1、May 2022Cost and Technology Trends for Onshore Wind Power in Japan2 Acknowledgements In compiling this report,several power plant operators provided us with technology and cost data of their plants,as well as advice regarding analysis.Although we are not able to list the names of each individual,we

2、would like to express our sincere gratitude to everyone who cooperated in this study.Part of this work was supported by JSPS KAKENHI Grant Number 20H00649 and by the German Federal Ministry for Economic Affairs and Climate Action.Authors Keiji Kimura,Senior Researcher,Renewable Energy Institute Tets

3、uo Saitou,Senior Research Fellow,Renewable Energy Institute Disclaimer Although we have taken all possible measures to ensure the accuracy of the information contained in this report,Renewable Energy Institute shall not be liable for any damage caused to users by the use of the information contained

4、 herein.About Renewable Energy Institute Renewable Energy Institute is a non-profit think tank which aims to build a sustainable,rich society based on renewable energy.It was established in August 2011,in the aftermath of the Fukushima Daiichi Nuclear Power Plant accident,by its founder Mr.Son Masay

5、oshi,Chairman&CEO of SoftBank Corp.,with his own resources.3 Table of Contents 1 Introduction.4 2 Onshore wind power technology trends in Japan.6 2.1 Summary of data.6 2.2 Trends in onshore turbine technologies.7 2.3 Capacity factor.10 3 Trends in Onshore Wind Power Costs in Japan.13 3.1 Installatio

6、n costs.13 3.2 Wind turbine costs.14 3.3 Foundation and site preparation costs.17 3.4 Electrical work and transmission infrastructure costs.19 4 Conclusion:Summary of Analysis Results and the Potential for Reducing Onshore Wind Power Costs in Japan.22 5 References.24 4 1 Introduction Problem recogni

7、tion and study objectives Japan has declared its commitment to carbon neutrality by 2050 and positioned renewable energy as“decarbonized power sources under practical use”in its 6th Strategic Energy Plan(2021),stating that it will“address maximum introduction of renewable energy as major power sourc

8、es on the top priority”in 2050.In addition,in the governments 2030 energy supply-and-demand forecasts that were released at the same time,renewable energy is projected to account for approximately 20%of primary energy supply and 36-38%of total electricity generated.Onshore wind power is a promising

9、energy source that will be indispensable to the firm achievement of carbon neutrality in Japan,and promoting its spread and improving its economy are key challenges.Installed onshore wind capacity in Japan is approximately 5 GW at the end of 20211,and in the long-term energy supply-and-demand foreca

10、sts,it is projected to increase to around 16 GW by 2030(in the“enhanced policy responses”scenario).Even so,onshore wind power would still only account for 3%of electricity generation as forecast for 2030.Further promotion and expansion are needed.At the same time,according to the governments Power G

11、eneration Cost Verification Working Group,onshore wind power costs are calculated at 21.6 yen/kWh in 2014 and 19.8 yen/kWh in 2020,so cost reductions have made almost no progress(Power Generation Cost Verification Working Group,2015;2021).2030 generation costs are estimated at 9.9-17.2 yen/kWh,which

12、 is a wide range,and this suggests a high degree of uncertainty.Generating costs for 2030 were estimated by applying reduction rates for construction costs used by international institutions in their declining cost scenarios(Figure 1)to Japan.The international price convergence case was also taken u

13、p to consider the possibility of even lower costs.Cost factors other than construction costs were left unchanged from 2020.Figure 1 Approach to 2030 Onshore Wind Power Cost Reduction Forecasts Source Item Recent costs 2030 costs(reduction rate 10-47%)IRENA Future of wind,2019 13P Total installation

14、costs*Average or average range 1,497 USD/kW(2018)800-1,350 USD/kW(REmap Case 2030 costs)Regular report Connection costs excluded from investment costs 347,000 yen/kW(2018-2020)184,000-312,000 yen/kW(Construction cost estimate)Source:Power Generation Cost Verification Working Group(2021)Note:“Regular

15、 report”means actual domestic cost data of onshore wind power plants reported by wind power generators under the obligation required by Act on Special Measures Concerning Procurement of Electricity from Renewable Energy Sources by Electricity Utilities(Renewable Energy Special Measures Act).1 Accord

16、ing to Japan Wind Power Association(JWPA),accumulated installed capacity of wind power in Japan was 4.58GW at the end of 2021.（https:/jwpa.jp/information/6225/）5 The method used by the working group to consider costs is one possible approach,but given the gap between costs internationally and costs

17、in Japan,taking only the rate of reduction as proportional is an approach that requires further verification.The assumptions,too,for capacity factor are“limited suitable sites”and“unchanged from 2020 in light of recent years trends,”but in terms of a method for 2030 capacity factor assumptions,this

18、methodology seems to lack technical basis.Given this background,it is important that we appropriately assess technical trends from recent years and evaluate future cost forecasts while better grounding them technologically and economically.By assessing costs based on technological and economic evide

19、nce,it becomes possible to gain insights for reducing onshore wind power costs in Japan.Based on this recognition of the problem,this study considers possibilities for reducing onshore wind power costs in Japan by accurately grasping the technologies and economy of onshore wind power plants which ha

20、ve started operation since 2016.The first chapter summarizes the results of a survey of technologies.The second chapter summaries the results of an investigation and analysis of costs.The study concludes with a summary of analysis results and discusses the potential for cost reductions.Scope and met

21、hodology of technology and cost considerations The scope of cost considerations focuses on investment costs and capacity factors.Investment costs are divided broadly into turbine costs(e.g.,nacelle,tower,blades)2,construction costs,electric work costs,grid connection costs,and development costs.This

22、 study excludes development costs like wind condition surveys and environmental assessments,and focuses specifically on installation costs,performing detailed analysis of turbine costs,construction costs,electrical work costs,and grid connection costs.In addition,while it is important to consider op

23、eration and maintenance costs,many of the wind power plants installed after the introduction of the feed-in tariff(FiT)scheme have not been operating long,so it is difficult to acquire adequate data.As a consequence,these costs were excluded from the scope of the survey.In terms of the methodology u

24、sed for technology and cost considerations,a questionnaire was administered to wind power operators,information collected on onshore wind turbine technologies and costs,and statistical analysis performed based on the data.The scope of wind power plants was commercial plants of 1.5 MW or higher launc

25、hed in 2016-2021.The collected data is broadly divided into five categories:1)information on the time from the plants FiT certification to the start of construction and the start of operations,2)basic plant information(installed capacity,turbine capacity,number of turbines,turbine technical data),3)

26、information on direct construction costs,4)information on construction(foundation,site preparations,facility installation,electrical work,transmission lines),and 5)capacity factors.2 When referring to power sources in general,the term wind power is used.When referring to wind turbines(including nace

27、lles,towers,etc.)and the cost,wind turbine and wind turbine cost are used.And when referring to the entire facility including electrical equipment,etc.in addition to wind turbines,wind power plant is used.When indicating that the facility is limited to onshore use,onshore shall be appended.6 2 Onsho

28、re wind power technology trends in Japan 2.1 Summary of data The data sample covers 32 power plants with total installed capacity of 646 MW and 266 turbines(Figure 2).This represents around 40%of the installed capacity of power plants built in Japan between 2016 and 2021.The average plant size is 20

29、 MW.The average plant size around the world differs with the region,but according to Wang(2021),it is 268 MW in Central and South America,218 MW in North America,and 24 MW in Western Europe(2019-21).The average plant size in Japan is at the same level as Western Europe.Figure 2 Summary of Power Plan

30、t Data Launch year 2016-17 2018-19 2020-21 Total Number of plants 7 16 9 32 Installed capacity(MW)155 243 249 646 (Ref:Newly installed capacity in Japan MW)*412 523 727*1,662 Number of turbines 77 101 88 266 Avg.turbine capacity*(MW/turbine)2.0 2.4 2.8 2.4 Avg.plant size(MW)22 15 28 20 *Newly instal

31、led capacity in Japan:numbers calculated based on the data of Renewable Energy Promotion Law.Data of 2021 only referred to JWPA(https:/jwpa.jp/information/6225/）*Average turbine capacity=Total installed capacity/Number of turbines The following shows the geographical distribution of the sample.As sh

32、own in Figure 3,compared to the statistical population(all plants of 20 kW of higher installed under FiT),the sample is slightly less in Hokkaido and larger in western Japan.On the other hand,the distribution in Tohoku closely mirrors the population.Figure 3 Regional Distribution of Population and S

33、ample Note:The eight regions are based on prefectural divisions and differ from general electricity transmission and distribution areas.0%10%20%30%40%50%60%70%80%90%100%Statistical populationSampleKyushuShikokuChugokuKinkiChubuKantoTohokuHokkaido7 2.2 Trends in onshore turbine technologies 2.2.1 Tur

34、bine capacity This section organizes trends in onshore turbine technologies in Japan based on the sample data.First of all,as shown in Figure 2,average turbine capacity has been increasing.It was 2.0 MW per turbine in 2016-17,and this increased to 2.8 MW in 2020-21.Figure 4 shows the distribution of

35、 single onshore turbine capacity based on per-plant averages.In 2016-17,turbines of 2 MW or lower were the mainstream,but large turbines have been installed in quick succession so that as of 2020-21 turbines over 3 MW have become the mainstream.Figure 4 Single OnshoreTurbine Capacity Distribution(Pl

36、ant Averages)2.2.2 Hub height and rotor diameter As turbine capacitys have increased,hub heights and rotor diameters have also increased.The average hub height was 77.3 m in 2016-17,but in 2020-21 it was 82.4 m,advancing by approximately 5 m(Figure 5).At their highest,hub heights are over 90 m.The a

37、verage rotor diameter was 85.7 m in 2016-17,but it has grown to over 100 m in 2020-21(Figure 6).The hub height was usually designed to keep the rotor above a certain minimum ground clearance.Relation between average hub height and average rotor diameters for each year can be found that“Hub height=ro

38、tor diameter/2+(3234)”.These increases in hub heights and rotor diameters have helped increase the amount of electricity generated from each turbine.0%10%20%30%40%50%60%70%80%90%100%2016/172018/192020/213.0MW2.53.0MW2.02.5MW2.0MW8 Figure 5 Average Hub Height(Plant Averages)Figure 6 Average Rotor Dia

39、meter(Plant Averages)2.2.3 Specific power On the other hand,the fact that the capacity per turbine is increasing does not necessarily indicate that the per-turbine capacity factor is also increasing,but we should looke at specific power(W/),which is capacity per square-meter of swept area.Theoretica

40、lly,wind power capacity(W)is proportional to the cube of wind speed and proportional to the swept area of the rotor.Therefore,for the same wind speed,the smaller the specific power(W/m2),the greater the wind power capacity(W)and the greater the capacity factor.Generally,in areas with low wind speeds

41、,turbines with low specific power have been used to increase the electricity generated.For this reason,to assess trends in onshore wind power technologies,it is necessary to also consider specific power figures.Trends in average specific power in the sample obtained in this study are shown in Figure

42、 7.There is a slight downtrend,and this,in theory,is helping to raise capacity factors.However,average specific power has decreased dramatically in the world.A slightly old data shows that specific power in the EU was already 322 W/in 2016 77.380.682.4007080902016/172018/192020/21m85.793.

43、0100.30204060801001202016/172018/192020/21m9(IEA Wind,2019).In Germany,specific power was 317W/(IEA Wind,2019),and decreased to 286W/in 20213.In 2021,the average rotor diameter in Germany was 133m which is significantly longer than 100m,the average in Japan.In the US,average specific power in 2020 w

44、as 223 W/m2,which is significantly lower than Japan and Germany(DOE,2021).The reason average specific power for onshore turbines is lower in the US is the contribution being made by the use of blades with large rotor diameters for a small single unit capacity.The average rotor diameter in the US is

45、124.8 m,around 25 m longer than turbines in Japan(DOE,2021).Figure 7 Trends in Specific Power 2.2.4 Turbine Types Based on IEC Wind Turbine Standards(2005)IEC(International Electrotechnical Commission)is an organization that formulates international standards in the field of electrical and electroni

46、c technology and the design requirements for wind power generation are specified in IEC61400-1.Wind turbine standards based on the international IEC 61400-14,as shown in Figure 8.differ with differences in wind conditions and are divided into four classes,I,II,III,and S.Standard wind turbine standar

47、d are classified into three classes,I,II,and III,according to annual average wind speed,reference wind speed,and turbulence intensity.There is also a class S,which designates turbines not categorized into any of the three standard classes.“Class S designates not only turbines with high standard wind

48、 velocities specified by the designer but also potentially refers to those with low velocities and all turbines with design specifications that differ from standard,including for turbulence intensity,wind speed frequency distribution,operating temperature,and air density”(NEDO,2008),Appendix A-3).Ac

49、cording to Wang(2021),wind turbines classified in Class and Class have been mainly used in the world in 2016-2021.3 Calculated by the average data of onshore wind power in Germany based on Deutsche WindGuard GmbH(2022)4 In 2019,IEC61400-1 is being revised to its fourth edition,in which a new criteri

50、on for reference wind speeds,Class T,which considers tropical cyclones such as typhoons and high turbulence.As a result,wind turbine manufacturers have been developing wind turbines that comply with this new standard.However,all wind turbines surveyed in this study were constructed before 2019,and i

51、t is believed that the wind turbines that comply with this new standard are not included in this study.397 384 378 05003003504004502016/172018/192020/21W/m210 Figure 8 IEC 61400-1(2005)Wind Turbine Standard Wind Conditions Source:NEDO(2008),Appendix A-3 The turbine types in the sample dat

52、a are organized based on the categories of the IEC 61400-1 standard.As shown in Figure 9,most installed onshore turbines in Japan are IEC class II turbines,followed by class S and class I.While the average annual wind speeds in Japan are lower than the rest of the world,it is expected that Class I o

53、r Class S wind turbines are required in some areas due to high turbulence intensity caused by strong winds from typhoons and the countrys topography.However,this study reveals that Class II turbines,widely adopted in other countries,also account for the majority in Japan.On the other hand,Class III

54、turbines,also adopted worldwide,are rarely used in Japan.It can be considered that Class III turbines cannot cope with the temporary strong winds caused by typhoons.Figure 9 Distribution by IEC Standard 2.3 Capacity factor Capacity factors were compiled for the past year,and,as shown in Figure 10,th

55、e nationwide average was 27%.Based on data from the governments Procurement Price Calculation Committee,the average capacity factor from June 2020 to May 2021 was 26.0-27.3%(ANRE,2021),so the 27%figure is in line with the governments data.Looking at capacity factors by region,Tohoku and Hokkaido is

56、higher than the nationwide average and lower in other regions,suggesting that geographically wind conditions are good in northern Japan.0%10%20%30%40%50%60%70%80%90%100%Eastern JapanWestern JapanNationwideS11 Figure 10 Average Capacity Factor by Region Note:Average capacity factor is calculated as t

57、he ratio of total estimated electricity generated by each power plant to the installed capacity of each plant.Capacity factor is impacted not only by the wind condition of the site but also by hub height and specific power.Based on this fact,we statistically analyzed the relative impact of these mul

58、tiple factors on an increased capacity factor.Here,extension-type quantification I is used for multivariate analysis5,to analyze differences in location by category.Capacity factor is the objective variable,and there are three explanatory variables:region,hub height,and specific power.The analysis r

59、esults of extension-type quantification I are shown in Figure 11.The coefficient of determination is 0.368,so analysis precision is not necessarily good.This is because the categories are roughly divided into just four regions,which does not accurately reflect wind condition at the power plant sites

60、.Looking at category scores6 by region,Hokkaidos score is extremely high at 3.4 points.This means that plants sited in Hokkaido have a capacity factor 3.4 points higher than the average.Regarding hub heights(m),when the height goes up by 1 m,capacity factor goes up by 0.6 points.Specific power,theor

61、etically,should be negative,but it is slightly positive,so the low precision of the analysis is a problem.5 Extension-type quantification I is one of the methods to derive a forecast model equation,predict the objective variable,and elucidate the factors that have an important influence on that pred

62、iction,and allows both quantitative and qualitative data to be applied to the forecast equation for the explanatory variables.(Institute of Statistical Analyses,Inc.)6 Also called categorical data,this is a quantitative representation of the extent to which each categorical item influences the value

63、 of the objective variable.27%30%21%20%25%27%0%5%10%15%20%25%30%35%HokkaidoTohokuChubuKinkiChugokuShikokuKyushuNationwide12 Figure 11 Analysis of Factors Affecting Capacity Factor 3.4 0.9 0.0-3.4 0.6 0.0-4-3-2-101234HokkaidoTohokuKyushuOtherRegionHub heightSpecific powerCategory scores(%)13 3 Trends

64、 in Onshore Wind Power Costs in Japan Based on the analysis of technological trends in the previous chapter,we analyze onshore wind power costs in Japan in this chapter,based on the cost data that was obtained.This study focuses on installation costs.Other costs are excluded from the scope of analys

65、is.3.1 Installation costs Average installation costs have been gradually coming down,decreasing from 327,000 yen/kW(2016-17)to 285,000 yen/kW(2020-21)(Figure 12).Three cost areas have been declining:wind turbine costs,electrical work costs,and battery costs.At the same time,transportation costs(dome

66、stic)and foundation and site preparation costs are increasing.Transportation costs have increased from 12,000 yen/kW to 22,000 yen/kW.However,this is due to some projects being delayed by the COVID-19 pandemic and unanticipated costs being incurred from unavoidable situations such as transport vehic

67、les standing by or being re-dispatched.Excluding these outliers,transportation costs are nearly unchanged.Figure 12 Average Installation Costs Source:BNEF 2021 refers to Wang(2021).Price of wind turbines contracted in the second half of 2020.05001,0001,5002,0002,5003,0003,5002016/172018/192020/21BNE

68、F 2021USD/kWTurbineTransport to siteFoundationsAccess roadsInstallationCabling and InterconnectionSubstationSurcharge by Grid operatorsGrid reinforcement chargeBattery costs14 When compared to average installation costs for onshore wind power globally during the same period(BNEF 2021),which are 149,

69、000 yen/kW,Japans installation costs are fairly high(Figure 12).Looking at the breakdown,some costs differ greatly from BNEF 2021 levels and others are nearly the same.The costs equivalent to global levels are transportation costs,road development costs,and facility installation costs.The costs that

70、 differ substantially from BNEF 2021 levels are 1)turbine costs,2)foundation and site preparation costs,and 3)electrical work and transmission infrastructure costs(including electrical work,construction work contributions,upper grid enhancements,and battery storage costs).The following considers the

71、 above three cost categories in detail.3.2 Wind turbine costs Wind turbine costs account for the largest proportion of installation costs,so they are an important factor for cost analysis.Average turbine costs per kilowatt have fallen from 175,000 yen/kW(2016-17)to 148,000 yen/kW(2020-21)in Japan.Th

72、e median has fallen from 145,000 yen/kW to 131,000 yen/kW(Figure 13).Figure 13 Wind Turbine Costs(Quartiles)Note:The median is shown with;the upper-lower range is 25%and 75%.At the same time,as shown in Figure 12,there is a major difference between turbine costs in Japan and turbine costs internatio

73、nally.However,BNEF 2021 figures in Figure 12 refer to turbine prices contracted in the second half of 2020,and in some cases they are not on the same timeline as costs in Japan,which are shown based on the launch year.In order therefore to compare costs on the same timeline,for turbine costs based o

74、n the construction-start year(at site delivery time),the results of this survey and overseas data were compared(Figure 14).As a result,there was a cost difference of around 50,000 yen/kW.Around 30%of power plants adopted wind turbines supplied by relatively expensive turbine manufacturers.This cost

75、difference was hardly reduced even if they were excluded.14.515.213.41618202016/172018/192020/2110,000 yen/kW15 Figure 14 Turbine Costs:Comparison of Japan and International Levels Source:BNEF applies figures in Wang(2021).Exchange rates use the average rate for that year.Note:internation

76、al transportation costs are included in turbine costs data of both Japan and BNEF.As mentioned above,Japans wind power plants are nearly the same size as Europes,but differ greatly in size from the US.To determine whether this difference in plant size has a major impact on the cost of the wind turbi

77、nes that are procured,reference was again made to BNEF data(Figure 15).Looking at Figure 15,wind power plants of 11-30 MW(the average plant size in Japan is 20 MW)procure turbines at costs that are equivalent to other sized plants,particularly large-scale plants.It is hard,therefore,to conclude that

78、 differences in power plant size in the world is likely to be the reason for the high cost of wind turbines in Japan.With regard to the turbines themselves,even if there are some differences in specifications(incl.IEC standards),it is unlikely that this would produce large differences in real costs

79、between Japan and the rest of the world.Figure 15 Turbine Cost by Plant Size(at Site Delivery Time)Source:Created from Wang(2021).053/00,000 yen/kWJapanBNEF02004006008001,0001,2001,4002013/01720182019USD/kW10MW11-30MW31-50MW51-100MW101MW+16 Next,we analyze

80、 factors thought to impact turbine costs(per kilowatt)using extension-type quantification I.In this analysis,the objective variable is turbine cost,and the explanatory variables are construction-start year,contract type,IEC standard,single turbine capacity,number of turbines(at the plant),and hub he

81、ight(Figure 16).The analysis resulted in a coefficient of determination of 0.537,which is medium precision.Excluding differences caused by the construction-start year,the results suggest that increasing single turbine capacity could contribute to reducing turbine costs.Differences in contract type c

82、ould also be an important factor.Procuring turbines with methods other than via EPC contract(through BOP7 or separate engagement8)has the potential to reduce costs.Further,increasing the number of turbines at the plant is also a cost-reduction factor.On the other hand,advancing hub heights is potent

83、ially a cost-increase factor.Figure 16 Analysis of Turbine Cost Factors 7 BOP contract type stands for Balance of Plant contract,in which all the construction work is ordered to a general contractor,except for wind turbine procurement.8 Separate engagement contract is a method in which the power pro

84、ducer supervises every process from wind turbine procurement to construction work and contracts directly with each individual construction company,rather than making an order in a bundle with an EPC contractor for everything.-3.36 4.80 0.75-0.79-1.43 1.78 1.64-1.86-1.23 0.86-0.81-6.51-0.18 0.42-8-6-

85、4-202462013/14 200182019EPCOthersTurbineoutputNumberofturbinesHubheightConstruction-start yearContractIECTurbineoutputNumberofturbinesHubheightCategory scores(10,000 yen/kW)17 3.3 Foundation and site preparation costs Average foundation and site preparation costs have increased from 34,00

86、0 yen/kW in 2016-17 to 43,000 yen/kW in 2020-21.The median has also increased slightly,from 30,000 yen/kW to 35,000 yen/kW.Figure 17 Foundation and Site Preparation Costs(Quartiles)Foundation and site preparation costs could be impacted by the site topography and construction material costs.Firstly,

87、the study looked at topography and construction details,factors that could correlate with foundation and site preparation costs.Figure 18 shows the average site prep soil volume per turbine,pile foundation rate,and average single turbine construction costs for each topographical type.Each of these i

88、tems is related to foundation and site preparation costs.Topography is categorized into four types based on topographical data for wind power plant sites in the Environmental Impact Assessment Database System9 maintained by the Ministry of the Environment in reference to the 1:200,000 topographical

89、map prepared based on the Fundamental Land Classification Survey administered by the Ministry of Land,Infrastructure,Transport and Tourism.Site prep soil volume is related to costs for preparing the yard.Also,classified broadly,there are two types of foundations,direct and pile,and even the same pla

90、nt may use both types depending on ground conditions;foundation and site preparation costs also vary.Figure 18 Construction Details and Unit Costs by Topography Type Topography type Number of plants Avg.site prep soil volume per turbine(1,000 m3)Avg.pile foundation rate Avg.single turbine constructi

91、on costs(million yen/turbine)Lowlands 11 2.3 90%161 Tablelands 5 2.1 67%100 Hills 4 8.1 83%65 Mountains 13 5.3 48%86 Note:Pile foundation rate:Number of turbines with pile foundations/Number of turbines at the plant 9 Ministry of the Environment,“Environmental Impact Assessment Database System”(http

92、s:/www2.env.go.jp/eiadb/ebidbs/)3.03.33.501234562016/172018/192020/2110,000 yen/kW18 Based on topography type,the following characteristics can be found.First of all,with regard to site prep soil volume per turbine,soil volume is low on plains and tablelands,around 2,000 m3 per turbine,but in hills

93、and mountains,where the terrain is complex,soil volume is over 5,000 m3 per turbine.As for the foundation construction method,pile foundations are generally used when plants are installed on soft ground.Because this cost depends on ground conditions at the site,it is difficult to find clear trends b

94、ased on the topography type,but pile foundations are often used in lowlands and tablelands.On the other hand,in mountains,the direct foundation rate is relatively high compared to other topography types.Average foundation engineering costs per single turbine are high in lowlands and tablelands and r

95、elatively low in mountains and hills.The result runs contrary to the normal assumption that construction costs are high in mountainous areas.Next,concrete is one of the construction materials that would impact the costs,so the study looked at the price of ready-mix concrete(RMC)(Figure 19).Using pri

96、ce indices by city for each year to calculate average RMC prices,in Tohoku(Sendai),the price has been coming down since peaking in FY2014-15,and it has been increasing in most other regions.Figure 19 Average Ready-Mix Concrete Price Estimates by City(yen/m3)Sapporo Sendai Tokyo Niigata Nagoya Osaka

97、Hiroshima Takamatsu Fukuoka FY2013 10,962 13,696 12,522 11,801 9,101 12,072 14,115 8,127 10,562 FY2014 12,363 14,048 12,814 12,339 10,256 12,072 14,115 8,187 10,900 FY2015 12,400 14,048 13,279 12,527 11,221 12,072 14,796 8,457 10,900 FY2016 12,896 14,020 13,279 12,527 11,098 13,171 14,929 10,867 10,

98、137 FY2017 13,243 13,696 13,412 12,364 10,806 15,609 14,929 12,584 9,374 FY2018 13,243 13,444 13,824 8,969 10,930 16,116 14,929 12,584 11,412 FY2019 13,243 12,938 14,195 8,519 11,300 18,314 15,698 13,878 13,450 FY2020 13,243 12,390 14,408 10,247 11,300 19,400 15,950 14,800 13,450 Note:Average RMC pr

99、ices by city are calculated for each fiscal year using RMC prices listed in“Primary Material Markets and Price Trends”on Kensetsu Plaza,a general construction portal site,and price indices by city by fiscal year published by the Economic Research Association.As shown above,foundation engineering cos

100、ts are tied to various factors.Statistical analysis therefore was performed to determine the extent to which the multiple factors affect these costs.This method used was extension-type quantification I.The objective variable is foundation engineering costs(total)and the explanatory variables are fou

101、ndation type,site prep soil volume,RMC prices,and basic design contractor10.The results of extension-type quantification I analysis are shown in Figure 20.The coefficient of determination is 0.648,so analysis precision is medium.From this analysis,it can be seen that foundation type has a large effe

102、ct on costs.The category scores specifically indicates that pile foundations are approximately 11 million yen per turbine more costly than direct foundations(Figure 20).In Figure 18,foundation engineering costs are higher in lowlands,possibly due to the fact that in lowlands,the solid ground is seve

103、ral tens of meters below ground level,and 10 Basic design contractor has been added as an explanatory variable because in correlation analysis the correlation ratio exceeded 0.1.19 therefore,costly pile foundations are often used.Also,it was found that both RMC prices and site prep soil volume have

104、an impact on costs.Moreover,differences in the basic design contractor also potentially affect foundation engineering costs.Though it is unclear how differences in the contractor affect basic design,it is possible that in the basic design it is important to consider elements such as the optimal layo

105、ut of turbines in terms of the impact of these on foundation engineering costs.Figure 20 Analysis of Factors Affecting(Total)Civil Engineering Costs 3.4 Electrical work and transmission infrastructure costs As shown in Figure 12,electrical work costs and transmission infrastructure costs are extreme

106、ly high compared to overseas.These costs include installation costs for transformers and other electrical equipment,onsite cable installation costs,and installation costs for power lines from the plant to the connection point(offsite connection lines).Moreover,there are also surcharge required to pa

107、y to the transmission and distribution system operator when connecting to the grid.In addition,when a connection request is made by power producer,if the transmission and distribution system operator determines there is no available capacity on the upper grid,the producer was also charged for upper

108、grid enhancement costs11.Separate from this,some transmission and distribution operators required wind 11 This system was changed with the“Guidelines on Grid Enhancements from Power Facility Installation and the Cost Burden,etc.of Operations”formulated in 2015,and regarding core intraregional grids

109、in the upper two voltage categories,in terms of the general cost burden,as a basic principle,power producers bear no burden except in cases in which significant enhancement costs are incurred 82 92 5 210 26(202)144-250-200-150-0200250In-houseEPCOtherDirectfoundationturbinesPile foundat

110、ionturbinesSite prep soilvolume(thousand m3)Basic designRMC price(thousandyen/m3)Category scores(million yen)20 power producers to take measures for frequency changes,and for this they required that battery storages be installed for some wind power plant connections.For example,in FY2008 and FY2010,

111、before the Act on Special Measures Concerning Procurement of Electricity from Renewable Energy Sources by Electricity Utilities(Renewable Energy Special Measures Act)was introduced,Tohoku Electric made offers to purchase electricity from wind power plants on the condition that battery storages were

112、installed(Tohoku Electric Power Co.,Inc.,2008;2010).The survey sample included a number of plants that responded to this offer.For these plants,battery storage installation costs are included.Figure 21 Trends in Average Electricity/Transmission Related Costs Figure 21 shows the average cost per kilo

113、watt based on the survey sample.In terms of trends,average battery costs were 24,000 yen/kW in 2016-17,but costs dropped sharply and were zero in 2020-21.This means that there were no longer connections to the grid by power plants that had been required to install battery storages prior to the Renew

114、able Energy Special Measures Act taking effect,as discussed above.As mentioned,battery storages were only installed at certain power plants,so it is difficult to grasp the actual situation looking at average costs alone.Taking only plants that have battery storages,battery costs exceeded 60,000 yen/

115、kW in all cases,significantly raising installation costs.In the other cost category,electrical work costs registered a large decline in 2018-19.Regarding upper grid enhancement costs,within the sample,there was one plant that had these costs.It was a medium-sized plant with total capacity between 7.

116、5 MW and less than 15 MW,but it bore upper grid enhancement costs of more than 200 million yen.Other costs(transmission infrastructure costs,construction work contributions)are flat and have not changed.(when the maximum general cost burden 20,000 yen/kW for onshore wind power is exceeded)(Agency fo

117、r Natural Resources and Energy,2015).0.00.51.01.52.02.53.03.54.02016/172018/192020/2110,000 yen/kWCabling and InterconnectionSubstationSurcharge by Grid operatorsGrid reinforcement chargeBattery costs21 Transmission infrastructure costs are installation costs for onsite power lines and offsite conne

118、ction lines.These costs vary with the voltage level and line length.The study used the extension-type quantification I method to analyze the relationship between these related factors and(total)transmission costs.The objective variable is(total)transmission costs,and the explanatory variables are ty

119、pe of offsite connection lines and onsite power lines,distance,voltage,and contract type.As a result,the coefficient of determination is 0.784,so precision is high.As shown in Figure 22,the length of offsite connection lines,particularly underground lines,is a factor that increases costs.Underground

120、 offsite connection lines are more costly than even overhead lines,which are 30 million yen per kilometer.It was found that higher-voltage offsite connection lines lead to increased transmission infrastructure costs.However,transmission at high voltage reduces transmission loss,so it is important th

121、at cost increases are balanced out by transmission efficiency.Another noteworthy finding was differences in transmission infrastructure costs depending on the contract type.That is to say,separate engagement has the potential to reduce transmission infrastructure costs.Figure 22 Analysis of Factors

122、Affecting(Total)Transmission Infrastructure Costs 95 130 24(60)(19)(35)214(428)-500-400-300-300Overhead line distance(km)Underground line distance(km)Voltage(kV)Overhead line distance(km)Underground line distance(km)Voltage(kV)EPC/BOP contractSeparate engagementOffsite(connection)lines

123、Onsite linesContract typeCategory scores(million yen)22 4 Conclusion:Summary of Analysis Results and the Potential for Reducing Onshore Wind Power Costs in Japan This study analyzed technology trends and costs for onshore wind power in Japan over the six years from 2016 to 2021.Below is a summary of

124、 the findings gained from this study which offers insights into the potential of reducing onshore wind power costs.1)Steady increase in wind turbine size was observed in Japan.From 2016 to 2021,the average turbine capacity increased from 2.0 MW to 2.8 MW.In particular,the output of most turbines ins

125、talled in 2020-21 were over 3.0 MW.2)Increase in turbine capacity is very much interconnected with advancments in hub heights and reducing specific power.Both of these serve to increase the capacity factor.These factors are also listed in JWPA(2019)s report on Cost Competitiveness Task Force,and is

126、considered as one of the technologies that will drive costs down in wind power generation in Japan.3)On the other hand,JWPA(2019)also states that technological progress,such as growth in turbine size“is projected to increase construction costs even if technological innovations in nacelles,towers,and

127、 foundation structures are anticipated”and there are concerns that turbine,foundation and site preparation costs will rise.The results of this study however confirmed that although increasing hub heights was a cost-adding factor,increasing turbine capacity had the potential to reduce turbine costs(p

128、er kilowatt).4)Regarding foundation and site preparation costs,no evidence was found that increasing turbine capacity causes an increases in costs.The results showed that pile foundation costs compared to direct foundations may have an influence in pushing up costs and that the complexitiy of the te

129、rraine was not the sole factor affecting costs.5)The study also revealed that the voltage of the offsite connection line and the distance of the underground line were important factors that affected transmission infrastructure costs.Taking this into account when installing power lines will be worthw

130、hile to consider.6)Onshore wind power installation costs are greatly affected by grid connection and usage rules.Until now,power producers had to bear specific costs such as upper grid enhancement costs and in certain regions,storage battery installation costs due to regualations layed by the genera

131、l electric utilities.These costs became a significant burden on the wind power producers.As of 2022,these rules that have caused individual power producers to excessively bear costs related to infrastructure development and grid stabilization,are being banned,and consequently,a decline in installati

132、on costs are already observed and expected to continue in the future.7)Differences in contract type had an impact on several cost categories to a greater or lesser degree.The study showed that wind turbine costs could be reduced through direct procurement(contract type referred to as“other than EPC”

133、)and transmission infrastructure costs could be reduced by separate engagement.The above findings reported here is expected to serve as a basis for examining future costs in wind power generation.23 In this study,a clear upward trend in wind turbine size was observed,and its impact on costs was empi

134、rically demonstrated.These findings highlight the following:When making projections for 2030 generation costs,it is necessary to foresee the effects of technology advancements and evaluate the impact it will have on wind turbine costs and capacity factors.Taking such considerations into account will

135、 help minimize uncertainties when forecasting future gereration costs.Secondly,the governments Power Generation Cost Verification Working Group(2021)assumes that only wind turbine costs will converge with international prices and that other costs will remain unchanged.This assumption is rather too s

136、implified and the perspective that cost efficiency,which is expected to improve on the whole,will also contribute in cost reductions,is missing.In fact,the present study demonstrated that there were differences in costs depending on basic design contractor and contract types.It is possible to assume

137、 that cost efficiency will accelerate as domestic power producers become more skilled.On the other hand,there were several issues that requires further investigation.While it was confirmed once again that major costs,such as wind turbine costs,are considerably higher in Japan compared to the rest of

138、 the world,the study was not able to identfy why there was an approximately 50,000 yen per kilowatt difference in turbine costs between Japan and other countries.Another result that ran counter to conventional wisdoms was that the cost per turbine turned out to be higher in lowland areas than in the

139、 mountainous areas.Further research will be needed to find out the factors lying behind this.24 5 References Japan Wind Power Association Cost Competitiveness Task Force(JWPA)(2019),Report of the JWPA Cost Competitiveness Task Force:Toward Achievement of Grid Parity Agency for Natural Resources and

140、Energy(2015),Guidelines on Grid Enhancements from Power Facility Installation and the Cost Burden,etc.of Operations Agency for Natural Resources and Energy(2021),On Wind Power,Document 3,73rd Meeting of Procurement Price Calculation Committee Power Generation Cost Verification Working Group(2015),Re

141、port to the Subcommittee on Long-term Energy Supply-demand Outlook on Long-term Forecast of Energy Supply and Demand Power Generation Cost Verification Working Group(2021),On Power Generation Cost Verification New Energy and Industrial Technology Development Organization(NEDO)(2008),Guidelines for D

142、evelopment of Wind Power Generation in Japan:Typhoon and Turbulence Measures Edition Tohoku Electric Power Co.,Inc.(2008),Summary of FY2008 Wind Power Generation Offer and Other Related Matters Tohoku Electric Power Co.,Inc.(2010),Summary of FY2010 Wind Power Generation Offer and Other Related Matte

143、rs Deutsche WindGuard GmbH（2022）Status of Onshore Wind Energy Development in Germany-Year 2021.IEA Wind TCP Task 26:IEA Wind（2019）Cost of Wind Energy Phase 3 Final Technical Report.Wang,Leo(2021),1H 2021 Wind Turbine Price Index(WTPI),BloombergNEF.U.S.Department of Energy:DOE(2021)Land-Based Wind Market Report:2021 Edition.inforenewable-ei.orgwww.renewable-ei.org/enCost and Technology Trends for Onshore Wind Power in JapanRenewable Energy Institute11F KDX Toranomon 1-Chome Bldg.,1-10-5 Toranomon,Minato-ku,Tokyo 105-0001TEL：03-6866-1020May 2022