《環(huán)境能源技術》

1、Page 2Industry consumes 36% of global primary energy 工業(yè)部門消耗了工業(yè)部門消耗了36的全球一次能源的全球一次能源0501001502002503003504001971197319751977197919811983198519871989199119931995199719992001Global Primary Energy Consumption - Including Biomass (Exajoules)Industrialized CountriesE. Europe/FSUDeveloping CountriesSource:

2、 Price et al., 2005Share of Global 2002 Energy ConsumptionIndustry- 36%Agriculture- 3%Transportation- 22%Buildings - 39%2002Page 3 High levels of industrial production and energy use can have serious environmental consequences including: 大規(guī)模的工業(yè)生產和高能耗造成了嚴重的環(huán)境污染 air pollution 空氣污染 water pollution 水污染

3、industrial waste 工業(yè)廢物 greenhouse gas emissions contributing to global warming 溫室氣體排放帶來的全球氣候的變暖 Untapped potential energy efficiency improvements also represent economic losses不挖掘提高能效的潛力也相當于造成經濟損失 Improved energy efficiency will reduce many of these emissions and save money 能效的提高將減少污染物的排放和節(jié)約成本。Page 4

4、 Informational, estimator and management tools 信息、預測和管理工具信息、預測和管理工具Environmental Protection Agency ENERGY STAR for Industry環(huán)保署的工業(yè)能源之星環(huán)保署的工業(yè)能源之星Department of Energy Industrial Technologies Program Tools DOE工業(yè)技術項目工具工業(yè)技術項目工具Case Studies and Best Practices案例研究和最佳實踐案例研究和最佳實踐Page 5Benchmarking and benchma

5、rking tools對標和對標工具對標和對標工具 Overview回顧回顧 Examples of Benchmarking Around the World 世界對標范例世界對標范例 Different methods of benchmarking and examples of each 不同方法的對標和范例不同方法的對標和范例 Norways IEEN Program 挪威挪威IEEN項目項目 EPAs Energy Performance Indicator (EPI) 環(huán)保署的能效指標環(huán)保署的能效指標 The Netherlands Benchmarking Covenants

6、荷蘭對標契約荷蘭對標契約 LBNLs Benchmarking and Energy Savings Tool (BEST) LBNL對標和節(jié)能工具對標和節(jié)能工具Page 6Voluntary U.S. government program that helps manufacturers protect the environment through superior energy efficiency美國政府部門的自愿項目，旨在通過提高能效，幫助生產商保護環(huán)境Over 450 partner companies in a wide range of industries超過450合作公司，

7、涉及工業(yè)各個領域/index.cfm?c=industry.bus_industryPage 7 Provides energy management resources for energy managers 為能源管理者提供能源管理信息 Promotes sharing of ideas, networking & recognition 促進信息共享、網絡和共識 Energy Guidebooks - technical opportunities assessment report for plant and energy man

8、agers (next slides) 能源指南為企業(yè)和能源管理者提供技術評價報告 Energy performance indicator for enterprises to “benchmark” energy efficiency (discussed later) 企業(yè)能源性能指標，以同能效進行對標/index.cfm?c=industry.bus_industryPage 8Industry overview 工業(yè)概況工業(yè)概況Process description 工藝描述工藝描述Energy use summary 能耗概要能耗概要

9、Energy efficiency opportunities 提高能效機會提高能效機會 Brief overview of technology or practice 技術或實踐的簡要概述 Limitations on applicability (if any) 應用的局限性（如果有） Typical energy savings 典型的節(jié)能量 Typical simple payback period 典型的簡單回收期 Case study data from real-world industrial applications 工業(yè)實際應用的案例數據 References to fu

10、rther information in the public domain 出版物未來信息的參考/index.cfm?c=industry.bus_industryPage 9Written specifically for plant and energy managers 主要為企業(yè)和能源管理者提供書面的材料主要為企業(yè)和能源管理者提供書面的材料Reviewed by industry professionals and experts 由工業(yè)專業(yè)人員和專家評審由工業(yè)專業(yè)人員和專家評審Goals of the guides 指南目標指南目標

11、Reduce information barriers 減少信息障礙 Quantify energy and savings 能源和節(jié)能量化 Checklist of potential efficiency opportunities to be evaluated 評價提高節(jié)能潛力機會的清單 Starting point for more detailed analysis of selected measures 成為所選擇的措施進行更詳細分析的起點 Support in “making the case” for energy and water efficiency measures

12、 within an organization 為節(jié)能和節(jié)水措施“制造案例”提高支持 Highlight industry success stories 突出工業(yè)成功的案例/index.cfm?c=industry.bus_industryPage 10 AIRMaster+ Combined Heat and Power (CHP) Fan System Assessment Tool (FSAT) MotorMaster+ NOx and Energy Assessment (NxEAT) Process Heating Assessmen

13、t and Survey Tool (PHAST) Quick Plant Energy Profiler (PEP) Steam Systems/industry/bestpractices/software.html AIRMaster+ 熱電聯(lián)產熱電聯(lián)產 風機系統(tǒng)評價工具風機系統(tǒng)評價工具 電機電機 氮氧化物和能源評價氮氧化物和能源評價 工藝熱評價和調查工具工藝熱評價和調查工具 快速了解企業(yè)能源概況快速了解企業(yè)能源概況 蒸汽系統(tǒng)蒸汽系統(tǒng)Page 11Model the supply-side of a utility systems to

14、 identify efficiency improvement opportunities Use plant-specific dataEvaluate the operational costs for various equipment configurations and system profiles Provide estimates of potential savings gained from selected energy efficiency measures and calculates the associated simple payback periodshtt

15、p://industry/bestpractices/software.html 電力系統(tǒng)需求側管理模式，電力系統(tǒng)需求側管理模式，以確定提高能效機會以確定提高能效機會 使用工廠自己的數據使用工廠自己的數據 評價不同設備和系統(tǒng)狀況的評價不同設備和系統(tǒng)狀況的運行成本運行成本 提供預測的不同能效措施的提供預測的不同能效措施的節(jié)能潛力和計算相關的簡單節(jié)能潛力和計算相關的簡單回收期回收期Page 12Quick PEP Uses basic information about major energy-consuming systems, entered by t

16、he user, to create a report that profiles plant energy usage. Identifies specific targeted ways to economically save energy and help reduce environmental emissions associated with energy production and use.快速了解企業(yè)能源概況快速了解企業(yè)能源概況 用戶只要輸入有關主要耗能系統(tǒng)的用戶只要輸入有關主要耗能系統(tǒng)的用能基礎情況，就可以生成企業(yè)用用能基礎情況，就可以生成企業(yè)用能情況的報告能情況的報告

17、確認具體的、有針對性的、經濟可確認具體的、有針對性的、經濟可行的節(jié)能措施，有助于減少與能源行的節(jié)能措施，有助于減少與能源生產和利用相關的環(huán)境排放。生產和利用相關的環(huán)境排放。Page 13Description of where a commercially-available technology or measure has been put in place in industry Provides data on Typical energy savings Costs Simple payback period描述在企業(yè)使用過什么樣的商業(yè)可行的技術或措施提供以下的數據 典型的節(jié)能量 成

18、本 簡單投資回收期For example, a metals extrusion company in the UK replaced 5 motors with high efficiency motors. 例如：英國一家金屬擠壓公司利用高效電機替代5個電機 Savings = 11,660 kWh/year 節(jié)約 11,660 kWh/年 Costs = $2015(1992 US $) 成本 $2015(1992 US $) Payback period = 1.6 years 投資回收期1.6年From the CADDET database 來自CADDET數據庫Page 14US

19、 EPA Energy Star for Industry Program (with # of measures for each) 美國美國EPA能源之星的工業(yè)項目能源之星的工業(yè)項目 Auto assembly: 93 汽車裝配：93 Breweries: 45 釀造：45 Cement: 40 水泥：40 Corn Refining: 95 玉米加工：95 Food processing: 150 食品加工：150 Glass: 114 玻璃：114 Petrochemicals: 100 石化：100 Petroleum refining: 90 石油煉制：90 Pharmaceuti

20、cals: 102 醫(yī)藥：102 Pulp and Paper (ongoing) 紙漿和造紙（在進行中）Page 15 US DOE Industrial Technologies Program 美國能源部工業(yè)技術項目美國能源部工業(yè)技術項目 90 new technologies “for today” for aluminum, chemicals, forest products, glass, metal casting, plastics, mining, petroleum refining, steel 約有90新技術可以運用到鋁、化工、森林產品、玻璃、金屬鑄造、塑料、開采、石

21、油煉制、鋼Energy-efficient technologies for industrial systems (motors, steam, compressed air, etc.) 工業(yè)系統(tǒng)能源技術 (電機、蒸汽、空壓等)Page 16Australias Energy Efficiency Best Practice Program 澳大利亞能效最佳實踐項目澳大利亞能效最佳實踐項目.au/The European Unions Managenergy Program 歐歐盟管理項目盟管理項目 http:/ Energy Agencys C

22、enter for the Analysis and Dissemination of Demonstrated Energy Technologies (CADDET) database 國國際能源署中心的能源技術示范分析和推廣數據庫際能源署中心的能源技術示范分析和推廣數據庫 /Japans Energy Conservation Center (ECC) fact sheets with data 日本節(jié)能中心的數據表日本節(jié)能中心的數據表 /projects/promeec/td.php?link=t

23、d&page=industryNatural Resources Canada (NRCan) Office of Energy Efficiency (OEE)/ Canadian Industry Program for Energy Conservation (CIPEC) 加拿大自然資源能效辦公室加拿大自然資源能效辦公室/加拿大工業(yè)節(jié)能項目加拿大工業(yè)節(jié)能項目http:/oee.nrcan.gc.ca/cipec/ieep/index.cfmPage 17The Netherlandss SenterNovem Agency for Energy and Environment

24、荷蘭能源環(huán)境署（荷蘭能源環(huán)境署（SenterNovem） http:/www.senternovem.nl/mja/energie_efficiency/energiebesparende_maatregelen/index.aspUKs Carbon Trust http:/www.carbontrust.co.uk/energy 英國碳基金英國碳基金U.S. Department of Energy Office (DOE) of Industrial Technologies Best Practice Program /industr

25、y/bestpractices/ 美國能源部工業(yè)技術最佳實踐項目美國能源部工業(yè)技術最佳實踐項目U.S. DOE Industrial Assessment Center (IAC) database 美美國能源部工業(yè)評價中心數據庫國能源部工業(yè)評價中心數據庫/database/Page 18Tests the perception of efficiency at an enterpriseAssess energy or emission reduction potentials and cost savingsExperience with

26、benchmarking programs worldwide have shown increased attention for energy efficiency, emission reductions and performance檢測企業(yè)能效情況檢測企業(yè)能效情況評價能源或減排潛力和評價能源或減排潛力和節(jié)約成本節(jié)約成本提供對標項目的國際經提供對標項目的國際經驗，以增加對能效、減驗，以增加對能效、減排和運行的關注。排和運行的關注。Page 19Methods of comparison: Peers National or regional best practice Internat

27、ional best practiceBenchmarking can lead to Target-Setting: determining a long-range goal for improvement Based on assessment of plant energy efficiency and emissions reduction potential1.Common approach in industrialized countries比較方法比較方法 同等水平同等水平 國家或地區(qū)最佳實踐國家或地區(qū)最佳實踐 國際最佳實踐國際最佳實踐對標可導致目標的制定：確定長對標可導致目

28、標的制定：確定長期的目標期的目標 基于企業(yè)能效和減排潛力的基于企業(yè)能效和減排潛力的評價評價1.工業(yè)化國家的一般方法工業(yè)化國家的一般方法Page 20Private Sector Tools like the Solomon Index (peer to peer)NRCans Canadian Industrial Programme for Energy Conservation (CIPEC) (peer to peer)UKs Best Practice Program (peer to peer and temporal)Norways IEEN Program (peer to pe

29、er)US EPAs Energy Performance Indicator (EPI) (regional best practice) The Netherlands Benchmarking Covenants (international best practice)LBNLs Benchmarking and Energy Savings Tool (BEST) (international best practice)私營部門工具私營部門工具 Solomon 指數（對等）指數（對等）加拿大工業(yè)節(jié)能項目（對等）加拿大工業(yè)節(jié)能項目（對等）英國最佳實踐項目英國最佳實踐項目挪威挪威IEE

30、N項目項目美國美國EPA能效指數（地區(qū)最佳實踐）能效指數（地區(qū)最佳實踐）荷蘭對標契約（國際最佳實踐）荷蘭對標契約（國際最佳實踐）LBNL對標和節(jié)能工具（國際最佳實踐）對標和節(jié)能工具（國際最佳實踐）Page 21Methods of comparison: 比較方法比較方法 Peers National or regional best practice1. International best practice 對等對等 國家或地區(qū)最佳實踐國家或地區(qū)最佳實踐 國際最佳實踐國際最佳實踐Page 22Benchmark plants in several industries against ea

31、ch other 不同工業(yè)部門內企業(yè)之間對標不同工業(yè)部門內企業(yè)之間對標Based on annual company reports 基于公司年度報告基于公司年度報告00,511,521201213002120051103811036110061101211028120231300813007140071102012013110551105411018120031201411032120021102914002Company no.kWh/ltr prod. milk199619971998Page 23 Peers National or regional best practice Int

32、ernational best practiceMethods of comparison: 比較方法比較方法 對等對等 國家或地區(qū)最佳實踐國家或地區(qū)最佳實踐 國際最佳實踐國際最佳實踐Page 24 Ranks an enterprises energy performance within the US industry normalized to the enterprises configuration Based on US Census data Also based on product outputs or to other factors beyond control of p

33、lant manager, for example: Specific type or mixture of products 產品具體類型或結構產品具體類型或結構 Other factors that correlate with energy use, e.g. labor hours, weather Basis for awarding the ENERGY STAR label for a plantCompares enterprise efficiency relative to those of its industry 同相關行業(yè)的企業(yè)進行能效比較同相關行業(yè)的企業(yè)進行能效比較

34、在美國同等企業(yè)規(guī)模范圍內在美國同等企業(yè)規(guī)模范圍內，就企業(yè)的能效情況進行排，就企業(yè)的能效情況進行排隊隊基于美國的普查數據基于美國的普查數據同時也基于產品產量或基于同時也基于產品產量或基于企業(yè)管理者不可控制的其他企業(yè)管理者不可控制的其他因素，例如：因素，例如： 產品具體類型或結構產品具體類型或結構 同能耗相關聯(lián)的其他因同能耗相關聯(lián)的其他因素，例如：工時，氣候素，例如：工時，氣候成為為企業(yè)授成為為企業(yè)授“能源之星能源之星”標識的依據標識的依據Page 25Page 26Methods of comparison: 比較方式比較方式 Peers National or regional best pr

35、actice International best practice同等同等國家或地區(qū)最佳實踐國家或地區(qū)最佳實踐國際最佳實踐國際最佳實踐Page 27Goal is to become world leadersCompanies evaluate their distance from “best in the world” through studies that are overseen by SenterNovemExpert 3rd party determines international best practice energy efficiency: Top region (

36、in terms of energy efficiency) outside The Netherlands that is comparable in terms of size and plants. Average of that region is the benchmarkRanking comparable plants outside The Netherlands and taking the top 10% as the benchmarkBest operating plant worldwide. Benchmark is set at 10% below the bes

37、t plant 目標是成為世界領先者目標是成為世界領先者通過開展對通過開展對SenterNovem監(jiān)督項目監(jiān)督項目的研究，評價本公司同的研究，評價本公司同“世界上最世界上最好水平好水平”的距離的距離專家第三方確定能效國際最佳實踐專家第三方確定能效國際最佳實踐荷蘭之外的，企業(yè)規(guī)模和類型荷蘭之外的，企業(yè)規(guī)模和類型可比的地區(qū)（能效方面）。這可比的地區(qū)（能效方面）。這個地區(qū)的平均水平就是對標的個地區(qū)的平均水平就是對標的水平水平荷蘭之外可比企業(yè)的排序，排荷蘭之外可比企業(yè)的排序，排序最前的序最前的10作為對標作為對標世界運行最好的企業(yè)。對標水世界運行最好的企業(yè)。對標水平定在小于平定在小于10的最佳企業(yè)的最

38、佳企業(yè) Page 28BEST provides a benchmark score for each facility indicating its distance from international best practice in terms of energy BEST為每個設備提供了對標的核心，以表明在能效方面同國際最佳實踐為每個設備提供了對標的核心，以表明在能效方面同國際最佳實踐的距離的距離Compares only energy to best practices, keeping other variables the same. 只比對能源情況，其他變量不變只比對能源情況

39、，其他變量不變For example for cement , the best practice enterprise produces the same amount of cement, the same grades of cement and uses the same input raw materials but it (or they) uses the most efficient energy technologies to do so 例如：最佳實踐的水泥企業(yè)生產量同等，同樣標號的水泥，使用同樣的原材例如：最佳實踐的水泥企業(yè)生產量同等，同樣標號的水泥，使用同樣的原材料，但

40、使用高效技術。料，但使用高效技術。BEST allows for development of an efficiency improvement plan and target-setting BEST制定提高能效計劃和目標制定制定提高能效計劃和目標制定Page 29Global best practice 全球最佳實踐全球最佳實踐No issues with proprietary data 沒有數據所有權的問題沒有數據所有權的問題Takes into account factors specific to enterprise evaluated 考慮到所評價企業(yè)的具體因素考慮到所評價企

41、業(yè)的具體因素 We heard this: “my industry is different. You cannot benchmark my industry because there are too many variables raw materials are different, we produce different products, big facilities are different than small facilities, location affects energy use” 我們聽說過我們聽說過:“我們的行業(yè)不同。你們不能同我們行業(yè)進行對標，因為其中我們

42、的行業(yè)不同。你們不能同我們行業(yè)進行對標，因為其中存在許多不定因素原材料不同、生產不同的產品、大設備不同于小設備和存在許多不定因素原材料不同、生產不同的產品、大設備不同于小設備和能源利用受當地環(huán)境影響能源利用受當地環(huán)境影響” We created BEST 我們創(chuàng)立了我們創(chuàng)立了BESTProvides additional energy efficiency menu for target setting and energy management為目標的制定和能源管理提供進一步的能效菜單為目標的制定和能源管理提供進一步的能效菜單Allows low-cost and easy evaluati

43、on of potential 低成本和易評價的潛力低成本和易評價的潛力Page 30niBPiitotniBPiiniiiEIPEEIPEIPEEI1,1,1100100EEI= energy efficiency index 能效指數n= number of products to be aggregated累計產品數量EIi= actual energy intensity for product I 產品l實際能耗EIi,BP= best practice energy intensity for product i產品i最佳能耗Pi= production quantity for

44、product i.產品i質量Etot= total actual energy consumption for all products 所有產品的實踐總能耗 BEST Cement Benchmarking and Energy Savings Tool for the Cement IndustryDRAFTAcknowledgementsThis work was supported by the Energy Foundation and the United States Environmental Protection Agency (U.S. EPA) by Contract

45、XXX through the U.S. Department of Energy Contract under No. XXXX. other funding statements here.AcknowledgementsThis work was supported by the Energy Foundation and the United States Environmental Protection Agency (U.S. EPA) by Contract XXX through the U.S. Department of Energy Contract under No.

46、XXXX. other funding statements here.AcknowledgementsThis work was supported by the Energy Foundation and the United States Environmental Protection Agency (U.S. EPA) by Contract XXX through the U.S. Department of Energy Contract under No. XXXX. other funding statements here.AcknowledgmentThis work w

47、as supported by the Energy Foundation and the United States Environmental Protection Agency (U.S. EPA).ContinuePage 32Example boundary of analysis for cementQuarrying & Mining Materials Raw Materials PreparationFinish GrindingDrying AdditivesBagging and/or Bulk TransportPreparing Additives(gypsu

48、m, fly ash, etc.)raw materialsRaw mealclinkerPreparing FuelsClinker Makingfuelsprepared additivesdried additivescementPage 33Production Data 生產數據生產數據Raw materials input 原材料的投入原材料的投入Kiln Type 窯型窯型Clinker output 熟料產量熟料產量Cement output 水泥產量水泥產量Grades of Cement 水泥型號水泥型號Energy Data 能源數據能源數據Amount (kWh and

49、 tce) by process step 工序用能工序用能Costs (yuan/kWh or tce) 成本成本(元元/度或度或tce)Page 34Energy Intensity Index (EII)147能源強度指數能源強度指數Detailed Results 具體結果具體結果Potential for Efficiency Improvements 節(jié)能潛力Electricity (kWh saved/year) 電6,300,000Fuel (kgce saved/year) 燃料5,580,000Primary Energy (kgce saved/year) 一次能源5,6

50、00,000Cost Reduction 成本節(jié)約成本節(jié)約Electricity ($/year) 電350,000Fuel ($/year) 燃料200,000Total ($/year) 總計550,000Carbon Reduction Potential 減碳潛力減碳潛力Total (metric ton CO2/year) 總量19,000Page 35International Best Practice國際最佳實踐050100150200250300350400450Raw MaterialsPreparation原料制備ClinkerProduction熟料生產CementGr

51、inding水泥研磨Total Plant全廠能效指數 Energy Efficiency Index (EEI)Indicates technical potential表明技術潛力實踐能效指數實踐能效指數Actual energy efficiency index (EEI)Page 36Extensive menu of energy-efficiency or carbon emission reduction measures that could be implemented 可實施的能效或減排措施清單可實施的能效或減排措施清單 Cross-cutting: motor syste

52、ms, fans, compressed air, lighting 跨行業(yè)：電機系統(tǒng)、風機、空壓機、照明跨行業(yè)：電機系統(tǒng)、風機、空壓機、照明 Process-related: all major process technologies (kiln upgrades, blending) 同工藝相關：所有主要的工藝（窯爐升級，混磨）同工藝相關：所有主要的工藝（窯爐升級，混磨）Each measure措施措施 Typical energy savings per ton product (clinker or cement) 產品單耗（熟料或水泥）產品單耗（熟料或水泥） Cost of imp

53、lementation 實施成本實施成本 Typical payback period 投資回收期投資回收期Once options for implementation are selected, BEST calculates new, potential EEI for plant 一旦實施方案選定，一旦實施方案選定，BEST計算企業(yè)新的潛力計算企業(yè)新的潛力 Facilitates “scenario playing” 協(xié)助協(xié)助“方案方案” 的實施的實施 Provides a roadmap for improvement 提供改進路線圖提供改進路線圖Page 37Page 38Inte

54、rnational Best Practice國際最佳實踐050100150200250300350400450Raw MaterialsPreparation原料備制ClinkerProduction熟了生產CementGrinding水泥磨制Total Plant全廠能效指標Energy Efficiency Index (EEI)Indicates technical potential表明技術潛力Actual energy efficiency index (EEI)實踐能效指標實踐能效指標Page 39International Best Practice國際最佳實踐05010015

55、0200250300350400450Raw MaterialsPreparation原料備制ClinkerProduction熟料生產CementGrinding水泥磨制Total Plant全廠能效指數Energy Efficiency Index (EEI)Actual energy efficiency index (EEI)實踐能效潛力實踐能效潛力Potential energy efficiency index (EEI)能效潛力指數能效潛力指數Indicates technical potential表明技術潛力Page 40 Many case studies and othe

56、r information on best practices in energy efficiency for industry are available around the world While there is value in peer to peer or regional level benchmarking, benchmarking to international best practice assures goals are set to the highest standards for energy efficiency Obtaining a score is

57、only a first step, providing enterprises with information on opportunities for their plants is essential to helping them achieve their potential 世界上有許多現(xiàn)成的工業(yè)能效最佳實踐的案例和相關的其他信息 同等水平或地區(qū)的對標具有重要性，但同國際最佳實踐進行對標可以帶來最高的能效標準 獲得成績只是剛開始，重要的是為企業(yè)提供相關信息幫助他們實現(xiàn)潛力。Page 41 Christina Galitsky (CG) Lynn Pri

58、ce (LKP)LBNL Industrial End Use Analysis Website://LBNL China Group Website:BEST Website: /node/100Publications: //publicationsPage 42Pag

59、e 43NOx and Energy Assessment Tool (NxEAT)氮氧化物和能源評價工具（氮氧化物和能源評價工具（ NxEAT） Analyzes the effects of NOx reductions methods and energy efficiency practices by providing equipment inventory and configuration information. 分析減少分析減少Nox排放措施的效果，以及分析通過提供設備清單和結構信息而實施的排放措施的效果，以及分析通過提供設備清單和結構信息而實施的能效實踐的效果能效實踐的效果

60、 The tool targets specific systems, such as fired heaters, boilers, gas turbines, and reciprocating engines to help identify the NOx and energy savings potentials associated with each option. The tool also provides calculators that aid in comparisons between options. 本能源工具是針對具體的系統(tǒng)，本能源工具是針對具體的系統(tǒng)， 例如燃燒爐、鍋爐，燃氣透平和往復式發(fā)