H2FCSUPERGEN
Transcription
H2FCSUPERGEN
WP2: Hydrogen systems Sheila Samsatli, Nouri Samsatli, Nilay Shah Hub Research and Advisory Board Meeting University of Newcastle 30-31st July 2014 Our models that are relevant to hydrogen 1. Modelling of energy storage in a whole energy system • Spatio Temporal Model for Energy Systems (STeMES) 2. Hydrogen infrastructure design • Hydrogen Supply Chain Model (HSC) 3. Potential of producing renewable hydrogen from wastes and biomass in the UK • ETI Biomass Value Chain Model (ETI BVCM) Addressing the challenge of modelling energy storage in a whole energy system Future energy targets are driving the deployment of renewable technologies London Array – the world’s largest offshore wind farm A solar farm Aquamarine Power’s Oyster Wave Energy Photo credits: http://www.londonarray.com/media-centre/image-library/offshore/ http://www.solarselections.co.uk/blog/wp-content/uploads/2012/09/ROC-solar-farm.jpg The future role for energy storage in the UK, Energy Research Partnership, 2011 The intermittency challenge Source: The future role for energy storage in the UK, Energy Research Partnership, 2011 • • • Renewable energy is generated when it’s not needed Large dip in generation during high demand Peaking generators, e.g. gas turbines, used to balance supply and demand are expensive and produce GHG emissions Energy storage solution Photo credit: The future role for energy storage in the UK, Energy Research Partnership, 2011 Royal Institution Battery 1807 • • • Llyn Stwlan reservoir Hot water storage tank in the basement of a smart house Enables “wrong-time” energy generation from intermittent renewables Reduces need for peaking generators Improves energy use efficiency Specific energy (MJ/kg) 140 H2, gas at 70 MPa 120 H2, liquid Conventional fuels Synthetic fuels 100 Electrochemical 80 60 Mechanical NG at 250 MPa NG, liquid Gasoline Crude oil 40 Coal Ethanol Dry wood Methanol 20 Batteries: Pb-acid, Ni-Cd, Li-ion 0 Hydro, CAES, Flywheel 0 10,000 20,000 30,000 40,000 Energy density (MJ/m 3) Reference: Wikipedia 50,000 Source: Williams, R. Is liquid air the missing link in energy storage. Focus April 2013. Modelling challenge: the dynamics of storage technologies occur over short time scales (<hourly), very different from the time interval in energy system planning models (>yearly) Tractability is an issue! Challenges • We need a dynamic energy system model with a very wide range of time scales • Planning: years or decades • Seasonal: variations in demands and availability • Hourly (or shorter): • Dynamics of storage technologies • Variations in demands, intermittency of renewable resources • Still need to model spatial aspects • Demands and availability depend on location • Determine location/size of technologies and storage facilities • Requires integer variables • Transport of resources (centralised vs. distributed) • Very large scale model Hydrogen Supply Chain (HSC) model Natural gas Steam methane reforming Natural gas Steam Methane Reforming Coal Coal gasification Coal Coal gasification Biomass Biomass gasification Biomass Biomass gasification Electricity Electrolysis Electricity Electrolysis Liquid hydrogen Gaseous Hydrogen Tanker truck Tanker truck Tanker truck Tanker truck Railway tanker car Liquid hydrogen storage Railway tanker car Railway tanker car Liquid H2 storage Railway tanker car Tube trailer Compressed hydrogen gas storage Tube trailer Railway tube car Railway tube car Gaseous H2 storage Fuelling stations (liquid) Fuelling station Tube trailer Railway tube car Railway tube car Fuelling stations (gas) Fuelling station Tube trailer Spatial element: Great Britain represented by 34 108×108 km2 square cells Temporal element: 2015-2044 divided into 5 6-year periods Last upgrade: made it a dynamic model with time intervals of 4 seasons in a year and 4 6-hr periods in a day Example case study Summer 2015-2020 Summer 2027-2032 Summer 2039-2044 Winter 2039-2044 No. of variables > 1M, No. of constraints > 0.5M, Integers = 15k Took 3 days to solve full MIP! Inventory profile for a whole year London and the South East (cell 29) in 2039-2044 Winter Spring Summer Autumn Week Limitations of the HSC model • Multi-echelon model • Pathways inflexible • Distribution within cells too complex • Too many binary variables • Big M formulation • Too large to be extended • Adding a pipeline transport mode resulted in intractable problems • Difficult to add new technologies and resources • Still not enough time intervals Back to basics: A very simple MILP model with storage Resource balance: I U P Q Q D rch rch rp pch p rc ' ch Production capacity constraint: Ppch NPpc p c' max p rcc ' h p, c, h rch Srch Src, h1 r , c, h A simple model is intractable for the time horizon needed for a planning model! max Resource availability constraint: U rch urch r , c, h Storage capacity constraint: Srch srcmax r , c, h Objective function definition r = 3 p = 4 h c = 14 No. of integer variables = 56 h - contiguous hourly interval No. of variables No. of constraints Solution time (s) 24 6,139 3,703 7 168 42,427 25,879 744 720 181,531 110,887 22,248 2,160 544,411 332,647 >155,520 8,760 2,207,611 1,349,047 ??! STeMES • Spatio Temporal Model for Energy Systems • RTN representation of energy pathways • same framework as the BVCM and TURN model in SynCity toolkit • • • • MILP formulation Efficient representation of time Detailed storage formulation Transport losses modelled in detail Hierarchical non-uniform time discretisation Years y y=1 ss Seasons yy s=1 dd Days Hours h=1 d=1 hh s d h Total number of time intervals T = |y| × |s| × |d| × |h| e.g. for one year, T = 1 × 4 × 2 × 24 = 192 << 8760 Without storage – very easy! With storage – extra variables for initial inventories; extra constraints to link inventories within and between time levels Elec. Grid (not currently modelled) Renewable potential Rail Truck Electrolysis To another location Electricity Pipeline Fuel cell CGH2 Demand CGH2 From another location Liquefaction LH2 Regasifier Resource interconversion is modelled using tasks to represent conversion technologies and states to represent resources (STN). Underground storage CGH2 Storage Metal hydride LH2 storage Transport Transport task – used to model connections between cells i i' r1 r2 r3 r1 1 Transport r2 r2 r3 Resource r2 is transported from cell i to cell i’, which requires r1 from cell i and results in waste r3 being generated in both cells Storage An example set of storage tasks to store resource r1. r2 Put 1 r1 r3 Hold Inventory r1 Get r5 The “put” task transfers r1 from the cell to the store, requiring some r2 and producing some wastes r3 (e.g. CO2). The “hold” task maintains r1 in storage, which also requires some r2 but at less than 100% efficiency, the losses being converted to r3. Finally, the “get” task retrieves r1 from storage and delivers it to the cell, requiring some r5. STeMES prototype • • • Developed and tested for a hypothetical island of 14 50×50km cells Wind generation installed at two locations Choice of storage technologies • Salt cavern available for use as hydrogen storage facility • Other H2 storage technologies: gaseous (tank), liquid, metal hydride • Target: transport demand to be met by hydrogen (CGH2) • Objective: Minimum cost • Decisions • Location and size/number of hydrogen production and storage facilities • Operation of production facilities • Operation of storage facilities • when to charge and discharge • Transportation of hydrogen 12 13 10 11 6 7 8 3 4 5 Iltasmas 9 Cavern 1 2 14 Spatio-temporal input data Hourly demand for CGH2 (MW) in cell 07 200 Hydrogen Demand (MW) Ave. daily demand for CGH2 (MW) 180 160 140 120 100 80 60 40 20 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time of day Hourly wind generation potential (MW) Spring WD Spring WE Summer WD Summer WE Autumn WD Autumn WE Winter WD Winter WE Wind energy potential (MW) rgy potential (MW) 600 500 400 300 200 100 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time of day Results |y|= 1, |s|= 4, |d|= 2, |h|= 24 17 21 h = 113 824 16 515 76 22 23 19 18 14 12 11 234910 20 Demand (MW) 1 Demand (MW) Snapshot of the network during weekday (d=1) in spring (s=1) 2 3 4 5 6 7 8 6 7 8 9 10 11 9 10 11 12 13 14 200 150 100 50 0 1 2 3 4 5 12 13 14 15 Time of day 16 17 18 19 20 21 22 23 24 Storage charging rate (MW) Storage charging rate (MW) 250 200 150 100 50 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 12 13 14 Time of day 15 16 17 18 19 20 21 22 23 24 Time of day Storage discharging rate (MW) Hourly transport of CGH2 by pipeline Installed electrolyser capacity (3 small units) Installed underground storage capacity Storage discharging rate (MW) 250 200 150 100 50 0 1 2 3 4 5 6 7 8 9 10 11 Resource Utilisation Without storage, the scenario is infeasible BUT with storage, only a fraction of the available wind energy is needed! Wind availability (MW) 600 Spring WD Summer WE Winter WD Spring WE Autumn WD Winter WE Wind utilisation (MW) Summer WD Autumn WE Wind energy utilisation (MW) Wind energy potential (MW) 500 400 300 200 100 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time of day Spring WD Summer WE Winter WD 600 Spring WE Autumn WD Winter WE Summer WD Autumn WE 500 400 300 200 100 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time of day Cell 1 Cell 1 CGH2 production rate (MW) • The rate of operation of electrolyser is effectively constant CGH2 Production rate (MW) • • Spring WD Summer WE Winter WD Spring WE Autumn WD Winter WE Summer WD Autumn WE 50 25 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time of day Cell 1 1 160 319 478 637 796 955 1114 1273 1432 1591 1750 1909 2068 2227 2386 2545 2704 2863 3022 3181 3340 3499 3658 3817 3976 4135 4294 4453 4612 4771 4930 5089 5248 5407 5566 5725 5884 6043 6202 6361 6520 6679 6838 6997 7156 7315 7474 7633 7792 7951 8110 8269 8428 8587 Amount of CGH2 in the storage (GWh) Results |y|= 1, |s|= 4, |d|= 2, |h|= 24 Hourly inventory of CGH2 in the storage for a whole year 15 Spring 10 Summer Hour (contiguous) Winter 5 Autumn 0 Benchmarking No. of integers = 336, relative tolerance = 0.1% |s| |d| |h| a 1 1 1 24 32,823 98,631 7 b 1 1 2 24 64,959 196,911 272 c 1 2 2 24 129,399 393,639 2,543 d 1 4 2 24 258,279 787,095 69,480 No. of variables No. of constraints Solution time (s) All runs determined 45.4 MW of electrolysis capacity installed in cells 1 and 14, H2 transport by pipeline and underground storage. However, the runs with fewer time intervals underestimated the storage capacity. 15 Run c – (2 season types) 10 5 15 Run d – (4 season types) 10 5 0 Hour (contiguous) 1 160 319 478 637 796 955 1114 1273 1432 1591 1750 1909 2068 2227 2386 2545 2704 2863 3022 3181 3340 3499 3658 3817 3976 4135 4294 4453 4612 4771 4930 5089 5248 5407 5566 5725 5884 6043 6202 6361 6520 6679 6838 6997 7156 7315 7474 7633 7792 7951 8110 8269 8428 8587 0 1 160 319 478 637 796 955 1114 1273 1432 1591 1750 1909 2068 2227 2386 2545 2704 2863 3022 3181 3340 3499 3658 3817 3976 4135 4294 4453 4612 4771 4930 5089 5248 5407 5566 5725 5884 6043 6202 6361 6520 6679 6838 6997 7156 7315 7474 7633 7792 7951 8110 8269 8428 8587 Amount of CGH2 in the storage (GWh) • |y| Amount of CGH2 in the storage (GWh) • Run ID Hour (contiguous) If underground storage is not an option |y|= 1, |s|= 1, |d|= 2, |h|= 24 Demand (MW) Demand (MW) d=1 h=5 200 cell 1 2 6 7 3 4 5 6 7 10 11 8 9 10 11 12 13 14 100 0 1 2 3 4 5 8 9 12 13 14 Time of day 15 16 17 18 19 20 21 22 23 24 15 16 17 18 19 20 21 22 23 24 19 20 21 22 23 24 Storage charging rate (MW) Storage charging rate (MW) d=1 h = 19 cell 1 200 7 14 150 100 50 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Time of day Storage discharging rate (MW) Storage discharging rate (MW) • Hourly transport of CGH2 by pipeline Installed electrolyser capacity (3 small units) Installed CGH2S capacity (1 small unit each) cell 1 200 7 14 150 100 50 0 1 2 3 4 5 6 7 8 9 10 11 12 13 Time of day 14 15 16 17 18 Network is more distributed with small compressed gaseous H2 storage technologies installed in cells where generation are located and cell the with highest demand. Next steps • Real case studies (e.g. UK scenarios) • Add more resources and technologies • Exploit the full potential of the nonuniform hierarchical discretisation method • E.g. Use fewer non-uniform hourly intervals • Additional decomposition methods • Benders decomposition did not work • Test in-house approaches Source: The Electricity Storage Network. Development of electricity in the national interest. May 2014 Conclusions • Storage is a key-enabling technology for meeting the energy demands using renewable resources • Without storage the example problem is infeasible • With storage, only a small fraction of available primary resource is used and the generation technology operates effectively at a constant rate • To model storage accurately, hourly or shorter intervals are needed • In the example, four seasons are also needed • Model tractability is a big challenge • Even the simplest model cannot handle a whole year at an hourly level • Hierarchical time decomposition allows a whole year (and longer planning horizon) to be considered by exploiting periodicity in the data Potential of producing renewable hydrogen from wastes and biomass in the UK Pathways from biomass to hydrogen Bioresource Biological Anaerobic digestion Fermentation Thermochemical Metabolic processing CH3CH2OH/CO2 Gasification H2/CO CH4/CO2 CH4/CO2 CH4/CO2 Synthesis Pyrolysis Severe CH4/CO2 Bio-shift Reforming shift Reforming shift CH3OH/CO2 Photobiology Reforming shift Pyrolysis H2/CO2 High pressure aqueous H2/C H2/CO2 H2/O2 H2/CO2 H2/CO2 Reforming shift H2/CO2 • Reforming of methane (produced from biomass) to hydrogen • Electrolysis using electricity produced from biomass Reforming shift H2/C H2/CO2 Biomass Value Chain Model (BVCM) • Can be used to understand how bioenergy systems can be implemented without negative sustainability-related impacts • Models pathway-based bioenergy systems over five decades (from 2010 to 2050) • Supports decision-making around land use, interactions with food production and acceleration of bioenergy technologies Energy demand resource, technology and logistic data Optimal bioenergy value chain structure • allocation of crops to available land • choice of technologies • energy provision ( electricity, heat, hydrogen, transport fuels, biomethane) • transport networks required Model Elements: Time, Space and Climate Time • 5 decades • Up to 4 seasons per year Spatial representation • UK divided into 157 square cells of length 50km Climate scenarios • Low and medium scenarios Model Elements: Land Use Four levels of land “aggression” Level 1 as “easy, established technology” • Arable land • Heterogeneous agricultural land (e.g. Non-permanent crops associated with permanent crops ) Level 2 as “pioneering plant establishment” • Shrub and/or herbaceous vegetation association, e.g. natural grassland • Open spaces with little or no vegetation Level 3 as “challenging techno-ecological and economic land use change” • Permanent crops, e.g. fruit trees and berry plantations • Pastures Level 4 as “last resort” • Forests • Artificial non-agricultural vegetated areas (e.g. green urban areas and parks) Model Elements: Land Use Level 1 Level 2 Level 3 Level 4 3 4 Model Elements: Bioresources • Biomass data (yield, cost, and emissions) have been typically estimated at high resolution (1x1km) • High resolution data have been aggregated at a scale adequate for optimisation (50x50km) Waste potential Keys: 2010s 2020s 2030s 2040s 2050s Model Elements: Technologies • The BVCM currently includes 72 distinct technologies, some with multiple scales: pre-treatment and densification technologies technologies for hydrogen production technologies for liquid and gaseous fuel production technologies for heat, power, and combined heat and power generation waste to energy technologies carbon capture and storage technologies Model Elements: Bioresources • • • • • • • Miscanthus Short Rotation Coppice (SRC) – Willow Winter wheat Oilseed rape Sugar beet Short Rotation Forestry (SRF) Long Rotation Forestry (LRF) The BVCM currently includes 94 resources, comprising bioresources, intermediates, final products, by-products and wastes. Example of a Resource-Technology Chain: SRC Willow Gaseous fuels Anaerobic digestion Heat & power Syngas Biogas upgrading Biomethane Gasification DME Gasification + bioSNG Gasification + DME Hydrogen Biomethane (for grid) Gasification + H2 Boiler combustion (heat) Syngas boiler Biodedicated steam cycle (CHP) Electricity Biodedicated steam cycle (electricity) Cofired steam cycle (electricity) Cofired steam cycle (CHP) Gas compression Hot water Electricity & Steam Stirling engine Organic Rankine cycle IC engine Electricity & Hot water Gas turbine Dedicated biomass IGCC SRC (willow) resources Co-fired IGCC SRC (Willow) Chips SRC (Willow) Pellets SRC (Willow) Torrefied chips SRC (Willow) Torrefied pellets Liquid fuels First gen ethanol First gen biodiesel First gen butanol Pretreatment Lignocellulosic ethanol Ethanol Lignocellulosic butanol Butanol Gasification + FT diesel FT diesel Gasification + methanol catalysis Methanol Gasification + mixed alcohol process Higher alcohols Chipping Pellettising Legend Torrefaction Gasification + syngas fermentation Torrefaction + pelletising Pyrolysis oil upgrading Upgraded pyrolysis oil Hydrotreatment Naphta Gasification + FT jet/diesel FT jet Sugar-to-diesel Fuel gas Harvested resource Oil extraction Intermediate resource Pyrolysis Agricultural co-product Final product Technology Sugar extraction Pyrolysis oil Wood-to-diesel Model Elements: Logistics 4 transport modes: ship, road, rail, inland waterways UK Ports Road Tortuosity Railway Length Inland Waterways Key questions • How much hydrogen can be produced from wastes and locally-available biomass resources without undermining food production? • How much would it cost to meet the transport fuel demand using carbon neutral hydrogen from biomass? • What is the optimal pathway to produce hydrogen from biomass? Transport fuel demand Time Period 2010s 2020s 2030s Transport Fuel Demand (TWh/yr) 7.13 28.52 71.30 2040s 121.20 2050s 142.59 Case study 1: Hydrogen from locally-available biomass • Maximise H2 production • Land constraint: allocate 2% of land available in Level 1 and 15% in Levels 2-4 to bioenergy (2.35 out of 22.28 Mha ) • No import of resources abroad Case study 1: Hydrogen from locally-available biomass No constraint on GHG emissions Carbon neutral 55% of 2050 transport demand 44% of 2050 transport demand Total = Bn£ 32.7 Total = Bn£ 73.7 Case study 1: Hydrogen from locally-available biomass No constraint on GHG emissions Carbon neutral Case study 1: Hydrogen from locally-available biomass No constraint on GHG emissions Carbon neutral Case study 1: Hydrogen from locally-available biomass Land area allocated to SRC Willow and H2 Gasification plants built Carbon neutral case Total area allocated for crops Area for SRC Willow H2 Gasification H2 Gasification with CCS 2010s 2020s 2030s 2040s 2050s Case study 1: Hydrogen from locally-available biomass CO2 capture, transport and sequestration, and waste utilisation Carbon neutral case CO2 captured CO2 transport CO2 sequestered Waste wood utilisation 2010s 2020s 2030s 2040s 2050s Case study 2: 100% transport fuel demand from bio-hydrogen No constraint on GHG emissions Total = Bn£ 51.5 Carbon neutral Total = Bn£ 62.9 Case study 2: 100% transport fuel demand from bio-hydrogen Carbon neutral case What about biofuels? Total = Bn£ 71.6 Least cost, carbon neutral scenario if biofuels were to satisfy 100% of transport fuel demand Conclusions • Carbon neutral hydrogen produced from wastes and locallyavailable biomass can meet up to 44% of the transport fuel demand in 2050 without undermining food production. • CCS technologies and waste play an important role in meeting the demands for carbon neutral hydrogen from biomass. • SRC Willow and gasification plants will most likely be used in producing hydrogen from biomass. • Import of biomass resources is necessary if we are to satisfy all transport fuel demand using hydrogen from biomass.