Wednesday, June 19, 2019

Switching from ICEs to Electric - Goodbye´s and Hello´s


“You say goodbye and I say hello…”

I still remember the famous Beatles song “Hello, Goodbye”, which was used in kinder-garden to teach basic English to my kids and subsequently heard to exhaustion during car trips.  Now it becomes relevant again when I think about the changes that our beloved cars will put us through.

The car of the future will have an electric engine

After more than 100 years of uninterrupted service to our mobility needs, we are reaching the end of the Internal Combustion Engine (ICE) as means of propulsion in most of our vehicles.  The cars of our (very) near future will replace the ICE with an electric one (EVs).  We will say goodbye to ICEs and hello to electric while we ride and sing in our cars, like we have been doing for the past century.

The electric engine is better suited to our mobility needs

More than a 100 years ago, when engine powered carts were beginning to replace horse led ones, the electric engines were competing with the rudimentary internal combustion ones in the race to leave the horses behind.  The reason that we got to enjoy ICEs in the end was not due to the nature of the engine itself, but to the means of storing the energy needed to run it.  Gasoline, at the time, provided much more energy density storage per weight and volume unit than batteries that stored electricity.  And we know how history unfolded.  We created a vast distribution network of fuel and we perfected the ICE incredibly during the past century, so that we could enjoy vast levels of personal mobility.

Pictured: Jay Leno driving one of his old electric vehicles, a 1909 Baker Electric, which can travel 100 miles on a single charge

We have come to appreciate the freedom that the car has provided to all of us.  And we have learned to live with the peculiarities of the ICE.  Its noise, vibration, emissions, extensive cooling needs, inefficient power delivery.  Engineers have made wonders perfecting those engines and either correcting those flaws (power delivery in modern turbo´s is much more linear…), controlling them (catalysts and other emission suppression elements) or masking them (insulation). 

But the truth is that burning fuel to provide movement is still extremely inefficient.  More than 65% of the energy burnt is lost in heat.  And turning a linear movement (the one that the piston produces up and down the cylinder) into a circular one (the one needed to turn the wheels) just complicates the task even further.

In the meantime, the side effects of our dense car park have become very apparent.  Pollution and noise in the cities, together with a need to slow down global warning, have led to clear indications that the ICE car is no longer a star.  Many cities in Europe (Athens, Copenhagen, Oslo, Paris) and even countries (France, Ireland, Netherlands, Norway, UK) are putting clear deadlines to the use of cars burning fuel in our roads.

The only alternative left then is to go back to our beloved electric driven cars (EVs) that originally lost the mobility race.  They are the only existing means of producing movement that does not emit any particles or CO2 when running on the road[1], while still providing a very similar mobility service.

Hydrogen driven fuel cells or batteries will feed the electricity to our EVs



At the same time, feeding energy to power an electric vehicle is becoming much more feasible in terms of cost, weight and volume needed.  Two potential avenues are currently being explored by manufacturers to store the electricity needed to run an EV. 

The first one, like a century ago, is to put a battery in the car that stores electricity and is recharged by plugging it into the existing distribution network.  Partly fueled by the mobile phone boom of the 21st century, battery technology has evolved enormously and, now that manufacturers are pouring money into them, will no doubt continue that trend.  Current battery powered EVs can store enough energy to move them for 400+ kilometers at a cost that is beginning to be economically competitive with ICEs. 

The second potential means of feeding electricity to an EV is using hydrogen as fuel.  A machine known as fuel cell will then transform the hydrogen into electricity that will feed the electric engine. There are no unwanted emissions in that chemical process, just plain water.

I believe the race is currently going at full speed between those two technologies and I will continue learning as much as I can about them until I finally dare to write an article about both.  However, there seems to be full consensus in the fact that the car of the future will be driven by an electric engine.

In the meantime, we are seeing a transition period, in which both technologies (internal combustion and electric) are put to work together (hybrid vehicles) trying to combine the virtues of ICEs and electric.  But there will be a gradual transition to electric only vehicles, many of which are already offered to all of us.

Switching from ICE to electric, what can we expect?



As mentioned earlier, in a plain comparison between an internal combustion engine and an electric one, we see that the latter is naturally much better suited to our mobility needs[2].  It is smaller for a given power delivery.  It is much more efficient.  It is quieter. And it generates the type of circular movement that wheels require.  That is the rosy picture that anyone who has driven an electric powered car, or a hybrid in electric only mode, has experienced.

In any transition to a new technology, however, there are many habits that can be left behind (our goodbyes) and other that need to be acquired (the hellos).   I will briefly try to summarise what to expect when you make the switch from a traditional car driven by an internal combustion engine to one that has just an electrical engine.

Many goodbyes, some of them sad…

Goodbye to noise

The first thing anyone notices when driving an EV is the silence.  It is almost magical.  And it is not just the silence, it is the absence of vibrations that we were used to in the ICE that makes the experience so positive.

The internal combustion engine burns fuel in a combustion chamber, generating lots of noise and vibration in the process.  You may not be familiar with it, but manufacturers use an acronym called NVH (Noise Vibration and Harshness) in order to measure and control those effects of an ICE.  The less NVH a car produces, the more refinement that the driver will feel riding in it.

It is not a full goodbye to NVH with EVs, but the biggest sources of it are gone with an electric engine, producing an incredible relaxed sensation when driving them, compared to our good old ICEs. 

At higher speeds, wind and tyres still produce significant roar, but in the city the difference in noise between an ICE car and an EV is amazing.

Not only the people driving in the car enjoy the decrease in noise.  For pedestrians the benefit of silence is just appalling[3].  Try to imagine a city in which all vehicles (cars, bikes, mopeds, buses, trucks...) are electric and you will realise how much better quality of life we will have in the cities of the future.


Goodbye to (manual) gearboxes


It used to be almost a cultural difference.  Americans drive automatics, Europeans drive manuals.  Still, the majority of cars sold in Europe have manual transmissions.  The reasons why were the source of endless discussions in a pub.  Not anymore.

Say goodbye to manual transmissions in EVs!  One of the characteristics of an electrical engine is its almost linear power delivery.  Specially from rest.  For ICEs, the power delivery is very poor at low revs and growing with engine speed, including only a small optimum rev range in which the engine delivers power most efficiently[4].  Thus the need for a transmission with different gears that allowed to adapt the car speed and acceleration demands to the engine power delivery. 

A pure electric driven vehicle does not have a gearbox.  It transmits power directly from the engine to the wheels.  Don´t worry, you will not need to do any significant adaptation.  Just like in an automatic, you will have to choose between forward (D), and backward (R) movement or tell the car that you are parked (P).  No more clutch, no more gear selection, no more race to see which car has more gears (I am currently counting 10 as the current record for ICEs[5])

Goodbye to engine monitoring

Remember those wonderful dashes, full of needles that allowed us to monitor the proper running condition of our ICEs[6]?  Say goodbye to them. They are a thing of the past with electric engines.

An ICE is quite a complex machine, which needs a certain running temperature, a lubrification and a control of engine speed.  A rev counter is important to adapt the engine movement to your speed and acceleration demands[7].  The water cooling the engine needs to be kept below boiling point (temperature needle).  There needs to be enough oil to provide proper lubrication/cooling (oil temperature needle).  And the oil needs to flow properly around the engine block (oil pressure needle).  Other components also need monitoring, like the battery status, to provide enough charge to help start up the vehicle (battery voltage needle). 

In an EV you will be most concerned with the battery charge level and predicted autonomy.  That´s all.  No more.

Goodbye to risk of suffocation

I still remember some years ago, trapped in a traffic jam in a huge underground parking hearing a message through the speaker system “please turn off your engines, CO2 is reaching damaging levels for everyone´s health”.  In single home garages we are keenly aware of the danger that a running combustion engine and lack of ventilation pose to our health.  Say goodbye to that worry with EVs.  No emissions, period.

Just plug overnight and drive in the morning.  Tesla´s don´t even have an on/off switch.  As you open them, they are ready to drive.  An additional plus of their lack of emissions and with the side benefit of managing that precious stored electricity, most EVs offer the possibility of setting up a predefined interior temperature in the car by a certain time every morning when it is still plugged to the mains.  Given the efficiency of electric engines, they do not generate enough heat to be used in the car heater.  An electric mechanism is needed to do so and does not generate emissions when working either.

Goodbye to gas stations

Yes, battery electric cars need recharging and it takes much longer than the time needed to refuel a car.  Which means that most times they will be recharged at home or in a place where a long stop to do something else is taking place[8].

In both cases, replenishing your vehicle with energy will probably not be done in a gas station[9].  It is one of the tangible benefits mentioned by drivers of EVs compared to ICEs.  It seems that forgetting about that periodic stop at a gas station is much appreciated.  Say goodbye to gas stations in your battery electric vehicle.

Goodbye to complex engine specifications

We have gotten gradually used to them, but in their continuous engineering improvement of the inefficient ICE, most manufacturers have advertised technical details as a means of differentiating their products.  And we have learned about many of them.  Number of cylinders is still my preferred one, because it can really be felt in the noise generated by the engine whilst running[10]. 

Displacement has always been an indicator of the size of the engine and its expected power offer.  Be it cubic centimeters or cubic inches.  Many drivers know the capacity of their engines, because manufactures were keen to advertise them.  1.5 liters, 3 liters, 366 cubic inches.  Did we really understand that it was a measure of the amount of air plus fuel that would fit into the cylinders of the car and therefore bigger meant more powerful explosions inside the cylinders and a stronger power delivery?  Or we were just under the spell of the “bigger is better”?  In any case, with the efficiency chase and the use of electronics, downsizing of engine capacity is the general trend in the ICE landscape for the 21st century.

But in their car badges is where we have learned best about the evolution of ICE technology.  In the 70s we learned that a turbo boosted performance[11]. Although forced induction had been tried many times in the past, it only became reliable and efficient at that time.  Now it has become the norm that allows for a more efficient engine and a better control of emissions, so most ICE cars of today use a turbo and it is not a differentiating characteristic anymore.

What about number of valves (16 valves, 4 valves per cylinder)?.  It was another way to improve the engine´s “breathing” that we learned about as important power enhancement without really knowing what more valves meant.  But they were a key development that manufacturers shared with us.

And so, in the past decades we learned much about technical specs that we did not fully understand such as direct injection, common rail, overhead cams, variable valve timing (Honda was especially popular with their VTEC badges), double clutch transmissions (made popular by the VW Group with their DSG badges) and the list could go on and on.

Electric engines are much simpler and so far their manufacturers just share with us their power and torque output, that is about it.  And they don´t yet make it explicit in their badges, just in the documented technical specs.  It makes sense, switching to an EV is differentiating enough and, although quickly growing, there are not too many of them on the market today, so they are unique enough to be marketed without a myriad of technical jargons.

Say hello to re-charging variations


Not every element of our transition to EVs is a simplification meant to make our lives easier.  We are at the early adoption stages of a new fundamental technology, so we will witness quick improvements in some technical aspects of the car.  The element that is showing quickest pace of change is the battery.  It is, after all, the most expensive component by far of an EV and the one that will be subject to the biggest part of the R&D budget.  Which means that we will see continuous improvements in their price, capacity per given weight/volume and charging speed.
A bigger capacity battery provides a much welcome increase in range, but it also requires longer charging times compared to an equally specified smaller one.

Charging time, on the other hand, is one of the main drawbacks of EVs compared to our reference of more than a century re-fueling ICE cars.  Suppliers and manufacturers have been working hard at improving that weakness.

Without trying to be technical, the charging speed of a battery depends on the maximum output of the outlet on which it is plugged, the maximum capacity of the on-board converter installed in the car, the maximum input capacity of the batteries, their level of charge, and their temperature.  I hope I am not forgetting any significant element of the recharging chain, this is how much I have been able to gather in all my research and readings.

The good news is that the many combinations can be ignored by the user, as they will just add up to a certain charging speed (kind of a minimum common denominator speed of all the elements involved).  More technically oriented users, however, will have “fun” trying to optimise every element of the charging chain.

The landscape of recharging is evolving so rapidly that time needed to replenish electricity will soon become less relevant.  The latest version of Tesla´s proprietary “superchargers” has a maximum charging rate of 250kW, which means adding up to 75 miles of range in 5 minutes[12]. 

Say hello to energy recovery

Remember that more than 65% of the energy used by an ICE is wasted in heat.  What a contrast then to know that in an EV you can actually recover some of the energy generated to move the vehicle.

All EVs include generative braking in order to recover some of the kinetic energy that is usually just transformed into heat via the brakes[13].  It is a relatively simple mechanism that recovers part of the energy that would be wasted as heat back into electricity that is stored in the batteries.  It does not replace the traditional brakes, it just complements them.

For the launch of their first EV, the e-tron, Audi invited journalists to one of the highest mountain roads in the US, Pikes Peak in Colorado, where the tarmac reaches the peak at 14.100 feet (4.302 mts).  The test consisted on riding the car 19 miles downhill and checking how much energy had been recovered.  It turns out that it was enough to cover about the same 19 miles distance on a flat road.  Impressive.

It can become quite amusing to see that your battery level is increasing when you are riding your car down a mountain road.  And regenerative braking is one of the reasons EVs are more efficient in city driving, where many starts and stops take place. 

Say hello to range anxiety

This anxiety is generated by three factors.  First, the relatively limited maximum range of the first EVs launched some years ago.  Second, the low density of recharging outlets available. And third, the long recharging times.  These restrictions limited the real usage of EVs to daily commutes and city driving. 

The landscape, however, is quickly changing.  Most new EVs show ranges around 300/400 kmts[14], which would allow for typical two hours driving on the highway comfortably at legal speeds.  The recharging network is evolving positively as well, although at different paces depending on each country.  And recharging times are quickly dropping as well.

In any case, we are far away from the current situation we are used to with ICEs., for which we can usually find a petrol station within 30 kmts when driving on highways and with typical 5 minutes replenishing time.  Hello then to range anxiety for a while.

Say hello to instant power

This is one characteristic of EVs that never fails to impress.  In the first few meters of movement, the acceleration is much stronger than with an ICE.

One of the advantages of electric engines is their almost linear power delivery, which means that they can provide full torque from start.  Remember, that is the reason why they do not need a gearbox.  And it is most obvious when starting movement.  Say hello to instant power.



Goodbye to liters and hp, hello to kW/h and kW

The power delivered by electric engines is usually measured in kW (kilowatts).  For ICE engines we were used to hp (horsepower), but manufacturers were slowly making the transition to kWs[15], so that measure of power deliver can be easily compared between ICEs and EVs.

We will have to learn differently when it comes to measuring energy input into and consumed by the car while running.  We used to measure the capacity of a fuel tank and pay for the energy replenished in liters or gallons.  And, consequently, define consumption in liters per kmts or miles per gallon.

With electricity, the unit of measure for energy purchased and stored by the batteries is kW/h (kilowatt-hour).  Just look at the bill from your utility company and see that they are charging you for the number of kW/h you have consumed[16].  Most electric appliances have a watt consumption rating.  And their time usage will determine how much energy is consumed.  For example, an electric heater consuming 1000 watts (1kilowatt) operating for one hour will use 1kW/h of energy.

Your EV car battery will have a maximum energy storage capacity measured in kW/h.  Typically, something between 40 and 100. 

What is more relevant to a driver is how efficiently the car is using that energy while running.  The favored measure will be kW/h per 100 kmts or W/h per kmt or mile. 

And the other important measurement is obviously how much distance will the car be able to cover with the available energy at the current rate of usage.  Which will be measured in kmts or miles.

Say hello to kW as a unit of power and kW/h as a unit of energy and their relation to all relevant measurements of consumption and costs when using an EV.

Try it out, say hello and sing along

These are very exciting times for anyone interested in cars.  Our favourite mode of transportation is undergoing amazing changes that will significantly affect our driving experience.

If you have not done so yet, I urge you to try it out for yourself.  There are many alternatives that allow you to drive an electric car for some days (car rentals, car sharing, test drives).  Take it for a spin and experience for yourself the hellos and goodbyes while you sing along in the silence of your EV.

An ownership decision (purchase or lease), may be affected by other factors that I may analyse in future articles.  But go ahead, drive an EV and experience the future of automotive mobility!






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About the author:  Jaime Requeijo has been a car lover most of his life.  As a business executive, he has been lucky to combine his passion with work in companies like Peugeot and LeasePlan.  Now he enjoys giving advice on mobility as a consultant and writing about his favourite car topics.

Disclaimer:   This article is not meant to be a technical paper.  Its purpose is to entertain and to inform people about the exciting new world of electric mobility that is coming upon us.  When mentioning technical aspect, I have tried to do adequate research and careful statement of facts.  I may have made some wrong technological assumptions or imperfect explanations.  If that were the case, my apologies.  Please feel free to contact me if you can help me improve the accuracy of the article (jaime.requeijo@gmail.com).  Thank you for reading it.  I hope you enjoyed it as much as I did writing it!







[1] There are many discussions on the overall emissions produced from a vehicle, including manufacture, usage and disposal of it.  And there are additional dilemmas on the potential emissions emitted in the production of electricity later used by EVs. But I would like to elaborate on those in future articles
[2] The internal combustion engine is, as stated in the main text, less efficient in transforming energy into movement.  Plus, it requires a heavy gearbox and add-ons like cooling and exhaust control that generate weight and cost.  The drawbacks which have left the electric engine behind in the past are linked to the inefficient means of storing the electricity on-board. 
[3] The paradox with noise is that it was also a means of alerting a pedestrian of an incoming car, so that he/she would not cross the street.  Regulators are forcing manufacturers to produce artificial noises (with speakers!) on electrical cars so they can be heard by pedestrians used to the noise of ICEs.  Let´s hope that it is just a transitional measure towards our silent cities of the future
[4] It is true that with modern turbo engines and sophisticated computer management, ICEs have improved a lot their power deliver.  But they still need a short gear to start movement due to the lack of power below 1500 revs per minute.
[5] Some Ford models are currently offered with an automatic transmission that has 10 forward gears.  Mercedes offers many with 9.  And 8 seems to be the prevailing number in upscale vehicles with larger engine capacity.
[6] Modern engine management and endless electronic sensors have allowed a decrease in the attention demanded from the driver towards the engine status and less cluttered dashboards.  Some sports cars still follow the old tradition of visualizing engine conditions.
[7] Modern automatic gearboxes take very good care of keeping engine revs at the optimum level for driving circumstances.
[8] Some people state that EVs and their need to recharge for longer period of times will give a much-needed boost back to the shopping malls.  I am unsure about the economics of including a charging station in a significant number of parking slots in a shopping area where most investment goes towards the commercial space.  But to be monitored.
[9] Remember that hydrogen+fuel cell electric vehicles do have similar recharging requirements to fuel based ones, so for them it may appear that going to a hydrogen station may be kept in the habits of their drivers.
[10] One of my favorite petrol head past times is to guess the cylinder count of an engine by its noise.  The deep bass burbling tone of an 8 cylinder is still a joy to hear.  An inline 6 cylinder has a unique balancing of its spark firings that gives a very refined noise.  A 3 cylinder has a racous, hard noise that can sometimes feel sporty.
[11] In my case, the eye openers were the Saab 99, Turbo and the, still in the market, Porsche 911 Turbo.  By the way, all 911s have an engine with a turbocharger, so it is just a badge to indicate a more performing one, not a unique engine characteristic.
[12] Please note that I am completely brand neutral.  I do not receive any support or sponsoring from any car manufacturer.  If I mention Tesla more frequently is because they are the most successful EV only manufacturer and by focusing on only electric they have made significant advances in most aspects related to EVs.
[13] One of my favorite learnings from school is one of the laws of thermodynamics which states that, in an isolated system, energy is not created or destroyed, it is just transformed.  A moving vehicle is constantly transforming energy.
[14] Tesla is still the champion of the range battle, with most of their models offering the capacity to drive for more than 500 kmts between charges.  They seem to still enjoy some early entry advantage over traditional manufacturers in the electric energy management that allows them to drive longer distances. 
[15] One kW is the equivalent of 1.34 hp.
[16] An interesting task, for the price of electricity usually incorporates many taxes and deferred investment charges that make its deciphering quite an ordeal.