BOLK: Impact of biofuels on engine technology and emissions 17 April 2008 VROM, Den Haag Ruud Verbeek / Richard Smokers
Contents Objectives / introduction Engine development & compatibility with renewable fuels Emissions with renewable and other alternative fuels Conclusions & Recommendations 2
Objectives Impact biofuels and other alternative fuels on emissions of current technology vehicles Impact biofuels on emissions of future vehicles (up to 2020) 3
Fuels considered low % blends in petrol E5 - E10 ethanol ETBE Butanol / biopetrol SI engines high % blends neat fuels E85 E100 gaseous fuels LPG CNG CBG (biogas) diesel low % blends B5-B10 (FAME) VPO (PPO) XTL: BTL, GTL HVO diesel engines high % blends neat fuels B20-B100 E95 + ignition improver 100% XTL 100% HVO methanol / DME 4
Fuels development Governments steer the quantity of bio components in fuels for road transportation in the total amount of fuels sold for road transport in petrol min. in diesel min. 2007 2% 2% 2% 2008 3,25% 2,5% 2,5% 2009 4,5% 3% 3% 2010 5,75% 3,5% 3,5% 2020 10%? 5
Contents Objectives / introduction Engine development & compatibility with renewable fuels Emissions with renewable and other alternative fuels Conclusions & Recommendations 6
Emissions legislation passenger cars Euro normen 7
Engine development towards 2020 Engine Emphasis Spark ignition CO2 emission reduction Compression ignition NOx & PM emission reduction Developments Downsizing (turbocharging, DI, VVA, etc.) Further optimisation 3-way catalyst Advanced emission control systems: -Diesel particulate filter -Improved EGR systems -NOx reduction catalysts (almost) equal emission performance for otto and diesel with Euro VI / 6! 8
Engine compatibility with renewable fuels Aspect biofuel Consequence Biofuels not implemented in emission legislation (phasing in in future legislation) Energy density is often lower Biofuels can contain impurities Biofuels are more aggressive Different boiling range, viscosity & stability Emissions may vary and exceed limits Reduced driving range and/or increased tank size Possible catalyst deterioration and engine fouling Metal corrosion Deterioration Elastomers + coatings Engine oil deterioration 9
Contents Objectives / introduction Engine development & compatibility with renewable fuels Emissions with renewable and other alternative fuels Conclusions & Recommendations 10
Effects ethanol (petrol = 100%) CO HC E5 E10 E17 E20 E43 E70 E85 E5 E10 E17 E20 E43 E70 E85 250% 250% rel. CO emission 200% 150% 100% 50% 0% 0 10 20 30 40 50 60 70 80 90 100 Ethanol [vol%] rel. HC emission 200% 150% 100% 50% 0% 0 10 20 30 40 50 60 70 80 90 100 Ethanol [vol%] CO2 NOx E5 E10 E17 E20 E43 E70 E85 E5 E10 E17 E20 E43 E70 E85 rel. CO2 emission 110% 105% 100% 95% 90% 85% 0 10 20 30 40 50 60 70 80 90 100 Ethanol [vol%] rel. NOx emission 1200% 1000% 800% 600% 400% 200% 0% 0 10 20 30 40 50 60 70 80 90 100 Ethanol [vol%] 11
Effects biodiesel (diesel = 100%) NOx emissions HD NOx emissions LD 160% 160% 140% 140% relative NOx emissions 120% 100% 80% 60% 40% relative NOx emissions 120% 100% 80% 60% 40% 20% 20% 0% 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% 0% 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% % biodiesel % biodiesel PM emissions LD PM emissions HD 200% 200% 180% 180% relative PM emissions 160% 140% 120% 100% 80% 60% 40% 20% 0% 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% % biodiesel relative PM emissions 160% 140% 120% 100% 80% 60% 40% 20% 0% 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% % biodiesel 12
Effects VPO (PPO) Relative VPO emissions Euro 2 and 3 HD engines (diesel = 100%) CO THC NOx PM10 Relative VPO emissions Euro 2 LD vehicles (diesel = 100%) CO THC NOx PM10 160% 600% 140% 120% 100% 500% 400% 80% 60% 40% 20% 300% 200% 100% 0% 0 0% 0 13
Effects XTL (100% = diesel) Relative GTL LD emissions CO THC NOx PM10 Relative GTL HD emissions CO THC NOx PM10 120% 110% 100% 90% 80% 70% 60% 50% 40% 0 120% 110% 100% 90% 80% 70% 60% 50% 40% 0 GTL Fossil fuel (alkane, paraffine) Very good combustion properties (high cetane number) Excellent as blend Low density (0.77 kg/dm^3) Emission advantages of GTL proportional with blend % 14
Implementation biofuel (blends) in legislation Low blends petrol and diesel: E5 and B5 as standard test fuels for Euro 5: phase in 2009-2010 Spark ignition / FFV: Euro 5b: test with E85 (resp. E75) for FFV (same as petrol) phase in 2011-2012 Compression ignition B100: Test requirements still under discussion 15
Leveling of NOx with exhaust aftertreatment NOx emissions before and after catalyst of a turbocharged CI engine with variable EGR and a DPNR aftertreatment system [Kawano 2007] 16
Impact of biofuels on air quality and climate change (passenger cars Euro 4 to Euro 6) NOx and PM10 emissions Negative effect on air quality 100% E4 25% Bio Diesel PPO E4- DPF E5 Diesel LPG retrofit Petrol Biogas E85 CNG OEM 50% Green-House Gas emissies (WTW) Negative effect on climate change WTW CO2 from Proposal for a Directive of the European Parliament and of the Council on the promotion of the use of energy from renewable sources, Annex VII, page (2008/0016 (COD) 17
Contents Objectives / introduction Engine development & compatibility with renewable fuels Emissions with renewable and other alternative fuels Conclusions & Recommendations 18
Conclusions for spark ignition engines (1) Spark ignition / ethanol: E10 suitable for 90-95% of existing vehicles and 100% of future vehicles E5 in type approval legislation Up to E85 compatible with FFV Effect ethanol blends on emissions: Risks of NOx rise with > E10 for both standard and FFV vehicles Lack of real world emissions data NOx within limits for FFVs sold after 2012 19
Conclusions for spark ignition engines (2) ETBE: Bio-ETBE: good compatibility with petrol but limited renewable, high blends not implemented in legislation. Probably limited effect on emissions Biopetrol and butanol: production technology and economics still need to be demonstrated. Good compatibility with existing engine technology. LPG / CNG: Good emission performance with OEM vehicles Concerns about emissions for retrofit vehicles 20
Conclusions compression ignition engines (3) FAME (biodiesel): Biodiesel has substantial impact on engines Max 7% FAME (B7) recommended for passenger cars & LD Little experience with B20 B100. Trucks available with adaptation packages. Also as retrofit. Increased maintenance. Effects FAME on emissions: HD vehicles: B20-B100 on Euro III: 0-70% PM reduction, 0-30% NOx increase Possible large NOx increase with Euro IV and V! NOx probably all right for Euro VI and later (if closed loop NOx control) Passenger car and LD: B20-B100: PM and NOx variations up to 40% resp. 20% Phasing in of FAME (blend) in emission legislation necessary! 21
Conclusions compression ignition engines (4) XTL: HVO, BTL and GTL No adverse effects on maintenance in any blend %. Ideal blend fuel. With 100% XTL: Reduction emissions: NOx (-10%), PM (-20%), HC, CO for Euro III. 5-10% loss of power and driving range VPO: more compatibility issues than with FAME -> Not recommended Similar effects on emissions E95: bio-ethanol with ignition improver: suitable for niche markets, good emission performance Bio-methanol and Dimethyl-ether (DME) require consensus between industry and government. Long development time needed. 22
Recommendations for fuel mix Choose limited number of variants in bio-components: Main Stream Niche SI (petrol) E5 for old vehicles E5 or E10 for main stream E85 for FFV CBG for captive fleets Biopetrol if available CI (diesel) B5 or B7 for main stream B20 B100 for adapted vehicles HVO, BTL to increase bio share High purity desired for compatibility with emission control systems Low water content desired for easiness of distribution 23
Recommendations for R&D Interaction biofuels with Euro 5 & 6 emission control technology Emissions measurements necessary (possibly in international cooperation): E5-E10 in petrol Euro 5 & 6 E85 in FFV Euro 4 & 5 B7 in diesel passenger car B20-100 in diesel heavy duty Butanol / biopetrol Retrofit LPG (CNG) Evaluation emissions possible toxic components with biofuels & blends Review results with car and fuels industry 24
Thank you Questions? 25
Policy Recommendations International cooperation for: policy development development of emissions measurements (real world, in-use compliance) scientific check Implement desired blends in legislation: Work 20 years ahead: For 2030 fuel mix: 2020 vehicles should be suitable start development legislation in 2010 Well to wheel study on # criteria: climate impact, energy efficiency, land use efficiency, fuel costs, infrastructure, vehicle adaptation (possibly in cooperation with industry) 26