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Ethanol blends and flexible fuel vehicles -
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| Dr. T. R Jagdeesan, Emeritus Professor, Anna University, Chennai |
ABSTRACT
It has been estimated that nearly half of the current non-renewable petroleum demand equivalent to about 20% of the world’s energy consumption is being used by 550 million automobiles. This clearly indicates that the vehicles form the predominant source of regulated and unregulated pollution. It has been established beyond doubt that the tail pipe emissions contribute significantly to climate change. The vehicle population continues to increase exponentially and by the year 2010 about 1.1 billion cars are expected to be in use in the world. Unregulated Carbondioxide emissions, a prominent green house gas, will increase by 65% over the current levels due to large scale use of fossil fuels. To bring down drastically carbon emissions and sustain them over a period of time require a change in the concepts of production and use of transportation vehicles. Tremendous advances have been made in the development of power trains of modern cars which consumes half to one third the amount of fuel producing 90% less tail pipe emissions compared to automobiles in use two decades ago. However there is an urgent need to address the problems of depleting fossil fuel sources and increased green house gas emissions. Attempts are being made at international level to address these issues and among other possible solutions, the use of Biomass Ethanol needs special attention especially for a tropical and agriculture based country like India. Its use as a transportation fuel has been widespread in Brazil and it is becoming popular in USA. Ethanol can be derived from different sources of biomass such as sugar cane molasses, beats, corn, sorghum, potatoes and others. The effective use of Ethanol either as a neat fuel or as a mixture with gasoline has been proved to be technically feasible and environmentally acceptable for quite sometime. Some of the issues involved and strategies to be developed for the effective utilization of Ethanol as a fuel in the transportation sector in India with special reference to the desirability of developing Flexible Fuel Vehicles as a long term objective for controlling environmental degradation due to tail pipe emissions are presented and discussed. Short-term measure will include early introduction of Gasohol (90% Gasoline + 10% Ethanol) as a motor fuel for eliminating TEL and reducing aromatics in petrol.
India spends huge reserves of foreign exchange every year for importing crude and petroleum products. Sometimes it exports Molasses, which can be used to produce Ethanol fuel to meet the needs of our transportation sector. Based on experiences in Brazil and USA, India can develop a sustainable and viable Ethanol fuel program.
INTRODUCTION
India is the second largest producer of sugar cane in the world with a production level of about 280 Million tonnes per annum. Brazil, the number one, produces about 320 Million tonnes of sugar cane in a year. India stands fourth in the world in Ethanol production with a production about 1.3 Billion litres per annum. Brazil, which produces about 16.1 Billion litres per year, stands at the top of the table. USA is next with 5.75 Billion litres and China with a production level of about 2.83 Billion litres occupies the third place. The installed capacity in India is about 2.7 Billion litres per annum in 278 distilleries; thus we utilize only 50% of our capacity in ethanol production. Another significant feature relates to the use of Sugarcane produced in India. Only about 60% of sugarcane produced are processed for producing white sugar in 416 sugar mills located in different regions of India. 30% of sugarcane is used for making Gur and Khandasari sweeteners widely used in rural areas of India. The remaining 10% are used as seed. The Ethanol or Ethyl Alcohol production in India is mainly from Molasses the waste product from sugar mills unlike in Brazil where a substantial portion of sugarcane (nearly 60%) is converted into sugarcane juice, which is used directly to produce fuel ethanol. The sugarcane used for producing Gur and Khandasari does not yield Molasses the raw material for Ethanol. On a world wide basis out of the total annual production of 33.3 Billion litres of Ethanol 68% is used as an automotive fuel, 21% is utilized for industrial purposes and the remaining 11% is used for beverages. In India the entire production of Ethanol is used for industrial purposes and for producing beverages. We are yet to decide about utilizing Ethanol as a fuel in the transportation sector. Brazil has promulgated a Federal law which makes it compulsory to use 26% of Anhydrous alcohol (Ethanol) as a mixture with gasoline (76%) in all Spark Engine powered automobiles. Brazil also has a unique ALCOOL Program, which envisages the use of nearly 100% hydrous alcohol (Ethanol) with a very small amount of gasoline added as a denaturant. The USA is emerging as an important user of Fuel Ethanol for automotive applications. In this case Ethanol (Ethyl Alcohol) is primarily produced from corn. The technological options and the strategy to be adopted for developing an Ethanol Fuel Program in India are discussed in the following sections.
PREVIOUS WORK ON ETHANOL AS A FUEL IN INDIA
The interest shown in the use of Ethanol as an automotive fuel in India has been rather sporadic in nature and was largely related to crisis management situations. Very early reported work was carried out in Indian Institute of Science, Bangalore in 1950s soon after the Second World War. Substantial interest was shown in this area during the end of 70s and the beginning of 80s on account of steep rise in crude prices. Almost all the National level technical institutions and Technical universities
Embarked on Research and Development work pertaining to the use of Ethanol in gasoline and diesel engines used in Agricultural and Transportation sectors. The author himself was involved in conducting investigations in Anna University, Chennai on fleet tests using two models of SI Engine driven cars available at that point of time (during 1979-1984). These vehicles were converted to run either on 100% Ethanol (denatured Alcohol) or with a mixture of 90% gasoline and 10% ethanol (gasohol). C.I.Engines (Diesels) were run on dual fuel mode using a carburetor. It was possible to operate Passenger buses on dual fuel mode with 45% diesel replacement under dual fuel operation. The investigations enabled the collection of valuable data on optimal modifications necessary for converting an existing S.I.Engines for neat ethanol operation. Long duration trials yielded valuable data on material compatibility and lubricating oil requirements for ethanol operation. Emission measurements showed considerable reduction in conventional pollutants like CO, HC, and Nox during ethanol operation. However there was an increase in the Aldehyde emission levels. The interest in such investigations dwindled, as there was neither clear-cut Government policy nor a direction for use of Ethanol as a fuel in the transportation sector. In view of this the Automotive and Sugar Industries did not support such developmental works. Nevertheless the data obtained and the experience gained have been well documented and can be used for future investigations. Of the many important conclusions drawn from such studies the one which is very relevant to the present discussions pertains to development of dedicated Ethanol Vehicles. The Ethanol production and distribution depends on several factors and one should learn from set back witnessed in Brazil’s ALLCOOL Program. When an automobile is running on dedicated mode, that is it can run only with fuel ethanol, it is incumbent on the part of the fuel supplier to ensure unlimited and uninterrupted supply of the fuel. Such a vehicle cannot operate on gasoline. If we compare the properties of the fuels (Table I) it will be apparent that Alcohol fuels do have some desirable properties compared to gasoline. They also have some undesirable properties, which needs to be taken care of. The use of a mixture of gasoline and ethanol such as E85 in different proportions in Automobiles is likely to become very popular in future. There is a trend to develop Flexible Fuel Vehicles, which can operate on different ratios of Ethanol and Gasoline. It is desirable to discuss about the features of FFVs and look at the possibility of developing such vehicles in India.
FLEXIBLE FUEL VEHICLES
Two specific pieces of U.S. Federal Legislation, the Clean Air Act of 1990 and the Energy Policy Act of 1992 mandated the phased in adoption of less polluting automobiles in that country. Under these federal laws, state, municipal and private fleets must meet stricter emission guidelines starting from the year 1998. Indeed this Legislation among other things enabled leading automakers to bring out different types of Alternate Fuel Vehicles popularly known as AFVs. Flexible Fuel Vehicles M85 and E85 come under this category. By the year 2000 nearly 70% of all new fleet vehicles are expected to meet these new standards and automobile.
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Manufacturers are gearing up to meet these new requirements. It is believed that FFVs will form a significant portion of the total number of AFVs that may be introduced. Many states have shown a keen interest in the use of ethanol blended gasoline popularly known as E 85. Vehicle using E 85 fuel are capable of operating on a mixture of ethanol and gasoline upto a maximum of 85% ethanol the remaining 15% being unleaded gasoline. The small percentage of gasoline enhances starting in cold weather and also acts as a denaturant. If the vehicle is designed to operate in flexible fuel mode then it can operate from 0% ethanol and 100% gasoline to 85% ethanol and 15% gasoline. An alcohol fuel sensor (a capacitor type or an optical type) detects the percentage of ethanol in a mixture of ethanol in the mixture and provides a signal to an on-board computer (ECU) which optimizes ignition timing and air/fuel ratios.
Almost all the major automobile manufacturers in USA, Japan and South Korea have come out with Flexible Fuel Vehicles to run on M85 or E85 fuel. The three Majors namely General Motors Corporation, Ford and Daimler Chrysler have come out with FFVs using E85. Ford has introduced two models Ranger and Taurus which can run on this blend. (Annexure-I). Daimler Chrysler has three models with to run on E85 viz. Town and Country, Dodge Caravan and Plymouth Voyager.
(Annexure II) The GMC has three models which can operate on E-85, the ChevyS10, Sonoma and Lumina. (Annexure III). All of these models have been extensively tested for emission levels as per EPA regulations and most of them have been classified as Transitionally Low Emission vehicles (TLEV). Many of the Japanese automobile manufacturers such as Honda, Mitsubishi, Nissan and Mazda have developed their own versions of FFVs. While the results of considerable experience gained in running neat Ethanol vehicles in Brazil are available attempts are being made in USA to obtain further data from programs like 1998 and 2000 Ethanol Vehicle Challenge. This program is a part of a series of Advanced Technology Competitions sponsored by the US Department of Energy. The Cosponsors of this program are GMC and a host of R & D organizations. Under this program students from 14 technical institutions and universities are permitted to convert a stock Chevrolet Malibu car from gasoline operation to dedicated operation on Fuel Ethanol also known as E85( 85% denatured Ethanol + 15% gasoline like hydrocarbon primer ). Each school participating in the 1998 Ethanol Vehicle Challenge received a GM Malibu car, a spare engine and an ethanol compatible fuel pump from GMC. Number of industries and organizations sponsored individual schools. The main challenges student faced were fuel economy, cold starting and emission levels. These programs enabled new ideas to be generated. The results obtained and data collected in such competitions enable all concerned to implement viable and practical ideas. It is reported that the majority of vehicles met the US Federal Tier 1 emissions standard.
The prices of most of the FFV models are almost the same as that of a stock gasoline version or about US $ 500/- more. A litre of E 85 ethanol fueled vehicle should get about 2/3 the energy of a litre of gasoline. The E 85 cars should get about 2/3 the fuel mileage of the gasoline version of the vehicles. However it is found that Ethanol cars found to get 5-10% above what was expected due to superior characteristics of ethanol fuel. Repairs and reliability of E85 FFVs have been found to be better than gasoline counterpart. In US the price of E85 Ethanol fuel is about the same or slightly less than the price of gasoline due to tax incentives offered by the different states.
CONCLUSION
It has been established that the use of Ethanol as a Fuel in Transportation Sector reduces both Green House emissions (CO2) and fossil energy use. This is due to the fact that the ethanol feed stock, in our case Sugar Cane, absorbs Carbondioxide emitted by automobiles. Conventional regulated emissions such as CO, HC and NOx have been found to be well below prescribed levels. The Technology for adopting Ethanol as a renewable fuel in the transportation sector is readily available and can be quickly put into practice as all the leading FFV manufacturers have opened manufacturing facilities in India. To start with we can utilize straightaway E 10 fuel ( 10% Ethanol + 90% Gasoline) dispensing the use of TEL and aromatic compounds for maintaining acceptable octane number levels. No major engine modifications are necessary for this change. The Government, the Automobile Industry, the Sugar Industry, the Ethanol Distillery Industry and the Oil Companies should jointly evolve a strategic plan to launch a viable Ethanol fuel program in India in a phased and sustainable manner so as to keep the regulated emission under control and to minimize the green house gas emissions. The Government and the Industries should encourage technical institutions to participate in joint R&D Programs such as the Ethanol Vehicle Challenge in USA to generate new ideas and to design systems suitable to Indian conditions. In the long run develop a suitable FFV program for utilizing larger percentages of Ethanol in the mixture as it will take a considerable time and effort for establishing a reliable distribution network for Ethanol in India such as the one available in Brazil. The formation of Ethanol Coalition in India will go a long way in bringing together people and enterprises that are interested in implementing a viable program of using a renewable fuel for the transportation sector in India. The possibility of using Ethanol in a dual fuel mode or in conjunction with additives as a mixture of Diesel and Ethanol in Diesel Engines should be explored. However the success of such alternative fuel program in India will depend on our ability to develop mechanisms which will ensure uninterrupted supply of this renewable fuel
