

• Structured, traceable and auditable analysis

• Copes with large amounts of data/information in differing forms and reporting units

• Can incorporate a variety of stakeholder interests

• An understandable communication tool

CONS

• Dynamic problems simplified

• Is it too subjective?

• Static picture: lacks time dimension

• How are outcomes to be interpreted? Best or preferred option need not necessarily be that which provides the most e.g. cost-benefits

MCA – pros and cons