So much hype and hyperbole surround the use of gasoline for fuels. And ultimately there is a good reason, and the economics and physics dictate that if there was a simple better alternative it would be far more ubiquitous and not necessarily squelched by the evil oil companies. Here are some interesting statistics on the physics and energy of various materials touted as good fossil fuel alternatives.
First let’s look at the culprit, gasoline. Gasoline contains 10 Calories per gram. When compared with other everyday items gasoline contains more energy per gram. Some examples of other items where mentioned in previous blog posts, but this list is in addition:
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Item
|
Calorie Energy Per Gram
|
Flashlight battery
|
0.01
|
Lithium-ion battery (laptop type)
|
0.10
|
TNT (trinitrotoluene)
|
0.651
|
PETN
|
1
|
Butter
|
7
|
Gasoline
|
10
|
Methane (CH2)
|
13
|
Hydrogen (H2)
|
26
|
The high energy yield of gasoline is coupled with its useful properties. Gas when mixed properly with oxygen will cause a conflagration relatively efficiently and quickly releasing its energy for use. It is this energy, the process of mixing with oxygen, and sparking of an induced conflagration, that is the core process of an internal combustion engine. The high relative energy and ease of extraction make gas the logical choice to date for vehicles.
That said lets look at some of the statistics of other hyped alternative energy choices for motor vehicles.
Batteries
As can be seen in the chart above at the best batteries put out 1/100 the energy of gasoline. At this ratio considering that the average automobile contains about 100 lbs of gas or 15-17 gallons, it would take 5 tons or 10000lbs of expensive lithium-ion type batteries to equal the energy of gasoline. This is obviously not practical for the average automobile. That said, it has been tried..
Is the Tesla Roadster the answer? The Tesla incorporates 6831 relatively small lithium-ion batteries to create bursts of nearly 250 hp and 200 foot pounds of torque. This is on par with an average sedan like the Honda Accord. But it’s still impossible to escape the details of the energy use. It is true that the Tesla can run at bursts of 250hp and a top speed of 125 mph, but in order to pull these numbers it would be taxing the fuel cells at an unsustainable rate, likely depleting their available energy in under 15 minuets if ran at full speed. These numbers manifest that fact:
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Source
|
Available Energy
|
Weight
|
6831 Lithium-ion batteries
|
53kWh fully charged = 45,571 Calories
|
992 lbs
|
16 Gallons 87 Octane Gasoline
|
480,000 Calories (10 C/g)
|
100lbs
|
The Tesla Roster the darling of the electric car industry fully charged on new batteries that have not experienced any of the normal capacity lost expected over time has 10% the available energy in the average internal combustion engine. This does not even take into consideration the immense cost of replacing the batteries after an average life cycle of 5-7 years, and the environmental toll the disposal of lithium-ion batteries in-mass would ultimately have. Great strides are being made in the field of battery technology, but the chasm to equal the available energy in gasoline is still immense.
Hydrogen
One may have noticed in the chart above the incredible energy available in hydrogen, in-fact it has 2.6 times more energy per gram then gasoline. This coupled with the benign byproduct of only H2O-water, hydrogen seems an ideal alternative at first blush. These facts belie the truth though. The simple fact is hydrogen is at best a vehicle for stored energy, a type of battery, not a source of energy. Hydrogen is generally not available naturally in the environment (an interesting fact based on the atomic weight of Hydrogen that will be considered in later blog posts), it has to be manufactured. The process of manufacturing hydrogen takes energy. The plants that manufacture hydrogen would need to run on some other conventional source of energy such as gasoline or coal. Net-net the amount of energy you can get out of hydrogen is at best equal to the amount put in. So the burning of hydrogen although clean on the streets is not creating a truly eco-friendly alternative to gasoline.
Other Alternatives.
Hybrid type vehicles that utilize both batteries and conventional internal combustion engines are a viable alternative. They draw upon the immense energy stored on gasoline while balancing the improving technology of batteries. But this considered, they still propagate the Gasoline addition – just at a more docile rate.
One hundred mile per gallon cars in the near future maybe, but a cure for the gasoline addiction – not any time soon, there really are not any known substances that equal the energy output and advantageous properties of gasoline – not yet at least.
Next week: More fun facts on Energy
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When im not writing im running my Web development company here: http://onpagevisibility.com
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