Invest 2.2.1 Hydropower Production model YonasGhile
Talk Overview • Why care about ecosystem services • InVEST • Hydropower production Model • Hands-on Exercise
InVEST: Science in a Simple Tool Integrated Valuation of Ecosystem Services and Tradeoffs
InVEST Attributes • Evaluate change • Biophysical & monetary • Open source • Multiple services • Spatially explicit • Production functions Models Simple Complex Data Tier 0 Tier 1 Tier 2 Tier 3
Water Yield for Hydropower Irrigation Drinking Water Water Yield Pollution Dilution
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 Land Use Climate Soils Water Yield Model E(t) P(t) Evapo-transpiration Water Yield Price Turbine Eff. Dam Height Consumptive Use Q(t) Net Volume Hydropower and Valuation Model Water Scarcity Model Energy Energy Value
Water Yield Transpiration Precipitation Evaporation Rain Leaf type Snow Plant type Seasonality Fog Yjx Root depth Inflow annual average water yield per pixel Water Availability
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
Hianan Island China R² = 0.97
And Many Other Sites West Coast East Coast Hawai’i Belize China Colombia Uganda Mexico Ecuador Amazon Basin Tanzania Indonesia
Hands-on Session • Run the water yield model
Hands-on Session • Run the water scarcity model
Hands-on Session • Run the hydropower and valuation model
Hands-on Session Think how you would use theWater 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 I(t) P(t) Irr(t) Sm(t) Qf(t) E(t) If(t) S(t) Bf(t)
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 ) E(t) P(t) Q(t)
Energy Calculation outflow rate head pd = d.qd.g.hd gravity constant water density outflow =0.00272
Valuation • Total Value of the Hydropower: • The Sub-basin’s Hydropower production Value: =
Data Requirements Inputs Process Outputs