By Brendan Baker, senior editor
Engine Builder magazine
Currently gas prices have stabilized at around $1.83 a gallon, a price at which most Americans feel comfortable driving their SUVs, trucks, race cars, tow vehicles and other motorized toys. But when gas hits $4 and $5 a gallon, driving guzzlers becomes a challenge for many.
It was only a few months ago that a barrel of crude oil was well over $100, a price that seemed to embed itself into the minds of most of us as we drove to wherever we were going. It felt like we ate a big triple scoop of ice cream way too fast as our wallets and gas monster SUVs were forced onto extreme diets.
This petroleum problem is nothing new. Every generation or so we revisit other ways to transport ourselves from place to place but by and large we stick with the old tried-and-true internal combustion engine. As engine builders, our livelihoods depend on this form of propulsion. But what, if anything, can we do if this were to change?
Ever since gas topped out at $5 a gallon, there has been a steep increase in the number of vehicle owners interested in converting their engines to run on alternative sources of fuel. The desire to lessen environmental impacts and reduce oil dependence has ramped up interest in alternative fuels and green technologies. Although reasons vary for changing over to alternative fuels, the fact remains that engine builders could carve out a nice market for themselves by specializing in conversion systems.
Variety of Alternative Fuels
There are many types of alternative fuels available. Ethanol, biodiesel, and natural gas offer the most potential to engine builders who want to get in on the green movement without completely giving up on what they already do. While there are different materials and processes used to build these types of engines, for the most part, these engines are pretty straightforward internal combustion units.
Another factor engine builders can look at is how to market their services for these types of builds. Chances are that most of your business for conversion systems will come from a company with a fleet of vehicles, whether it’s of school buses, postal trucks or even golf course, farm equipment or other types of specialty vehicles. There are also opportunities in building specialty performance “hot rod” engines for use with ethanol.
Ethanol is a clean, environmentally friendly fuel and in an 85 % blend, it is very clean and even more environmentally friendly. E85 reduces harmful hydrocarbon and greenhouse gas emissions.
E85 is the highest performance fuel you can purchase at the retail level with its octane rating of at least 105. Because E85 vehicles are flexible by nature, owning a flexible-fuel vehicle (FFV) is a practical way to enter the world of alternative fuels without any limitations on the vehicle’s range.
Availability of E85 is improving but is still limited in most markets. There are currently about 1,750 stations in the United States offering E85, compared to nearly 200,000 gasoline retailers in the United States. While there is still a large disparity, building the necessary infrastructure to meet additional E85 demand is not overly complicated.
Ethanol is a liquid fuel stored primarily in underground tanks and dispensed through a pump, hose and nozzle just like gasoline. Unlike some motor fuel alternatives, the experience of fueling with E85 is no different than filling up with gasoline.
Ethanol is a clean, renewable, high performance fuel for your engines. Ethanol blends up to 10 % (E10) can be used without any engine or fuel system modifications. E85, which is 85 % ethanol, 15 % gasoline) is for use in FFVs, which run on gasoline or any blend of ethanol up to 85%, or engines and vehicles specially tuned to run on ethanol. Many recommend its use because of its high octane and superior performance characteristics.
Ethanol is currently blended into about 70 % of U.S. gasoline, the majority as the E10 blend. Each state determines whether gasoline needs to be labeled if containing ethanol, so if you’re in an area where labeling is voluntary or not required, it is not always possible to tell if the gasoline contains ethanol. Ethanol blends are offered extensively throughout the Midwest and are becoming more available in the rest of the country.
Because ethanol has an octane rating of 113, adding 10 % ethanol to gasoline raises the finished fuel’s octane rating by 2 or 3 points, improving the fuel’s performance.
Some engine builders have found that E85 is a good platform for building high performance street engines that run solely on ethanol and pump out big horsepower.
One expert said that the problem with FFVs is that they are a compromise in terms of efficiency on ethanol. These engines are not built to take advantage of the higher octane of ethanol, though they do run fine on both fuels. Engines designed to run solely on ethanol need to take into account the extra fuel requirements. Carburetors will need to be re-jetted and tuned and fuel injected engines will need larger injectors and upgraded ECU mapping. Due to higher compression ratios of these performance engines, they cannot run on pump gas but can make significantly more power with a properly tuned E85 engine.
Natural gas is a clean-burning alternative fossil fuel that can easily power internal combustion engine vehicles. An abundant supply of domestic natural gas makes it a highly attractive alternative fuel. Most propane vehicles are conversions from gasoline vehicles.
Dedicated propane vehicles are designed to run only on propane; bi-fuel propane vehicles have two separate fueling systems that enable the vehicle to use either propane or gasoline.
Propane-powered vehicles’ power, acceleration and cruising speed are similar to those of gasoline-powered vehicles. The driving range for bi-fuel vehicles is comparable to that of gasoline vehicles.
The range of dedicated gas-injection propane vehicles is generally less than gasoline vehicles because of the 25 % lower energy content of propane and lower efficiency of gas-injection propane fuel systems. However, Liquid Propane Injection engines, introduced in 2006, deliver fuel economy more comparable to gasoline systems.
Lower maintenance costs are a prime reason behind propane’s popularity for use in delivery trucks, taxis, and buses. Propane’s high octane rating (104 to 112 compared with 87 to 92 for gasoline) and low carbon and oil contamination characteristics have resulted in documented engine life of up to two times that of gasoline engines.
Because the fuel mixture (propane and air) is completely gaseous, cold start problems associated with liquid fuel are eliminated.
Compared with vehicles fueled with conventional diesel and gasoline, propane vehicles can produce significantly lower amounts of harmful emissions.
Biodiesel can be made from various sources including soybeans and biomass. Biodiesel can be used in most diesel powered cars without modification, however, it is more prone to be contaminated so it is often necessary to add extra filtering systems or change out filters more often.
Biodiesel can be used in any concentration with petroleum based diesel fuel in existing diesel engines with little or no modification. Biodiesel is not the same thing as raw vegetable oil; it is produced by a chemical process that removes the glycerin from the oil.
A common misconception of biodiesel is that it’s made only from soybeans. Soy is a good source and the most common crop for biodiesel in the U.S., but many other crops and plants including flax, mustard, rapeseed, sunflower, palm, hemp, jatropha, and pennycress can also be used. In addition, biodiesel can be made from animal fats and waste vegetable oil.
New clean diesel technology with complex and sophisticated aftertreatment exhaust systems make universal standards critical if manufacturers are to allow higher blends.
According to experts, the primary concern with higher blends of biodiesel isn’t with the quality or even energy content of the fuel, but its viscosity.
Modern clean diesel engines have very precise fuel delivery timing and metering, so a change in fuel viscosity makes this precise metering very challenging. In one combustion cycle, there may be as many as seven separate injections of fuel. This is one of the reasons why modern clean diesel engines are so smooth and quiet. Fuel delivery may include two pre-combustion injections, up to four main combustion injections, and even a small shot of fuel after the main combustion process for a more complete burn.
The American Society for Testing and Materials (ASTM) recently approved significant biodiesel specifications that should help acceptance of B20. In addition to changes in existing standards for B100 blend stock specifications and finished specs for up to 5 % biodiesel in conventional petrodiesel, a new third standard was adopted for blends between 6 % (B6) and 20 % (B20) biodiesel.
Along with the federal mandate for ultra low sulfur clean diesel fuel (below 15-parts-per-million sulfur content) manufacturers will now be assured the necessary standards to support higher blends of biodiesel with confidence.
So What’s Stopping You?
Availability and lack of infrastructure are some of the biggest issues with alternative fuel conversions. Also, the Environmental Protection Agency (EPA) and California Air Resource Board (CARB) have rules concerning the sale and conversion of alternative fuel systems.
The Environmental Protection Agency (EPA) has rules concerning the manufacture, sale and installation of alternative fuel engine conversion systems. In California, similar and even more stringent emission rules and guidelines have been established by the state’s Air Resources Board (CARB). These rules apply to both natural gas- and propane powered engine retrofit systems, and will presumably apply to ethanol and/or hydrogen retrofit systems if/when they are ever approved.
Only EPA and/or CARB-certified conversion systems are permitted to be installed on vehicles manufactured since 1994 (when EPA first addressed the issue of conversion systems). The EPA directive states that vehicles owners should use “reasonable judgement” and not do anything to diminish emissions performance on vehicles manufactured prior to 1994.
While a variety of non-certified systems are sold on the Internet and/or offered by some automotive shops, EPA has taken the position that installation of these systems is “tampering with a federally approved emission control system,” a federal violation punishable by a substantial financial penalty. Many of these non-certified systems are allowed in other countries that have less strict vehicle emissions and safety laws.
To obtain EPA and/or CARB certification for a specific engine or engine family, manufacturers of retrofit systems referred to as Small Volume Manufacturers (SVM) must submit a converted vehicle to EPA or CARB for rigorous testing along with substantial technical documentation. This testing ensures that the retrofitted vehicle meets the same stringent emissions requirements the OEMs met when they submitted their gasoline or diesel-powered vehicle for certification.
The testing also ensures that the retrofit system works seamlessly with the OEM’s on-board diagnostics (OBD) system to indicate when emissions are outside of approved parameters and to log those anomalies in the computer memory for downloading by the automotive service technician. Non-certified systems usually do not meet this important criterion and will fail state or local emissions tests.
The process of engineering, manufacturing, installing, pretesting and then submitting a proposed retrofit system to an EPA- or CARB-approved laboratory for certification is a time-consuming and expensive process that experts say can cost as much as $200,000 or more per engine family. SVMs recoup this R&D investment by amortizing the cost across the expected sales volume, adding it to the price they charge for the various components (computer control module, regulator, injectors, high-pressure hoses and fittings, etc).
A retrofit system certification applies to a specific engine for specific model year such as the 2008 GM 6.0L engine family, which applies to several but not all 2008 GM vehicles with a GM 6.0L engine. This certification applies only to the installation of that system for a limited time period. SVMs may carry-over their certifications into future years by filing additional documentation and paying a fee, allowing them to convert a previous model-year vehicle in later years. This decision to carry over a certification is usually based on the SVM’s projected sales volume.
Due to the technical difficulty and the expense, only a few SVMs have elected to go through the EPA- and/or CARB-certification process and, even then, only for a limited number of engine families and applicable vehicle models. Currently, there are only four SVMs offering EPA- certified systems (two have CARB certifications) for four GM and Ford light-duty engine families covering about twenty vehicle models.
These include the GM 6.0L engine and the Ford 4.6L, 5.4L and 6.8L engines. Currently, there are no natural gas engine conversion systems available in the U.S. for any other light-duty vehicle brands although American Honda does manufacture the natural gas Civic GX at its East Liberty, OH plant.
Installation of an engine conversion package and fueling system may be done after the vehicle has been in service or when the vehicle is first purchased. EPA and CARB require that SVMs provide appropriate documentation and training to installers of their systems, commonly referred to as qualified system retrofitters (QSR).
Installation by a non-qualified installer could damage the retrofit equipment or the engine (or both), compromise vehicle performance, or render the vehicle unsafe to operate. No EPA- or CARB-certified engine conversion systems are sold to untrained/unapproved installers. Some SVMs prefer to do these installations themselves while others opt to sell their systems only through QSRs. Typically, QSRs are responsible for obtaining the fuel storage system components such as cylinders, high-pressure tubing, pressure release device (PRD), brackets, protective plates, etc., and installing these components in accordance with fire and fuel systems code.
Engine builders and installers interested in becoming a QSR should contact the SVMs directly to inquire about the technical, equipment and financial capabilities/resources they require and the process to become one of their QSRs.
For engine builders looking for a way to go green, these fuels offer the most promise but currently some of the limitations may make it a challenge to build engines for some platforms. It is important to know what you can and cannot do from a legal standpoint. If you have concerns you should contact the EPA for more clarification. However, there is a market out there for these engines, which are not all that different from gasoline engines.
There is no single solution to our petroleum addiction. E85, biodiesel, natural gas, hybrids, other fuel saving technologies, hydrogen someday, plus viable alternatives to auto use for daily commuting all must be vigorously pursued, say experts. And for engine builders to survive you are going to have to learn the intricacies of each of these fuels to be successful in the future. And the future will be here much sooner than we think.