Charging stations with 350 kW are very expensive, but their proponents believe that "more is better" and refer to charging electric vehicles like gasoline stations.
Carmakers compete with their high-speed DC charging stations in the “who has more” competition. Tesla pioneered the deployment of a 120kW charger network, which was later upgraded to 150kW. Porsche showcased a 350 kW charger for its Taycan. Tesla has upgraded its newest stations to 250 kW. Other manufacturers' networks started with 50 kW, but as the CCS charging system improved, new installations (in particular on the Electrify America network) were brought up to 150 kW (some of them even more powerful).
The installation of second-tier chargers (with a capacity of 3 to 8 kW) turned out to be a mistake - the country was flooded with expensive charging stations, which the drivers of modern long-range electric vehicles practically do not use. These chargers are slow and either free or overpriced. Their installation makes sense only in residential areas, or near parking lots and at hotels - in places where people usually spend 4 hours or more. Nevertheless, many of these chargers are installed in places where people spend from 30 minutes to 2 hours (for example, in store parking lots).
Each kilowatt of power adds about 4 miles of range per hour of charging, so a 150 kW station running at full capacity could theoretically add up to 600 miles of range per hour for a car like the Tesla Model 3.
The problem is, it really can't. This is instantaneous speed, and the station only gives it out at the beginning of a charging session - as soon as the battery is half charged (or even earlier), the charging speed drops. It may be more accurate to say that a 150 kW station adds 100 miles in 10 minutes, but this is only true for a heavily discharged car. The charging station cannot add 200 miles in 20 minutes. Most cars run only 200-300 miles on a single charge anyway.
Are we wrong again?
Could such problems arise when deploying fast charges? I call the “who has more” peak power race discussed above the “petrol approach”. This approach arises when someone compares charging for electric vehicles with gasoline filling stations. The petrol approach implies the following situation: you are driving, notice that there is little fuel left, look for the nearest gas station and fill it with a full tank. As fast as you can.
Electrical thinking works differently. This approach implies the desire to charge the car while it is parked, not because it has a low battery, but, for example, when you are sleeping at home or in a hotel. In this approach, the charging speed does not matter, the main thing is that your car is fully charged while it is parked. When you go to a gas station, your main task is to refuel. Charging your electric vehicle should ideally be your secondary concern.
This does not mean that the need for super-fast charging does not arise. There are times when you don't have a top priority. When the importance of all tasks is about the same (although this does not happen), of course, you want to speed up things like charging the car. If the car can be recharged in less than 5 minutes, then charging can be compared to a regular refueling. Whether you're in a lonely interstate truck stop or in a suburban warehouse, you'll need this charger.
However, there is no complete balance. Very high charging power costs money. Charging stations are expensive, starting megawatts of electricity is also not cheap (not as expensive as building a gas station, but still tangible) This cost must be paid, and usually the price of electricity at such charging stations can be 2 to 5 times more than when charging from your station at home. Imagine this situation: You can refuel at home for $ 2.5 per gallon, and on the highway for $ 8 per gallon. What kind of gas station will you avoid unless absolutely necessary?
Another problem is that very fast charging will shorten battery life. This figure is difficult to convert to dollars, but it is really important. Many companies are working on chargers and batteries that will not suffer from this ailment, but for now, it is worth resorting to fast charging only when necessary.
People who can charge their car at home or in the office should take this opportunity as their primary option - with slow equipment and low charging costs. In fact, level 1 charging can often be the right choice, adding only 5-7 miles per hour. If the office can supply 5 low-power chargers for the price of one Level 2 charger, then that would be the best solution - most cars can only travel 40 miles a day. Several tier 2 charging stations can serve people who need a little more right now. (It should be noted that the slower charging of the first level of 2 kW is somewhat less efficient than the charging of the second level of 7 kW).
People who do not have exercises near their home or work, as well as car travelers, need a different solution. In situations like this, supercharging is the main solution (at least for Tesla).
"Medium-fast" charging
These 50kW charging stations are quite fast, but still expensive. It shouldn't be that way though.
The solution could be a wider deployment of "medium-fast" chargers operating in the 40-50 kW range. These charging stations are also not cheap, but they cost less than charging 150 kW or more. However, the market is trying to reduce their cost. I recently spoke with Wallbox, a European charging station supplier, and while pricing is out of the question, they are planning to produce significantly cheaper 50kW chargers.
The cost of a charger is only half the battle; the cost of high-power electrical infrastructure is also high. Even for an existing commercial building, adding hundreds of kilowatts of power may require renewed power supplies and costly wiring. 150 kW is serious, there can be big safety risks, and this increases the cost.
A quick charge is convenient to have in places where you can stop for a period of 20 minutes to an hour - in places like restaurants, grocery stores (and other large retail), bars and other meeting places. If the price of such chargers decreases so that they are everywhere, then they will be very convenient when traveling for shopping. The usage scenario will be very simple - put the car on charge and go about business, the charging payment will be calculated by a special protocol right through the cable. If the store wants to make a discount for charging, this can be done simply by touching the phone to a special sensor in the store (or, even better, automatically, after making a cashless payment for purchases).
Medium-fast charges are also good when traveling to restaurants. Even if you come to a fast food company and sit down to have a snack - it will take you about 35 minutes. The problem with restaurants is that their main job is for business lunches and dinners, so a trip to the restaurant and fast charging makes sense. Since you will need to park at the charging station, it is better to put several charges near the restaurant, and not one powerful one within 5-10 minutes walk from it (unless you can take take-out food next to the powerful charging station).
Available chargers and van parking
As noted, the cost of new electrical infrastructure can be a problem, especially when it comes to a small institution that just wants to install 2-3 charges. If you are building a large charging station, you will almost always have to make a new electrical system for it.
We need moderate charging capacities that can detect the current entering the building and do not deliver more power than the existing infrastructure can handle. Many buildings are very well supplied with electricity and use only a small portion of it most of the time, increasing appetites in situations where there is a lot of AC demand. The rest of the time they have idle resources.
Current electrical codes force electricians to sum up the loads in a building and apply a formula to them to estimate the capacity of the infrastructure needed. This formula helps to avoid overloading, and although it is not just the sum of all loads, the formula takes into account that most loads can occur in full at the same time. All of this concerns ordinary consumption, but it's easy to make a car charger that responds to changes in network congestion. Such a station can see that another device (for example, an air conditioner) is consuming a lot of energy, and reduce its power so that the total load remains at safe values. Now our electrical standards are only adapting to the emergence of such smart devices, but in the end, all these approaches will be consistent with each other.
In fact, a typical commercial building (like a shop) will almost always have enough energy to install a 50 kW charging station. However, this is not always true. Lack of power will simply slow down charging, and if this problem is not common, then you can put up with it - it is still cheaper than updating the electrical infrastructure everywhere. Such cases can also be determined in advance, since even from the temperature readings, it can be determined that the charging speed will be reduced. Drivers who use the app to locate a charging station will be told that the charger is operating at reduced power long before they reach that station.
An inexpensive, mild-fast charging station that does not require electrical upgrades (even if you supply multiple charges) may be the best option for retail stores. This kind of infrastructure might make sense in offices as well, although employees will have to go out and rearrange their cars so their colleagues can recharge too. An average employee will need about 10-15 kWh per day. You can also install one super-powerful charger, which 20 employees will have time to use (if they constantly run and change), but it is much easier and cheaper to simply install 20 first-level chargers that will work all day long. You can also install devices of the "one and a half" level - at 208 or 240 volts and 15 amperes.Such a charging station (close to the lower limits of the second level in terms of technical characteristics) is easy to make, and it can even be connected to the existing mains - thus its installation will be inexpensive, and the charging speed will be twice as high as that of the first level.
Van parks
RV parks have large supplies of electricity on days when they are not packed to capacity.
Van fleets are another interesting option for installing cheap chargers. Van parking areas tend to have a very powerful electrical infrastructure as they have to cope with a large number of vans, each with air conditioning. On more free days, these capacities are idle and park owners could install dynamic chargers with low charging costs. Today, fast charging stations are located mainly on the main highways; there are almost no charges in rural and suburban areas. Van parks, in turn, are almost everywhere. Many people prefer to travel on country roads.
EV drivers would love being able to use absolutely all roads, and would be using charging in van fleets (even if these are very slow Tier 2 stations) today. A 30-minute stop in a regular van parking lot doesn't make much sense, although there are always picnic tables to grab a bite to eat. Yes, in such a situation people will want to connect their car to a 150 kW station and charge at the same rate as ordinary cars fill a full tank at a gas station, but for van fleets it is still too expensive. People will tolerate one or two half-hour stops once a day if this gives them the opportunity to drive on country roads that were previously inaccessible to them.
An important message - do not treat electric vehicle charging stations as gas stations. It is necessary to understand - where people will actually need energy, and where they will stay long enough to receive it using chargers of different capacities. If you pay attention to the cost of chargers, you may find that slow chargers are better in some places and medium and ultra-fast chargers in others. And in many cases, the decision can be mixed.
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