EV Recharging: Not The New Refuelling, Think Smartphones and Recharge While Sleeping.

Testing of a wireless charger with potential to charge a Porsche Taycan to 80% in 10 minutes.

There are anxieties about the idea that cars will all become electric. In fact sometimes these anxieties even generate hostility!

But yes, motor vehicles will become electric, not because of green movements, or because of government incentives, but because they will be better and cheaper.

Those incentives and the ‘green’ stuff does help get the ball rolling, but EVs will only take over if and when they become cheaper than petrol, gasoline and diesel vehicles, which wil be by 2025 for new cars, and later for used cars.

While, as usual, the early adopters pay a premium, the rest of us should use the time to prepare, because the biggest winners, will be those who are ready so they don’t need to be anxious.

Key Concepts: Recharge Like A Phone While Sleeping, and Range Per Hour.

A Complete Rethink: Think Like Mobile Phone Recharging, Not Refuelling.

A first, it seems recharging just replaces refuelling, and all else stays the same, but that does not reflect reality.

In fact, just like with a mobile phone, electric cars are almost always charged at home. In fact, for a normal person, most times you would charge your car other than at home, you will also be charging your phone away from home, as this will only happen when you are be on a road trip.

Only charging an electric vehicle at fuel/charging stations, just as you would with a petrol, gasoline or diesel vehicle, will result in higher running costs, less convenience, and more scope for things to go wrong.

A rethink is required. One of the best ways to imagine see that rethink comes courtesy of an insightful article looking from the other side. What would be required as a rethink for a person accustom to electric vehicles, replacing their an electric vehicle with a gasoline/petrol vehicle?

  1. I have heard that petrol cars can not refuel at home while you sleep? How often do you have to refill elsewhere? Is this several times a year? Will there be a solution for refuelling at home?
  2. Which parts will I need service on and how often? The car salesman mentioned a box with gears in it. What is this and will I receive a warning with an indicator when I need to change gear?
  3. Can I accelerate and brake with one pedal as I do today with my electric car?
  4. Do I get fuel back when I slow down or drive downhill? I assume so, but need to ask to be sure.
  5. The car I test drove seemed to have a delay from the time I pressed the accelerator pedal until it began to accelerate. Is that normal in petrol cars?
  6. We currently pay about 1.2p per mile to drive our electric car. I have heard that petrol can cost up to 10 times as much so I reckon we will lose some money in the beginning. We drive about 20,000 miles a year. Let’s hope more people will start using petrol so prices go down.
  7. Is it true that petrol is flammable? Should I empty the tank and store the petrol somewhere else while the car is in the garage?
  8. Is there an automatic system to prevent gasoline from catching fire or exploding in an accident. What does this cost?
  9. I understand that the main ingredient in petrol is oil. Is it true that the extraction and refining of oil causes environmental problems as well as conflicts and major wars that over the last 100 years have cost millions of lives? Is there a solution to these problems?

For this page, #1 is the most relevant, and conveys the important concept that “recharging while sleeping” is the normal, and going to a charging station should be an exception that only happens a few times a year.

Normal Life Means Recharge While Sleeping.

Charging while sleeping, the ideal for an electric vehicle, will normally mean that overnight, vehicle is recharged enough replace whatever charge was used during the day, or at least ensuring more than sufficient charge for the entire next day. For most of us, this is just like what happens with a mobile phone.

But then, some phones just don’t last all day if you watch lots of videos or some other battery intensive activity and could need an emergency top-up. Same with electric vehicles. While all early vehicles had terrible range, now even the least expensive EVs that sell for around US$5,000 in China can get at least 250km (150 miles). Given a normal person averages less than 60km per day, most days cars are used just for local transport, but for a road trip or for an ’emergency’ when the driver just didn’t get to recharge as they should, rapid charging at charging stations will be the solution until in road wireless charging is available.

Charging Stations and Rapid Charging: Emergencies and Road Trips.

Use of rapid charging should be very rare, unless a person either:

  • Has an unsuitable car.
  • Road test cars as an occupation, or has other commercial use.
  • Has free access to rapid charging, or doesn’t have the ability to charge at home.

A car needing rapid charge, is in some ways like a person who did not get enough sleep last night, and as a result needs a ‘catnap’ to get through the day. Either the day is unusually tiring, or the person is not getting enough sleep. Frequent use of rapid or emergency charging creates problems because:

  • Rapid chargers are additional infrastructure that comes at a cost, increasing the cost of electricity.
  • Using a rapid charger frequently will reduce battery life.

For lowest running costs, best battery life, and the best experience from an EV, almost all charging should be at home and rapid chargers only used in exceptional circumstances.

Forget Full Recharge Time Which is just a distraction, Range Per Minute is what matters.

A bigger battery will take longer to fully recharge, but typically less time to charge for a given distance. While all early EVs had so little range it made little sense to do anything but a full rechange, which is why “full recharge time” was at one time useful information. Now there are vehicles like the Lucid Air with 800km range and vehicles such the Aptera being released with even up to 1,600km range. Of course there are still vehicles with very little range as well, but it makes no sense to compare time from empty to full of a vehicle with 1,600km of range to that recharge time of a vehicle with just over 100km of range.

While with ICE vehicles, it usually makes sense to use most of the fuel in the tank, and then ‘fill the tank’, this is not the normal pattern for every day use of an EV.

The normal ‘charge while sleeping‘ will, most days, only need to replace less than the typical 100km (60 miles) of range that was travelled that day. Even on a road trip, when using ‘rapid’ charging, you need enough charge to comfortably get to your next charge. Using latest technology that can charge 200km (120 miles) in 5 minutes, 10 minutes charge should usually be more than enough, and you would only fully charge if it is convenient at that time. Picture yourself, 100km from you destination and needing sufficient charge to complete your journey. Would you think “I have a large battery that provides 800km range, so I must fill it and I wish I had a smaller battery that only provides 300km range!”.

What does matter, is how long it takes to add range. This can be stated as ‘range per hour’ for slow charging, because when ‘charging while sleeping’, it is easier to think in hours, but for rapid charging, it is better to think in ‘minutes per 100 km’. In practice, there are two measures:

Only how long to add range matters, not %
  • Range per night or per hour, for ‘charging while sleeping’.
  • Range per minute, for the emergency high speed ‘rapid charging’.

Consider which would you rather have?

  1. A car with a small battery and a range of only 100km (60 miles), that fully charges in just 20 minutes, but have low range.
  2. A car with a large battery and a range of 800km that fully charges in 30 minutes, but will travel 400km from 10 or even 15 minutes of charging.

Surely option 2 is the better car to have, even though a full charge does take longer. As battery capacities continue to increase, the time for a full charge from ’empty’ to ‘full’ will become relevant even less often. What really matters, is how much range can be added in a given period of time, or how long will be needed to add the range required.

EVs Redefine ‘Road Trip Ready’.

There are two experiences of using a car to get people from a to b:

The links provide further explanation but think fetching groceries from the local supermarket as clearly a local trip, and a weekend getaway is usually clearly a road trip. Often the lines get can be blurred. What about a rare visit to a special farmers market 3 hours away? Or a weekend getaway in a location just 2 hours away? But generally it is common to have this idea of some trips that requiring more from the vehicle that others.

The difference between the trip can be so different that a vehicle can need different preparation, and some vehicles are only suitable for ‘local’ trips. A vehicle can be still suitable for ‘local trips’, even though some of following limit use for ‘road trips’:

  • I wouldn’t want to be driving that on the highway.
  • The tyres should be checked or replaced before the car goes on a road trip.
  • A service is due soon, so should happen before the road trip!

How the vehicle is driven changes between local trips and road trips, but with an internal combustion vehicle, the refuelling process stays exactly the same, even if the other things done when refuelling change.

With an EV, local trips charging is mostly from a home charger using an AC only cable, and could even come from solar power, and takes place at leisure, either overnight, or while parked for extended periods. But with an EV, road trips require the use of a charging network, use DC rapid charging, often costs more due to the need to pay the charging network, and can even involve forward planning to organise optimal pricing.

The very first electric cars were totally unsuitable for road trips. There are still some EVs that are unsuitable.

A trip requiring recharging while on the trip becomes clearly a ‘road trip’ that is different in nature from local trips.

EV Charging Introduction: The Three Charging Levels.

Why 3 levels of charging?

It may feel like a new world where there is more than one way to refuel, but in practice, even with gasoline vehicles, refuelling on a long trip is different as it is often combined with a rest stop, perhaps with some food or fast food, and has a different feel than filling up during a normal week while commuting.

Refuelling an internal combustion engine vehicle is not necessarily convenient, but it is always fast.

Recharging an electric car, you should avoid ‘fast’ most of the time, as rapid recharging is more expensive, less convenient, and should only occur on road trips or in exceptional circumstances. The trap is, rapid recharge feels most like the familiar refuelling of an internal combustion engine, so it can feel like it should offer the familiar. However, for electric cars, recharging at home is more convenient than the familiar refuelling, and rapid charging is slower than the familiar refuelling. An EV that is only ever rapid recharged is a worse experience than an ICE vehicle, and when an EV owner recharges while sleeping the EV experience is an improved experience. The best EV experience requires using the most appropriate charging level for the occasion.

There are several articles on the charging levels already available, but such articles are often a little misleading, as they are often sponsored by people selling home chargers with a motive to upsell chargers.

It is important to consider that wireless charging is real, just becoming available, and will become more important over time. Wireless charging is perhaps a fourth level.

Level 1 Charging: despite the myths, a great way to charge an EV.

Level 1 charging is charging a car using from a standard home mains power socket. For most people, this is all you need when charging at home. Level 1 charging will normally add around 4 to 5 miles per hour of range using USA/Canada/Mexico/Japan style 120v power, or 10 to 12 km per hour (6 to 8 miles per hour) in the rest of the world where mains power is 240v.

Home charging is not about road trips, as during a road trip you are not normally at home. Home charging is about ‘recharging while sleeping’ after a typical day driving, and for most people only needs to be able to add less than 100km or 60miles of range each night.

More detailed calculations as explained below reveal what the 5% of people who need more then 100km or 60 miles of range a level 1 charge will add at home, but unless you fill the tank of your gasoline car every day, you don’t need to fully charge your electric car overnight every day either. Level 1 charging is every day use, because unlike a gas station, you normally visit your home every day.

There is myth that charging standard mains socket is too slow. Yes, if you car has good range, it will take well over 12 hours to fully charge the battery this way, using level 1 charging, but you don’t need to fully charge your battery from discharged at home, there are rapid chargers for when you need that. Fully charging is normally only needed during road trips, and road trips don’t normally happen while you are at home. See this quote from ‘fully charged’.

For the occasional long-distance electric car journey, now I say occasional because most people don’t drive 350 miles in a day, regardless of how many times I get told that on twitter, statistically, it’s inaccurate. Its about 25-30 miles a day is the average car journey, not only in the UK but in every European country and North America. In North America that is the average and yet you could drive 3,000 miles across the United States, which people have done, and people do regularly, but not that often.

Robert Llewellyn from Fully Charged.

Level 1 charging usually adds up to 2.4kw in 240v countries, and up to 1.6kw in 110v countries.

Level 1 charging from a standard mains socket is the most useful charging option, for most people, most of the time.

Level 2: Faster charging while sleeping.

Level 2 charging is high speed AC mains power charging, and requires special high power home or commercial power sockets. In the US or 120v countries, such sockets may be available for laundry appliances, and in 240v countries, 3 phase power sockets may be needed for fastest charging.

While Level 1 charging can charge overnight after a ‘normal days’ driving, Level 2 charging provides for ‘charging while sleeping’, even when all battery capacity has been used during a single day and a full charge will again be required the next day. Level 2 charging is relevant when:

  • Stopping overnight at accommodation during a road trip.
  • A vehicle is often used for sequential days of all day driving, including:
    • Commercial vehicles such as taxis, couriers, or delivery vehicles.
  • It is only practical or convenient to charge at home every 3rd or 4th day.
  • There is a short window of time when electricity is least expensive.
  • Less efficient vehicles including large off-road vehicles.
  • Vehicles with a long and high speed daily commute, beyond level 1 overnight recharge level.

Level 2 car charging can be limited to 7kw, 12kw or sometimes as high as 22kW or even 40kW.

Level 2 chargers also have different capabilities, and how chargers are typically only 7kW in 100v countries, and up to 22kW in 240v three phase countries. For most charging home requirements, 7kW or even 3.7kW should be plenty.

This site quotes range distance added per hour as: 3.7kW= 20km, 7kW=40km and 22kW=120km, which should be indicative.

Level 3: Rapid Charge for road trips, and emulation of gasoline/petrol/diesel refuelling.

Rapid charging is needed when ‘charging while sleeping’ isn’t practical. Ideally, EVs would have sufficient range to deliver what ever is required even if driving all day, and thus always able to be charged after the day is over. Reality is, there will always be times when a way extending a vehicles range is required, although in future this may be through road based wireless charging.

The goal of rapid charging is the highest possible transfer of power possible into the vehicle, and this means the greatest stress on all electrical systems. Rapid charging should not be needed often, but when it is needed, you tend to want it as fast as possible.

AC/DC?

Charging quickly requires high voltages and currents. Normally in homes there is high voltage AC with is suitable for charging EV batteries, but the DC power normally used is simply not powerful enough to help with charging an EV battery. This makes AC power the preferred power at home. The DC power used to charge EVs, is all about rapid charging using hundreds of volts, and this type of power is only available at high speed chargers. This DC is nothing like the lower voltage DC associated with batteries in flashlights at home! As a general guide:

  • AC: charging at home or lower speed charging, or charging small batteries such as those of PHEV.
  • DC: Newer, specialist rapid charging currently capable of delivering 350 kw.

Comparison: Gas/Diesel Range & Refuelling vs EV Range & Charging.

What the? Different Types of Refuelling/Recharging?

The only place you can refuel a petrol or diesel vehicle is a ‘gas station’ (or ‘petrol station’ for those outside the US). A specialist location for refuelling. Having made a trip to a gas station, financial constraints aside, you may as well fill the tank as it will make little difference as the visit will take almost the same time to fill the tank or half fill the tank, unless the vehicle is very large.

Internal Combustion Engine Vehicle (ICE)Electric Vehicle (EV)
Road Trip Important SpecificationDistance Between RefuellingTime To Add Range at Fast Charger
Normal Use Important SpecificationDays Between RefuellingRanged Added Overnight
How To Refuel/RechargeSpecial Stop at gas stationNormally just park at home.
On Road trips at charging station.

Periodic ‘Home’ Refuelling/Recharging: Fuel/Charge for ‘Local’/’Urban’ Use as Local Transport.

Home Charging Replaces Periodic Refuelling.

With an ICE vehicle, around once or week or so for most people, a stop off for a refuel is required. These refuel stops are more mundane that the refuel stops on a road trip, and almost never involve a bathroom break or a meal. Some people sometimes grab a quick snack or emergency groceries. It is most common to fill the tank, but it the price is wrong, for other reasons, it is not universal to completely fill up.

The EV equivalent is charging at home overnight, or for some people, charging at work during the day. This is recharging using the long windows of time most cars spend parked, and provides optimum charging without the driver waiting while the car charges.

In normal use outside of road trips, most private cars spend most time parked, so there there is lots of time available for charging.

Home Charging Typically Only Needs To Add 60 km or 37 miles Of Range Per Day.

The average motorist travels 13,500 miles or 22,000km which, divided by 365 gives an average of 37 miles or 60 km per day. So if you started with a full charge, on average if you can add 37 miles or 60 km range by charging at home, then you would never need to charge elsewhere, other than on days you are travelling further than the full range, which for a car with 250 miles or 400km, typically will mean a day with around 4 or more hours just driving.

For most electric car owners, “charging while sleeping” is so normal, that there may be months and months between visits to a specialist charging station. Unlike visits to a specialist charging station where the driver may have little else to do while it charging just as when refuelling in ICE vehicle, recharge at home is plug in when you get home, and unplug next morning or before leaving. It doesn’t matter how long it takes. In fact, with wireless home charging, there are already some cars where you do not have to do anything, and charging just happens while your are parked.

Who Needs A Home Charger?

You can buy home charging stations for most electric vehicles, even though in practice, for most situations, charging from a regular electric socket should be all you would even need at home, particularly outside of Japan or North America as in most countries the regular voltage is 240v. Almost 2021 models EVs have a range of at least 350km of urban range, which means only needing a full charge overnight at home on occasions you need to drive around 300km on each of two consecutive days. That is, arrive home having used the full range one day, and need a full recharge to again be able to have full range the next day. Given that average of 60km per day most of us drive, two consecutive days of driving 300km are rare, and two consecutive days with that number hours driving almost always involves staying somewhere other than home at least one night, and needing to charge at a charging station anyway. When on a road trip you typically do need fast charging, but a fast charger back home will not help.

The main benefit from a fast home charger that is allows only every bothering to plug in every 3rd or 4th day, or in many cases, perhaps once per week instead of every night. Why not charge a little every night? Perhaps the ‘home’ in question a second home, or there is one place for charging shared between several cars?

It could be that for some people, it is too hard to change a mindset that ‘refuelling’ is best left until ‘the tank is getting empty’, so to plugin in every time they are home, even if the battery is quite full, means breaking a pattern established over years and years.

While the provision for fast charging is essential to electric vehicles on road trips, it is not critical for charging at home.

Home Charing Times Without A Home Charger via the “granny cable”.

The cable for charging from a regular mains socket is sometimes called the ‘granny cable’, particularly by car reviewers, who like travelling salesmen, rarely get the opportunity to charge at home.

Some stats, note that US, Canada/Mexico and Japan and have 120v power at home, while almost all other countries have 220-240v. Confusingly, US/Canada/Japan can also have 240v charging, but as this is from ‘3-phase’ and not from a regular power socket, there is usually more current available than from a regular socket in 220/240v countries. When 220-240v is listed below, it is regular home 220-240v as in UK, Europe, Asia, China, Australasia, Africa, not 3 phase power in the US etc.

Charging at home data (12 hours ‘overnight’ figures where possible)

I may add more examples to this table over time.

Road Trip Refuel/ Recharging: In Reality Infrequent, But The Reason For Fast Charge Specs.

How often do you go on a ‘road trip’? A ‘road trip’ means either, at least one entire day mostly spent driving, or one or more nights away from home. For most of us, these do not happen that often, but as with the speed specification of with a Ferrari that doesn’t actually get driven fast often, how fast an EV can be charged from almost empty is the specification that gets a lot of attention. For most people, fast charging is only every used on road trips, but it does matter, because historically it has been really slow, and it is still not perfect.

We may not give it much thought, but even with an ICE vehicle, road trip recharging can be different than filling up when not on a trip. Travel is most often with a group or the family, and the stop may also be a bathroom stop, and a meal break. There is usually a different feel then fitting in the periodic refill into local trips. With an EV, that difference increases, because this is normally the only time you use a fast charger.

When refuelling an ICE (internal combustion engine) vehicle on a road trip, it is normal to fully fill the tank. Why not fill the tank? It has little impact on the time taken, and it gives more range before the next refuel is needed. We don’t think much about how long it takes to fill the tank with fuel, because unless we drive a huge truck, time difference between fill and partial fill makes little difference. The visit requires turning off the highway, getting to the pump if there is a queue, and the paying can step can take as long or even longer than the filling time. The filling time is just part of the overall stop, and how long the filling takes is not normally that significant. takes to fill the tank.

When recharging an EV (electric vehicle) on a road trip, there are reasons why it is not always best to ‘fill the tank’:

  • For some EVs, charging that last few percent is slower, and not worth the extra wait, so it can be best and most time efficient to recharge only to 80 or 90%, depending on the vehicle.
  • Recharging can generate heat in the battery, and the longer the recharge, the more heat, so more frequent partial recharges can a avoid a car reducing recharging speed to avoid excess heat.
  • Available rechargers may be slow, making a ‘top up’ and then travelling to a faster charger the best solution.
EV charging station within outdoor parking area.

Paying for recharging differs from traditional payment for refuelling. Chargers are all pay at the pump and their is no associated cashier. While with traditional refuelling there is normally a staff member somewhere, most often there is no human involved at all with recharging. Modern chargers can communicate with the car, so connecting the charger connects communication with the charging network operator. If there is already an account with the correct options selected, the cost of charging cam be charged to the account of the car owner automatically. Otherwise, paying is often through an ‘app’ on a mobile phone, and there can be lower prices on charging networks if the car owner is a subscriber. It can make sense to become a subscriber for the duration of a road trip. Electricity from the charging network operator can be more expensive than directly from the electricity company as may be the case at home, although charging networks can offer special deals that become bundled with a car purchase.

With an EV, in 2021, a recharge stop should require no more than 20 minutes with newer vehicles, but could take 40 minutes with some models. How long should be allocated for a given recharge can also depend on what there is to do while recharging. Is it time for breakfast, lunch or diner? If you were going to be stopped anyway, even a slower recharger can be time efficient.

If a road trip stops will include trying to feel refreshed and perhaps involves a meal and bathroom stops, then there may be no time penalty as these things can happen during charging, unlike with an ICE refuelling. However, if in a hurry, todays EVs can extend how long your road trip stops can take.

The Achilles Heel: Road Trip Recharge Ratios.

The Missing EV spec: Driving Time/Recharge Time Ratio.

Both ICE vehicles and EVs get their energy from a chemical reaction.

  • With an ICE vehicles, chemicals from the reaction become waste, and it gets loaded up with new ingredients.
  • With an EV, chemicals from the reaction are saved, and with an external supply of energy, the reaction is reversed.

The by discarding the reaction output as waste, and just using more chemicals as new fuel, the ICE vehicle is ready quickly. The process of taking the ‘waste’ products, and converting back into fuel takes millions of years, but happens outside the car. The reverse process is ignored by the car.

As the EV uses no new fuel, it needs time and energy to restore the chemicals to their original state. The same reaction that is used to produce the energy for the car must be run in reverse to restore the ‘waste’ inside the battery, back the chemicals that represent the charged state. Since the reverse process is run inside the car, the car must wait while the reverse process is run. If both the forward and reverse reactions ran at the same speed, 1 hour of driving would then need 1 hour of recharging. Fortunately, a lot of science has been applied to enable running the reverse ‘recharge’ reaction much faster, but there are limits.

However, for EVs, there is a ratio. Driving at any constant speed requires a number of kilowatts every hour, and recharging can replace a number of kilowatts ever hour. If the rations between these number is 4, then four hours driving would require 1 hour of charging. Double the battery size will double both numbers, but would not change the ratio of driving time to charging time.

What will change the ratio, is speed. The faster you drive, the lower the ratio, so you will gain less time from driving faster in an EV. Just as engine power can be a curved graph, so would the Driving Time/Recharge Time ratio. However, if the national speed limit is 110 km/h (68.35 mph) as in Norway, then the ration at this speed would be most important to you. In France or Germany, the ratio at 130 km/h (80.8 mph) might be more important, and what is most important will change will local conditions.

Real World Driving Time/Recharge Time Ratios at 110 km/h: from Bjørn Nyland.

Bjørn Nyland 1,000 Challenge.

EV vlogger Bjørn Nyland tests car using his 1,000 challenge in Norway. His reference time for the challenge ‘using a fossil refence car‘ is 9 hours 25 minutes (9:25) at an average of 106.2 km/h. While in theory if remaining exactly at the speed limit and without stopping at all, the journey could have been 9 hours and just over 5 minutes, this is not the real world, and 20 minutes lost between one refuelling stops and traffic delay when driving 1,000 km is very efficient.

Comparing a selection of cars from Bjørn’s data using their excess time over the reference and being recharge time to calculate the ratio at 100 km/h reveals:

  • 18.8 – 2021 Telsla Model 3: 18.8
  • 16.1 – Hyundai Ioniq 5
  • 10.3 – Audi e-tron 55, Mercedes EQA, Tesla Model X
  • 9.4 – Ford Mustang Mach-E LR RWD
  • 8.7 – BMW iX3
  • 8.1 – VW ID4 82 kWh
  • 6.3 – Tesla Model S P85
  • 5.9 – Mercedes EQC 400
  • 4.5 – Ford Mustang Mach-E LR AWD
  • 3.8 – Audi e-tron 50

As you can see, older cars perform much worse, and newer cars such as the Lucid Air, or XPeng models using 480 kw charging, should perform even better than any on this list so far.

Data For Driving Time/Recharge Time Ratios at 90 km/h and 130 km/h: Battery Life.

The you tube channel ‘battery life’ does full range tests in Germany at both 90 km/h and 130 km/h. These videos are interesting and and give insights into other factors affecting range, however tests focus on driving cars from full charge until range is fully used and then charging until the battery is completely charged. This is useful data, but differ from what you would get in the real world, when charging when convenient and you want to stop, and not necessarily waiting for an absolutely full charge.

Human Recharge Ratios.

When on a road trip, it is recommended, that the driver rests every 2 hours for around 15 minutes. Some people ignore these recommendations, and other instead use multiple drivers, but until there is genuine level 4 or level 5 self driving cars, it is recommended to take the breaks even if swapping drivers.

Fifteen minutes every hour would be a ration of 4 to 1, fifteen minutes every 2 hours is a ratio of 8 to 1. This means for any vehicle with a recharge ratio above 8 to 1, the car in theory requires less recharge time than the driver.

In practice, not every ideal stop for humans would have the ideal car charging equipment. There are road trips where the it is the journey and not the destination, and these trips normally have more generous windows for charging, but when it is all about the destination, the ideal EV would have a ratio of 16 or better, and currently there are only two entries on the list that comply. Fortunately, at least half of the mainstream EVs being released in the next year would be capable of 16, and things will only get better after that.

Meantime, look carefully at the recharge ratio when considering an EV that will do lots of road trips.

The Fine Print: Factors Affecting Real World Recharge Ratios.

Its Cruising Speed, Not Average Speed, That Is Important For Efficiency.

I have seen calculations where people make comments such as:

  • ‘The average speed was only 90 km/h, not 110 km/h, so the real consumption would be higher’.
  • or ‘we were delayed by road works, so it was necessary to drive faster to make up time’.

The logic here is a trap. Consider three trips:

  1. A person drives for 1 hour at 110 km/h.
    • Average speed 110 km/h.
  2. A person drives for 30 minutes at 110 km/h, waits 15 minutes for roadworks, then resumes 110 km/h for 30 mins.
    • Average speed 88 km/h.
  3. A person drives for 45 minutes at 130 km/h, then 15 minutes at 50 km/h.
    • Average speed 110 km/h

Number 1 is obviously all travelling at 110 km/h. But number 2 is also all travelling at 110 km/h. The 15 minutes stopped lowered the average speed for the day, but had no impact more impact on the average speed the car travelled at when it was being driven, then if the person in number 1 was asked to wait at the finish for 15 minutes before calculating the average. For number 3, the car travelled 97.5 kilometres at 130 km/h, which is 90% of the distance. The 15 minutes of driving slower will not suddenly recover fuel used when driving faster.

Many Other Factors Effect Efficiency.

Internal combustion engines are less efficient at best, and are rarely at best, which results them being around 5x less energy efficient than electric vehicles in typical driving. This means everything else that effects efficiency becomes more noticeable in an EV. For this reason electric vehicles use the more efficient heat pumps in place of traditional air conditioners, as every thing that uses energy matters more.

The result is all of the following factors impact efficiency, and thus recharge ratio:

  • Availability of Optimum Charging.
    • Vehicles such as the Ioniq 5 could perform better in Bjørn’s test once faster chargers are available.
  • Wheel size, with smaller wheels and taller tyres usually more efficient.
    • 19″ wheels usually give longer range than 20″ or 21″
  • Road conditions such are rain or snow.
    • In heavy rain, consumption will increase.
  • Temperature Extremes.
    • Batteries operate best within a temperature range, and it can take energy to keep them within this range.

Wireless Charging: The Next Step?

Wireless Charging At Home: Still rare, but becoming available now.

Having to plug in each night when you park may not take long, and if we can remember to charge our phones, it may not seem to much of a burden, but just imagine if as you a pulling up, the car automatically guides itself to the right position to recharge. This is new, but the it is already down as an option with Hyundai Genesis EV60 and the BMW530e. As the WiTricity wireless charging follows an open standard, and is said to be as efficient as a cable, wireless charging could take over. VW aims to wirelessly charge a Porsche Taycan to 80% in 10 minutes.

Wireless Charging On The Move: In Early Trials.

Like the technology used by our smart devices, the system needs vehicle-mounted receivers to work. According to the company, this is something that has not been implemented yet as a factory feature by any renowned carmaker but can be easy and cost-effective to add on existing and future EV models.

In terms of logistics, the only inconvenience is that a portion of the asphalt needs to be removed and replaced. Other than that, the system can connect to existing power grids without the need for additional infrastructure or transformation stations. It uses management units placed on the sides of the road to communicate with the receivers on the vehicles and transfer energy.

ElectReon is involved in multiple pilot programs to test the feasibility of this technology. Recently, the company has completed the deployment of its dynamic wireless charging system on a 1.65-km (1.02-mile) public road in Gotland, Sweden.

Sweden Successfully Tests Wireless Charging Road Set to Revolutionize Mobility

Just as wireless charging is becoming the normal with mobiles, we could move to a world where ‘stopping to refuel’ just doesn’t happen. We recharge for the lowest cost at home overnight, particularly if we have solar power, and on the move on the highway on a road trip, all for lower cost than refuelling an ICE vehicle.

Problem: No Home Charging? Upgrades, Street Chargers, Or Solar A Solution?

Many People Have No ‘Home’ Charging: Only On Street Parking, Or No Power Socket.

Statistics on what percentage of people have parking with access to a mains socket, will vary not just from country to country, from locality to locality, and even within a town or city, area within that town or city. I found specifications for the UK that state that 25% of all vehicles in Britain are parked on the street when at home. However, even some vehicles with off-street parking, do not have access to electricity in their allocated space. For example, for apartment complexes, providing mains electric car power in each allocated space or garage, would require the addiction of significant extra infrastructure to facilitate measuring the power usage at each allocated space, which is most often not currently in place.

Some homes have little or no off street spaces, and some families have more cars than spaces.

This division between those with access to a power socket for home charging, and those without, could be the great divide of the electric vehicle experience. This is not a question of access to rapid charging at home, as most people, particularly in built up areas, can achieve most of the charging they need from a regular mains socket. Even for those this is not a perfect solution, a combination of mains socket charging with occasional use of rapid charging is far far better than no home charging at all.

Right Now, Think Twice Before Buying If You Can’t Charge At Home.

There are so many great home charging options, and even standard wall socket will satisfy most needs, and matching that experience for the as many as around 50% of all people without access to a power point where parked when at home is a real challenge. Some will have suitable charging at work, but otherwise, at this time, for these people owning an EV is going to be far from the experience it should be. The best experience requires charging from home. Without charging at home:

  • Electricity costs more as recharging stations are resellers of electricity, increasing car running costs.
  • There is the added inconvenience of needing to find time to go to recharging stations.
  • Battery life with most batteries is reduced by rapid charges and the deeper cycles that go with rapid charging.

For a move to electric cars across society, this problem requires serious attention. Society has had 100 years to adopt and evolve around fossil fuel cars, some evolution is now required around electric vehicles. This is the key evolution required.

There are shopping centres with charging spaces for EVs, and some people can charge at their place of work, but these are not universal solutions, and while the lure of often free charging is a lure for customers right now, it is hard to see this as part of wide scale solution.

However, there are solutions coming. The two main reasons for not being able to charge at home are:

  1. Home parking is in an underground carpark, without available power for charging, as often is the case with apartments.
  2. On street parking is the only available parking at home.
The older solution.

Problem number 1 should be resolved as more people have the need and as upgrading underground parking is practical once enough people need it. The biggest problem here is that charging networks trying to offer

Charging Solutions For On Street Parking.

But for problem number 2, on street parking, solutions are more complex. There are many proposals, such as such as the one in the video to the right, with posts that can be housed at the street side, as well as other solutions that convert street lamps into charging posts.

And the new.

While there are proposals for on street parking with power, who funds such infrastructure is complex issue, and normally assumes those charging on street will be paying a premium for electricity compared to those charging at home in order to fund the scheme operator.

‘Electrifying’ the street can work in densely populated areas, particularly with wireless charging, but there is a risk that the electricity will come at a premium to help fund the infrastructure. Even when paying a premium for electricity, EVs are still less expensive to operate than ICE vehicles, but it would be better if everyone had price parity. Society regards electricity to the home as an essential service, and with EVs, electricity to the car parking location may need similar consideration.

There is a social question to be answered.

There is another solution: Solar EVs.

Unlike the solar challenge races, a regular car cannot travel 1,000km (600 miles) on solar energy per day, but up to 60km of charge per day is possible, and given the average distance driven per by vehicles, then that may just be enough to keep the battery sufficiently charged most of the time for most people.

There are soon to be released cars:

Tesla even has solar charging plans for their Cybertruck. It is all very promising, and all are taking orders, but Tesla has nothing is in mass productions at time of writing.

More articles on solar vehicles:

Off Grid Solar Vehicles.

Another type of charging is charging when parked at a remote location. This is most relevant for vehicles that may spend long period of time at a remote location such as campers.

A proof of concept vehicle has already been able to gain 130km (80 miles) of range per day. All of this additional range is completely without cost of carbon footprint.

There are also a umber of camping conversions and camping trailers that propose using solar power for not just camping, but also to charge the vehicle.

Many systems are proposed to facilitated solar charging the Tesla Cybertruck, but like the truck, these are still proposals.t

Safety: Recharging Vs Refuelling.

Refuelling: EVs Vs Combustion, A Surprisingly Change.

Before even discussing range anxiety with EVs, it is worth considering the role refuelling plays the range we need.

Part of the reason our current vehicles need the range we are now expect, is that refuelling with gasoline or diesel, is not something we want to do every day. Most of us do not refuel until less the tank is less than half full.

In normal day to day living, the range of our vehicle determines how often we have to refuel. Refuelling takes time out of our day. There can be queues and we can do nothing else while we refuel. Fuel is also dangerous, and has fumes that are also dangerous, and this determines the character of the refuelling point, and why we are required to pay attention to what we are doing.

The National Fire Protection Association requires that they’re put up as a precaution. Phones do cause static electricity and just because it hasn’t happened yet, that doesn’t mean it never could. Their rules also state that you’re not allowed to use electronic materials at gas pumps, and cell phones fall into that category. The NFPA advises that you always follow all rules posted at gas stations and consult your phone’s owner manual for information on proper use.
The primary reason you shouldn’t use your phone at the pump (besides the fact that there are signs telling you not to) is that it’s a major distraction.

Why You Need to Stop Using Your Phone When Pumping Gas

Now consider electric refuelling. All that is required is a power point. Refuelling can be at the office, at home, or even at the supermarket. You don’t need to pay attention, and you won’t toxic chemicals on your hands or clothes. The worst way to refuel an electric vehicle, is to follow the old behaviour, and go to a location specifically to refuel and have nothing else to do while refuelling. Refuelling EVs can be no more inconvenient then using the right parking space, and is definitely best not done in the old way, as a special place just for refuelling.

This really impacts needed for those who can charge at home or the office. A change in thinking from “I refuel when the time comes” to “whenever I park here I ‘connect’ the car”. Then, every day their vehicle has the full range, in place of a potentially half empty tank, where the half already consumed has saved the driver the need to refuel during the past few days.

In normal use, a major role of the ‘range’ of a gasoline/petrol or diesel vehicle, is saving you from having to refuel everyday. That aspect of ‘range’ no longer applies to anyone with some form of permanent, or electrified parking space.

The Charging Off Grid Problem.

This section to be added.

Portable or home wind charging is also possible.

Recharging Summary and Conclusion.

There are a few key takeaways on the situation right now, in late 2021:

  • Recharging on road trips is a step backwards from with ICE Vehicles, although in most cases in practice, only small step back.
  • Periodic recharging for when not on a road trip, for those with access to home charging is a significant step forward from the experience with ICE vehicles.
  • Without home recharging, periodic recharging (when not on a road trip), is significant step backward from the experience with ICE vehicles.

The biggest problem is that of finding solutions for those who cannot charge at home. The problem is that to create a level playing field with those who can charge at home, equitable solutions require access to electricity at home rates. Most of the focus is on solutions provided by companies who plan to earn a windfall on the margin the add to the price of electricity.

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