The Dawn of the Hybrid Class-8 Truck
But because many trucks travel every single day, during almost every hour of the day, everywhere in the world, there’s a growing concern about the emissions from such vehicles and the harm they present to climate change. In addition, fuel costs are a significant concern for any operator who seeks to operate in the most economically advantaged way.
Alternatives to Electric Power
These concerns have given rise to the development of electric vehicles and hybrid vehicles. Electric vehicles always present two notable concerns: can they develop sufficient power to transport goods, and can they provide trucks with a sufficient range of travel before needing recharging. This is particularly troublesome because the nation does not have an adequate and dispersed charging infrastructure.
But what is the viability of hybrid heavy class 8 trucks? Hybrid technology would allow both fuel consumption (via diesel fuel or other) and electric propulsion.
Researchers at MIT have devised a plug-in hybrid system. [https://www.eurekalert.org/pub_releases/2019-04/miot-edc040819.php] It’s an innovative way of powering trucks just as hybrid vehicles are powered. Hybrid vehicles could drastically curb pollution, increase efficiency, and reduce or even eliminate their net greenhouse gas emissions.
Flex-Fuel for the Hybrid Alternative
MIT’s proposed technology would be used for a truck primarily powered by batteries. With a spark ignition engine in lieu of a traditional diesel engine, the truck would travel equivalent distances as conventional commercial diesel trucks. These new designs would “flex-fuel” models: they may run on gasoline, alcohol, or other blends of fuel.
However, the goal is to power the trucks with battery power. The flexible fuel provides options for different types of fuel. The power generated by the flexible fuels would charge a battery bank when idling and while moving. Thus, the fuel power supplements the battery power. Battery power, of course, entails no emissions and exhaust and is therefore environmentally friendly and sustainable.
For truck owners, the emissions requirements are most compliant, and their fuel bills are likely to decrease. The trucks are now ready and available to burn alternative fuels, which may be less expensive, provide more fueling options, and in some cases, cleaner burning.
While the goal would be to power trucks entirely with batteries, the researchers say this flex-fuel hybrid option could provide a way for such trucks to gain early entry into the marketplace by overcoming concerns about limited range, cost, or the need for excessive battery weight to achieve longer range.
Tesla Motors planned to introduce an all-electric heavy-duty truck; however, researchers at MIT say an electric design to provide needed power requires batteries that add weight and are also costly. Often, they use lithium-ion batteries that are costly and sometimes dangerous. In addition, the battery requirement would add nearly 10 to 15 tons of weight.
The flex-fuel configuration is a notable advantage as it allows them to run on pure methanol or ethanol. Such fuels are derived from renewable sources such as agricultural waste or municipal trash. This flexibility is a good thing and one that owners will benefit from as they not only can draw on renewable sources as well as non-renewable sources such as fossil fuel-based sources such as diesel or gasoline, but there are numerous options to choose from. Many fuels reduce pricing and supply risks and help the truck owner stay environmentally compliant—not to mention the benefit of added efficiency from the hybrid arrangement.
The engine the MIT researchers designed uses such a hybrid and is highly efficient with the lighter flexible-fuel. They say it produces one tenth of the air pollution as diesel-powered vehicles.
“Over time, gas engines have become more and more efficient, and they have an inherent advantage in producing less air pollution,” explains Leslie Bromberg, one of the MIT researchers. “By using the engine in a hybrid system, it can always operate at its optimum speed, maximizing its efficiency.”
Dave Cohn, another of the MIT researchers, says the ultimate benefit remains to be determined: “We don’t know which is going to be stronger, the desire to reduce greenhouse gases, or the desire to reduce air pollution.” In the U.S., climate change may be the bigger push, while in India and China air pollution may be more urgent; regardless, “this technology has value for both challenges.”