Kylie Minogue presents a Lexus hybrid model
The car of the future will be a hybrid, writes independent researcher Schalk Cloete in the second part of a short series in which he compares costs and performance of various drivetrains. According to Cloete, improvements and cost reductions in electric motors and batteries will, ironically, help the internal combustion engine (ICE) through hybridization. These cost reductions combined with substantial engine downsizing can make hybrid drivetrains cheaper than conventional ICE drivetrains. In addition, future hybrids will avoid the large trade-off between power and efficiency of pure ICE cars, leading to broad consumer acceptance.Â
In the previous article, I outlined the main arguments why the internal combustion engine (ICE) will remain highly competitive with battery electric drive even as battery prices continue to decrease. This article will go into more detail about what these highly competitive ICE drivetrains might look like.
Even though the future is less certain for fuel cell vehicles, this technology will also be included in the discussion.
Future ICE drivetrains
Fact: The internal combustion engine (and any other heat engine) functions best under constant load. If the engine can constantly work near its optimal operating point, efficiency and longevity increase dramatically, complexity and costs reduce, and emissions control becomes much easier and cheaper.
Electric drive, on the other hand, is great for variable loads. Efficiency remains high, maximum torque is available even at low power output and mechanical energy can be efficiently recovered to electrical energy under braking.
Hybrid drivetrains aim to synergistically combine the internal combustion engine and the electric motor to fully capitalize on these fundamental characteristics. Even though hybrid drive has been around for about two decades, great room for further improvement exists. Continued cost reductions in electric drivetrains and battery technology combined with further development of ICEs especially designed for hybrid drive can lead to higher efficiency, lower costs and a better driving experience.
Power requirements during driving
To better understand the potential of hybrid drive, it is important to realize just how little power it takes to maintain constant speed (the role of the ICE) and how much power it takes to accelerate (the role of the electric motor). To illustrate this, three simple graphs are presented below.
The first graph shows the horsepower (hp) required to maintain a given constant speed for a car weighing 3050 lbs with a frontal area of 22 ft2 (typical Toyota Prius numbers) for different drag coefficients (source). Even at a speed of 60 mph, only 11-15 hp is required.
The thing that really takes many horses is acceleration. As shown in the graph below, accelerating even at a fairly modest rate equivalent to a 10 s 0-60 mph time takes almost an order of magnitude more power than maintaining speed at 60 mph.
Hills also require quite a lot of power depending on the gradient.
For these simple reasons, the hybrid of the future will have an engine that has substantially less power than the electric motor. The engine will be responsible for most constant speed driving, while the electric motor will provide the short bursts of larger power required by acceleration and steep hills.
The small-engine hybrid
Based on the above graphs, no more than 50 hp will be required for an ICE in a standard car. This ICE can then be complemented by a 100 hp (or stronger) electric motor with about 5 kWh of battery capacity to provide enough flexibility for longer periods of higher power (e.g. getting up a mountain pass).
Naturally, the worst-case scenario for such a car is running out of battery, leaving you with only 50 horsepower (which is still much better than running out of juice in a BEV). Under regular driving conditions, however, it will be near-impossible to exceed 50 hp for a sufficiently long time to drain 5 kWh of battery capacity without breaking several traffic laws. The battery can be recharged through the engine whenever fewer than 50 hp is required to move the car, through regenerative braking, or through a waste-heat recovery system.
The parallel hybrid configuration will be preferred to avoid the efficiency losses related to using an ICE just to drive a generator (series hybrid). In fact, a generator can be completely avoided since the motor can double as a generator in the parallel configuration. Furthermore, a smaller motor can be used since the power of the ICE goes directly to the driveshaft. With the electric motor having at least twice the power of the ICE, it may be most cost effective to let the electric motor drive the rear wheels and the ICE the front wheels, thereby allowing a downsized ICE transmission system. Given that the ICE will only need to drive the car at cruising speeds, the transmission can be quite simple and cheap.
In this system, the engine does not need to operate under rapidly varying loads. Current hybrids already employ an Atkinson cycle engine which boosts efficiency at the expense of performance at lower loads (where the electric motor does all the work). New HCCI engines could potentially drive engine thermal efficiency to the milestone of 50%, relying on hybridization to avoid ignition control issues under variable load. Diesel could even make a comeback thanks to easier emissions control from a largely constant power output and a larger battery pack allowing all electric drive in population centers.
How low could the cost go?
This powertrain performs well in a cost comparison with pure ICE and BEV alternatives. The graph below shows a breakdown of a future 150 hp car in three configurations. Cost assumptions are $50/kW for the ICE and transmission, $25/kW for the electric motor components (source), $100/kWh for the BEV battery pack and $200/kWh for the hybrid battery pack. A simple 2-clutch system to connect the ICE to the motor for charging the battery is assumed to cost an additional $500.
As seen above, the hybrid powertrain performs very well in this cost comparison. Maintenance costs of this future hybrid configuration will also be low thanks the the small ICE operating mostly at constant loads. Today’s leading hybrids are already showcasing this potential. For example, 5 years of maintenance of the Prius costs only $450 more than for the Leaf (while insurance costs are $330 less).
It will be quite a few years before such hybrids start to emerge though. Currently, an electric motor and power electronics cost almost as much as a gasoline engine and transmission, and batteries are still expensive (and unsubsidized for hybrids). Hybrids therefore typically have a small battery pack (~1 kWh) that limits the power and utility of the electric motor. The current cost comparison is given below to show that the proposed hybrid system would be significantly more expensive than a standard ICE.
Another important development that will enhance the hybrid configuration described above is waste-heat recovery systems. Technologies such as thermoelectric generators, electrical turbocompouding and organic Rankine cycles can convert a small percentage of the waste heat from an ICE to electricity to continuously charge the battery whenever the ICE is operational. This can allow the hybrid to keep the battery pack charged without requiring extra work from the engine.
Good technological development in this field can eliminate the need for any physical connection between the engine and the electric motor, thus offsetting some of the cost of these energy recovery systems. Additional engine downsizing allowed by the efficiency gains offered by these systems will further decrease costs.
Additional benefits
The future hybrid configuration with a greatly downsized ICE will bring at least two significant side-benefits.
Firstly, the hybrid configuration with a large electric motor will be more fun to drive than a pure ICE car. Currently, the hybrid image is still linked to the old Toyota Prius, which was very sluggish to drive. According to the vast majority of professional reviews, this stigma is already being altered by the new Prius and the Hyundai Ioniq. Future models will certainly continue this positive trend. As a result, people will start to buy efficient cars, not as a grudging compromise to help the environment, but simply because they are both cheaper and better to drive. Hybridization is already being used to increase performance in sports cars, the pinnacle of which is Mercedes’ 50% efficient F1 engine (see the YouTube video below).
Secondly, the moderately sized battery pack (~5 kWh) in the future hybrid configuration described above can also be charged from a regular plug overnight. Even though, on average, fuel costs for gasoline and electricity will not differ much for such an efficient hybrid vehicle, adding a plug provides fuel flexibility in the case of high oil prices. Even just a moderate number of such flex-fuel vehicles can provide enough demand elasticity to prevent fuel price spikes. For example, if oil prices start to rise outside of the normal range, everyone with these vehicles can instantly start displacing some of their gasoline consumption with electricity, thus reducing demand for oil and lowering the price.
Future fuel cell drivetrains
The fuel cell vehicle of the future will operate on much the same principles as the ICE hybrid described above. Given that the fuel cell is the most expensive part of the configuration, it will be kept to an absolute minimum size and will be mostly responsible for constant speed driving and gradual battery recharging. Acceleration and hills will be handled by conventional battery electric drive.
Future fuel cell costs are highly uncertain, but $50/kW appears to be possible. The hydrogen storage tank also represents a non-negligible cost of about $1500. To illustrate overall cost implications, the cost of a fuel cell drivetrain is added to the above graph.
It is shown that the FCV drivetrain is substantially more expensive than the ICE alternatives, but still cheaper than the BEV.
Where will the fuel come from?
Even though we still have lots of cheap oil (below), we will eventually have to move to more sustainable sources. CO2 emissions from the combustion of oil-derived fuels will also become a more important economic consideration over coming decades. The next article will therefore take a look at different ways of producing sustainable fuels for the long-term future.
Editor’s Note
Schallk Cloete describes himself as “a research scientist searching for the objective reality about the longer-term sustainability of industrialized human civilization on planet Earth. Issues surrounding energy and climate are of central importance in this sustainability picture and I seek to contribute a consistently pragmatic viewpoint to the ongoing debate. My formal research focus is on second generation CO2 capture processes because these systems will be ideally suited to the likely future scenario of a much belated scramble for deep and rapid decarbonization of the global energy system.”
This article was first published on our sister website The Energy Collective and is republished here with permission.
This article really depresses me, it’s as if the ICE is one of those creatures which grows new heads when you chop one off. It would have been useful if the author had included an estimate of the reduction in oil consumption under his plan, using the 5 kWh battery size and business as usual for car use, which seems to be his assumption; pushing serious electrification to the far future.
Well Herb, it’s all about physics really…So basically it’s the universe, that’s depresses you…In real life, electric cars (charging and self-discharge losses included) don’t have practical efficiency over 50% either, and very likely won’t ever have for a simple reason: Ohmic law. I know, I drive them regularly, and is very difficult to get much bellow 20kWh/100km. That’s 2l/100km diesel, which could be easily achievable with 50% constant efficiency ICE engine. And there’s a whole range of possibilities, not even mention in this article. So, oddly enough, good old mechanical engineering offers much more practical sustainable possibilities, than this delusional electromobility hype….
No question that the future holds a mix of hybrids and pure electrics. Our problem is not just building better cars, it is also reducing the roles of cars in our society (which is mostly not physics). I think my biggest worry is that the hybrids could be too successful at replacing our current cars with near functional equivalents (business as usual) which would reduce the pressure for the changes that we really need, while continuing to burn oil. The battery price reduction rate remains impressive and the auto companies seem to finally be pushing with pure EV development, so I am inclined to believe the widespread predictions that EV costs will cross ICE costs sometime in the late 2020s. The hybrids are likely to have a very useful but non-dominant market role.
There is reasonably high probability that our future will be self-driven taxis. Robotaxis. And they will probably be 100% EVs.
Most privately owned cars sit, unused 90% of the time or more. But we have to pay for 100% of the ownership, registration, and insurance. If we shared ownership with one other person we would pay only half as much in ownership costs.
Robotaxis are likely to serve far more than two people per day. If, on average, the car serves four people in a day then the cost of paying for a $25,000 car drops to $6,250.
If we step it up another level and are willing to share our ride with other people (which we do when we take a plane, bus, train, subway) then the cost falls further. Even allowing a profit for the taxicab company we could find it so incredibly cheap to ride in someone else’s EV that few of us would bother to own a car.
Why EVs rather than hybrids? All electric, not just the first 16 or 30 miles of the day and that means lower operating costs. Lower maintenance costs. A more reliable car over time.
Bob, you own a car. Most Americans do – I believe more than one. Predicting US citizens will give up their cars to wait around for taxis is not credible. People own SUVs to carry stuff, cars to shop, sports cars for the pleasure of lowering the roof and enjoying the day, motorhomes, off-road cars etc.. Yes, robo taxis will suit the elderly or disabled, but for most people robo taxis will be about as popular as taxis are today. Robo taxis will also be boring boxes on wheels. People want newish flashy cars on their drives.
Most people lease cars in the UK for ÂŁ250/month. Few are not concerned about the capital cost of car ownership.
As Important, car makers will not want to see sales of cars fall off a cliff face through robo taxi sharing slashing sales. They will ensure their products remain highly desirable and that owning a car remains the second most important purchase after a home.
I own a car and a pickup.
I’d give them both up in a heartbeat if I could call for what I want and have it show up in a reasonable amount of time.
“Wait around” shows a lack of understanding of ‘just in time’ delivery.
For example, let’s suppose you live in a suburban neighborhood where, on average, someone in your block wants to go somewhere between 10am and 11am on the typical day. The taxi company stations one car at your block. If demand is higher then they station two or more.
When someone gets in one of the waiting cars the fleet shifts one block so that the next closest car now take the position of the one that left. The fleet starts to shift as the first car leaves its parking position and heads to your door so you can get in.
The system is going to learn commute patterns and when the ‘big game’ is being played and adjust in anticipation.
Out here in the country where I live we might have a longer wait. Maybe ten or fifteen minutes but out here we just don’t run to the store for a bottle of milk. It’s an hour each way so we plan stuff in advance.
” People own SUVs to carry stuff, cars to shop, sports cars for the pleasure of lowering the roof and enjoying the day, motorhomes, off-road cars etc.. ”
Why own a SUV and be stuck with it on those days you’d rather be in a sports car or minivan? Just phone for what you want.
“ÂŁ250/month.”
I’ll bet a lot of people wouldn’t object to saving ÂŁ200/month.
“car makers will not want to see sales of cars fall off a cliff face through robo taxi sharing slashing sales.”
Of course they won’t. And they stop that how?
Most people, I would assume, would rather have a few thousand dollars per year to pay bills or do enjoyable things than to have a car sitting in their garage.
Fact is, we may see a huge bloodbath if robotaxi fleets hit the road. I can see the number of cars dropping to at least a third of what we now have. Tony Sebo has estimated a 90% drop in car ownership.
And it could happen very quickly.
Think about the people who have tight budgets and are often nursing along an unreliable car. Ride in a very dependable robotaxi for the cost of gas or less? Done.
About the people who just don’t enjoy driving or have trouble driving. They’ll switch.
People who are tired of dealing with traffic and parking during their daily routines. They’re in.
Robotaxis are likely to be a disrupter pretty much unlike any other disrupter we’ve seen to date. They could change the way we all live and decimate a large number of large companies.
Bob, I understand public transport in the US has never been popular, other than flying. Americans have been reluctant to use trains and buses, other than the poor with no choice. I’ve seen pictures of clogged up highways leading to and from LA. New York has the Subway, but the journey by road to say JFK is awful. Robo taxis might help reduce congestion in US cities, but the real answer is public transport.
To reduce congestion European cities dealt with the car problem decades ago. London developed underground railways in the 1800s and has one of the longest systems in the world. Shanghai and Beijing and Seoul have new systems that are longer. All electric powered.
London has a reliable bus system too with dedicated lanes. Some now are hybrids. Congestion controls keep cars out during peak times. Taxis tend to be used by the wealthier, but public transport is fine for most people. Also European cities see bikes as the way forward with dedicated routes and public bike hire schemes positioned around public transport hubs. This is London’s:
https://tfl.gov.uk/modes/cycling/santander-cycles
In major European cities current taxis might be replaced by robos but huge fleets of them would not be needed as public transport is cheap, convenient and underground railways faster than taxis. So Robo taxis will not be a disrupter in Europe because public transport is better than cars. It’s healthier too to walk to a station or cycle than be ferried around in taxis.
Outside of Cities, if someone has a parking space at their home most people will not give up the convenience of car ownership for the services of a robotaxi.
With the first point I agree. The geometric problem that case, no matter if BEV or ICE, self driven or robo car, need too much space when driving to be suitable in big cities is correct. public transport allows higher density of living and business, and higher density again improves business and incomes. And allows things to be handeled with lower CO2-emissions.
But It hink people will not keep their own car in younger generations. In the old generation, 60+, the car is still a status symbol, and this is something people do not want to loose. With younger peopl.e , 40- the car is not a status symbol any more. The rate of car ownership of younger people in big cities if falling significant. They will switch to robotaxi very fast. The habit of having a private car will vanish with the old generation.
Agree with all your points. I think of cars as a huge hassle and expense. I hate it that I have to own one, due to lack of alternatives, and I know I am not alone.
100% agreement. I have been managing without a car for the past 30 years in Autoland Germany, and enjoying it.
Apparently there is a new GPS chip which will be made available soon which will be accurate to a distance of less than a foot. (No link yet.)
If that’s true then self-driving becomes a piece of cake. All the car’s sensor system will have to do is to deal with the “Don’t hit anything” part of the job. GPS will take the role of lane markers and road edges.
Robotaxis, even self-driving personal cars, would mean far less congestion on city streets.
Just think how different busy streets would if there was no parking. Only a few places where the sidewalk narrowed a bit for self-driving cars to pull over and let people get in/out.
No people holding up traffic while they parallel park. No people circling the block looking for a place to park. No double parking while someone went in to get a pizza/whatever.
I suspect most stopping for passengers would be not on the main streets but just around the block on a cross street. There might be one place in the middle of the block for those for whom traveling a half block might a hardship.
A self-driving car has no need to park close to where you are going and then wait all day for you to return. If it’s a personal car it can move to a less crowded part of the city to wait. Perhaps get plugged in so that it can be part of the daytime dispatchable load. If it’s a robotaxi then it moves on to its next passenger or waits in an out of the way spot.
Parking space is not the problem in city centers, the problems are the road’s that’s why there are usually restrictions how many parking space is allowed to be built in new buildings in city centers. Cities would die of congestion otherwise.
My point of reference is San Francisco, Berkeley, Oakland, Santa Rosa, and Sacramento.
Parking causes congestion in those cities.
I was in SF day before yesterday. I got hung up behind people who were double parking a couple of times. And I have no doubt that some of the cars were circling the block looking for a parking spot. (I had to in Berkeley.)
Yes, the major through streets often do not allow parking. But you end up getting the turn lanes of those streets clogged up because someone can’t turn because the cross street is full of cars waiting for someone to finish parking.
Parking in San Francisco? Forget it. If you want to drive to dinner you better add an hour to your schedule. You’ll probably need it to find a place to park and then walk to your destination.
Parking in many European cities? You can’t walk on the sidewalk because people have turned them into parking lots.
@ bob wallace, well here nobody wiould use the car if he’d have to search that long for a parking space. Peuple takt metro, or subway or train or bus then instead, where the whole ride just takes 30 minutes. Share between public transport and car is 70:30 or 80:20 today, with walking and cycling included, the share of car transport in the town center is below 20%, but still consuming 90% of available space.
dense and vibrant city centers are public transport teritory, everywhere. Does not work ortherwise geometrically, only with walking and cycling, but that oly for smaller distances. (2km, 12km)
You need to remember that the US is a much newer country than those in Europe. And in my lifetime the population has almost tripled. .
Not that many years ago you could get around most US cities quickly and easily find parking places. Driving your own car was very convenient and we weren’t concerned about climate change.
Only in the last ~20 years have some cities reached the point at which public transportation systems have been needed due to congestion.
European cities grew up long before the car existed. The London Underground began service in 1863. The Paris Metro in 1900.
The Ford Model T started production in 1908. Now large cities were modest in size. Los Angeles had about 300,000 people. The population did not hit 3 million until about 1970.
In the 1980s I used to drive to SF on a whelm and congestion was never a problem. Parking was easy. Worst case, you might have to walk a block or two from where you found on street parking to your destination.
My hazy memory recalls crowded city streets and people parking on the sidewalk in Europe in the 1970s.
Robotaxis open up the opportunity for “spontaneous carpools”. Sharing rides.
If you’re willing to share the other seats in the robo in which you are riding your cost should drop proportionately.
For someone who commutes to work saving 50% or more of the cost of commuting would be fine for lots of people.
The current problem with carpools is that it takes a lot of arranging. If someone needs to leave early/late, is sick, has an errand they need to run, etc. problems arise.
If you want to go from your door to your workplace the system can put you on route with others making roughly the same trip at the same time.
This, I suspect, will reduce the number of vehicles on the road.
This is more likely with robotaxis in minibus-arrangements, which provide public service in significant higher frequency than todays busses, where by far the highest amount of cost come from the driver. This also allows more routes. The car pooling would require that you are at exactly the right time at the right place, otherwise the others have to wait.
A minibus bus-line would send e.g. a 9 seater every 5 minutes instead of a 50 seater every 30 minutes. Which allows you to travel flexible. If you miss one bus by being too late, the other is already aproaching.
Yes, driverless vehicles scheduled by a central computer open up all sorts of variations from (possibly) tiny single-seat vehicles to four passenger cars to 60 passenger buses.
A 1, 4, 12, 20, 60 seat vehicle can be dispatched to move people as works best.
In Bangkok there are mini-vans that run from the city center to specific areas outside the center, even towns outside of BKK. They cruise the main bus stops until full and then they zip off to their destination, miles away. Once there they deliver people to where they are going (within reason).
We could easily see smaller vehicles bringing riders to places where they would transfer to larger vehicles heading to different destinations. And then people moving from the large vehicle terminus to a vehicle that takes them to their door.
This is how we reduce congestion. We move people in as large a vehicle as possible as long as most seats are full.
We ‘encourage’ people to take the largest vehicle by making them comfortable (no sardine packing – everyone gets a seat) and with differential pricing.
Largest vehicles cost the least per mile to ride. Solo in a four seater would carry a cost premium.
The battery price reduction has it limits, (due to fundamental laws of physics and material properties), and we are almost there. For the same utility (in economic terms), they will never cross the price line with ICE hybrids…sorry to burst your bubble.
Material cost for lithium-ion batteries is about $60/kWh. And that cost could fall as we start using larger quantities of the materials and enjoy economies of scale.
Take lithium, for example. Tesla appears to have arranged for supplies from highly concentrated brine close to their battery plant. An efficient system of refining and transporting a relatively short distance could easily make lithium cheaper.
We know that GM is paying $145/kWh for cells which suggests that LG Chem’s production cost is in the $120 to $130/kWh range. That tells us that there is a lot more room for battery cell cost reduction.
As a commodity the cost to manufacture a cell should be only about 10% more than the cost of materials. We could see cells well under $100/kWh.
With EVs using less than half as much energy per mile as the best hybrid I doubt hybrids are going to be able to fill that gap. And it’s highly unlikely that it will be cheaper to manufacture an ICE with all its moving parts than a bunch of simple to manufacture battery cells.
Good luck with your hybrid dreams. Let us know when someone produces a reasonable sized hybrid that gets 100 MPG.
BTW, the EPA recently gave the Tesla Model 3 with the 80 kWh battery pack a 334 mile city/highway range. 0.27 kWh per mile.
At 33.4 kWh per gallon of gasoline a 50 MPG hybrid is using 0.67 kWh/mile. That’s 2.5x as much energy per mile as the Tesla 3.
Physics doesn’t require we use Cobalt,Copper or Nickel for automotive batteries.
By today’s standards, we could have salt cheap solid state batteries in 20 years.
I suspect hybrids might be something that well-off people own, while all the po’ folks go with the cheap, digital solution.
I really doubt that the rich will bother with hybrids.
Right now they can buy a Tesla that has a 315–335 mile range. They can recharge over lunch.
Charge rates will increase.
Self-driving cars will drop everyone off at a restaurant/whatever of their choosing, take themselves for a charge, and then pick everyone up when they are ready to leave.
Tesla Destination Chargers recharge at a rate of 5 miles per hour so a 10 hour hotel stop will restore 500 miles.
Battery capacity will almost certainly increase. If it’s really needed.
Then, why drive if you’re rich? Going to Miami Beach from NYC for the winter? Fly. Take a robolimo to your condo on the beach. Your car will drop you off at the airport, drive itself down, and be there when you wake up in the morning.
Or one robolimo drops you at the airport, and the next one picks you up at the airport.
Or if you don’t have problems with other people around you take a robo minibus and talk on the wy, read, write on the smartphone etc.
why bother with driving or loading?
And, if the state would be willing to close some gaps in the fast net, we’d have comfortable fast trains here for the distances between 200 and 1000km. take some public transport (robolimo, robobus, robotram, romometro ) to the station, travel 40min to 4 hours to the target, and go further with public transport to your target. what use shoule a hybrid car be on that journey? who drives a hybrid car by free will when there are fast trains?
Martha,
History with the Tesla Model S suggests the opposite is true. It very rapidly outsold all of the top of the line European luxury cars, demonstrating that those to whom money is not a barrier prefer all of the performance and other benefits of pure EV vehicles, and will not put up with the substandard driving experience (e.g., noise, vibration, pollution, etc.) and inconvenience (requirements for oil changes, visits to the gas station, etc.) of a hybrid. The perceived (as well as the actual) inferiority of gas and gas hybrids (as confirmed by the early adoption of EVs by thought leaders) will help to further accelerate the transition to pure EVs.
That may be true in ‘Greenie’ California but is not so in Europe. (except Norway which is an exception driven by subsidies).
The Model S is too expensive so sells in very small numbers in Europe, like all EVs. Real luxury makers like Jag., Audi, Merc. and BMW are a few years away from offering a true luxury BEV – there isn’t the demand. Instead they offer hybrids which also sell in small numbers. European car makers have focussed on low emission diesels which are better than petrol. There isn’t the demand for plug in vehicles, European car makers are only having to push them because the EU will fine them if their fleet sales emissions are >130g/CO2.
ICE bans are decades away and in the UK hybrids will not be affected.
Green dogma forcing BEV’s over hybrids will not be prevail. The issue is emissions which both hybrids and BEVs can address.
If you start with 100 kWh of electricity and use it to operate an EV you will lose about 10% during battery charging. About 10% of the remaining 90 kWh will be lost during operation.
Of the original 100 kWh roughly 80 kWh will be turned into kinetic energy. EVs are extremely efficient.
You’re going to toss about half the energy in that 2 liters of diesel away as waste heat.
The most efficient hybrid we have get about 50 MPG. EVs are easily twice as energy efficient. The Tesla S versions run from 98 to 104 GPMe.
No, Bob, they’re not…not in the real life…You don’t understand the difference between ideal, optimal and real life efficiency…The efficiencies you predict are completely unrealistic, since you would need very low currents in the system. That means you’ll have to charge extremely slow and drive extremely gently to the point of becoming an obstacle in the traffic.
The most efficient hybrids on the other hand are today not nearly close to the limit, of what is achievable with modern engineering and materials (I won’t go into details now, since it would require to much time, but some of these points were addressed in the article). Electric cars on the other hand are, since they rely on the conductivity of materials possible in this universe. We have only so much elements in this universe on our disposal to achieve a voltage potential, and we are already there. There’s also a co-optimization problem between electron and ion conductivity, which means, that you can have either either low (internal) resistance high specific power or high resistance low specific energy battery. But not both! This is explained by so-called “Ragone plot”. Another option are ultra-capacitors, but are suitable only for high-power application with specific low-energy demand requirements and have typically high self-discharge rate. Which brings us back to hybrids. There are also mechanical (hydropneumatic) options , which might be even better. And that’s about it.
Rod, charging efficiency is well know as it electricity use per mile.
We are far from the theoretical potential of lithium-ion batteries.
[censored again – no personal attacks!]
I wonder what I might have said.
Might I have reacted to this incorrect information?
“You don’t understand the difference between ideal, optimal and real life efficiency…The efficiencies you predict are completely unrealistic, since you would need very low currents in the system. That means you’ll have to charge extremely slow and drive extremely gently to the point of becoming an obstacle in the traffic.”
The fleet average mileage for Volts is over 100 km per liter.
Correction: I happen to get 100 km per liter (without much trouble) but the fleet average is more like 50 to 60 km per liter depending on the vintage. I’d argue the continued build-out of charging infrastructure coupled with an expansion of the EV range to 100 km will push mileage down towards if not past the 1 liter/100 km mark in the not too distant future.
One of the clear problems with the author’s article is the limitation of the battery size to 5 kWh. There are two problems here actually. First off he’s speaking in terms of kWh when he should be talking about electric range. Second off, the optimum electric range depends on the cost of batteries/gas and the availability of charging infrastructure. It’s quite possible for a 50 mile battery to deliver a fleet average electrification factor of 80% with the right amount of charging infrastructure. Diminishing returns will smother the incentive to add electric range at some point but 5 kWh (15 to 20 miles of range) is far too conservative.
S. Herb,
Don’t be depressed, other recent independent (i.e., not funded by the oil industry) reports suggests that Schalk Cloete is simply wrong. For example, a recent report out of the UK found that a majority of UK motorists expect to be driving an electric vehicle within five years. See: http://www.totalev.com/electric-car-news/77/press-release-uk-electric-car-pole-position See also: https://www.bloomberg.com/news/articles/2017-07-06/the-electric-car-revolution-is-accelerating, https://eandt.theiet.org/content/articles/2016/12/electric-vehicles-poised-for-wider-adoption-breakthrough-within-five-years/ and https://www.rethinkx.com/executive-summary/.
Some of the factors highlighted by other studies, and which the Cloete report fails to account for, include: (a) the ongoing exponential reductions in the costs of electric drive trains and batteries due to learning effects (for example, the cost of batteries is down 80% in six years); (b) the much greater costs, even at scale, of building, servicing and maintaining vastly more complex hybrid drive trains (which require oil changes, air filters, oil filters, exhaust systems, and many other service items which are not required by BEVs); (c) the relatively small percentage of the price of electric drive trains which are accounted for by raw materials costs (meaning that further massive cost reductions are expected); and (d) the various legislative initiatives, based on the predictably falling costs of electric vehicles and the health and environmental costs of ICE vehicles, in many countries, states and cities, to outlaw the sale of ICE vehicles in the coming decades.
Except for small round town cars, hybrids will be preferred unless there is a huge break through on battery costs or battery technology. German car makers could have made BEV cars to compete with Tesla but haven’t bothered. They are concentrating on hybrids for good reasons.
“German car makers could have made BEV cars to compete with Tesla but haven’t bothered. They are concentrating on hybrids for good reasons.”
That might be reality in a fact free world.
[censored – personal attacks or innuenduo are not allowed, please confine to arguments]
Any even-handed independent scientific work would have discussed, some or all of the following considerations:
The inherent low limits on heat engine efficiency which unavoidably result from the application of the second law of thermodynamics.
The further vast energy inefficiencies embedded in the oil industry supply chain.
The inherent inefficiencies in the production storage and use of hydrogen, relative to the direct storage and use of electricity.
The implicit and explicit subsidies of oil and gas which are artificially suppressing the price of oil (including not only cash subsidies and tax expenditures, but the costs associated with GHG and particulate emissions) all of which are being increasingly challenged in the wake of the Paris Climate Agreement.
The ongoing reductions in the costs of electric drive trains and batteries due to learning effects (for example, the cost of batteries is down 80% in six years).
The much greater costs, even at scale, of building, servicing and maintaining vastly more complex hybrid drive trains (which require oil changes, air filters, oil filters, exhaust systems, and many other service items which are not required by BEVs).
The relatively small percentage of the price of electric drive trains which are accounted for by raw materials costs (meaning that further massive cost reductions are expected).
The benefits to the electrical power grid, including dispatchable demand and potentially dispatchable supply, which may be provided by a large BEV fleet, and which can help to facilitate the further penetration of renewable energy.
Legislative initiatives, based on the predictably falling costs of electric vehicles and the health and environmental costs of ICE vehicles, in many countries, states and cities, to outlaw the sale of ICE vehicles in the coming decades.
I get it, your dream car is a PHEV like Chevy Volt. But there is a catch. Real world owners of this car shortly start to hate when the ICE is started. They are doing incredible thing just to postpone that moment.
Jan, I agree with you. All hybrid owners I know, can’t wait to dump the ICE part of the vehicle (and to graduate to a pure BEV for their next vehicle). We made the transition five years ago, and after 140,000 BEV km (including three trips from Canada to Florida) have found the cost, performance and driving quality advantages of BEVs to be so compelling, that we can’t imagine regressing to a highly complex and maintenance intensive hybrid.
I believe that hybrids will help to convert drivers from ICE to BEV in no more than a single vehicle. But there is no long term future in hybrids.
Thanks for confirmation. There is another catch about PHEV. Even with smallish (f.e. 50 km) pure electric distance of Chevy Volt, owners cover with this propulsion about 80% of all distance travelled. So, 80% (or >90% with 100km electric distance) of the kilometers travelled, the several hundred kg weighting ICE co. is just a useless dead weight.
Moreover those ICE powered distance is consumed during occasional (1-3x per year) long road trips.
That brings the idea to have the ICE part of the propulsion removable or to be attachable as a trailer. That device may be in a garage or for rent. Ready to be used during those several days of the year when needed.
This is part of a learning process. People have to learn how rarely a ICE is of use in such a hybrid car to make a good decision when buying the next car.
A problem with PHEVs and their smaller battery pack is that you are cycling the batteries far more often than if you have a larger battery pack EV and take it down only a small amount per day, refilling at night.
Somewhere down the road you may find yourself driving an almost ICEV because your battery range is shot. Or you may be paying for a new set of batteries.
Jan, In my immediate circle of family and friends I can point to at least six individuals who have transitioned from gas to hybrid to BEV (in some cases with a PHEV in between the hybrid and BEV). A friend who was very happy with his Volt recently replaced it with a Bolt and is delighted with his ability to take longer trips without having to purchase gasoline.
With the wide variety of longer range, lower cost, BEVs coming onto the market from Japanese, Korea, Europe, Chinese and US manufacturers, and the exponential growth in the charging infrastructure, it seems inconceivable that PHEVs will play anything more than a brief transitional role.
Just noticed. You put a thumb on the scale by using a 80 kWh battery pack for your EV comparison.
The new Tesla 3 has a 50 kWh pack that gives an EPA rated all-electric range of 220 miles (350 km). (EPA ranges are more realistic than the European range number.)
That’s plenty for almost all drivers.
We already have hybrids with itty bitty motorcycle engines.
The BMW i3 Rex.
It sucks.