ETHANOL BOOSTED GASOLINE COMBUSTION MATCHES DIESEL EFFICIENCY
Ford is reportedly progressing with a technology initially for pickup trucks that is expected to increase gasoline engine fuel efficiency to the diesel level at much lower first cost. Information about the effort, code named BOBCAT, is attributed to Dan Kapp, Director of Ford Powertrain Research & Advanced Engineering in a published report by PickupTrucks.com
The target is further gain in fuel efficiency from Ford’s gasoline engine EcoBoost system that employs turbocharging and direct injection. The system is a development of MIT (Massachusetts Institute of Technology) engineers including the internationally recognized engine combustion authority, Dr. John Heywood and a group of associates at Ethanol Boosting Systems, LLC (EBS), Cambridge, Massachusetts. (www.EthanolBoost.com)
Higher than traditional Otto engine compression ratios of the system are made possible by direct injection of ethanol supplied from a separate fuel tank during periods of high engine torque to control detonation (knock). Since the onset of the use of gasoline (Otto) engines, lower compression needed for control of detonation at high power has limited overall efficiency. The specific compression ratio Ford will use and MIT has been testing is not given, however, EBS has indicated it will be “12:1 or higher”...
By direct injection of ethanol with its cooling effect and high octane rating, detonation is controlled during high power operation. This permits higher full time compression ratio with its greater efficiency with gasoline. EBS testing indicates that direct injection of ethanol (or E85) represents on average only about 5% of total fuel use and is expected to decline to 3% with refinement. The system effectively rewards drives who limit high power operation, hence, need refills of the ethanol boost fluid tank the least.
EBS explains that while only about 1% of gasoline stations now have E85 pumps, the number will expand and ethanol or E85 can also be readily distributed in 1 or 2 gallon packages the same as windshield washer fluid..
The EBS system is believed to also be attractive for use in heavy duty applications such as busses, refuse trucks and delivery vehicles and is expected to be in demand for all classes of cars and light trucks permitting smaller, lighter engines yet provide high power on demand. GM’s Bob Lutz recently said “in 5 to 10 years, the 4-cylinder will be the predominant engine”. Others expect to also see 3, 2 and 1 cylinder automotive engines in time.
Much lower cost of the EBS system compared with costly emissions controlled diesels reflects in part use of standard gasoline engine 3-ay catalyst control. The higher cost of hybrid electric systems reflects their electric component and complexity added to IC engines...
First use of the EBS system is expected to be Ford’s important pickup truck business hard hit by slumping sales due to high fuel prices and consumer expectations that more efficient models are coming.... Unknown at this time is the status of plans for other product lines at Ford and elsewhere but considering ethanol boost system economic and efficiency advantages and apparent modest needs for new engine plant tooling, the fundamental gains from higher compression engines may well prove to be another milestone in the convergence of Diesel and Otto technologies.
As an indicator of things to come back in 2005, asked at a University of Wisconsin conference on IC(internal combustion)engine technology about the outlook for large scale conversion of U S. car production to diesel, Dr. Heywood and a number of prominent executive engine engineers at the conference told this journalist that diesels were not expected to match diesel market penetration achieved in Europe. We now know .what Dr. Heywood, perhaps then, had already brought along in its development cycle.
This new use of ethanol coincides with emerging new methods for volume production of ethanol without use of food crops. U.S. Departments of Energy and Agriculture are actively investigating and supporting projects with this objective also driven by legislated large increases in ethanol motor fuel.production.. . .