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

As diesel is not a pure gas, and it is not a pure diesel designed engine, it has some disadvantages in the department of fuel efficiency, as well as Methane slippage.. Like for instance, the fuel efficiency can be 5% to 8% less than in a comparable lean-burn, spark-ignited engine at 100 percent load. It could even be lower or higher loads.

Lift Truck Classification and Fuel Sources
There are certain recycling materials handling applications that can prove extremely challenging for lift trucks. For instance, scrap metal is one of these problems. In order to successfully handle things like this requires using the correct type of equipment for the job.

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

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

The battery is the forklifts most common power source. Battery fueled units make up approximately 60% of the new forklifts sold within the United States. Their benefits include: quiet operation, less maintenance requirements, the ability to be used outside and inside with no harmful emissions.