Diesel-powered vehicles use diesel engines, which operate by compressing air to ignite fuel. This type of engine is known for its efficiency and durability, making it popular for heavy-duty applications like trucks and buses. Diesel fuel is denser than gasoline, providing more energy per gallon, which can lead to better fuel economy. These vehicles are commonly used in various industries, including transportation and construction. While they offer advantages such as increased torque and longer driving ranges, diesel-powered vehicles also produce higher levels of nitrogen oxides and particulate matter, raising environmental concerns compared to gasoline-powered options.