Do School Buses Run On Diesel Or Gas?

hDiesel engines are found in almost all school buses, and for good reason. They last longer, produce more horsepower, tow bigger loads, and run more effectively and safely than gasoline engines.

Do school buses use gas or diesel?

The current yellow school bus, equipped with today’s diesel engine, is the best option for student transportation, and it will remain so as federal clean-air regulations tighten. Millions of youngsters will enjoy a safe, dependable, energy-efficient, and ecologically friendly ride back to school this autumn thanks to diesel-powered school buses.

As students return to their classrooms around the country, our focus shifts to ensuring that they get at school in the safest and most reliable mode possible: the familiar yellow school bus. Approximately 560,000 school buses are preparing to transport over 26 million public and private school kids to and from school and school-related events each day, covering over 6 billion miles annually. Because of their dependability, longevity, and safety, diesel engines power 95 percent of all school buses in the United States. Over half of these (54%) use the cleanest, near-zero-emission diesel engine technology available.

Despite their long distances driven, school buses are widely regarded as the safest vehicles on the road. New school buses are more high-tech than ever before, with advanced safety features such as warning systems and improved driver sight, as well as a new generation of clean diesel technology under the hood. These new buses use ultra-low sulfur diesel (ULSD) fuel and modern technology diesel engines to minimize particulate matter (PM) and hydrocarbon (HC) emissions to near zero. Furthermore, an increasing number of school districts are powering their buses with blends of high-quality biodiesel and renewable diesel, cutting emissions and reducing reliance on imported oil.

Lower Emissions

Diesel school bus engines today are far cleaner than those developed in 1988. Advances in diesel engine technology have practically eliminated the old smoke and smell that many of us associate with engines from the past. Particulate matter (PM) and hydrocarbon (HC) emissions from new school buses using clean ultra-low sulfur diesel (ULSD) fuel are equivalent to or lower than comparable natural gas buses.

Furthermore, every school bus on the road eliminates the equivalent of 36 cars. There are 36 fewer automobiles clogging the morning commute for every bus on the road, saving fuel and emissions. Our students and communities are cleaner and healthier as a result of school bus service.


Diesel-powered engines emit less carbon dioxide, which has been identified as a greenhouse gas that contributes to climate change, than gasoline or natural gas-fueled engines due to their higher fuel economy. While zero-emission options such as electric buses are on the horizon, and a few are already on the market, diesel-powered school buses are biobased diesel that can provide significant and immediate climate advantages.


For many years, diesel has provided the safest and most reliable power for transporting children to and from school on the vast majority of the country’s school buses.

Fuel Efficiency

For school buses, diesel is the most efficient and cost-effective fuel, delivering superior fuel efficiency than natural gas buses. It gives 25 to 30% more mileage than similar natural gas in buses, according to conservative estimates.

Do buses run on gas or diesel?

Now, California is prepared to take the lead once more, this time by requiring a conversion to so-called renewable energy sources “By 2040, all buses will be “zero-emission.”

The latest campaign by California’s strong Air Resources Board (CARB) has the potential to marginalize natural gas as a bus fuel in the same manner that diesel’s adoption did previously.

In response, the California Natural Gas Vehicle Coalition has proposed broadening the definition of “zero-emission vehicles” to include not only electric buses, but also ones fueled by “renewable natural gas” derived from cow manure or decomposing organic matter in landfills.

According to the coalition, whereas ordinary natural gas reduces greenhouse gas emissions by roughly 15 to 20% compared to diesel, renewable natural gas reduces emissions by nearly 90%.

“Tim Carmichael, president of the alliance, which includes T. Boone Pickens-backed Clean Energy Fuels Corp, utility Sempra Energy, and engine maker Westport Innovations Inc, among others, said, “That’s going to be a significant step forward over where we are now.”

The stakes are really high. In California, almost 60% of buses currently run on compressed natural gas, or CNG, compared to only 17% nationwide. With about a seventh of the country’s 67,000 transit buses operating on California’s roadways, the state is an important market for both bus manufacturers and fuel suppliers.

Why do buses run on diesel?

Diesel is the most common power source for public transportation, schools, and intercity bus services across the country due to its safety, reliability, and efficiency. Diesel engines and fuel, or diesel hybrid engines, powered 84 percent of transit buses in 2020.

Which fuel is best for buses?

Many of you have seen my colleagues’ efforts in response to this question for automobiles. We conducted a similar life cycle analysis for buses and discovered that battery electric buses emit fewer greenhouse gases than diesel and natural gas buses across the country.

What the map shows

On today’s grid, a diesel bus would need to travel at the same miles per gallon as a battery electric bus to have the same life cycle global warming emissions as a battery electric bus (really the 2016 grid, the most recent data available).

This means that a battery electric bus operating in North Carolina, for example, emits the same amount of greenhouse gases during its entire life cycle as a diesel bus getting nearly 15 miles per gallon! Given that a comparable diesel bus only gets 4.8 miles per gallon, this is quite excellent. So, in North Carolina, you can run three electric buses and emit the same amount of pollution as a single diesel bus.

Electric buses are better for the climate than diesel buses everywhere in the country

In terms of miles per gallon emissions-equivalency, battery electric buses are 1.4 to 7.7 times better than diesel buses. Another way to put it is that, depending on the region, a diesel bus emits about 11 1/2 to 8 times the global warming emissions as an electric bus.

Every year, the grid becomes cleaner. Electricity emissions have been continuously declining for the past sixteen years. Transit agencies can also pick cleaner power than what is offered on their grids by installing solar panels and batteries on-site or by contracting for renewable electricity.

When charged with the national power mix, a battery electric bus emits the same amount of greenhouse gases as a diesel bus that gets 12 miles per gallon. This is 2.5 times more efficient than a diesel bus (4.8 miles per gallon).

They’re also better than natural gas and diesel-hybrid buses

Battery electric buses have lower life cycle global warming emissions than natural gas and diesel-hybrid buses across the country. An electric bus emits 1,078 grams CO2e per mile when charged with the national power mix, whereas a natural gas bus emits 2,364 grams CO2e per mile and a diesel-hybrid emits 2,212 grams CO2e per mile.

(Note that the CO2e per mile figures are based on the same study as the miles per gallon emissions-equivalent values shown on the map, but in different units.)

Natural gas buses emit 12 percent fewer greenhouse gases than diesel buses. Electric buses emit between 29 and 87 percent fewer pollutants than diesel buses and 19 to 85 percent fewer pollutants than natural gas buses.

The table below shows the total life-cycle global warming emissions per mile from electric buses in all US regions.

Which two fuels are used in bus?

The letters (LPG) and (CNG) stand for liquefied petroleum gas and compressed natural gas, respectively (CNG). These two fuels are utilized as an alternative fuel to reduce vehicle-related air pollution. Other fuels, such as gasoline and diesel, which are used in cars and buses, pollute the air.

What kind of fuel is diesel?

The distillate fuel oil sold for use in motor vehicles that use the compression ignition engine named after its inventor, German engineer Rudolf Diesel, is known as diesel fuel. In 1892, he received a patent for his original design. Diesel fuel is made from a combination of crude oil and biomass resources.

Will buses run out of fuel?

‘The fuel problem has had no impact on London buses,’ a TfL official said. TfL said that there is no shortage of bus drivers and that it has a contingency plan in place in the event of future shortages.

What kind of gas do city buses use?

According to the APTA’s latest data, 41.3 percent of public transit buses in the United States used alternative fuels or hybrid technology as of January 1, 2014. This is in sharp contrast to the 2.1 percent of vehicles that used alternative fuels in 2013. According to the Energy Information Administration’s (EIA) Annual Outlook, the percentage for autos is 4.2 percent when flex-fuel vehicles are included.

According to APTA figures from 2014, 16.9% of public transit buses were hybrid-electric. Public transportation networks state that compressed natural gas (CNG), liquefied natural gas (LNG), and mixes were used by 16.7% of U.S. transit buses. 7.4 percent of public transportation buses run on biodiesel. Other alternative fuels like propane and hydrogen make up 0.3 percent of the total.

Where is the engine on a school bus?

“Flat-nose” and “dog-nose” are the two main body styles. The engine can also be labeled as “back engine (RE)” or “front engine (FR).” The engine of a dog-nose bus must be located in the front half (under the “dog-nose”). The engine is easy to access with this design because the dog-nose cover simply folds up. The disadvantage is the loudness; any bus with an engine up front makes a lot of noise while it runs. A front or rear engine can be used in a flat-nose. Because the engine is located at the back, RE buses are more quieter while driving. A rear engine, on the other hand, takes up some room in the back.

Front-Engine Vehicles

The engine is positioned in front of the vehicle, in front of the driver and the front axle line. The bus is made more spacious by placing the engine forward of the driver. In addition, most front-engine buses have spacious cabins to adequately seat people. Because the engine is not directly near to the cabin, interior noise levels are reduced. The motor in most FE vehicles is easily accessible for maintenance and repair.

There are some drawbacks to putting the engine in the front. Due to the weight transfer, it may limit the bus’s braking capability. Because there is no static weight, there may be a decline in accelerative ability. Even though it has a few drawbacks, the front-engine arrangement is the most prevalent.

Rear-Engine Vehicles

The engine is located in the rear of RE buses. The engine is essentially housed in the trunk. Furthermore, due to a large amount of weight from the engine resting on the rear tires while braking, rear-engine cars have great braking performance. As a result, instead of just the front tires, all four tires are engaged when braking. Acceleration is also improved since the engine weight and rearward weight transfer combine to exert maximum downward force on the rear tires, resulting in accelerative traction thanks to a rear tire contact patch.

Colorado West Equipment is the ideal bus dealer for all of your transportation needs, whether you need new fleet buses or a church transit bus.