Malaysia must have come a long way since the ABB 50 kW DC charger was the only one around in Sunway. We now have a growing list of DC chargers, although some may argue that the government’s EV tax incentives are almost not enough to support the growing amount of EVs on the streets.
DC chargers are expensive equipment, so it is understandable that some operators have started charging for their services. After all, someone has to pay for equipment and electricity to fund further expansion. Even Tesla, famous for its initially superchargers for free use, has started charging for it.
Since charging is something new to everyone, there are some misconceptions or possibly sticker shocks when trying to figure out how much it costs to use a paid DC charger. This is expected because people are accustomed to paying a fixed price per liter of fuel for their car wherever they are in Malaysia, and there are many variables to consider with sudden charging.
So we decided to write a story to clarify some issues and provide some tips so that you can get the most out of your given DC charging session.
The number one tip on how to save money while using a DC charger is not to use a DC charger in the first place. No, we don’t want to sound like a boomer these days about how kids spend all their money on iced coffee. The way we fuel our ICE cars with gasoline, when someone unfamiliar with the EV hears how much it costs to fuel an EV with electrons, they automatically assume how much it costs to drive a car every day.
Generally, EV owners will charge the house with AC charger while sleeping at night. It can take hours to recharge a car with slow and low battery percentage from AC charging DC, but time is not really that important overnight because you are not using the car while you sleep and most of the time you just top up your charge instead of recharging from zero Please.
Based on the rate of residential electricity at the highest level, you will pay RM0.571 per kWh. This means that a BMW iX with 76.6 kWh battery will cost only RM43.74 to recharge from zero, and it will give you a WLTP range of 425 km (probably 350-400km in real life use). So running your EV is not as expensive as you think it is based on the price of the published DC charger.
So when do you need to use a paid DC charger? There really is a combination of two situations – when you want to save time, and when you have virtually no way to get back to your home charger.
A DC charger will be able to pump electrons into your car faster than an AC charger in your home. The BMW iX can take DC charging at a maximum rate of 150 kW, which is significantly faster than just 11 kW AC charging capacity.
Now here it becomes complicated and the charging curve comes to the title of this story. A charger may be able to supply 150 kW. And your car may be able to get 150 kilowatts. But this transaction of electrons will not always happen at 150 kW.
The first thing you need to do is find the charging curve of your car You can google it. Remember to look for the specific battery in your EV because different batteries have different curve sizes.
BMW iX 76.6 kWh battery charging curve
BMW iX 111.5 kWh battery charging curve
So here I have embedded the charging curve of two different BMW iX. The xDrive40, which comes with a 76.6 kWh battery, is now on sale in Malaysia. You can see that the maximum 150 kW charging rate can only be maintained from 0% to about 20%, after which the charging power continues to decrease. The charging curve provided by BMW goes up to only 80% after which the charging power drops significantly below 50 kW.
Since most DC charging in Malaysia is charged on a time basis, it is understandable to use the charger only for the period where your battery can be charged at a high rate. If you are connected to a charger when the rate is low, you are actually getting less kilowatts per minute, thus paying a higher price for electricity. Based on your charging curve, you can decide at any time you feel comfortable paying for your electrons per kWh. If you do not need additional charges, we recommend disconnecting about 80% or earlier.
You can see that iX with large battery can be charged at high rate and can maintain this rate for a very long time. This is why you need to find a specific charging curve for your battery as it is definitely different for each battery pack. So in this case, the owner of iX with big battery can pay more for his EV, but he gets more money while charging chargers with time based billing.
Why would this happen? This is how battery science works. Even your iPhone can maintain a fast charging from only a low battery percentage, and it slows down as soon as the battery is full. Some people explain this by using the metaphor of filling the hall seats. When the hall is empty, there are lots of empty seats, so it’s easy to get inside quickly and grab a seat. But as soon as the hall is filled, it becomes difficult to find an empty seat, so the rate at which the hall fills up becomes slower.
Of course, there’s one more reason you might want to use a DC charger – if you don’t have an AC charger at home. This may apply to many people because they live in a high-rise property with a JMB that does not take into account the idea of installing a charger in the parking area.
But it is a complex problem to solve and in that situation drivers may want to stop buying an EV for now for which there is no solution.
We hope this clarifies some questions about how much it costs to charge an EV in Malaysia If you have any additional questions please leave a comment and we will try to answer.