MIT OpenCourseWare http ocw mit edu 2 61 Internal Combustion Engines Spring 2008 For information about citing these materials or our Terms of Use visit http ocw mit edu terms Bio fuels and hybrids Prof Wai Cheng Sloan Automotive Lab MIT 1 The backdrop 2 Transportation and Mobility Transportation mobility is a vital to modern economy Transport of People Transport of goods and produce People get accustomed to the ability to travel 3 Transportation needs special kind of energy source Vehicles need to carry source of energy on board Hydrocarbons are unparalleled in terms of energy density For example look at refueling of gasoline 40 Liters in 2 minutes 0 25 Kg sec Corresponding energy flow 0 25 Kg sec x 44 MJ Kg 11 Mega Watts Liquid hydrocarbons 4 What is in a barrel of oil 42 gallon oil 46 gallon products Typical US output Lubricants 0 90 Other Refined Products 1 50 Asphalt and Road Oil 1 90 Liquefied Refinery Gas 2 80 Residual Fuel Oil 3 30 Marketable Coke 5 00 Still Gas 5 40 Jet Fuel 12 60 Distillate Fuel Oil 15 30 Finished Motor Gasoline 51 40 Source California Energy Commission Fuels Office 5 US Use of Petroleum by sector Millions of Barrels day 25 Electric utilities Commercial Residential 20 15 Industrial 10 Transportation 5 0 1970 1980 1990 2000 2010 Year Source US Dept of Energy 6 Oil Supply annual average up to 2007 100 Million Barrels day 90 80 70 60 Others 50 40 30 20 OPEC 10 US 0 1960 1970 1980 1990 2000 2010 Year Hubbert peak Source EIA 7 The world Hubbert peak excluding OPEC Russian production 2003 Image removed due to copyright restrictions Please see Fig 9 in Zittel Werner and J rg Schindler Future World Oil Supply Salzburg Germany International Summer School on the Politics and Economics of Renewable Energy July 2002 Source http www fossil energy gov programs reserves npr publications npr strategic significancev1 pdf 8 Petroleum price Decrease in demand increase in non OPEC supply 120 00 100 00 Saudi increase production Constant 2004 Barrel of the day 80 00 6 6 08 118 Barrel Iran Iraq War Iranian Revolution Yom Kippur War Arab Oil Embargo 60 00 40 00 2008 av value up to June Gulf War 20 00 Iraq war Demand of emerging market limited refinery capacity 0 00 1860 1880 1900 1920 1940 1960 1980 2000 9 11 Oil from North Sea Alaska Sources Data from EIA event labels from WTRG Economics 9 CO2 emissions from fossil fuel Million metric tons of Carbon year 104 8000 7000 103 6000 Total 5000 Total 4000 3000 102 Liquid fuel 2000 Liquid fuel 10 1000 0 1750 1800 1850 1900 Year 1950 2000 1 1750 1800 1850 1900 1950 2000 Year Source EIA 10 The drive to bio fuel Increasing demand of liquid fuel for transportation Population Society affluence Drive for lower CO2 production Perceived decline of petroleum reserve Fuel price Government Policy Tax credit Required bio fuel content 11 What is bio fuel 12 Dominant biofuels Sugar based corn sugarcane Cellulosic based switchgrass wood Crop based rapeseed soybean Wasted oil animal fat Usage Ethanol E10 E20 E85 Compatible with current engine technology and fuel infra structure Bio diesel B10 B20 Algae BTL fuel not included in this discussion 13 Example Ethanol production from corn Ethanol fuel Resources Energy Materials Ethanol CO2 Labor Sugar Purification removal of water Fermentation Starch Corn By products 14 Example bio diesel production Bio diesel esters Resources Energy Materials Labor Purification removal of glycerol alkaline fatty acid Esters and glycerol Transesterification using alcohol methanol with alkaline catalyst Oil tri glyceride Mechanical or solvent hexane extraction water removal Soy rapeseed Tri glyceride Alkaline Catalyst KOH Esters Glycerol CH2 OOC R1 R OOC R1 CH OOC R2 3ROH R OOC R2 CH2OH 2 CHOH CH2 OOC R3 R OOC R3 typically 8 22 C to 2 O 15 Combustion characteristics of bio fuel Diesel Soybean oil methylester Rapeseed oil methylester Sunflower oil methylester Frying oil ethylester Cetane number s g LHV MJ kg LHV MJ L B10 LHV MJ L 45 55 50 9 52 9 49 61 0 820 0 885 0 882 0 880 0 872 43 22 37 01 37 30 38 53 37 19 35 44 32 76 32 90 33 91 32 41 35 17 35 19 35 29 35 14 s g LHV MJ kg LHV MJ L E10 LHV MJ L 34 32 21 12 33 00 Octane number Gasoline Ethanol 95 107 0 780 0 785 44 00 26 90 B20 LHV LHV B10 LHV B20 MJ L Diesel Diesel by by vol vol 34 91 34 93 35 14 34 84 0 992 0 993 0 996 0 991 0 985 0 986 0 991 0 983 E85 LHV LHV E10 LHV E85 MJ L Gasoline Gasoline by vol by vol 23 10 0 962 0 673 Bio ester data from Graboski and McCormick Prog Energy Comb Sc Vol 24 1998 16 Stoichiometric requirement for different fuels 18 A F stoiciometric 16 Gasoline and diesel Gasoline with 11 MTBE O C 0 14 O C ratios of bio diesel esters 0 12 B100 12 Gasoline with 10 Ethanol 10 Ethanol E85 O C 0 5 8 O C 1 6 Methanol 4 2 1 1 5 2 2 5 3 Fuel H to C ratio 3 5 4 17 Relative CO2 production from burning different fuel molecules Image removed due to copyright restrictions Please see Amann Charles A The Passenger Car and The Greenhouse Effect SAE Journal of Passenger Cars 99 October 1990 902099 C Amann SAE Paper 9092099 18 Effects of Oxygenates on PM emission 100 Methanol 80 60 100 Dimethyl ether DME 100 Ethanol Water Diesel emulsion 15 to 20 water 40 100 Rapeseed methyl ester RME 20 Soot reduction 100 0 0 Diglyme methylal added to diesel fuel 6 to 14 wt 10 20 30 40 50 Fuel oxygen content Figure by MIT OpenCourseWare AVL Publication by Wofgang Cartellieri in JSME 1998 Conference in Toykyo 19 Bio fuel combustion properties Bio diesels and ethanol are fundamentally clean and attractive fuels to be used in engines The use of these fuels as supplements to petroleum base fuel are compatible with current engine configuration and fuel infra structure Practical issues can be adequately handled by engineering Fuel quality Engine calibration Materials compatibility viscosity Burning the fuel is the least of the problem 20 Status of bio fuel production 21 World liquid fuel production 2005 HYDROCARBONS RENEWABLES Image removed due to copyright restrictions Please see p 2 in Budny Daniel The Global Dynamics of Biofuels Brazil Institute Special Report Washington DC Woodrow Wilson International Center for Scholars April 2007 22 Millions of barrels per day oil equivalent Liquid fuel supply projection 120 100 80 60 40 20 Source ExxonMobil JSAE meeting Kyoto July 23 26 2007 0 1980 1990 2000 2010 2020 2030 23 US bio fuel capacity US biofuels US harvested crop land US agriculture census 2002 hectare 1 23E 08 US all distillate use diesel jet power gen etc EIA2007 L yr 3 34E 11 US