An electric vehicle can never capture more than 16% of the energy in the source.
The maximum efficiency for a natural gas turbine generator is 40%, and it goes down from there.
The maximum efficiency of a functional electric motor is 40%, and it goes down from there.
Forty percent times 40% equals 16% maximum, recoverable energy.
Recently, there are strange claims being made for higher efficiency for electric motors. Who knows what the rationalization is, since efficiency is a ratio. But there must always be at least 60% loss of energy in a functional electric motor for inviolable reasons, which are these:
Electrical energy must be concentrated as mush as possible in a motor. If it is spread out, the force drops, and more energy must be applied. Therefore, engineers always put so much amperage through such small wires in a motor that the resistive loss is around 30%. Inductive loss varies with conditions.
The net effect is that the highest efficiency achievable under laboratory conditions is said to be 60%. Under operating, commercial purposes, it's 40%. These facts have been inviolable for more than a century. Efficiencies do vary; but they vary from 20 to 40%, not 40 to 60%.
Electric motors are designed to be as hot as possible, if heavy work is the purpose. To make them colder would require more wire, larger motors and more energy. Optimum is the maximum amount of heat the motor will handle.
Compared To Other Autos
Considering a lot of other losses, an electric auto will convert 5-10% of the energy in natural gas into motion. A normal vehicle will convert 20-30% of the energy in gasoline into motion. That's 3 or 4 times more energy recovered with an internal combustion vehicle than an electric vehicle.
Electricity is a specialty product. It's not appropriate for transportation. It looks cheap at this time, but that's because it was designed for toasters, not transportation. Increase the amount of wiring and infrastructure by a factor of a thousand, and it's not cheap.
Electricity does not scale up properly to the transportation level due to its miniscule nature. Sure, a whole lot can be used for something, but at extraordinary expense and materials.
Using electricity as an energy source requires two energy transformation steps, while using petroleum requires only one. With electricity, the original energy, usually chemical energy, must be transformed into electrical energy; and then the electrical energy is transformed into the kinetic energy of motion. With an internal combustion engine, the only transformation step is the conversion of chemical energy to kinetic energy in the combustion chamber.
The difference matters, because there is a lot of energy lost every time it is transformed or used. Electrical energy is harder to handle and loses more in handling.
The use of electrical energy requires it to move into and out of the space medium (aether) through induction. Induction through the aether medium should be referred to as another form of energy, but physicists sandwich it into the category of electrical energy. Going into and out of the aether through induction loses a lot of energy.
Another problem with electricity is that it loses energy to heat production due to resistance in the wires. A short transmission line will have 20% loss built in, and a long line will have 50% loss built in. These losses are designed in, because reducing the loss by half would require twice as much metal in the wires. Wires have to be optimized for diameter and strength, which means doubling the metal would be doubling the number of transmission lines.
High voltage transformers can get 90% efficiency with expensive designs, but household level voltages get 50% efficiency. Electric motors can get up to 60% efficiency, but only at optimum rpms and load. For autos, they average 25% efficiency. Gasoline engines get 25% efficiency with old-style carburetors and 30% with fuel injection, though additional losses can occur.
Electricity appears to be easy to handle sending it through wires. But it is the small scale that makes it look cheap. Scaling it up takes a pound of metal for so many electron-miles. Twice as much distance means twice as much metal. Twice as many amps means twice as much metal. Converting the transportation system into an electrical based system would require scaling up the amount of metal and electrical infrastructure by factors of hundreds or thousands. Where are all those lines going to go? They destroy environments. Where is that much natural gas going to come from for the electrical generators? There is very little natural gas in existence when using it for a large scale purpose. Natural gas has to be used with solar and wind energy, because only it can be turned on and off easily for backup.
One of the overwhelming facts about electric transportation is the chicken and egg phenomenon. Supposedly, a lot of electric vehicles will create an incentive to create a lot of expensive infrastructure. There are a lot of reasons why none of the goals can be met for such an infrastructure. The basic problem is that electricity will never be appropriate for such demanding use as general transportation, which means there will never be enough chickens or eggs to balance the demand. It's like trying to improve a backpack to such an extent that it will replace a pickup truck. The limitations of muscle metabolism are like the limitations of electrical energy.
Electrons are not a space-saving form of energy. Electrons have to be surrounded by large amounts of metal. It means electric motors get heavy and large. When cruising around town, the problems are not so noticeable. But the challenges of ruggedness are met far easier with internal combustion engines. Engineers say it is nice to get rid of the drive train with electric vehicles. But in doing so, they add clutter elsewhere, which adds weight, takes up space and messes up the suspension system. Out on the highway, the suspension system is the most critical factor.
These problems will prevent electric vehicles from replacing petroleum vehicles for all but specialty purposes. The infrastructure needed for electric vehicles will never exist when limited to specialty purposes. This would be true even with the perfect battery which takes up no space and holds infinite charge.
Electricity is a very inefficient method of handling energy. Propagandists have been lying about it.
A Problem with Fake Numbers
Bureaucrats determine auto efficiency through numbers which they derive in strange ways. They have themselves convinced that electric vehicles (EVs) are five times more efficient than petroleum based vehicles (PVs). The real efficiency is similar for both, as explained above, when electrical loses are ignored, and about 5 or 10 times less efficient for EVs, when total infrastructure losses are considered.
To shoehorn their false assumptions into place, bureaucrats try to get PV efficiency down and EV efficiency up to show a ratio of 1/5. They put PVs somewhere around 15% efficiency, when they are 25-30% efficient, and EVs around 60% efficient, when they are around 25% efficient. Even that combination is a 1/4 ratio; but with a lot of vagaries and slop numbers, the difference is supposedly 5 to 1.
What makes bureaucrats assume EVs are 5 times more efficient than PVs? It's not entirely clear, but they do have an energy conversion problem. They calculate kilowatt hours per mile for EVs and compare it to miles per gallon for PVs. They seem to think there is a lot more energy in kilowatt hours than there actually is, or less energy in BTUs of petroleum than there actually is, or maybe both.
Part of their problem seems to be that electricity is cheap to deliver compared to petroleum, while not-so-bright persons assume cheapness is the same as efficiency. Electricity is only cheap with the previous electrical infrastructure designed for toasters, not autos, and with coal or gas as the source. When crude was $120 per barrel, idiots could have gotten a lot of false impressions on the efficiency of electrical energy. Now the numbers are changing, but the rationality is not improving.
There is not a correct relationship between kilowatt hours and petroleum BTUs due to a misdefinition of energy. Physicists cannot measure the actual relationship between kinetic energy and other forms of energy. They fake the results and contrive a floating value for the relationship between kinetic and other forms of energy.
Not the least problem is that physicists deal with the resulting errors by contriving. And they contrive, and contrive, and contrive. So all related facts become contrivances. Which means there is no way to pin down the real energy relationships.
But there is an analysis which is independent of those contrivances, and it is explained above. In that analysis EVs function at about the same efficiency as PVs in the auto, while 5 or 10 times that amount of energy is lost in getting electricity to the EVs.
All engineers, outside the bureaucrats, agree that PVs get 25% efficiency with old style carburetors and 30% with fuel injection, while other factors could lower it somewhat. The maximum efficiency for experimental electric motors is 60% under ideal laboratory conditions at one optimum speed and torque. EV motors are not so optimized, and average driving conditions take down efficiency, which should be 25%, but no one can say exactly. It's certainly not 40%, which might be maximum for EV motors at one ideal speed and torque. None of the uncertainties create much difference in efficiency for EVs and PVs inside the autos.
There are recently some extremely high efficiency numbers being used for electric motors. It doesn't mean there is a new magic for removing heat from metal and wires; it's nothing but a numbers gamelike efficiency in the absence of torque, while the energy disappears into heat the minute torque is added. One of the stunts is to misrepresent the relationship between electrical and kinetic energy. Due to the misdefinition of energy there is no real relationship between the electrical and kinetic energy numbers being used. Kinetic energy power is erroneously defined in terms of velocity, which shows high values for high rpms, which is characteristic for electric motors.
There is a loss within electric vehicles due to speed control. When the speed of an electric motor is controlled with dc voltage, there is a loss of about 40% in the control circuitry. Ac voltage control can be more efficient with "light dimmer" type of controls, but inverters which convert battery dc into ac lose about 30%. So it is quite likely that electric vehicles do not get 25% efficiency going from batteries to kinetic energy.
2. Comparing Energy Costs per Mile for Electric and Gasoline-Fueled Vehicles.
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