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