It makes much more sense to put gasoline engines in the passenger vehicles which can burn this leftover gasoline, than to put diesel engines in the passenger vehicles which will then compete for the fixed quantity of diesel being produced.
Thus, neither engine type would be economically well suited for use in all vehicles, regardless of technical considerations. Whenever fuel for one engine type is created, fuel for the other engine type is created as a byproduct and someone will come along with an engine that can burn that byproduct.
Diesel engines are significantly more expensive, but have lifetimes many times greater than gasoline engines. For a commercial vehicle that is on the road all day every day, it adds up to big savings because of the better fuel efficiency and less downtime for repairs. Car companies claim that even if diesel powered consumer vehicles are superior to gasoline, consumers in the US won't buy them.
It's not worth debating the validity of that claim here, but it is worth noting that in other places such as Europe, a large percentage of consumer vehicles are diesel. So the answer may be more cultural than scientific whether I mean US consumer culture or Big Three car company culture is open for interpretation. Given two engines of similar weight, both operated at their respective optimum efficiency i.
But a Diesel engine will generally offer slightly more power out of this, by giving more torque; that's how it's more efficient. However, such optimum efficiency is always reached at pretty low RPM. Now, piston engines actually offer most power at high RPM, albeit at the cost of reduced efficiency. For trucks, this isn't economic though. Another consideration, in the United Kingdom at least, is that you can buy "red diesel" diesel fuel, dyed red for use in agricultural use, stationary generators etcetera with far less tax.
If a similar thing occurs in other countries this is no doubt one reason that diesel engines dominate these industries. You would not be able to make a petrol engine that would use sufficiently less fuel over its lifetime to recoup such a fuel cost differential.
I don't know but I would venture to suggest that such a situation arose years ago when petrol engines simply couldn't produce the required torque or reliability at the required conditions so diesel was the preferred option. Legislation on fuel tax for different uses will not keep up with modern rates of development by private companies. Granted, the red diesel argument doesn't cut it with road going vehicles, but when you consider the load pulled in a 40' trailer is comparable to that of a tractor and trailer in a field it is easier for engine manufacturers to make two similar engines tailored to the market.
I don't know anywhere near enough about who owns who when it comes to diesel engine manufacturers over the past fifty years but it is at least some food for doubt. Finally, if everyone used diesel, the police would have to check every vehicle for red diesel in the fuel tank, rather than the small percentage that could feasibly use it today.
This would costs governments and oil companies many millions in lost revenue, which would be unthinkable of course. Diesel engines - contrary to that claimed above - do have throttle plates; these regulate the incoming air flow - which in turn regulates torque, power, and revs. Diesel engines typically can run an extremely high compression much higher than typical gasoline engines due to the fuel they use that - amongst other things - doesn't compression-ignite at compression ratios that would in a typical gasoline engine.
And that - plus the ability to produce high torque figures both reliably and for the work done economically - is why Diesel engines are made. This is why we see modern day gasoline cars - especially the European ones - all coming out with direct injection; like most diesels have had for years. As this way the combustion process can be better controlled for all conditions and driving "modes".
Diesel engines - unlike most typical gasoline engines, especially those of a decade ago - almost always ensure that they fire precisely at top dead centre TDC due to the fact that they rely on compression-ignition.
Many typical gasoline engines - some of even today - are without the precision to fire every single combustion cycle right at TDC due to the complexity of an engine and how fast things inside move; and when this fails to happen efficiency and torque soon drop. Comparably, Diesel engines don't need electronic ignition systems at all, and they don't have high crankshaft speeds either an ocean liner diesel will rarely do more than - rpm, if that.
It is a fallacy that Diesel engines are way more efficient than typical modern day gasoline engines. These days - especially with non-leaded gasoline products that support high compression - typical gasoline engines are not only turbocharged, direct injected and running high compression ratios - but they're also capable of both, greater crankshaft rotational speed bandwidths than diesels and also producing big torque numbers at low crankshaft rotational speeds, too.
That hits the same target as several of the unique selling propositions that diesels previously offered. Particularly in industries involving transport, diesel is a widely used fuel. Additionally, diesel fuel powers construction and farm equipment, as well as some buses and ambulances.
Two-stroke, slow speed diesel engines propel some of the most powerful and largest engines throughout the planet. But why? Take a look at the amount of time that most trucks are used for. People get the most that they can out of these vehicles. They are used for long periods of time, and used hard. Sadly, this is a hotly debated topic among certain environmentalists. But facts are facts. Diesel engines in trucks, trains, boats, and barges help transport nearly all products people consume. Diesel fuel is commonly used in public buses and school buses.
Diesel fuel powers most of the farm and construction equipment in the United States. The construction industry also depends on the power diesel fuel provides. Diesel engines can do demanding construction work, such as lifting steel beams, digging foundations and trenches, drilling wells, paving roads, and moving soil safely and efficiently.
The U. Diesel engines are also less likely to stall than gasoline-fueled engines. Diesel fuel is also used in diesel engine generators to generate electricity. Many industrial facilities, large buildings, institutional facilities, hospitals, and electric utilities have diesel generators for backup and emergency power supply.
Most remote villages in Alaska use diesel generators as the primary source of electricity. Source: Alaska Center for Energy and Power. Diesel fuel explained Use of diesel. What is energy? Units and calculators. Use of energy. Generators are well known to use diesel as a fuel, especially in those situations such as emergencies where a generator is required to be used for extended periods of time. Diesel Engines can also be found in construction equipment, especially the ones where the machinery has perform a lot of heavy lifting to get the job done.
Concerning other transport, trains had used diesel engines in the past, before the trains began to be switched to more environmentally friendly methods of fuel such as electricity and bio fuels. Also, trains have been using some magnetic levitation to increase efficiency instead of using diesel. As we have seen, it is always the equipment that does the heavy lifting and is required to be used for long periods of time, such as the diesel generator.
So why do heavy trucks, such as the semi-trucks, use diesel as their fuel of choice? Considering that trucks are required to be used for long periods of time, they could go for gas powered trucks which are environmentally friendly. Especially for semi-trucks, which are required to carry heavy loads and have an obligation to be on the road for a high number of hours. Now that a basic understanding of diesel engines, we must now move onto the reasons why semi-trucks use diesel.
Here they are:. If you look at the energy produced by diesel, you will see that diesel produces about , BTU of energy. Compare that to gas, which produces around , BTU of energy. What this means is that for every drop of fuel used, diesel produces more energy than gas overall.
It is advantageous for semi-trucks to use diesel when carrying heavy loads. The semi-truck can accomplish more mileage with diesel as a fuel than gas simply because diesel produces more energy than gas. What this means is that the semi-truck does not require as much diesel as it would require for gas to carry the same heavy load from point a to point b. This has a significant impact on the efficiency of the diesel engine. In terms of operating time, diesel engines can run for longer than gas engines before requiring maintenance.
This is simply because of the diesel engine not requiring spark plugs, which need to be regularly replaced in gas engines. It is estimated, for example, that diesel engines can operate for to hours before requiring maintenance; gas powered engines can run for hours before requiring maintenance.
What this shows is that the efficiency of the diesel engine is better overall to the point that the diesel engine can run for longer than a gas engine.
Therefore, the semi-truck can use diesel to travel distances for more extended periods of time and also with using diesel fuel in a diesel engine, less maintenance is required than a gas powered engine. In terms of the cost, using diesel fuel to power semi-trucks significantly reduces the costs for this type of truck and among other heavy vehicles.
The costs of using diesel are linked to the efficiency of the diesel as a fuel and also the fact that the engine that diesel is used in has low maintenance requirements. It should also be noted that fuel costs per kilowatt are thirty to fifty percent cheaper than with gas.
Take the cost of fuel, for example. Since diesel produces more energy than gas, that means that diesel as a fuel can accomplish more mileage than gas overall. That means that for the Semi-Trucks, this means that the truck driver does not need to refuel regularly with diesel. As we also stated in the section about how the diesel engine worked, the diesel engine does not require spark plugs to initiate combustion in the engine.
Since spark plugs need to be regularly replaced in gas engines, this means that the maintenance costs in the gas engines are more expensive than diesel engines. Whereas in diesel engines, it is the injection of diesel fuel, at high pressure, into the combustion cylinders to heat up the engine before beginning the combustion process makes diesel engines cheaper.
So what this means is that the Semi-trucks do not have to be maintained as much with diesel engines rather than with gas. The costs overall are lower and therefore for the businesses who use these Semi-trucks, they do not have to spend as much with their budget on the cost of maintenance of these trucks.
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