Invest 2.2.1Hydropower Production model
Yonas Ghile
Why care about ecosystem services
InVEST
Hydropower production Model
Hands-on Exercise
Talk Overview
Why Care About Ecosystem Services?
InVEST: Science in a Simple ToolIntegrated Valuation of Ecosystem Services and Tradeoffs
InVEST Attributes
– Evaluate change
– Biophysical & monetary
– Open source
– Multiple services
– Spatially explicit
– Production functions
Tier 1 Tier 2 Tier 3
Models
Data
Simple Complex
Tier 0
Water Yield for
Irrigation
Drinking Water
Hydropower
Pollution Dilution
Water Yield
Questions you get answers
How much water is available?
Where does the water used for
hydropower production come from?
How much energy does it produce?
How much is it worth?
Informs Policy Makers to
Focus protection on areas that contribute the most.
Design management practices that lead to minimal loss.
Identify places where other economic activities will conflict
with hydropower production.
How much hydropower will we gain or lose under future
management or conservation plans?
Create payment programs to get most return on investment
(with Tier 2 model).
Model Architecture
Water Scarcity Model
Consumptive Use Net
Volume Hydropower and Valuation
Model
Dam HeightPrice
Energy Energy Value
TurbineEff.
E(t) P(t)
Q(t)
Water Yield
Model
Land Use Soils Climat
e
Water YieldEvapo-
transpiration
Water Yield
Precipitation
RainSnow
Fog
Inflow
TranspirationR
oot d
epth
Water Availability
Leaf typeSeasonalityPlant type
Evaporation
annual average water yield per pixel
Yjx
$####.##
Valuation
Model Strengths
Uses readily available and minimum data.
Simple, applicable and generalizable
Spatially explicit
Link the biophysical functions to economic values
Values each parcel on the landscape
Model Limitations
Neglects extremes and seasonal variation of water yield
Neglects surface-deep groundwater interactions
Assumes hydropower production and pricing remain constant
Calibration and Validation
Sensitivity Analysis to identify most sensitive parameters
Model Calibration using long term average actual data
Find land use parameters within acceptable ranges
Model parameter (Zhang constant)
Validate Model by conducting comparisons with observed data or
other model output
InVEST vs SWAT
0 100 200 300 400 500 6000
100
200
300
400
500
600
R² = 0.824150696427196
Comparison of Annual water yield between SWAT and InVEST in Texas Gulf Basin
InVEST
SWA
T
InVEST vs SWAT
Comparison of SWAT and InVESTAverage annual water yield (mm)
TULUASWAT InVEST % difference
Baseline 805.98 804.28 0.21%No conservation 816.04 765.98 6.13%Conservation 805.54 768.87 4.55%
FRAILESWAT InVEST % difference
Baseline 301.23 379.19 -25.88%No conservation 319.77 335.54 -4.93%Conservation 300.55 362.60 -20.65%
Hianan Island China
R² = 0.97
And Many Other Sites
China
Tanzania
West Coast
Hawai’i
Amazon Basin
Mexico Colombia
Ecuador Indonesia
UgandaBelize
East Coast
Hands-on SessionRun the water yield model
Hands-on SessionRun the water scarcity model
Hands-on SessionRun the hydropower and valuation model
Hands-on Session
Think how you would use the Water Yield Model in your work?
Coming up in InVEST
Regionalizing the Zhang constant
Automating calibration technique
Monthly model
Groundwater recharge index
Tier 2 water yield model
Irr(t)
E(t)
If(t)
P(t)I(t)
Sm(t)
Bf(t)
Qf(t)
S(t)
UPYRB Example
How Does it Work? Water Yield is the water depth (volume) that is NOT Evapotranspired:
WY = P – AET
It is the sum of Surface flow, subsurface flow and groundwater flow: WY = SR + SubSR + GW
Model: WY = P * (1 – AET / P )
xjxjx
xjx
x
xj
RR
RPAET
11
1
x
xx P
AWCZhangx
xxj P
ETokcR
E(t) P(t)
Q(t)
Energy Calculation
pd = d.qd.g.hd
water densitygravity constant
outflow ratehead
outflow
=0.00272
Valuation
Total Value of the Hydropower:
The Sub-basin’s Hydropower production Value:
1
0 11T
ttdded r
TCpNPVH
=
Data Requirements
Inputs Process Outputs