Unless you are planning on bringing an alien tech from another world or dimension and handing it over to Elon Musk the founder of Tesla, we are very far from seeing a self rechargeable electric car.
Why can’t an electric car charge itself? An electric car can’t charge itself because it defies BASIC LAW OF NATURE, which says, energy can not be created.
And I am going to walk you through why an electric car can not charge itself.
What is an Electric car?
Firstly, let us unravel the first part of the puzzle, let’s get a good understanding of what an electric car is. An electric car should not be confused with hybrid vehicles.
An electric car according to Wikipedia is a vehicle that is powered by electric motors (induction motors), using energy stored in large batteries, electric vehicles or EV as they are popularly called have been around since 1800 but became quite popular in the 20th century.
The electric vehicle was made possible by the invention of Nikola tesla, the induction motor revolutionized the automobile industry. It works on the principle of a rotating magnetic field causing the induction motor to rotate when electricity is induced in the rotor.
An induction motor works better than an internal combustion engine owing to its many application in the industry due to the following pros:
- An induction motor has no permanent magnet
- It has no brushes
- It has less moving parts than an internal combustion engine
- Creates higher RPM and torque than an internal combustion engine (ICE)
Furthermore, the wheels of an electric car operate through the movement of an induction motor, while the induction motor is powered by a large pack of batteries stored under the vehicle. The electric vehicle is quite different from the hybrid vehicle due to the fact that it does not require fossil fuel bringing us back to our main question “ why electric cars can not charge itself”, one of the reason is already mentioned above, which is an electric car does not use an internal combustion engine.
Internal Combustion Engine
An internal combustion engine is found in the majority of car engine operated today, the engine is called internal because the air gasoline mixture takes place internally inside a cylinder, when the ignition of a car is turned on, it fires the spark plug through the electricity stored in the car battery.
Then the ignited spark plug causes an explosion in the cylinder which results in the mechanical motion of the piston creating the movement of the car, the alternator is hooked to the internal combustion engine, when the engine is running the alternator charges the battery ordering the smooth movement of internal combustion cars.
This works very differently from an electric vehicle, remember an electric vehicle does not have an alternator that will charge the battery of an electric vehicle because it does not use an internal combustion engine rather an induction motor and a set of rechargeable batteries although some might argue that “what if an alternator was fit inside of the electric vehicle to recharge the batteries “? But this will also be an inefficient setup and here is why.
The inefficiency of an alternator/generator set up
Most people with this school of thought are thinking of recharging the battery of an electric vehicle through an alternator which is driven by the electric motor when the car is in motion, if this system is possible, well if wishes were horses then humans would have altered the course of technology, and the close description to this kind of perfect system will be a perpetual motion system which in reality does not exist as this violates the basic rule of thermodynamics, you can not create energy out of anything.
Lets pause for a second and assume this is possible, that we can set up a battery, electric motor and alternator system to keep on working continuously.
We still have to deal with friction from the moving mechanical parts of the alternator and electric motor, all these losses from both sides will make the system inefficient because the energy is coming from the battery and is converted to mechanical energy in the spinning of the wheel and then to electrical energy which is used to recharge the battery, all these stages are inefficient in the conversion of energy from one form to another.
Another suggestion is why don’t we ditch alternator and power the electric car with a solar panel?
Do you think it’s a brilliant idea?
Well let’s find out below
Solar-powered electric cars
There have been so many whispers in the auto industry world about a self-charging electric vehicle, the closest we have seen to any of these grapevine talks is by a company called lightyear, they have carved out a niche for themselves when it comes to using suns power to power vehicle.
They won the WSC race for 3 years, now the team has a plan to deliver an electric vehicle called lightyear one covered in solar panel by 2021, though as of now many details about this is sketchy, we do not know the percentage of the car body surface that is covered with solar panel, or how they intend to achieve this feat.
Though some of the details about the performance of the car will make you wonder whether it is just an electric vehicle or a solar-powered EV, the company claims it new car the lightyear can go 450miles (725km) off of a single charge from its battery and also get 12km worth of charge in an hour from the car solar panel.
Coming to the fact that customers will now need to be parking under the sun to achieve this feat, but the lightyear one is really a 725km EV as compared to the 12km obtained from solar, the lightyear one is more like a conventional electric car than a solar-powered vehicle when you do the maths
The efficiency of solar panel
A solar panel produces the most inefficient form of electricity this is due to some factors such as cloud cover, relative humidity, sun intensity, material, reflection, and the Shockley–Queisser limit which are difficult to control.
Even the best solar panel produced by Sunpower is 22.8% efficient which is far lower than expected, making electricity generation through solar very inefficient as most of the radiation from the sun is a loss.
Therefore hooking up a solar panel to a car as a means of providing a self-charging car is not only inefficient when converting solar radiation to electricity but will also make the car heavier.
No doubt experts like Elon musk said in 2017 that “The least efficient place to put solar is on the car,” and Jeremy Michalek, a professor of mechanical engineering at Carnegie Mellon University said the maths does not add up when you try to put a solar panel on a car.
Unless there is a revolutionary breakthrough in the solar panel technology we will be seeing less of it in the auto industry.
In conclusion, although the auto industry is still growing with new innovation coming up every day, I will not hold my breath because we may see a self-charging car in the future.
Research carried out in Standford University California, suggests a new way of achieving self-sustaining electric vehicles through wireless power transmission.
This works on the idea of transmitting power wirelessly to a moving object called the receiver which in this case can be an electric vehicle although the major drawback of this method is the amount of electricity that can be transferred is very small, ranging in milliamps, which is too little to be of use, but all hope is not lost, currently electric vehicles already have regenerative braking that captures the energy dissipated and convert it to electricity when a driver steps on the brake.
This I believe is a step in the right direction in achieving a self-charging EV