Real-world car emission estimations a more accurate approach 实际排放差异分析 一个更精准的方法 E4tech September 2016 Dave.OudeNijeweme@E4tech.com Strategic thinking in sustainable energy
内容 What are the issues? What did we do? What did we find? How can we improve? Conclusions & recommendations 2
What are the issues? Strategic thinking in sustainable energy
Significant transport improvements are required to meet the Paris Agreement and improve urban air quality 为满足巴黎协议及提升城市空气质量, 交通亟需改善 Transport GHG contributions - IEA Global London annual NO 2 concentration Source: International Energy Agency Local https://citygeographics.org/2015/10/20/what-can-the-nextmayor-do-to-tackle-londons-hazardous-air-pollution/ 4
Real world deviation in both fuel economy and pollution performance 真实世界的差异同时存在于燃料经济性及排放 CO 2 emissions gap - EU Gap 油耗 NO x emissions gap - EU Source:http://www.theicct.org/sites/default/files/Fact% 20sheet_FromLabToRoad_2015.pdf Gap 污染物 Source: E4tech analysis & ICCT PEMS study diesel cars 2014 factsheet 5
What did we do? Strategic thinking in sustainable energy
实际排放估算通常采用自下而上方法, 我们应用更精准的自上而下的方法 典型 bottom-up vs. E4tech top-down Car registration data HBEFA 1 UK travel Survey A B C X Vehicle x fleet A B C X Emission x factors A B C X Mileage = CO 2, CO, HC, NOx, PM Fleet emissions Fuel consumed # vehicles x Ave. mileage = CO 2 UK energy statistics Car registration data Yearly test database 1 HBEFA = the European Handbook for Emissions factors x A B C X = Input source & quality indicator. Green = reliable, Amber = OK, Red = unreliable = Vehicle fleet split by type of vehicles or emission levels 7
What did we find? Strategic thinking in sustainable energy
New car fleet CO2 emissions (g/km) 结果表明真实 CO2 排放差异比 ICCT 等得到结果更大 28% The gap is even larger than expected And has always been very large Top-down Bottom-up Tested / claimed Year of registration 9
Survey Why? 比较 2013 年车辆出行公里数 :MOT* 数据 V.S. 调查数据 (DfT) Comparing the travel survey data with the MOT database in 2013 shows that the MOT* value is 3.6% higher than the UK s National Travel Survey This explains some of the difference, but certainly not all of it *MOT= Annual roadworthiness test 10
HBEFA 问题一定在于所用的排放因子 Overlaying HBEFA average fleet with UK average fleet Indication that emission factors are optimistic 11
汽油车队 真实 CO 2 排放比官方结果高出 8Mt CO 2 (in 2013) 官方 结果 : New car data from OEMs * number of vehicles * average mileage 真实 结果 : Total gasoline consumption / total number of vehicles and average mileage The gap was found to be 25.9% for gasoline cars which is equivalent to 8 Million Tonnes of CO 2 in the UK in 2013 Extending this logic it is reasonable to expect that this also applies to: Other vehicles in the UK All vehicles in Europe Pollutant emissions for all vehicles in Europe 12
What can be improved? Strategic thinking in sustainable energy
由 E4tech 及 icet 联合开发的 CUTEC 排放计算工具为决策者提供参考依据 China Urban Transport Emissions Calculator is split into 3 layers: 1. High-level user input and output This tab is for a user who does not require a detailed understanding of the interdependencies between detailed inputs but wants to compare various pre-prescribed scenarios. Includes an input dashboard and key graphical outputs. 2. Advanced user input Tabs dedicated to prescribing various scenarios and all other detailed inputs. Requires advanced understanding of how different policies affect vehicle stock and vehicle-kilometres travelled (VKT) in a city. There are two separate tabs for setting the baseline and for the scenario. 3. Mechanics of the tool The tabs that follow user inputs form the back-end of the calculator where all calculations are taking place. They do not require any user input and it is not recommended to change the formulas within. 14
图表界面展示关键的输入及输出 15
比较不同来源的排放因子, 表明 HBEFA 的排放因子需进一步改进 Having piloted CUTEC for the city of Shenzhen it became apparent that HBEFA emission factors are fairly optimistic See below comparison of the HBEFA pollutant emission factors with the EU emission limits under New European Drive Cycle (NECD) type conditions HBEFA EU Emission limits 16
结论 & 建议 Strategic thinking in sustainable energy
结论 & 建议 结论 UK 汽油车的 CO 2 排放低估了约 28% 标准的排放因子为主要原因 污染物的排放因子同样并不准确 建议 车队 CO 2 排放应同时采用 topdown 和 bottom-up 方法来确保精准度 排放因子亟待优化 应用更多工具如 CUTEC 来协助政策制定 导致 模型明显低估了车辆 CO 2 及污染物排放 被误导的政策 18
E4tech strategic thinking in sustainable energy For more information please visit our website: www.e4tech.com Or contact us in London or Lausanne: E4tech (UK) Ltd 83, Victoria Street London SW1H 0HW United Kingdom +44 (0)20 3008 6140 enquiries@e4tech.co.uk E4tech Sàrl Av. Juste-Olivier 2 1006 Lausanne Switzerland +41 (0)21 331 15 70 enquiries@e4tech.ch 19