Brilliant Ways To Use Diesel MPG vs Gas
Diesel Engines far More Fuel Efficient than Gasoline Counterparts, but Why?
Diesel engines are considerably more efficient than gasoline engines. The miles per gallon of a diesel engine is 30 – 35 percent better than a comparable gasoline engine. The reason why compression engines are more efficient than spark engines is that diesel is a more efficient fuel than gasoline.
The difference between diesel mpg and the miles-per-gallon of a gasoline engine is a consequence of the power-potential of diesel. Diesel has a higher energy density than gasoline. Diesel is markedly more efficient than gasoline because diesel has a higher Btu.
The Btu of a Gallon of Diesel Versus a Gallon of Gasoline
The British thermal unit (Btu) is a unit of measurement. In the case of liquid fuels, Btu is the amount of energy output per unit of volume. There are two means of expressing Btu energy contents. The first is HHV, High (gross) Heating Value. The second is LHV, Lower (net) Heating Value.
“LHV is closest to the actual energy yield in most cases,” according to the U.S. Department of Agriculture. Gasoline has an LHV of 115,000 Btu per gallon. Diesel has an LHV of 128,700 Btu per gallon. While the LHV of diesel is only about 12% greater than that of gasoline, the consequence is exponentially greater fuel mileage per gallon.
Diesel engines get 30 – 35 percent greater m.p.g. than gasoline even though the power output is only 12 percent greater. The reason is, in addition to having a higher fuel density; diesel also has a greater compression ratio.
Compression Ratio and Thermal Efficiency
Not only does diesel yield a higher Btu per gallon, diesel also has a higher compression ratio. Compression ratio is a major component in fuel efficiency. The greater the compression ratio, the greater the thermal efficiency.
Compression ratio is the measure of a fuel’s steady-state volume versus its maximum compression volume. Diesel engines can work at a compression ratio of between 17 to 21: 1. That means diesel engine pistons can compress diesel fuel down to 20 percent of its steady-state volume.
Two things occur when an engine has a high compression ratio. First, it produces a great deal of power in the form of heat. The greater the amount of power produced by fuel combustion, the stronger the engines components must be to endure the pressure and heat. Hence, diesel engines are extremely durable.
Secondly, high compression ratios produce high thermal efficiency percentages. Efficiency, with respect to fuel, is the product of input versus output. Literally, efficiency is power output divided by power input. Thermal efficiency is a measure of how much power — in the form of heat — is lost.
The higher the compression of an engine, the more power (heat) is converted into work output. Gasoline engines have a compression ratio of between 8 to 12: 1. A car with a compression ratio of 9.2: 1 loses 46 percent of its heat (power) out the exhaust. A car with a compression ratio of 14:1 loses less. But still, 40% of the power generated by the engine escapes out the exhaust.
A diesel engine with a compression ratio of 21: 1 only loses 14% of its power out the exhaust.
Rentar Fuel Catalyst and Net Btu of Diesel Engine
The Rentar Fuel Catalyst is a pre-combustion fuel catalyst that increases the fuel efficiency of a diesel engine by between 3 and 8 percent on track and wheel equipment and over-the-road trucks. On stationary diesel-powered generators, the Rentar can increase fuel efficiency by up to 12 percent.
On boilers and furnaces that burn No. 4 distillate fuel oil, the Rentar can increase fuel efficiency by up to 30%.
The Rentar increases fuel efficiency by narrowing the gap between a diesel fuel’s HHV and LHV. The Rentar makes a diesel’s lower (net) heating value closer to its high (gross) heating value through hemogination.
By neutralizing the polarization in fuel molecules that produce fuel clusters, the Rentar produces a cleaner burning fuel. The cleaner a fuel burns, the higher its LHV Btu.
In other words, the Rentar makes diesel — which is already very fuel dense — richer.