1.10.2010 | printed in the Winter 2010 issue of VITAL magazine
The vision of an engine powered by ethanol is nearly as old as the days when a car was referred to as a “horseless carriage.” In 1896 Henry Ford built his first automobile, the quadricycle, to run on pure ethanol. The first flexible fuel vehicle, running on gas, ethanol or both, was introduced to the market in 1908 with Ford’s gamechanging Model T.
While Ford believed in alcohol-based fuels like ethanol, and is even quoted as calling it the “fuel of the future,” political and economic challenges would force ethanol to take a backseat to petroleum in the years to come.
The increasing need for “anti-knock” gasoline led Sir Harry Ricardo, a pioneer in the development of the internal combustion engine, to carry out research in the 20s and 30s that became the forerunner of today’s octane rating scale. The higher the octane rating, the slower the fuel will burn and the less likely the engine will knock.
Ethanol enjoys a very high octane rating of 113. When blended with gasoline, the octane rating of the fuel goes up improving the fuel’s performance. In addition, ethanol adds oxygen to the fuel mixture so that it burns more completely and cleanly, reducing harmful tailpipe emissions.
However, the introduction of large supplies of cheap foreign oil and domestic oil field discoveries made gasoline less expensive than ethanol. The rise of the powerful oil companies contributed to a slow down in ethanol use.
But then in the 70′s, words like “smog” and phrases like “oil crisis” entered the vocabulary of Americans and there was renewed interest in the benefits of ethanol. And by the mid-eighties, nearly all automakers made sure that engines could efficiently use the E10 blend. Today, approximately 70 percent of all gasoline sold in the United States contains some ethanol. The majority is E10, but you will also find E85.
Flex Fuel Vehicles (FFV) have been manufactured to run on E85. FFVs engines are the same as regular engines, except they have the ability to use straight gasoline or tolerate ethanol blends of 85 percent and anything in between. Tolerate being the key word, but what if you made a flex-fuel engine that was designed to take full advantage of ethanol’s best properties — high octane and high heat of vaporization — to actually improve the performance of the engine?
SAY HELLO TO EBDI
The Ethanol Boosted Direct Injection (EBDI) engine developed by Detroit, Mich. Based Ricardo, Inc. (Yes, it’s the same company founded by Sir Harry Ricardo but formerly called Engine Patents, Ltd.) surpasses gasoline engine efficiency and approaches performance levels previously reached only by diesel engines.
“The combination of technologies we’re applying to the EBDI engine make the most of ethanol’s advantages over other fuels, which include a higher octane rating and a higher heat of vaporization. Without getting too technical, this means we can use a high level of turbocharging to achieve the high cylinder pressures that ethanol enables. Add in some other advanced technologies such as direct injection, variable valve timing, optimized ignition and advanced exhaust gas recirculation, and we’re squeezing out more power than is possible with gasoline,” says Rod Beazley, Director of the Ricardo Inc Gasoline Product Group.
“The EBDI engine is optimized for flex fuels. E0 to E85, even E100. The complete spectrum. There’s a difference between heating E85 and E0 that affects the miles per gallon. We are closing that gap with technology. It would be the ideal application for blender pumps,” Beazley adds.
By the fall of 2010, Ricardo, in partnership with Growth Energy, will have two demonstration vehicles by converting GMC’s Sierra full-size 6.6 liter diesel engine pickup with the 3.2 liter ethanol fueled EBDI engine.
“The engine is less than half the size of the previous engine and makes the same torque performance as the diesel engine in terms of trailer/ towing capability and better power performance,” adds Luke Cruff, Ricardo Chief Engineer.
“The newly developed engine has over-achieved its low speed torque performance goals on both ethanol and gasoline. This represents an archetypal change when considering the low speed torque output of the gasoline engine compared to the diesel engine — the gasoline engine far out-performs the diesel in terms of specific torque performance, or brake mean effective pressure (BMEP),” says Beazley.
Rod Harris, Ricardo Chief Engineer explains the goal, “We want to demonstrate the capabilities of ethanol in a full-size pickup because the technology we are developing is scalable. It can be used in medium duty applications up to a 6 or 7 class truck. Or it could be scaled down to a small vehicle. You could put a 1.4 liter version of this in a mid-sized car and still get the same performance of the V6 that is currently in there… or better. Not to mention additional applications such as garbage trucks, school buses, agriculture and construction.”
“In production, the EBDI would enjoy a cost advantage in the order of $3,000 – $5,000 per vehicle,” says Beazley. “This advantage is a result of EPA emissions legislation to clean up the diesel’s dirty exhaust. The legislation isn’t applicable to EDBI because it basically runs as a traditional gasoline engine with the same gasoline engine after-treatment.”
“It uses a traditional three-way catalytic converter for after-treatment. The same as everybody’s car does today,” Cruff says.
Additionally the technology requires only a single direct injector per cylinder as opposed to the more complex and costly dual injection (DI – PFI) options that are also currently under development.
“The thing about the EDBI project is that it takes a lot of known or current technologies, or at least technologies that are fairly well along in development, so turbos, direct injection, exhaust gas recirulation (EGR) and puts them all together in a package that’s a little bit different than it has ever been done before. The biggest challenge this presents is actually in the control system.” But Cruff continues to add that, “There’s no major technological breakthroughs that have to be done. It’s really learning what kind of controls need to be developed to enable all of the performance characteristics of the engine. It is nothing that’s too Star-Trek-y.”
“The greatest immediate challenge EBDI technology must overcome is the comfort level engine builders and customers have with diesel,” says Vice President of Business Development for Ricardo, John Pinson. “For many applications, the practical benefits for engineers and operators will be hard to ignore.”
“Our target on E85 is about 15 percent higher torque and power over the gasoline engines. So that right there is a significant incentive for the operator, the driver of the truck to put ethanol in the truck. If he wants full performance out of the truck, then he’ll have to put ethanol in it. That’s a complete step change from how most people are doing flex fuel vehicles today,” comments Cruff.
Harris says, “The whole package is being put together so if a manufacturer came tomorrow and said they wanted to start implementing the technology, we’d be able to have it in production by 2014 or 2015. It’s not a long-term research project. It’s really something we really see being viable within the market place with the next 4-5 years.”
Rod Beazley’s sums up the EBDI engine quite nicely as “the possibility to transport America’s future using ethanol.”
While Ricardo’s EBDI engine is a complete replacement of today’s engine, a new venture in Laurel, Nebraska has come up with a solution that makes it possible to burn ethanol in existing diesel engines. The retrofitting technology was created by CleanFlex Power Systems, LLC.
“There are over 60 million vehicles right now on the North American continent that could use this technology,” says Kevin Kenney, BioFuel Systems Engineer for CleanFlex who began working on this project in 2004 and has been involved in biofuel research for over twenty years.
HOW IT WORKS
Ron Preston, CleanFlex President, says the fuel they are using is 120 proof ethanol. It’s a mixture of 60 percent ethanol and 40 percent water. It is not blended with gasoline.
The system requires two separate tanks, one for the ethanol-water mixture and the other for the diesel. The fuel mix in the engine is 85 percent diesel and 15 percent 120-proof ethanol, but the ethanol ratio can be adjusted higher.
“An advantage of the CleanFlex system is it allows for an individual to have two different types of biofuels, you can use blended biodiesel (B5 or B20) and in the other tank you can use 120 proof ethanol,” explains Kenney.
“What we’ve done is integrate prior research into a very sophisticated electronic control system. In fact, we are using the latest technology from the racing arena.”
Kenney continues, “Diesel fuel is metered into the engine through mechanical or electronic control systems. The new diesel engines are all electronic. CleanFlex can work with both of them. When the diesel engine needs to have emissions lowering additive, which is the 120 proof ethanol, we electronically program that ratio of ethanol versus diesel. It is very fail safe and it’s a patented process.”
“The only time the ethanol, water and diesel come together is in the combustion cylinder,” adds Bob Dickey, Chairman of the National Corn Growers Association and Chairman of CleanFlex. “The end result is the engine runs cooler and more efficient. Plus the emissions have been reduced.”
“In fact, tests have proven this technology lowered emissions of NOx approximately 47 percent. This toxic emission causes smog which is a human health hazard. Particulate matter (PM) another toxic health hazard, we believe was also reduced approximately by 20 percent,” says Kenney. The fuel and retrofit option couldn’t have arrived a more opportune time with new EPA Tier 4 emissions standards that will soon go into effect.
One option out there to satisfy the new standards is to use SCR (Selective Catalytic Reduction). But as Kevin points out, “We have a biofuel driven solution that rivals SCR. There is virtually no infrastructure for SCR right now. We have the solution right under our nose with the infrastructure of ethanol.”
CleanFlex has just finished up the testing phase and have started to go into installation. Preston says they are ready for commercialization right now and estimates the cost to retrofit an engine or vehicle will be around $5,000 -$7,500 depending on the application.
“But nearly all old diesels will need some modifications in order to meet the new EPA standards that will be phased in over the next few years,” adds Preston. “The fact that farm diesel engines may soon be affected is a definite possibility.”
It’s also important to remember that this cost needs to be spread out over the lifetime of the vehicle.
Currently, CleanFlex is working with the EPA and also CARB (California Air Resources Board) to achieve accreditation as a certified/verified technology within the national clean diesel campaign.
Regardless if the innovations in engine technologies come from a farm in Nebraska, the racing track in Florida or a technical center in Michigan, one thing is certain – the future of ethanol and the engines that take advantage of its best properties, have a bright and long road ahead. It looks like Henry Ford’s prediction of ethanol as the “fuel of the future” is proving to be true.
Maximizing Efficiency. Minimizing Impact
By Julie Flannery-Allen