What does sustainability mean?

lizardgossypibomaManagement

Oct 28, 2013 (3 years and 11 months ago)

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Sustainable human settlements


a
decision
-
support tool

Professor Mark Swilling, Sustainability Institute

School of Public Management and Planning

Stellenbosch University

South Africa




Key shifts in human
settlement policy


From housing, to human settlements


From ‘one
-
size
-
fits
-
all’, to recognition of
context


From welfare for the poor (on the
peripheries), to
integrated
human
settlements


From unsustainable resource use, to
sustainable resource use


SI/DHS

Life Cycle Costing


“It is the intention of the National Treasury to
progressively require more detailed analyses as
funding requests are becoming larger compared
to available resources. Under these
circumstances, it is appropriate to prioritise
requests which can demonstrate the largest
benefits to our country.” (MTEF Treasury
Guidelines, 2007)


Cost Effectiveness Analysis


NPV calculation of
different ways of achieving the same goal

Unsustainable Design


low density sprawl


high unit costs of infrastructure


escalating transport costs


unhealthy & uncomfortable


costly to operate


inefficient urban design


inappropriate building materials

Tool needed to...


motivate a different way of seeing


counter the logic of the standard template


demonstrate financial viability


apply Treasury guidelines to human
settlements


Assist Dept of Human Settlements


3
year contract


open source

Building the model

As built costs of RDP housing projects (all
conventionally designed):


actual cost of house, services & land


Municipality’s operating costs


40 yrs


operating costs for household


40 yrs


size of capital subsidy (mainly DHS, but
top up from Municipality)

Costing green interventions


Solar hot water heater: R9 000 + R9 000


CFL lights: R88


Rainwater harvesting: R7 888


Hold
-
flush toilet: R5 545


Low
-
flow fixtures: R420


North
-
facing orientation: R2 500


larger north
-
side overhangs: R1 750


Ceilings: R3000


Ecological landscaping: R1000


Total cost: R93 941 (green options = R31 191)

Discount
Rate:

9%

Core Logic


higher up front costs only justifiable if they
reduce costs over the life cycle resulting in a
total cost reduction compared to BAU (as per
National Treasury requirements)
-

hence


NPV of household savings


NPV of savings on electricity & water


reduced GHG emissions (carbon tax/credits)


increased health & comfort of householders


non
-
quantifiable, but developmental



Model


220 000 units delivered nation
-
wide


Capital subsidy: R60 000


Municipal top up: R2 750


Household pays for green interventions


Conservative projections for energy/water prices

But: if subsidy increased to R90 000 to pay for
green interventions, major poverty and macro
-
economic impact

ddfdd

R -
R 100,000.00
R 200,000.00
R 300,000.00
R 400,000.00
R 500,000.00
R 600,000.00
R 700,000.00
R 800,000.00
Capital
Y 5
Y 10
Y 15
Y 20
Y25
Y30
Y35
Y40
Total
Cost Effectiveness Comparison

Sustainable
Conventional
Break even: 1 yr

Indiv. household benefit: R145 455

Energy saving: 232 320 MWh/yr

CO2 emissions reduced: 278 784 tons/yr

Water savings: 7 128 000 Kl/yr

Household savings/yr: R182 m

Only CFLs and low
-
flush fixtures


Subsidy = R60 000

R -
R 100,000.00
R 200,000.00
R 300,000.00
R 400,000.00
R 500,000.00
R 600,000.00
R 700,000.00
R 800,000.00
Capital
Y 5
Y 10
Y 15
Y 20
Y25
Y30
Y35
Y40
Total
Cost Effectiveness Comparison

Sustainable
Conventional
Solar water heaters, CFL lights, rainwater harvesting,
hold
-
flush toilet, Low
-
flow fixtures


Subsidy = R60 000

Breakeven: yr 4

Indiv. Household benefit: R387 334

Electricity saving: 673 200 MWh/yr

CO2 emissions reduced: 807 840 tons/yr

Water use: 19 419 840 Kl/yr

Household savings/yr: R522 m

Solar water heaters, CFL lights, rainwater harvesting, hold
-

flush toilet, low
-
flush fixtures, north
-
facing, larger north
-

side overhangs, ceilings, landscaping


Subsidy = R90 000

R -
R 100,000.00
R 200,000.00
R 300,000.00
R 400,000.00
R 500,000.00
R 600,000.00
R 700,000.00
R 800,000.00
Capital
Y 5
Y 10
Y 15
Y 20
Y25
Y30
Y35
Y40
Graph 1: Total Cost Effectiveness Comparison

Sustainable
Conventional
Breakeven: year 5

Indiv. Household benefit: R379 084

Energy saving: 673 200 MWh/yr

CO2 emissions reduced: 807 840

Water savings: 19 419 840 Kl/yr

Household savings/yr: R1.5 b

Plus: health & comfort benefits

Beyond minimalism


multiple income categories


city
-
wide settlement planning


more interventions: location/transport,
solar PV, bulk infrastructure (recycled
sewage, waste), restoration of eco
-
system
services, health


additional funding sources


Future

beyond minimizing damage


restoration of life


can human settlements become

drivers of the green economy?