Dual Fuel Engine
DF or Duel Fuel Engines are the type of engines that can work on a mixture of diesel fuel and gas fuel or it could operate on diesel fuel alone. Duel Fuel engines could not operate on gas alone as they do not posses an ignition system, nor do they possess any spark plugs.

As the engine is not a pure diesel engine and diesel is not a pure gas, this machinery does suffer from poor fuel efficiency and Methane slippage. Like for instance, the fuel efficiency could be 5% to 8% less than in a comparable spark-ignited, lean burn engine at 100 percent load. It could even be lower or higher loads.

Lift Truck Fuel Sources and Classifications
There are certain recycling materials handling applications that can prove very challenging for lift trucks. For example, scrap metal is among these problems. To be able to successfully handle items like this requires utilizing the right kind of machinery for the task.

There are 7 major lift truck classes, including power sources such as liquid propane gas, hydrogen fuel cell, electric, gasoline and diesel. The power source is linked to several of these specific classes. The main power sources for forklifts comprise Battery, Diesel, Gasoline, Fuel Cell and Propane.

Electric powered trucks are the most common, mostly Class III, III and class I forklifts. Internal combustion engines are more common in Classes V and IV. The most popular electric power source is the lead-acid battery. Out of internal combustion trucks, roughly more than 90 percent are powered by propane.

The most popular power source for lift trucks is battery. Battery fueled models make up around 60% of the new forklifts sold in the United States. Their benefits include: less maintenance requirements, quiet operation, the ability to be utilized inside and outdoors with no harmful emissions.