Alternative fuels Investigation on emission effects of alternative fuels Literature overview For the Norwegian Environment Agency (Miljødirektoratet) M-291|2015 Date: ...................................................... 2012-12-04 Presented by: ........................................... AVL MTC Address: .................. Armaturvägen 1, P.O Box 223 ................................................. SE-136 23 Haninge ................................................................... Sweden Document - Type Prepared by Draft report Charlotte Sandström-Dahl - 2 - Date – Rev Document - Ref Page 2015-01-29 Emission effects of biofuels M- 2 (91) - 2 - - 2 -) 291 2015 endelig rapport.docx 1 Summary AVL was asked by the Norwegian Climate and Pollution Agency (KLIF, now Norwegian Environment Agency/Miljødirektoratet) to give a scientific overview of the emissions from alternative fuels compared to conventional fuels. The latest scientific findings have been reviewed and interviews with AVL in-house experts have been carried out in order to create an overview of the current market concerning conventional and alternative fuels. There are reasons to believe that the field of alternative fuels, and especially biofuels, will develop fast in the near future. In this literature study, scientific reports involving biofuels have been summarized. The different methods for sampling and analysing the unregulated compounds make comparison difficult. The main conclusion drawn from this study is that the exhaust emissions from different biofuels and blends with biofuels have to be studied more thoroughly, including both regulated and unregulated compounds. The exhaust emissions generated during testing should be further evaluated regarding health effects. The fuel quality provided on the national market is an important factor for improving local air quality and for reducing health effects from exhaust emissions. The future emission legislation will lead to reduced emissions from new vehicles through more extensive use of exhaust aftertreatment systems (such as SCR and diesel particulate filters) and other technological improvements. This does however not affect the emissions from existing vehicles. The major benefit when improving the fuel quality is that this also affects emissions from all existent vehicles and non-road mobile machinery. There are some conclusions concerning emissions from alternative fuels that can be drawn. Table 1 below gives an overview of alternative and conventional fuels and the emission components from each fuel. The fuels currently available on the Norwegian market are outlined with yellow. The effect on the exhaust when adding biodiesel to fossil diesel is dependent on the concentration of the blend, as well as operating conditions (urban driving vs mtorway). For both light duty and heavy duty vehicles the regulated emissions of CO, HC and PM are generally reduced when biodiesel is blended into fossil diesel. Emissions of NOx are generally increased with biodiesel blends. In addition to contributing to the formation of ground-level ozone, and fine particle pollution, NO2 is linked with a number of adverse effects on the respiratory system. 2 | P age Document - Type Prepared by Draft report Charlotte Sandström-Dahl - 3 - Date – Rev Document - Ref Page 2015-01-29 Emission effects of biofuels M- 3 (91) - 3 - - 3 -) 291 2015 endelig rapport.docx Table 1: Overview of fuels Renewable fuel Fuel, commercially Raw material(s) Highlighted emission Is conversion of the available components engine/vehicle required in order to use this fuel? Fossil Petrol Crude oil Crude oil Aromats, PAH, Fossil Diesel Mutagenic, NOx, particles BioMethane (upgraded CNG/LNG (biogas Biomass CH4, NOx (technology YES. Major adjustments Biogas) origin) dependent) E.g. vegetable oils, wood Nox YES. Minor adjustments B100 and animal fat BioDiesel (FAME) E.g. vegetable oils, wood NOx Compatible if complying with Low blends in fossil and animal fat B20 mutagenic blending requirements in diesel (inconclusive evidence!) EN590 Renewable petrol E.g. vegetable oils, wood -- Compatible if compliant with Hydrogenated and diesel (high and animal fat EN228/EN590 Vegetable Oil (HVO) blend) Low to medium E.g. vegetable oils, wood -- Compatible if compliant with blends in fossil fuel and animal fat EN228/EN590 E.g. crops/biomass with Ultrafine particles, YES. Minor adjustments ED95 sugar and/or starch aldehydes (mainly content acetaldehyde) E.g. crops/biomass with Aldehydes (mainly YES. Minor adjustments Ethanol E85/E100 sugar and/or starch acetaldehyde) content E.g. crops/biomass with -- Compatible if complying with Low blends in fossil sugar and/or starch blending requirements in petrol content EN228 DME, DiMethylEther Natural gas, coal or Inconclusive YES. Major adjustments DME biomass Synthetic diesel Renewable petrol Natural gas (GTL), coal Inconclusive Compatible if compliant with (Fischer-Tropsch diesel) and diesel (high (CTL), any kind of EN228/EN590 blend) biomass (BTL) Natural gas (GTL), coal -- Compatible if complying with Low to medium (CTL), any kind of blending requirements in blend in fossil fuel biomass (BTL) EN228/EN590 Methanol Methane (natural gas, Toxic when handling! Insufficient experience M85/M100 biogas) steam reformed Aldehydes (mainly coal, woody biomass formaldehyde) Biomass or fossil fuels Inconclusive Insufficient experience High blend Biomass or fossil fuels Aldehydes Compatible if compliant with Butanol Low blend in fossil (formaldehyde and blending requirements in petrol acetaldehyde) EN228 Carbonyls When adding bioethanol to fossil petrol, the effects on CO and NOx are contradictive, probably due to engine calibration. The THC and NMHC increases for E85 blend. The emissions consist mainly of unburnt ethanol. Significant increases of aldehydes (mainly acetaldehyde) were observed for E85, whereas lower blends showed decreases of 3 | P age Document - Type Prepared by Draft report Charlotte Sandström-Dahl - 4 - Date – Rev Document - Ref Page 2015-01-29 Emission effects of biofuels M- 4 (91) - 4 - - 4 -) 291 2015 endelig rapport.docx formaldehyde. Ethanol is the main precursor of acetaldehyde in vehicle emissions. Acetaldehyde is considered a probable carcinogen, and formaldehyde is carcinogenic. In Table 2 the NOx and PM emissions for the different fuels are summarized. The evaluations are based on concordant test results (when applicable), and are presented in comparison with the respective conventional fossil fuel. Please note that it is important to combine the emission result with the specific testing conditions (for further details, see chapter for respective fuel). Table 2: Summary of NOx and PM emissions, as compared to conventional fossil fuel Fuel NOx emissions PM emissions Fossil Petrol Low Low Fossil Diesel High High BioMethane - (technology dependent) Low BioDiesel (FAME) High Low Hydrogenated - Low Vegetable Oil (HVO) ED95 Low Low (overall; high levels of ultrafine particles) E85 - - DME Low Low Synthetic diesel - Low (Fischer-Tropsch diesel) Methanol ? ? Butanol ? ? 4 | P age Document - Type Prepared by Draft report Charlotte Sandström-Dahl - 5 - Date – Rev Document - Ref Page 2015-01-29 Emission effects of biofuels M- 5 (91) - 5 - - 5 -) 291 2015 endelig rapport.docx Table of content Alternative fuels............................................................................................................................. 1 Investigation on emission effects of alternative fuels ......................................................................... 1 Literature overview ........................................................................................................................ 1 1 Summary .............................................................................................................................. 2 2 Background .......................................................................................................................... 8 3 Scope ................................................................................................................................... 8 4 Deliverables .......................................................................................................................... 8 5 Result ................................................................................................................................... 8 5.1 Overview of different fuels ............................................................................................... 9 5.2 Overview of fuels suitable for different vehicles ................................................................ 10 5.3 Emission requirements and aftertreatment systems ......................................................... 11 5.4 Health impacts.............................................................................................................. 14 5.4.1 Health effects ...................................................................................................... 15 5.5 Health effects and exhaust emissions – biofuels vs conventional fuels ............................... 19 5.5.1 Fossil petrol ........................................................................................................ 19 5.5.2 Fossil diesel ........................................................................................................ 25 5.5.3 BioMethane (Biogas) ........................................................................................... 30 5.5.4 Biodiesel (FAME) ................................................................................................ 37 5.5.5 Hydrogenated Vegetable Oil (HVO) ...................................................................... 47 5.5.6 Ethanol ............................................................................................................... 52 5.5.7 ED95 .................................................................................................................. 57 5.5.8 Dimethyl ether (DME) .......................................................................................... 61 5.5.9 Synthetic diesel (Fischer-Tropsch diesel) ............................................................... 64 5.5.10 Methanol ............................................................................................................ 68 5.5.11 Butanol ............................................................................................................... 70 5.6 Prices on fuels .............................................................................................................. 72 5.7 Future expectations ...................................................................................................... 72 5.7.1 Bi-fuels ............................................................................................................... 72 6 Conclusion .......................................................................................................................... 73 7 Bibliography ........................................................................................................................ 74 8 Appendix ............................................................................................................................ 77 5 | P age Document - Type Prepared by Draft report Charlotte Sandström-Dahl - 6 - Date – Rev Document - Ref Page 2015-01-29 Emission effects of biofuels M- 6 (91) - 6 - - 6 -) 291 2015 endelig rapport.docx Abbreviations ADEME ”Agence De l'Environnement et de la Maîtrise de l'Energie”, French Environment and Energy Management Agency B20 20% Biodiesel B100 100% Biodiesel ("neat" Biodiesel) BRA Braunschweig City Driving Cycle BTEX Short for Benzene, Toluene, Ethyl benzene and Xylenes BTL Biomass To Liquid CARB California Air Resource Board CBG Compressed Bio Gas CI Compression Ignition CNG Compressed Natural Gas CONCAWE CONservation of Clean Air and Water in Europe, the oil companies' European association for environment, health and safety in refining and distribution CTL Coal To Liquid DPF Diesel Particle Filter DTT Dithiothreitol EEV Enhanced Environmentally friendly Vehicle EGR Exhaust Gas Recirculation EPA See US EPA EUCAR European Council for Automotive R&D FAME Fatty Acid Methyl Ester F-T Fischer- Tropsch, collection of chemical reactions that converts a mixture of carbon monoxide and hydrogen into liquid hydrocarbons FTP75 Federal Test Procedure 75, emission certification of light duty vehicles in the U.S. GHG Greenhouse Gas GTL Gas To Liquid HDV Heavy Duty Vehicle IARC International Agency for Research on Cancer IEA International Energy Agency ILUC In-Direct Land Use Change JE05 Japanese 2005 emission standards, transient test based on Tokyo driving conditions. LBG Liquified Bio Gas LNG Liquified Natural Gas MSS Micro Soot Sensor MTBE Methyl Tertiary Butyl Ether NEDC New European Driving Cycle NYBUS New York Bus cycle, chassis dynamometer test for heavy-duty vehicles, 6 | P age Document - Type Prepared by Draft report Charlotte Sandström-Dahl - 7 - Date – Rev Document - Ref Page 2015-01-29 Emission effects of biofuels M- 7 (91) - 7 - - 7 -) 291 2015 endelig rapport.docx particularly for urban buses OEM Original Equipment Manufacturer PAH Polycyclic Aromatic Hydrocarbons PME Palm oil Methyl Ester RED Renewable Energy Directive RME Rapeseed Methyl Ester (oil) ROS Reactive Oxygen Species ROW Rest Of the World SCR Selective Catalytic Reduction SI Spark Ignition SME Soybean oil Methyl Ester TEF Toxic Equivalence Factor TEOM Tapered Element Oscillating Microbalance THC Total Hydro-Carbon emission UDDS US EPA Urban Dynamometer Driving Schedule UFOME Used Frying Oil Methyl Esters US EPA United States Environmental Protection Agency VOC Volatile Organic Compounds VTT Valtion Teknillinen Tutkimuskesk, Technical Research Center, Finland WHO-IPCS World Health Organization - International Program on Chemical Safety WHVC Worldwide Harmonized Vehicle Cycle 7 | P age Document - Type Prepared by Draft report Charlotte Sandström-Dahl - 8 - Date – Rev Document - Ref Page 2015-01-29 Emission effects of biofuels M- 8 (91) - 8 - - 8 -) 291 2015 endelig rapport.docx 2 Background In November 2012 AVL was asked by the Norwegian Climate and Pollution Agency (KLIF, now Norwegian Environment Agency) to give an overview of scientific findings regarding emissions from alternative fuels in comparison with conventional fuels. The focus is on the Norwegian market, but the report does also include information regarding Europe and ROW (Rest Of the World). 3 Scope The objective of this report is to provide the Norwegian authorities with information regarding biofuels. The fuels described in this report are either used today, or under development. A scientific overview of emission components has been performed. Facts concerning practical issues have been investigated, i.e. blends, conversion possibilities and raw material needed to produce the fuel. 4 Deliverables This report gives an overview of the latest scientific findings regarding emissions from biofuels. In addition to a literature study, interviews with in-house experts have been carried out in order to create an overview of the current market concerning conventional and alternative fuels. The report has a focus on renewable fuels. Fossil petrol and fossil diesel are mentioned as references. The fuels available on the Norwegian market and the efforts put on renewable fuels do not differ substantially from the European market. Therefore, the report does not specifically state the situation on the Norwegian market. 5 Result The information and data stated in the report have been collected from scientific articles and corporate publications, as well as data provided by in-house experts. 8 | P age Document - Type Prepared by Draft report Charlotte Sandström-Dahl - 9 - Date – Rev Document - Ref Page 2015-01-29 Emission effects of biofuels M- 9 (91) - 9 - - 9 -) 291 2015 endelig rapport.docx 5.1 Overview of different fuels Different fuels currently existing on the market as well as fuels that are under development are presented in Table 3. Fuels currently available on the Norwegian marked are outlined with yellow colour. Table 3: Overview of fuels Renewable fuel Fuel, commercially Raw material(s) Highlighted emission Is conversion of the available components engine/vehicle required in order to use this fuel? Fossil Petrol Crude oil Crude oil Aromats, PAH, Mutagenic, Fossil Diesel NOx, particles BioMethane CNG/LNG (biogas Biomass CH4, NOx (technology YES. Major adjustments (upgraded Biogas) origin) dependent) E.g. vegetable oils, Nox YES. Minor adjustments B100 wood and animal fat BioDiesel (FAME) E.g. vegetable oils, NOx Compatible if complying with Low blends in fossil wood and animal fat B20 mutagenic blending requirements in diesel (inconclusive evidence!) EN590 Renewable petrol E.g. vegetable oils, -- Compatible if compliant with Hydrogenated and diesel (high wood and animal fat EN228/EN590 Vegetable Oil (HVO) blend) Low to medium E.g. vegetable oils, -- Compatible if compliant with blends in fossil fuel wood and animal fat EN228/EN590 E.g. crops/biomass with Ultrafine particles, YES. Minor adjustments ED95 sugar and/or starch aldehydes (mainly content acetaldehyde) E.g. crops/biomass with Aldehydes (mainly YES. Minor adjustments Ethanol E85/E100 sugar and/or starch acetaldehyde) content E.g. crops/biomass with -- Compatible if complying with Low blends in fossil sugar and/or starch blending requirements in petrol content EN228 DME, DiMethylEther Natural gas, coal or Inconclusive YES. Major adjustments DME biomass Synthetic diesel Renewable petrol Natural gas (GTL), coal Inconclusive Compatible if compliant with (Fischer-Tropsch and diesel (high (CTL), any kind of EN228/EN590 diesel) blend) biomass (BTL) Natural gas (GTL), coal -- Compatible if complying with Low to medium (CTL), any kind of blending requirements in blend in fossil fuel biomass (BTL) EN228/EN590 Methanol Methane (natural gas, Toxic when handling! Insufficient experience M85/M100 biogas) steam reformed Aldehydes (mainly coal, woody biomass formaldehyde) Biomass or fossil fuels Inconclusive Insufficient experience High blend Butanol Biomass or fossil fuels Aldehydes (formaldehyde Compatible if compliant with Low blend in fossil and acetaldehyde) blending requirements in petrol Carbonyls EN228 9 | P age Document - Type Prepared by Draft report Charlotte Sandström-Dahl - 10 - Date – Rev Document - Ref Page 2015-01-29 Emission effects of biofuels M- 10 (91) - 10 - - 10 -) 291 2015 endelig rapport.docx The emission components listed in Table 3 are based on the studies summarized in this literature study. The listed effects are the known negative effects to date. The biofuels have been compared to the conventional fuel (i.e. biodiesel has been compared to fossil diesel). The overview of fuels presented in Table 3 does not include any details on availability of fuels on different markets. Several fuels are under development with limited supply, but the situation changes rapidly as the development progresses and modifications and improvements are introduced and different feedstocks are tested. Any information on current production capacity is therefore omitted from this report. Data on current fuel prices is omitted due to the difficulties in obtaining correct information on fuel prices excluding taxes and environmental charges to give a correct picture of current fuel prices. It is important to notice that under the current emission legislation for engines/vehicles, requirements must be met and can already today be a challenge. The introduction of Euro VI emission levels will further increase the complexity. 5.2 Overview of fuels suitable for different vehicles Some fuels are more suitable for urban traffic than for long distance haulage, due to higher fuel consumption and limited fuel storage on the vehicle (compared to fossil diesel or petrol). When the mileage range will be a limitation, the availability of filling stations becomes a decisive factor. Table 4 show fuels suitable for different vehicle sizes, driving patterns and combustion types. 10 | P age