Subject: Proposal for E75 reference fuel specifications for Type 6 test. Contributors: Motor Vehicles Emission Group (MVEG) members

Transcription

1 EUROPEAN COMMISSION JOINT RESEARCH CENTRE Institute for Environment and Sustainability Transport and Air Quality Unit Ispra, 22 February 2010 H04-TAQ/AM/es Ares(2010) NOTE TO DG ENTR Subject: Proposal for E75 reference fuel specifications for Type 6 test (emissions at low temperatures) Authors: Alessandro Marotta, Marta Rocha Contributors: Motor Vehicles Emission Group (MVEG) members Approved: Giorgio Martini

2 Proposal for E75 reference fuel specifications for Type 6 test (emissions at low temperatures) Introduction One of the pending issues of the Euro 5/6 implementation phase (see Commission Regulation (EC) No. 692/2008) is to define the specifications of the Ethanol/Gasoline (E75) reference fuel for the Type 6 test (emissions at low temperatures) for Flexi Fuel Vehicles (FFV). As stated in the above mentioned Regulation, such type approval test fuel will become mandatory from 1 September 2011, thus it is necessary to complete the technical definition of the E75 reference fuel specifications, to allow the car manufacturer to get ready in due time for this type approval test. Background information The process to derive a set of specifications for E75 reference fuel has been based on the following available information/contributions: 1. Currently available E85/E75 standard fuel specifications 2. Currently available E85/E75 market fuel quality data 3. E85 reference fuel specifications (Commission Regulation (EC) No. 692/2008) 4. Available scientific literature on emissions and drivability of FFVs fuelled with E85/E75 5. Consultation with MVEG members and finalization of the proposal 1. Currently available E85/E75 standard fuel specifications Standard fuel specifications for E85/E75 fuel are present in France, Germany, Sweden and USA. In addition there is a project CEN/TC19 standard (pren15293) aiming at defining requirements and test methods for E85/E75 fuel, which is close to its ballot stage (final step before official approval). All these standards consist of two tables, one containing the non-climate-related parameters, the other with the climate-related (seasonal) parameters. An overview of both parts of the available standards is given in the following pages.

3 Summary of E85/E75 non-climate-related requirements and test methods Parameter Research octane number, RON Motor octane number, MON Unit CEN Sweden Germany USA France Test method Min Max Min Max Min Max Min Max Min Max EN ISO EN ISO 5163 Density at 15 C kg/m EN ISO Vapour pressure kpa Sulphur content mg/kg EN 15485; EN EN ISO EN ISO EN ISO EN ISO Oxidation stability min EN ISO 7536 Existent gum content (solvent washed) mg/100 ml EN ISO 6246 ASTM D 381 Appearance This shall be determined at ambient temperature or 15 C whichever is higher clear clear and bright, free of any visible contaminate materials free of water and solid phases clear and bright clear and limpid, free of any visible contaminate EN visual inspection Ethanol and higher alcohols Higher alcohols (C3-C8) Higher alcohols (C3-C5) % (V/V) % (V/V) Methanol Petrol % (V/V) Phosphorus mg/l Water content Inorganic chloride content % (m/m) % (V/V) mg/l mg/kg phe Copper strip corrosion (3h at 50 C) Acidity (as acetic acid CH 3 COOH) Carbon/hydrogen ration Carbon/oxygen ration 6.5 to EN 228 EN pren ASTM D 3231 EN 15489; pren 15692; SS-ISO 760; EN ISO 12937; ASTM E 1064; EN 15489; pren ASTM E 203 or E 1064 EN 15492; EN 15492; SS-ISO 6227; ISO 6227 ASTM D 512 or D 2988 EN ASTM D 6423 ASTM D 6423 EN Rating Class 1 Class 1 Class 1 Class 1 EN ISO 2160 % (m/m) mg/l EN 1601 EN EN E DIN ASTM D 4815 EN ASTM D 1613 ASTM D1613 EN Electrical conductivity µs/cm Ethers (5 or more C atoms) Copper content Sulfate content % (V/V) mg/kg mg/l mg/kg mg/l pren DIN EN 1601 EN EN E DIN ASTM D EN pren ASTM D1688 EN 15492

4 Climate-related requirements and test methods - SWEDEN Climate-related requirements and test methods - GERMANY Climate-related requirements and test methods - FRANCE

5 Climate-related requirements and test methods - USA Climate-related requirements and test methods pren Currently available E85/E75 market fuel quality data The only market fuel quality data for winter have been provided by Sweden and are shown in the following table. (the Final Boiling Points of these samples are not correct due to measurement method problems)

6 From this very limited set of data two simple observations can be made: the Vapor Pressure ranges between 50 kpa (specification limit) and 60 kpa, with an average value of 53.8; the average ethanol content is 79.2% vol (the specification limit is 70% vol. min.) While the Vapor Pressure values of the Swedish winter E85 seem in line with most national and international standards, the average ethanol content is well above the prescribed minimum levels. This is probably due to a tax incentive mechanism related to a CO2-driven policy and is favored by the fact that in Sweden most FFVs are equipped with an electric engine-block heater which helps prevent cold start drivability and emissions problem. However the use of the electric engine-block heaters could not be widespread in the other EU countries where FFVs are sold or might be sold. 3. E85 reference fuel specifications (Commission Regulation (EC) No. 692/2008)

7 4. Available scientific literature on emissions and drivability of FFVs fuelled with E85/E75 There is quite extensive scientific literature on ethanol/gasoline blends and their impact on vehicle emissions and performances (including drivability at low ambient temperatures). However most data are related to ethanol/gasoline blends with an ethanol content between 5% and 10% vol. When we start considering ethanol/gasoline blends where ethanol varies from 50% to 85+% vol. and we restrict our attention to low temperatures (below 0 C) emission measurements from Flexi Fuel Vehicles (FFVs), then the available data are less abundant, but still sufficient to derive some commonly agreed conclusions: with decreasing ambient temperatures, exhaust emissions (-7 C) of most regulated and unregulated pollutants increase substantially; at ambient temperatures lower than -7 C some emissions are expected to increase even more substantially; as far as CO and HC are concerned, increased ethanol content in the ethanol/gasoline blends is not directly related to an increase of emissions at low ambient temperatures. Tests have shown that, comparing E5 with E85/E75, emissions of CO and/or HC can be either higher or lower, depending on the FFV and presumably on the engine tuning with respect to the ethanol content of the fuel; at low ambient temperatures, a decrease in the vapor pressure (VP) of the fuel is associated with an increase of cold start CO/HC emissions; increased ethanol content in the ethanol/gasoline blends (above 50%) is associated with a decrease in the vapor pressure (VP) of the fuel; an insufficient level of VP at low ambient temperatures can give rise to a drivability (startability) problem of the vehicle.

8 5. Contributions from stakeholders During the first phase of the activity to define E75 reference fuel specifications (i.e. gathering of all available information on this subject September/November 2009), in addition to the contributions of Member States that provided most of the data shown so far, ACEA submitted a written document and summarized its proposal regarding E75 reference fuel specifications in the attached note (ANNEX I). Following the presentation of the first draft proposal of E75 reference fuel specifications at the TCMV meeting in Brussels on 16 December 2009, the Finnish and the Swedish delegations have sent comments that are also reported here (ANNEX II and ANNEX III, respectively). All these contributions, which have substantially helped shaping this technical document, are acknowledged. Methodology and proposal The definition of the fuel quality requirements for the E75 reference fuel has been accomplished according to the following steps: Decision concerning non-climate-related parameters has been quite straightforward. Starting from the available fuel quality standards and from E85 reference fuel requirements, we have derived a list of proposed limits and test methods. The criterion has been to compare the values derived from the available standards with the specifications of E85 reference fuel and to choose, when reasonable and possible, the most severe values among them. The choice concerning climate-related parameters (in particular ethanol content and vapor pressure) has been less simple. As it can be seen from the existing climate-related specifications of CEN/TC19, France, Germany, Sweden and USA, there are several different combinations of ethanol content vs. minimum VP for the winter season. As an example, for a fixed min VP value of 60 kpa the corresponding ethanol content can span from 50% to 80%. Conversely, considering an ethanol content of 70%, the min VP can vary from 50 kpa to 70+ kpa. In the following diagram an overview of this variability is shown (the yellow area represents the cold season boundary limits obtained from all available data). Technically speaking the E75 reference fuel specifications of VP and ethanol content could be chosen with quite a high degree of freedom. A lower min VP limit associated with a higher max ethanol limit (ex. min VP=50 kpa; max Eth.=85%) would be a CO2-driven choice. On the opposite side, a higher min VP limit coupled to a lower max ethanol content (ex. min VP=60 kpa; max Eth.=60%) would be an emission-driven choice. Traditionally the definition of the requirements and test methods for reference fuels has been based on the averaging of the market fuel quality data. In our opinion such an approach would not be completely appropriate in this case, for two reasons. First, E85/E75 is a relatively new fuel in Europe, thus there is not a robust historical database of market

9 fuel quality data (especially for the winter grade). Secondly, considering the limited market fuel quality data available (i.e. the Swedish data), it seems that the average ethanol content in that case is the result of a CO2-driven policy, which pushes the ethanol content to the max technically feasible in winter. For this reason, in our opinion, a wider range of ethanol content in the E75 reference fuel specification should be allowed, in order to possibly take into account the two different approaches that could be adopted to set the ethanol limits in the winter season. However, by doing so, we make sure that the proposed fuel specifications lie within the yellow area of the already mentioned diagram (which, as previously stated, represents the cold season boundary limits of E75 fuel specifications). Overview of current climate-related limits for minimum ethanol content and minimum VP Note: the ethanol and VP market quality data are actual values, while the other points only show min VP and min Ethanol %. SW Sweden S Summer 1,2,3 ASTM classes GE Germany W Winter a,b,c,d CEN classes 16/3-30/4 FR France OS Off - Season 1/10-15/12 Once the E75 fuels specifications were defined, the relevant parameters have been derived for the execution of Type 6 emission tests (Appendix 8 to Annex 4 of UNECE Regulation 83; Article 2(3) and sections 3.4, 3.8 and 3.10 of Annex III, and Annex VIII of Regulation 692/2008/EC) and for the determination of CO2 emissions and fuel consumption (Section of Annex 6 of UNECE Regulation 101; section 2.3 and 3.3 of Annex XII to Regulation 692/2008/EC).

10 Proposed requirements and test methods for E75 reference fuel Parameter Unit Minimum Limits (1) Maximum Test method (2) Research octane number, RON EN ISO 5164 Motor octane number, MON EN ISO 5163 Density at 15 C kg/m 3 report EN ISO Vapour pressure kpa Sulphur content (3) (4) mg/kg EN ISO (DVPE) EN ISO EN ISO Oxidation stability minutes EN ISO 7536 Existent gum content (solvent washed) Appearance This shall be determined at ambient temperature or 15 C whichever is higher mg/100ml -- 4 EN ISO 6246 Clear and bright, visibly free of suspended or precipitated contaminants Ethanol and higher alcohols (7) % (V/V) Higher alcohols (C3 - C8) % (V/V) -- 2 Methanol -- 0,5 Visual inspection EN 1601 EN EN Petrol (5) % (V/V) Balance EN 228 (6) ASTM D 3231 Phosphorus mg/l 0.30 EN Water content % (V/V) -- 0,3 ASTM E 1064 EN Inorganic chloride content mg/l ISO EN phe 6,50 9 ASTM D 6423 EN Copper strip corrosion (3h at 50 C) Rating Class 1 EN ISO 2160 Acidity (as acetic acid % (m/m) 0,005 ASTM D1613 CH 3 COOH) mg/l 40 EN Carbon/hydrogen ration report Carbon/oxygen ration report (1) The values quoted in the specifications are true values. In establishment of their limit values the terms of ISO 4259 Petroleum products Determination and application of precision data in relation to methods of test have been applied and in fixing a minimum value, a minimum difference of 2R above zero has been taken into account; in fixing a maximum and minimum value, the minimum difference is 4R (R = reproducibility). Notwithstanding this measure, which is necessary for technical reasons, the manufacturer of fuels shall nevertheless aim at a zero value where the stipulated maximum value is 2R and at the mean value in the case of quotations of maximum and minimum limits. Should it be necessary to clarify whether a fuel meets the requirements of the specifications, the terms of ISO 4259 shall be applied. (2) In cases of dispute, the procedures for resolving the dispute and interpretation of the results based on test method precision, d EN ISO 4259 shall be used. (3) In cases of national dispute concerning sulphur content, either EN ISO or EN ISO shall be called up similar to the reference in the national annex of EN 228. (4) The actual sulphur content of the fuel used for the Type 6 test shall be reported. (5) The unleaded petrol content can be determined as 100 minus the sum of the percentage content of water and alcohols (6) There shall be no intentional addition of compounds containing phosphorus, iron, manganese, or lead to this reference fuel. (7) Ethanol to meet specification of EN is the only oxygenate that shall be intentionally added to this reference fuel.

11 Parameters to be used for the Type 6 emission tests (Appendix 8 to Annex 4 of UNECE Regulation 83; Article 2(3) and sections 3.4, 3.8 and 3.10 of Annex III, and Annex VIII of Regulation 692/2008/EC) and for the determination of CO2 emissions and fuel consumption (Section of Annex 6 of UNECE Regulation 101; section 2.3 and 3.3 of Annex XII to Regulation 692/2008/EC) E75 Reference Fuel Hydrocarbons ratio C 1 H 2.61 O Density (g/l) (also Q THC ) X value for Dilution Factor 12.7 Fuel Consumption Formula FC = (0.1655/D)*[(0.604*HC)+(0.429*CO)+(0.273*CO2)]

12 ANNEX I ACEA position on E75 cold start reference fuel (a) Introduction: Following the request from Mr Jean on 18 th August 2009, ACEA has reviewed the situation regarding the current CEN work to develop a market fuel specification for E85 and the basic requirements that must be addressed in specifying an appropriate reference fuel for flex-fuel vehicles when they are tested on the cold start (Type VI) test which will be applicable from 1 st September 2011 to new types of spark-ignition engine flex-fuel vehicles. ACEA also requested the CEC reference fuels group to look into the measurement methods for the various fuel specifications. We understand that this is on-going in CEC RFG and will be a necessary part of the final specification table. (b) Status in CEN E85-TF: The enquiry stage for the draft CEN E85 standard (attached) is complete and they are now reviewing the more than 130 comments received on the draft. The convenor of CEN TF-E85 appears to be confident that the CEN E85 standard (based on a consensus between the auto and oil industries) might be adopted next year. The effect on exhaust emissions etc when vehicles are operated at normal and low ambient temperatures have been addressed in the setting of appropriate cold temperature specifications, or classes. A report had been forwarded to CEN TC19 explaining the background to the activity (attached). In particular, this report explains why existing market fuel specifications for ethanol blended gasoline is not a meaningful basis on which to set the various cold temperature specifications in the draft CEN standard. This is the view of ACEA, that historic market data for gasoline-ethanol blends (in the range 70% - 80%) are not a correct basis for deciding on a specification for a cold start E75 test reference fuel. (c) Proposal for E75 cold start reference fuel specification: The following comments deal with the main parameters for a cold start reference fuel: Ethanol content: The basic principle for a test reference fuel is that it should replicate a nominal market fuel specification. It has been clear in CEN TF-E85 that an ethanol/petrol ratio needed to meet a minimum RVP of 60kPa needs to have an ethanol content as low as ~ 60 %v/v and this is the reason why the current proposal for a CEN E85 specification is so different compared to existing national E85 specifications across the EU. A future test reference fuel for the Type VI test on E85 must be based on a nominal 70% v/v ethanol content, and a band of 68 to 72% v/v ethanol content is therefore appropriate. We believe that in future winter ethanol market fuels will commonly have lower ethanol content and the Type VI test reference fuel should reflect this. ACEA s proposal is for an ethanol range of 68 %v/v (min) 72 %v/v (max). Vapour pressure: ACEA s proposal is for a vapour pressure range of 65kPa (min) 75kPa (max). Water content: Since ethanol is hygroscopic and can collect water in the distribution and storage system, it is advisable to have a higher maximum water limit for higher ethanol blend gasoline. ACEA s proposal is for a water content of 0.3 % m/m (max). Phosphorus:

13 ACEA s proposal is a for a phosphorus content of 0.15mg/l (max). Chloride, electrical conductivity and sulphate: ACEA s proposal is for a chloride content of 0.15mg/l (max), an electrical conductivity of 1.5µS/cm (max) and a sulphate content of 2.0mg/kg (max). RON & MON: Appropriate values for RON and MON should be proposed to avoid the use of synthetic fuels and to align with the draft CEN E85 specifications. ACEA Has some concerns about the draft CEN E85 standard prescribing indicative limits and what that would actually mean for market fuels. ACEA s proposal is for a RON of 104 (min) and a MON of = 88 (min), both with no maximum specifications. Density: The draft CEN E85 specification notes density as report but an actual density range in the reference fuel specifications would provide more security for fuel injection calibration etc. The actual density range could therefore be added to correspond to the proposed ethanol range of 68 %v/v (min) 72 %v/v (max). [to check]. Existent gum: A lower limit should be specified to foresee future engine needs while recognising the practical limitations of the test method. ACEA s proposal is for an existent gum content of 4mg/100ml (max). Test methods: ACEA recommends that CEC RFG advise on the appropriate test methods. (d) Summary: ACEA s draft proposal for E75 cold start reference fuel is shown in the attached excel file in the worksheet ACEA proposal for E75 spec.

14 The other worksheets in that file show: A chart of ethanol content against RVP, plotted for various BOB RVPE; A chart of ethanol content against RVP, plotted for various BOB RVPE and showing the pen15293 volatility classes; A summary of the pren15293 classes. (d) Other issues: E85: Taking account of the soon to be agreed CEN E85 market fuel specification, ACEA also recommends that the Commission review the existing E85 test reference fuel specification in Annex IX of Regulation 692/2008. Ethanol denaturants: Ethanol is denatured alcohol that has additives to make it toxic, unpalatable, or otherwise undrinkable. In some cases it is also dyed. Article 27(1)(a) of Council Directive 92/83/EEC provides the legal base for exempting from excise duty alcohol which has been completely denatured in accordance with the requirements of any Member State and ratified in Commission Regulation (EC) No 3199/93. Article 27(1)(b) provides the legal base for exempting from duty alcohol which has been denatured in accordance with the requirements of any Member State and used for the manufacture of any product not for human consumption. There are currently no harmonised European standard practices for denaturing, instead the standards are devised by the Member States which has led to a multiple of different denaturing methods being used. Once denatured to a Member State's standards, subject to certain legal conditions, the alcohol should be accepted by other Member States as exempt from duty. It is noted that DG TAXUD has recently launched a project to look into the feasibility of establishing 'eurodenaturants' for the purposes of exemption from alcohol duty.

15 Petrol is accepted in some countries like Germany as a denaturant, while other countries only accept certain components. The auto-industry is concerned that some of these denaturing components have a higher boiling point than ethanol and will present cold startability problems. We are also concerned that we different test fuels in different Member States. Therefore, ACEA recommends that in the case of ethanol blended test reference fuels, petrol should be accepted as a denaturing component across the EU in order to avoid different test reference fuels in different Member States, due to the situation noted above and, especially in the case of the cold start test, to avoid unwarranted effects on the measured emissions. ACEA recommends the Commission includes this proposal in its deliberations on test reference fuels. Finally, ACEA will be pleased to work with JRC to help define the appropriate E75 test reference fuel specification. Dr Paul Greening Director Emissions & Fuels, ACEA 23 rd October 2009

16 ANNEX II Comments from FI to the proposed E75/E85 reference fuel specifications; proposal laid down on the TCMV meeting 16 th December, 2009 Min/Max levels of RON and MON: FI sees that the levels 85 and 95 should be followed as in the standard. Measuring RON above 100 causes problems. Max level of higher alcohols C3-C8: should be limited to 2 %. The specifications should follow specifications of fuels on market. Vapor pressure and content of ethanol and higher alcohols: the proposed limits differ from standard, but together correspond better with winter conditions and actual cold start emissions. FI can support the limits.

17 ANNEX III

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