Slide 1: Hybrid energy systems
Hybrid energy systems Innovate 2022 Day 2 – October 20th , Stockholm ©2022 Modelon. All Rights Reserved.
Slide 2: Stéphane Velut
Stéphane Velut Industry Director, Energy At Modelon since 2009 PhD in Controls from Lund University, Sweden (2005) M. Sc. E.E, Grenoble Institute of Technology, France (1999) ©2022 Modelon. All Rights Reserved.
Slide 3: Why hybrid energy systems?
Why hybrid energy systems ? • Energy transition: large variety of technologies • Conventional power plants • Renewable energy sources • Energy Storage Systems • Sector coupling: Power-to- (gas, heat, power, X), EV to grid • Hybrid & complex systems to design, control and integrate • System simulatio
Slide 4: Fit for purpose modelling
FIT FOR PURPOSE MODELLING Acknowledge the need for models of various fidelity levels Complex Complex analysis models ©2022 Modelon. All Rights Reserved.
Slide 5: Outline
Outline • Techno-economic assessment of hybrid energy projects • Integration of renewable energy sources & storage • Power to heat – heat pump integration ©2022 Modelon. All Rights Reserved.
Slide 6: Techno-economic assessment of hybrid energy projects
Techno-economic assessment of hybrid energy projects • Microgrid package • Optimization workflow • Sizing and operation of storage • Complex hybrid energy systems ©2022 Modelon. All Rights Reserved.
Slide 7: Early stage development
Early stage development • Topology evaluations • Achievable performance • Component sizing Component • Component usage requirements Model characteristics • Power flow • Efficiency curves • Dynamics in storage mainly ©2022 Modelon. All Rights Reserved. 7
Slide 8: Microgrid package at a glance
2022.2 Microgrid package at a glance 2023.1 Sources and sinks Production & Production & Storage Carbon conversion conversion capture & Power, heat or hydrogen Power & heat Power, heat Hydrogen utilization or hydrogen ©2022 Modelon. All Rights Reserved.
Slide 9: Updates since 2022.1
Updates since 2022.1 Library scope Workflow Performance • Carbon capture • Unique model for • Full year optimization • Liquid tank H2 • Initial simulation with 1h sampling in 3- • Optimization 15 min • Liquefier • Automatic summation of costs • Gas market • Excel file import for forecast • Electroly
Slide 10: Physical modelling
Physical modelling • Efficiency-based Electrolyzer • Constant 𝑉𝑐𝑒𝑙𝑙,𝑒𝑙 = 𝐸𝑟𝑒𝑣 + 𝑟1 + 𝑟2 𝑇𝑒𝑙 𝑖𝑒𝑙 + 𝑠 𝑙𝑜𝑔10 𝑡1 + 𝑡2 𝑇𝑒𝑙 + 𝑡3 𝑇𝑒𝑙2 𝑖𝑒𝑙 + 1 • Load dependent 𝑛𝑒𝑙 𝑖𝑒𝑙 𝐴e𝑙 𝑛𝐻2ሶ ,𝑒𝑙 = η𝐹 𝑧𝐹 2 𝑖𝑒𝑙 • Static components – except for storage! 𝜂𝐹 = 2 𝑓2 𝑓1…
Slide 11: Optimization components
Optimization components Optimizer for cost & solver settings Inequality constraint block Any variable bound is interpreted as optimization constraint ©2022 Modelon. All Rights Reserved.
Slide 12: Economy modelling
Economy modelling 2022.2 • CapEx and OpEx added to all components • Economy Tab • CapEx assumed to scale linearly with component capacity • Fixed or varying operational costs • Automatic summation of all costs in Economy component • Cost normalized by life-time – to be included as integrand term in
Slide 13: Techno-economic assessment
Techno-economic assessment • Microgrid package • Optimization workflow • Sizing and operation of storage • Complex hybrid energy systems ©2022 Modelon. All Rights Reserved.
Slide 14: Optimization workflow
Guess for control and design Optimization workflow Initialization • Optimization solver needs simulation reasonable initial guess of solution Guess for all system variables for reliable convergence • Generated by specifying degrees of Dynamic freedom optimization Optimal control and design • Compone
Slide 15: Initialization versus optimization models
Initialization versus optimization models Simulation model Optimization model Boundary conditions assigned by blocks Boundary conditions set by inputs Controller for electrolyzer & fuel cell Control signals set by inputs optim = false optim = true ©2022 Modelon. All Rights Reserved.
Slide 16: Custom function
Custom function • Custom function runs the entire optimization workflow and returns the results • Found in the Resources folder of Thermal Power Library • To be placed • Local install: C:\Users\UserName\impact\custom_functions • Server install: /home/jovyan/impact/custom_functions • All settings rea
Slide 17: Techno-economic assessment
Techno-economic assessment • Microgrid package • Optimization workflow • Sizing and operation of storage ©2022 Modelon. All Rights Reserved.
Slide 18: Storage – design, operation and integration
Storage – design, operation and integration • Storage to mitigate impact of variability and uncertainty of renewables • Decoupling of demand & production • Sector decoupling • Significant research to develop new storage systems • Cheap, scalable (capacity & power), dispatchable, efficient, sustainab
Slide 19: Typical approach – Sizing and controls done separately
Typical approach – Sizing and controls done separately Control Sizing • When designing a control strategy, the assets’ size is normally • When sizing, the control strategy is normally fixed considered fixed • Sizing aims at finding the size of all assets for a minimal overall cost • Control aims at
Slide 20: Simple storage control
Simple storage control • Simple approach • If energy surplus => battery is charged • If energy missing => battery is discharged • No usage of forecast for price, load and weather • Best control strategy depends on system configuration & boundary conditions • Difficult to systematically derive contro
Slide 21: Proposed approach: Control co-design
Proposed approach: Control co-design Solve simultaneously for optimal control and optimal sizing while exploiting forecast Design Weather Control Electricity price Most critical component: • No need to derive empirical controllers • Constraint handling Load • Forecast exploitation • Interacting cont
Slide 22: Battery sizing – Problem Description
Battery sizing – Problem Description • Given expected profiles over 3 months for • Electricity price • Load • Renewable power • Find the battery size & operation • To minimize the total cost of ownership (opex+capex) Grid price does not peak at the same time as PV power ©2022 Modelon. All Rights Res
Slide 23: Evaluation of three strategies
Evaluation of three strategies Fixed controller + capacity sweep Optimal dispatch + capacity sweep Control co-design Batch of simulations Batch of optimizations Single optimization ©2022 Modelon. All Rights Reserved.
Slide 24: Experiments in Modelon Impact
Experiments in Modelon Impact Fixed controller + capacity sweep Optimal dispatch + capacity sweep Control co-design Batch of simulations Batch of optimizations Single optimization ©2022 Modelon. All Rights Reserved.
Slide 25: Results
Results Strategy Lowest cost Optimal storage size Cost at small battery Computation time [kEUR] [MWh] [kWh] [s] Simulation + sweep 12.3 [cost] 2.1 (case 2) 35.5 5s (~5*1) Optimal dispatch + sweep -101.3 [benefit] 6.2 (case 4) 32.3 100s (~5*20) Co-design -101.4 [benefit] 6.0 - 23s Fully exploited sto
Slide 26: Sensitivity w.r.t. fluctuations in grid price
DEMO Sensitivity w.r.t. fluctuations in grid price Large area in the red (no benefit) Small area in the red (no benefit) Optimal storage size at high fluctuations Best profit when large battery & fluctuation No battery best when constant grid price No battery best when constant grid price ©2022 Mode
Slide 27: Optimal operation of a hydrogen system
Optimal operation of a hydrogen system Minimize the operational cost = demand charge + grid energy ThermalPower.MicroGrid.Examples.Simulation.EconomicDispatchHydrogen • Grid import shaved to minimize demand charge • Electrolyzer mainly driven by PV • Fuel cell used to shave load peaks when no PV out
Slide 28: Complex energy system
Complex energy system • Car manufacturing company • Use case to be published at upcoming Asian Modelica conference • TCO minimization, targeting carbon neutrality • Technology options 1. Import versus on-site generation for hydrogen and power 2. Fuel cell versus battery for backup-power and peak sha
Slide 29: Renewables integration and control
Renewables integration and control ©2022 Modelon. All Rights Reserved.
Slide 30: Late stage development
LATE STAGE DEVELOPMENT • Virtual design verification • Implementation optimization • Software verification • Customer issue analysis Model characteristics • Detailed 3 phase AC representation • Current, voltage & frequency • Grid feeding & grid forming controller • Synchronization algorithm ©2022 Mo
Slide 31: Electrification Library – Battery model
Electrification Library – Battery model • From battery cell to module to pack • Scalable fidelity: from lumped packs to individual cells • Separate scaling of physical domains: core battery, thermal dynamics, electrical connections, controls • Modular core battery models • Charge capacity • Voltage
Slide 32: Thermal Power Library – Photovoltaic panel models
Thermal Power Library – Photovoltaic panel models 𝑃𝑟𝑎𝑡 𝑈(𝐼) 𝑖𝑟𝑟 𝑣+𝑅𝑠 𝑖 𝑣 + 𝑅𝑠 𝑖 𝑃 = 𝜂𝑃𝑟𝑎𝑡 (1 + 𝛼(𝑇 − 𝑇𝑟𝑒𝑓 )) 𝑖 = 𝑖𝐿 − 𝑖𝑜 𝑒 𝑎 −1 − 𝑖𝑟𝑟𝑟𝑒𝑓 𝑅𝑠ℎ Simple efficiency model Single-diode 5 parameters model Low-fidelity Current/voltage map Targeting energy…
Slide 33: Renewable and battery integration
DEMO Renewable and battery integration Time Event Inverter Battery [s] 0-1 Grid feeding, P_ref=0 Being charged by PV 1 Power outage 1-3 Grid forming, voltage Being discharged to replace grid & frequency control and meet the load demand 3.0 Connection Synchronizing with request grid 3.4-©2022 GridMod
Slide 34: Power to heat – Heat pump integration
Power to heat – Heat pump integration • Detailed heat pump model Siemens SHP-600 added in 2022.2 release • New design approach in realistic environment with closed loop system feedback! • Allows heat pump and control strategy design for new electricity market grid services for heat pumps ©2022 Model
Slide 35: New heat pump model Siemens SHP-600
New heat pump model Siemens SHP-600 • High-fidelity heat pump based on existing Thermal Power Library components useful for: • Basic design studies (heat exchanger geometry, compressor maps) • Working fluid studies • Basic control design • Constant or varying boundary conditions without direct feedb
Slide 36: Heat pump integration for design verification
Heat pump integration for design verification • Integration of the heat pump into a district heating system impacts heat pump performance and control stability: • Changing COP when change of network temperature. • Possible feedback of heat pump output provides additional challenges for heat pump con
Slide 37: Heat pump integration for studying electric grid services
Heat pump integration for studying electric grid services • Heat pumps are preferably operated at times of low electricity prices - typically high renewables share, fewer stabilizing conventional units • Heat pumps compressor can be used for demand side electricity reduction because heating systems
Slide 38: Heat pump integration for studying electric grid services
DEMO Heat pump integration for studying electric grid services Config1: Heat pump inlet is connected with return flow (30°C) Config2: Heat pump inlet is connected with remote feed (60°C) ©2022 Modelon. All Rights Reserved.
Slide 39: Conclusion
Conclusion • Challenging engineering problems related to the energy transition • Large variety of technologies • Sector coupling • Design, controls & integration challenges • Through various examples, we could should how system simulation & Modelon Impact can be used to address these challenges: • F