提高电力系统灵活性—工业电气化和绿氢生产的作用.pdf

Increasing Electric Power System FlexibilityThe Role of IndusTRIal elecTRIfIcaTIon and GReen hydRoGen PRoducTIonA Report of the Energy Systems Integration Groups Flexibility Resources Task ForceJanuary 2022ESEnErgy SyStEmS IntEgratIon groupindustrial ElEctrification and GrEEn HydroGEn Production EnErgy SyStEmS IntEgratIon group ii ESENERGY SYSTEMS INTEGRATION GROUPAbout ESIGThe Energy Systems Integration Group is a nonprofit organization that marshals the expertise of the electricity industrys technical community to support grid transformation and energy systems integration and operation.More information is available at https:/www.esig.energy.ESIG Publications Available OnlineThis report is available at https:/www.esig.energy/reports-briefs.Get in TouchTo learn more about the topics discussed in this report or for more information about the Energy Systems Integration Group,please send an email to infoesig.energy.industrial ElEctrification and GrEEn HydroGEn Production EnErgy SyStEmS IntEgratIon group iii Prepared byAidan Tuohy,Electric Power Research InstituteNiall Mac Dowell,Imperial College LondonTask Force MembersWilliam Dhaeseleer,KU LeuvenElizabeth Endler,ShellAnthony Ku,NICE America ResearchNiall Mac Dowell,Imperial College LondonPierluigi Mancarella,University of MelbourneJulia Matevosyan,Energy Systems Integration GroupToby Price,Australian Electricity Market OperatorAidan Tuohy,Electric Power Research InstituteSuggested CitationFlexibility Resources Task Force.2022.Increasing Electric Power System Flexibility:The Role of Industrial Electrification and Green Hydrogen Production.Reston,VA:Energy Systems Integration Group.https:/www.esig.energy/reports-briefs.This work was supported by funds from the American Council on Renewable Energy(ACORE).The task force would like to acknowledge the valuable input and support of Karin Matchett in preparing this report.Design:David Gerratt/NonprofitD 2022 Energy Systems Integration GroupIncreasing Electric Power System Flexibility:The Role of Industrial Electrification and Green Hydrogen ProductionA Report of the Flexibility Resources Task Force of the Energy Systems Integration Groupindustrial ElEctrification and GrEEn HydroGEn Production EnErgy SyStEmS IntEgratIon group iv Contents1 Evolving Reliability Needs for a Decarbonized Grid 1 A Critical Need for New Sources of Flexibility 2 Services Provided by Industrial Electrification and Electrolytic Hydrogen Production to the Electricity System3 Industrial Electrification and Electric Power System Flexibility 3 Electricity Use in Industry Today 3 Pathways for Contribution of EIIs to Decarbonization8 Provision of Flexibility from Energy-Intensive Industries 8 Increased Demand as a Result of Increased Electrification of Industry 9 Provision of Demand Response via Industrial Loads 10 Provision of Grid Services 11 Barriers to the Provision of Flexibility by Newly Electrified Loads12 Role of Hydrogen Production in Grid Decarbonization and Flexibility 13 Potential Applications of Hydrogen in the Power System 14 Considerations for Obtaining Flexibility from Green Hydrogen in a Future High-Renewables Grid 17 Provision of Grid Services21 Advances Needed in System Planning,Operations,and Market Design24 Referencesindustrial ElEctrification and GrEEn HydroGEn Production EnErgy SyStEmS IntEgratIon group 1 Evolving Reliability Needs for a Decarbonized GridAs electric power systems continue to decarbonize and levels of renewable energy continue to rise,sources of system flexibility will become increas-ingly important.As flexibility from traditional resources may be reduced with the retirement of conventional coal-and natural gasfired generation,other sources such as demand-side flexibility will become much more important.Concurrently,the increased electrification of the overall energy system will create new loads on the electric power system,which will have the potential to contribute to such system flexibility.A key issue for electricity system operations and plan-ning is to what extent the new loads may contribute to system flexibility:whether and how these loads can shift electrical energy demand from periods when renewable electricity is less abundant to periods when there is a large amount available.A Critical Need for New Sources of FlexibilityMany decarbonization studies demonstrate the increas-ing importance of this flexibility as clean energy,particu-larly variable renewables such as wind and solar,becomes a larger portion of the resource mix(EPRI,2021;Larson et al.,2020;Williams et al.,2021).For example,hydro-gen production and the electrification of industrial loads are often cited as important sources of flexibility as levels of renewables surpass 80 or 90percent of total electricity(EPRI,2021).At such high levels of renewables,the need to shift energy across time(and potentially space),as well as the expected retirement of existing sources of flexibility,means that electric power system flexibility from the typical sources todayconventional natural gas plants,batteries,interconnection with neighboring grids,and renewables themselvesmay need to be supple-mented with new sources.The need for flexibility stems from two issues related to supply and demand balancing of electricity systems that are reliant on variable renewable electricity gen-eration:oversupply of generation,and structural energy deficits due to the variability associated with renewable generation(EPRI,2016).The first issue arises from the limited capacity factors of wind and solar.High electri-cal-energy penetration of naturally variable sources such as wind and solar photovoltaics could result in substan-tial overcapacity compared to the peak load of the elec-trical power system,which,in the absence of dedicated measures,would lead to negative net,or residual,load in industrial ElEctrification and GrEEn HydroGEn Production EnErgy SyStEmS IntEgratIon group 2 1 Net load,or residual load,are defined as the total load minus the instantaneous generation of solar photovoltaics and wind.“Net”and“residual”can be used synonymously.2 See https:/www.energy.gov/eere/fuelcells/hydrogen-shot.many hours.1 While the instantaneous excess power generation could always be curtailed,an alternative is to divert that electric power to sectors outside the classical electric grid system.This would involve using flexible electric loads to increase demand to maintain the supply/demand balance.The second issue,energy deficits,can occur in systems where there are long periods with relatively little wind or solar power compared to system demand,due to prevail-ing weather conditions.(This is likely to be particularly important for wind energy,as demonstrated recently in the UK and EU region where wind was relatively low for a long period of time.)In such circumstances,resources that are not often used will need to be available to provide energy when called upon.The ability to shift demand from periods of energy deficits to periods with more renewables available could therefore be a signifi-cant source of flexibility.The need for this flexibility will be region-specific and depend on the particular mix of generation,transmission,and load on the electricity system.The absolute quantity of flexible capacity(however de-fined)that is required to manage oversupply of renew-able energy appears low,giving opportunity for flexibility via industrial electrification,including hydrogen produc-tion,to play an important role.Currently,the electrifica-tion of industrial loads is happening slowly,and hydrogen production is still relatively expensive.However,cost declines are predicted for both of these resources,similar to what has been achieved in recent years for wind,solar photovoltaics,and battery storage.In 2021,the U.S.Department of Energy,for example,set a goal of reduc-ing the cost of electrolytic hydrogen by 80percent to$1 per kilogram in one decade.2 Services Provided by Industrial Electrification and Electrolytic Hydrogen Production to the Electricity SystemThis report lays out viable ways that industrial electri-fication and hydrogen production may play a role in providing flexibility in the future electric power system.Whereas most analysis in this space focuses on the over-all energy system and aspects such as the cost reduction required to enable more industrial electrification and hydrogen,the focus here is on describing how these tech-nologies may impact and provide services to the electric power system.The underlying assumption is a future where levels of electricity-generating renewables are high,at 70percent annual energy penetration or higher,as this is the point at which the electrification of indus-trial processes and the economic production of hydrogen will both be needed and be ready to serve this need.The intent of this report is to discuss the electric power systems perspective for these new electrical loads.Build-ing on the Energy Systems Integration Groups work on renewable integration over the past decades,this report lays out how very high levels of renewable energy could be supported by leveraging opportu-nities in the industrial sector.The report first discusses sources of industrial electrifi-cation and the potential flexibility that could be derived from the resulting large electrical loads in energy-intensive industries(EIIs).It then examines the potential role of hydrogen production in providing flexibility to the future high-renewables system,with a focus on green hydrogen.The report concludes by summarizing high-level operations and planning issues for power systems and identifying key areas needing further work.The ability to shift demand from periods of energy deficits to periods with more renewables available could be a significant source of flexibility.The need for this flex-ibility will be region-specific and depend on the particular mix of generation,transmis-sion,and load on the electricity system.industrial ElEctrification and GrEEn HydroGEn Production EnErgy SyStEmS IntEgratIon group 3 Industrial Electrification and Electric Power System FlexibilityEIIs are at the foundation of the broader economy and enable a vast amount of other industrial activ-ity.They provide the basis for many chemicals used in industry,produce construction materials,support agriculture and paper industries,and far more.They link to all other economic sectors,are themselves extensively interlinked,and are deeply connected within the broader energy system(see Figure 1,p.4).EIIs are often very carbon-intensive,and they can be harder to decarbonize than other sectors such as the electricity sector.One option for their decarbonization is to electrify these industrial loads and rely on clean electricity to power the loads.This is not simple,however.Any significant change in the provision of energy in these industries,their operation,and their cost structure will have profound and systemic ramifications across the broader economy(Lovins,2021a;2021b).Electricity Use in Industry TodayThe share of electricity among all energy inputs in the industrial sector varies widely,with a general shift toward increased electricity use in the industrial sector expected in the near to medium term.The lowest share,at 14per-cent,is in non-metallic minerals(mostly cement,glass,and ceramics industries),and the highest share of 65percent is in non-ferrous metals,composed mostly of primary aluminum production that uses electrolysis to reduce aluminum from aluminum oxide.Electricity is mostly used for machine drives,to provide electrical control of industrial processes,and for some means of electric heating(including electric arc,infrared radiation,elec-tron beam,and plasma heating).Some industrial electric technologies use electricity as an alternative to directly providing heat,for example,using mechanical work in mechanical vapor recompression heat pumps or separating materials using selectively permeable membranes rather than using heat.Other means of material separation use electric potential gradients(e.g.,electrodialysis)or electrolysis(e.g.,electrolytic refining of alumina and copper).The increasing demand for renew-able energy technology will itself lead to a general shift toward higher electricity use in the industrial sector due to the increased production and refining of rare earth elements and potential increase in the recycling of metals.Pathways for Contribution of EIIs to DecarbonizationCurrently,industry accounts for more than one-third of the global final energy use,making it an essential sector to decarbonize.However,EIIs,owing to their heteroge-neity and the need for high-quality heat to transform raw materials into more refined materials,are particularly challenging to decarbonize.In contrast to the electric power sector,where low-carbon electricity is used by industrial ElEctrification and GrEEn HydroGEn Production EnErgy SyStEmS IntEgratIon group 4 Note:The red text refers to the EIIs discussed in this report.Source:Wyns,Khandekar,and Robson(2018).FIGuRE 1Connections Between Energy-Intensive Industries and the Rest of the Economyindustrial ElEctrification and GrEEn HydroGEn Production EnErgy SyStEmS IntEgratIon group 5 loads in exactly the same way as fossil fuelbased elec-tricity,the concept of a baseline or“archetypal”industry facility is difficult to define.Facilities electrical and non-electrical loads,operating procedures,and practices vary from location to location and have a significant time dependence regarding when they are used.In addition,many facilities within a given sector use multiple fuel sources and have multiple point sources of carbon dioxide(CO2).It is important to note that EIIs have already played an important role in emissions reductions.Between 1990 and 2015 in Europe,EIIs reduced their greenhouse gas emissions by 36percent,representing approximately 28percent of economy-wide reductions,despite the fact that EIIs were responsible for only 15percent of total greenhouse gas emissions in the European Union in 2015.To date,EII emissions reductions have come about through a combination of improvements in energy efficiency,fuel switching,and plant closures or reduced output,largely as a result of the 2008 financial crisis.There are many pathways to further emissions reduc-tions,as shown in Table 1.In addition to further energy efficiency improvements,process integration,and the use of carbon capture,utilization,and storage technologies(Wei,McMillan,and de la Rue du Can,2019),electri-fication has the broad potential to contribute across all sectors,through both heat and mechanical processes and through electrolysis for hydrogen production.industrial ElEctrification and GrEEn HydroGEn Production EnErgy SyStEmS IntEgratIon group 6 HeatA large proportion of industrial emissions arise from the provision of heat(or thermal power).Given the rapidly improving economics of renewable/low-carbon electrical power and energy storage,the electrification of EII heating needs is becomi