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Electric Cars illu

Will it come before Christmas ?

ShifTech engineer's opinion :

As an engineer working on combustion engines optimizations and mapping I always wondered whether electric cars could ever seduce me.I used to discuss the topic at home with my family, but we were rather mocking the electric cars subject. An uncle of mine, auto sport fan, was actually teasing me when I was young stating “It is such a pity, when you get your driving license, combustion engine motorized cars will no longer exist, you won’t ever get the chance to drive a fuel combustion engine powered car.

Obsessed by the idea I might have no other chance but to drive electric car I became quite a strong supporter of combustion engines. Countdown had started so I tried to follow a maximum number of rally’s where I would only listen to Porsches and BMW equipped with their typical six cylinders engines. At that time cars were much louder drivers were insane and supporters were getting unconsciously close to the tracks. Nurtured in autosport environment since early age I would never have imagined one day cars could be hybrid or full electric. And I actually got quite reassured when I saw first hybrid models. Remember Toyota Prius and Honda Insight Hybrid … Combustion engines still had bright future ahead!

Then came the Tesla. Not talking about the first model as a race track dedicated electric car would never convince me. No I am talking about the second model, the one looking like a real car … eventually. That model made me realize “why not?” Now come a series of questions; would driving an electric car make me a better human being? More responsible? Or would it simply change nothing at all?

Answering this question was not that simple. Having quite a rational mindset I would need more than a single “Fuel-free driving is good”. Here is why I needed to understand and integer series of parameters in order to grasp global carbon print of electric versus combustion engines cars. A recently published article about Tesla S model being taxed in Singapore because of its CO2 emissions rate made me dig a little deeper.

To build an objective opinion I based my research on few recent articles in order to globally compare combustion and electric engines. Febiac has published figures that demonstrate Co2 emission per car in 2015 in Belgium was about 120gr/km (118.9 precisely). Tesla S model consumes about 181Wh/km (Tesla figures). The aim is therefore to measure how much CO2 does the production of electric power release in order to estimate how much a Tesla S model would pollute. According to Electrabel 2014 figures producing one Kwh would release 181g CO2. This includes nuclear power plants, TGV power plants, wind power plants, etc. For the record our French neighbors got this number down to 79gr CO2 per one Kwh whilst our Chinese friends are probably amongst the worst as they release 766gr CO2 per one Kwh. France’s good results come from the fact that 80% energy is produced by nuclear power plants. Nuclear power actually gest maximum return (about 30%) whilst releasing less CO2. Bottom of the class remains coal massively utilized by countries such as China and Japan. 

Tesla’s carbon print will therefore vary depending on countries. Getting back to the Belgian example: a Tesla car will release 32gr CO2 per km. In comparison, a modern vehicle such as the BMW F30 320d efficient dynamics releases 99gr CO2 according to NEDC cycles. One might say NEDC cycles do not mean much when we know what the car really consumes but be aware that Tesla is not the less one cheating on electric consumption figures. Sources indicates 33% increase compared to what was announced by the manufacturer; and it is not that far away from what can be observed through actual NEDC cycles.

Gap looks quite significant between the Tesla and the BMW BMW, but should we stop here?

Not at all. For the sake of completeness we must consider how much energy is needed to extract fossil resources (petrol/diesel) and transport it to gas stations as electric power to the supercharger would. Based on ADEME sources 15% additional CO2 per km must be considered for the transport bringing our F30 320d example up to 114gr CO2/km. However as shown by an American institute there is a waste of energy estimated to 6% between recharging terminal and the electric vehicle. 15% CO2 can be added due to lithium batteries production. This brings our Tesla up to 39gr/km. And that’s not all. Tesla’s weakness is the energy waste at rest ; The car is never entirely off but rather on standby. Which enables Tesla to perform updates or detect anomalies when the car is stationed. Those wastes are estimated to 5.1kwh daily. 5.1kwh being equivalent to about 200gr CO2 daily and knowing average Belgian drivers travel about 40km daily (Statbel source) this adds 23gr/km CO2 to our Tesla. Which brings emissions up to 62gr/km.

This analysis looks quite precise but could get more detailed should it consider production energetic costs. This would include: raw material extraction, production appliances electric energy, lithium extraction, etc.

According to The Guardian, CO2 production for a car equivalent to our BWM 320d is about 17 tons. Such number has to be put on perspective with the distance traveled by the vehicle to get it converted into kilometers. This last factor was not published officially. But life cycle of an average vehicle is generally estimated to 200 000km. This gets our estimation to 85gr CO2 per km, astonishing! The number is around 16tons regarding the Tesla converted into 80gr CO2 per km. We could even dig this subject deeper by measuring carbon print from batteries recycling (information not available); however I do think this analysis is detailed enough to get you an idea on the real carbon print difference between those two vehicles.

Adding all those figures gets the CO2 emission amount up to 191gr/km for the BMW versus 142 gr/km for our Tesla S model. We could actually mention maintenance costs being much lower for the Tesla but counterbalanced by the memory effect of the lithium batteries that eventually have to be replaced (although benefiting from 8 years warranty). 



Those numbers might convince you to acquire an electric car; whatever we say electric energy is the future. Unfortunately electric vehicles still depend on energy used for electric power production as well. Although results of the above comparison give advantage to the Tesla the outcome would be completely different should this study be realized in USA or China.

It is anyway much easier to turn TGV or coal power plants into renewable energy power plants than change people’s minds and renew the entire fleet. Even if everyone was acquiring a Tesla tomorrow (and impact on CO2 emission would remain pretty much unchanged) CO2 emissions could actually be much lowered if the energy providers turn green. That’s what is actually supposed happen should legislators want to meet the 2° global warming limit set by the COP21.

Let’s hop Belgian authorities do not find a way to tax electric vehicles based on their real carbon print just as Singapore did. And this would be quite a big step backwards as it would mean that individuals having made the electric choice should have to pay for non-green electric power providers. In this situation we can wonder whether drivers reloading batteries from their own solar panels be considered as well … Although it is quite early to talk taxes be aware electric vehicles sales will take off as soon as authorities will manage to benefit from it as they did from combustion engines vehicles.